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Dong K, Zhou Y, Guo J, Jiang Y, Zhang B, Wang Y, Chen Y. Cyclic methylsiloxanes in wastewater treatment plants: Occurrence, emissions, environmental distributions, and occupational exposure. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 951:175524. [PMID: 39155007 DOI: 10.1016/j.scitotenv.2024.175524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2024] [Revised: 08/12/2024] [Accepted: 08/12/2024] [Indexed: 08/20/2024]
Abstract
Cyclic methylsiloxanes (CMSs), widely found in wastewater treatment plants (WWTPs), are potentially hazardous to the environment and human health. In this study, the environmental behavior and human exposure risks of three CMSs (D4-D6) were evaluated in WWTPs located in Beijing and Kunming, Yunnan province. D5 had the highest concentrations in air, water, and sludge, with seasonal variation that consisted of a high concentration in summer and low concentration in winter. The CMS concentrations in air were 3-4-fold higher in the A2/O (Anaerobic-Anoxic-Oxic) treatment units than in the other units. CMS emissions to air, soil, and water from the Beijing WWTP were in the ranges of 3.4 × 104-5.0 × 104 kg·a-1, 4.5 × 102-7.5 × 102 kg·a-1, and 2.5 × 102-2.9 × 102 kg·a-1, constituting 98 %, 1.3 %, and 0.7 % of the total emissions, respectively. Total daily inhalation exposure doses of CMSs (ADDinh,CMSs) associated with four different jobs in WWTPs showed that wastewater treatment technicians had the highest ADDinh,CMSs (51 μg/kg/day), indicating that these people had the highest occupational exposure risk in WWTPs. Therefore, this study identified that atmospheric emission was the main environmental fate of CMSs in WWTPs, and provide a basis for the improvement of WWTP process and risk management decisions. ENVIRONMENTAL IMPLICATION: Assessing the environmental fate and occupational exposure risk of cyclic methylsiloxanes (CMSs) found in wastewater treatment plants (WWTPs) is crucial. This is the first study to identify that atmospheric emission was the main environmental fate of CMSs in WWTPs, especially D5; the inhalation exposure doses of CMSs were all significantly higher in the occupational population working in WWTPs. The results described in our study will help enhance the understanding of current knowledge base of environmental fate and exposure risk of CMSs in WWTPs, and provide a basis for the improvement of WWTP process and risk management decisions.
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Affiliation(s)
- Kaixin Dong
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Ying Zhou
- West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Junyu Guo
- West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu, Sichuan 610041, China.
| | - Yao Jiang
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Boya Zhang
- Department of Epidemiology, University of Michigan, Ann Arbor, MI, USA
| | - Yifei Wang
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Yuan Chen
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
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2
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Kumari K, Singh A, Marathe D. Cyclic volatile methyl siloxanes (D4, D5, and D6) as the emerging pollutants in environment: environmental distribution, fate, and toxicological assessments. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:38681-38709. [PMID: 36809612 DOI: 10.1007/s11356-023-25568-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 01/18/2023] [Indexed: 06/18/2023]
Abstract
Cyclic volatile methyl siloxanes (cVMS) have now become a subject of environmental contamination and risk assessment due to their widespread use and occurrence in different environmental matrices. Due to their exceptional physio-chemical properties, these compounds are diversely used for formulations of consumer products and others implying their continuous and significant release to environmental compartments. This has captured the major attention of the concerned communities on the grounds of potential health hazards to human and biota. The present study aims at comprehensively reviewing its occurrence in air, water, soil, sediments, sludge, dusts, biogas, biosolids, and biota and their environmental behavior as well. Concentrations of cVMS in indoor air and biosolids were higher; however, no significant concentrations were observed in water, soil, and sediments except for wastewaters. No threat to the aquatic organisms has been identified as their concentrations do not exceed the NOEC (maximum no observed effect concentration) thresholds. Mammalian (rodents) toxicity hazards were not very evident except for the occurrence of uterine tumors in very rare cases under long-term chronic and repeated dose exposures in laboratory conditions. Human relevancy to rodents were also not strongly enough established. Therefore, more careful examinations are required to develop stringent weight of evidences in scientific domain and ease the policy making with respect to their production and use so as to combat any environmental consequences.
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Affiliation(s)
- Kanchan Kumari
- CSIR-National Environmental Engineering Research Institute (NEERI), Kolkata Zonal Centre, 700 107, Kolkata, West Bengal, India.
- Academy of Scientific and Innovative Research (AcSIR), Uttar Pradesh, Ghaziabad, 201 002, India.
| | - Anshika Singh
- Academy of Scientific and Innovative Research (AcSIR), Uttar Pradesh, Ghaziabad, 201 002, India
- CSIR-National Environmental Engineering Research Institute (NEERI), Nagpur, 440020, Maharashtra, India
| | - Deepak Marathe
- Academy of Scientific and Innovative Research (AcSIR), Uttar Pradesh, Ghaziabad, 201 002, India
- CSIR-National Environmental Engineering Research Institute (NEERI), Nagpur, 440020, Maharashtra, India
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3
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Brunet C, Marek RF, Stanier CO, Hornbuckle KC. Concentrations of Volatile Methyl Siloxanes in New York City Reflect Emissions from Personal Care and Industrial Use. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:8835-8845. [PMID: 38722766 PMCID: PMC11112754 DOI: 10.1021/acs.est.3c10752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 04/25/2024] [Accepted: 04/26/2024] [Indexed: 05/22/2024]
Abstract
Volatile methyl siloxanes (VMS) are a group of organosilicon compounds of interest because of their potential health effects, their ability to form secondary organic aerosols, and their use as tracer compounds. VMS are emitted in the gas-phase from using consumer and personal care products, including deodorants, lotions, and hair conditioners. Because of this emission route, airborne concentrations are expected to increase with population density, although there are few studies in large urban centers. Here, we report summertime concentrations and daily variations of VMS congeners measured in New York City. Median concentrations of the 6 studied congeners, D3 (20 ng m-3), D4 (57 ng m-3), D5 (230 ng m-3), D6 (11 ng m-3), L5 (2.5 ng m-3), and L7 (1.3 ng m-3) are among the highest reported outdoor concentrations in the literature to date. Average congener ratios of D5:D4 and D5:D6 were consistent with previously reported emissions ratios, suggesting that concentrations were dominated by local emissions. Measured concentrations agree with previously published results from a Community Multiscale Air Quality model and support commonly accepted emissions rates for D4, D5, and D6 of 32.8, 135, and 6.1 mg per capita per day. Concentrations of D4, D5, D6, L5, and L7 and total VMS were significantly lower during the day than during the night, consistent with daytime oxidation reactivity. Concentrations of D3 did not show the same diurnal trend but exhibited a strong directional dependence, suggesting that it may be emitted by industrial point sources in the area rather than personal care product use. Concentrations of all congeners had large temporal variations but showed relatively weak relationships with wind speed, temperature, and mixing height.
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Affiliation(s)
- Christopher
E. Brunet
- Department
of Civil and Environmental Engineering, IIHR-Hydroscience & Engineering, University of Iowa, Iowa City Iowa 52242, United States
| | - Rachel F. Marek
- Department
of Civil and Environmental Engineering, IIHR-Hydroscience & Engineering, University of Iowa, Iowa City Iowa 52242, United States
| | - Charles O. Stanier
- Department
of Chemical and Biochemical Engineering, IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City Iowa 52242, United States
| | - Keri C. Hornbuckle
- Department
of Civil and Environmental Engineering, IIHR-Hydroscience & Engineering, University of Iowa, Iowa City Iowa 52242, United States
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4
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Zhang L, Chen X, Luo G, Liu S, Guo P, Ye Y, Jiang R. Unraveling the distribution characteristic of cyclic volatile methylsiloxanes in various environmental media of a wastewater treatment plant. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:169106. [PMID: 38065489 DOI: 10.1016/j.scitotenv.2023.169106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 11/27/2023] [Accepted: 12/02/2023] [Indexed: 12/17/2023]
Abstract
Cyclic volatile methylsiloxane (cVMS) is extensively used in consumer products and frequently detected in various environmental media, including water and air. In this study, we developed reliable and convenient methods to sample three cVMS compounds: octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) in water and air samples collected from different tanks within a wastewater treatment plant (WWTP). The concentrations of D4, D5, and D6 in the water samples ranged from 0.40 to 8.0 μg L-1, 0.35 to 91 μg L-1, and 0.54 to 17 μg L-1, respectively. In the air samples, these concentrations varied from 0.34 to 20 μg m-3, 0.34 to 128 μg m-3, and 0.08 to 12 μg m-3, respectively. It is worth noting that the air-water distribution coefficient (Kaw) for these three cVMS exhibited a strong correlation with their water solubility. Moreover, fugacity fractions indicated a net evaporation process from water to the atmosphere. Furthermore, we investigated the distribution of cVMS between the gaseous and particulate phases. The results revealed a significant fraction, exceeding 72 %, of cVMS resided in the gas phase. D4 and D5 predominate in the gaseous phase, while D5 and D6 are the principal constituents within the particulate phase. The distribution coefficient characterizing the partitioning of cVMS compounds between the gaseous and particulate (Kp) exhibited a strong correlation with their corresponding octanol-air partitioning coefficients (Koa). These findings contribute to a better understanding of the distribution of cVMS in diverse environmental media and the underlying mechanism governing their dispersion.
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Affiliation(s)
- Lifang Zhang
- Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology, Guangdong Provincial Engineering Research Center for Ambient Mass Spectrometry, Institute of Analysis, Guangdong Academy of Sciences (China National Analytical Center, Guangzhou), Guangzhou 510070, China
| | - Xinlv Chen
- Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology, Guangdong Provincial Engineering Research Center for Ambient Mass Spectrometry, Institute of Analysis, Guangdong Academy of Sciences (China National Analytical Center, Guangzhou), Guangzhou 510070, China
| | - Gan Luo
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 511443, China
| | - Shuqin Liu
- Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology, Guangdong Provincial Engineering Research Center for Ambient Mass Spectrometry, Institute of Analysis, Guangdong Academy of Sciences (China National Analytical Center, Guangzhou), Guangzhou 510070, China
| | - Pengran Guo
- Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology, Guangdong Provincial Engineering Research Center for Ambient Mass Spectrometry, Institute of Analysis, Guangdong Academy of Sciences (China National Analytical Center, Guangzhou), Guangzhou 510070, China
| | - Yuanjian Ye
- Guangzhou Quality Supervision and Testing Institute, Guangzhou 511400, China
| | - Ruifen Jiang
- Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology, Guangdong Provincial Engineering Research Center for Ambient Mass Spectrometry, Institute of Analysis, Guangdong Academy of Sciences (China National Analytical Center, Guangzhou), Guangzhou 510070, China; Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 511443, China.
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5
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Jiang J, Ding X, Patra SS, Cross JN, Huang C, Kumar V, Price P, Reidy EK, Tasoglou A, Huber H, Stevens PS, Boor BE, Jung N. Siloxane Emissions and Exposures during the Use of Hair Care Products in Buildings. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:19999-20009. [PMID: 37971371 DOI: 10.1021/acs.est.3c05156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2023]
Abstract
Cyclic volatile methyl siloxanes (cVMS) are ubiquitous in hair care products (HCPs). cVMS emissions from HCPs are of concern, given the potential adverse impact of siloxanes on the environment and human health. To characterize cVMS emissions and exposures during the use of HCPs, realistic hair care experiments were conducted in a residential building. Siloxane-based HCPs were tested using common hair styling techniques, including straightening, curling, waving, and oiling. VOC concentrations were measured via proton-transfer-reaction time-of-flight mass spectrometry. HCP use drove rapid changes in the chemical composition of the indoor atmosphere. cVMS dominated VOC emissions from HCP use, and decamethylcyclopentasiloxane (D5) contributed the most to cVMS emissions. cVMS emission factors (EFs) during hair care routines ranged from 110-1500 mg/person and were influenced by HCP type, styling tools, operation temperatures, and hair length. The high temperature of styling tools and the high surface area of hair enhanced VOC emissions. Increasing the hair straightener temperature from room temperature to 210 °C increased cVMS EFs by 50-310%. Elevated indoor cVMS concentrations can result in substantial indoor-to-outdoor transport of cVMS via ventilation (0.4-6 tons D5/year in the U.S.); thus, hair care routines may augment the abundance of cVMS in the outdoor atmosphere.
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Affiliation(s)
- Jinglin Jiang
- Lyles School of Civil Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Xiaosu Ding
- Lyles School of Civil Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Satya S Patra
- Lyles School of Civil Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Jordan N Cross
- Lyles School of Civil Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Chunxu Huang
- Lyles School of Civil Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Vinay Kumar
- O'Neill School of Public and Environmental Affairs, Indiana University, Bloomington, Indiana 47405, United States
| | - Paige Price
- O'Neill School of Public and Environmental Affairs, Indiana University, Bloomington, Indiana 47405, United States
| | - Emily K Reidy
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | | | - Heinz Huber
- Edelweiss Technology Solutions, LLC, Novelty, Ohio 44072, United States
| | - Philip S Stevens
- O'Neill School of Public and Environmental Affairs, Indiana University, Bloomington, Indiana 47405, United States
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Brandon E Boor
- Lyles School of Civil Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Nusrat Jung
- Lyles School of Civil Engineering, Purdue University, West Lafayette, Indiana 47907, United States
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6
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Le TM, Le Quang H, Tran AH, Quang MB, Vu ND, Thi HN, Khanh HV, Kannan K, Tran TM. Co-occurrence of phthalic acid esters (PAEs) and cyclic volatile methylsiloxanes (cVMSs) in fine particulate matter (PM 0.5 and PM 0.1) collected from an industrial area in Vietnam. ENVIRONMENTAL RESEARCH 2023; 237:117018. [PMID: 37657605 DOI: 10.1016/j.envres.2023.117018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 08/10/2023] [Accepted: 08/28/2023] [Indexed: 09/03/2023]
Abstract
Distribution patterns of 10 phthalic acid diesters (PAEs) and four cyclic volatile methylsiloxanes (cVMSs) were investigated in fine particulate matter (PM0.1 and PM0.5) collected from Bac Ninh, an industrial province in Vietnam during September-October in 2021. Total concentrations of PAEs found in PM0.1 and PM0.5 were in the ranges of 1.76-372 (median: 34.0 ng/m3) and 2.23-895 ng/m3 (median: 15.4 ng/m3), respectively. Among PAEs, di-n-butyl phthalate (DBP) was the most abundant compound found in PM0.1, whereas, di-2-(ethyl)hexyl phthalate (DEHP) was measured at the highest concentration in PM0.5. Total concentrations of cVMSs measured in PM0.1 and PM0.5 were in the ranges of method quantification limit (MQL)-203 (median: 2.10 ng/m3) and MQL-537 ng/m3 (median: 0.389 ng/m3), respectively. Among cVMSs, decamethylcyclopentasiloxane (D5) was found at the highest concentration in both PM0.1 and PM0.5 fractions of particulate matter. The concentration ratios between PAEs and cVMSs in PM0.1/PM0.5 were greater than 1 (except di-n-octyl phthalate: DnOP), suggesting that these chemicals tend to sorb to PM0.1 more preferentially than PM0.5. Among sampling locations, high concentrations of PAEs and cVMSs were found at traffic intersections (Que Vo district) and a craft village (Tu Son city). Relatively stronger correlations existed between cVMSs pairs in PM0.1 and PM0.5 (correlation coefficient: 0.73-1) than those of PAEs (-0.83-0.90). The human exposure doses to PAEs and cVMSs through inhalation of particulate matter were estimated based on the measured concentrations in PM0.1 and PM0.5 fractions. The estimated exposure doses of PAEs and cVMSs for infants (7.1 ng/kg-bw/d and 2.5 ng/kg-bw/d) were higher than those for adults (2.6 ng/kg-bw/d and 0.9 ng/kg-bw/d).
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Affiliation(s)
- Thuy Minh Le
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi, 10000, Viet Nam; Center for Research and Technology Transfer, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi, 10000, Viet Nam
| | - Huong Le Quang
- Center for Research and Technology Transfer, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi, 10000, Viet Nam
| | - Anh Hai Tran
- Center for Research and Technology Transfer, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi, 10000, Viet Nam
| | - Minh Bui Quang
- Center for Research and Technology Transfer, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi, 10000, Viet Nam
| | - Nam Duc Vu
- Center for Research and Technology Transfer, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi, 10000, Viet Nam
| | - Huong Nguyen Thi
- Center for Research and Technology Transfer, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi, 10000, Viet Nam
| | - Hoa Vu Khanh
- Center for Research and Technology Transfer, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi, 10000, Viet Nam
| | | | - Tri Manh Tran
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi, 10000, Viet Nam.
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7
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Yao P, Holzinger R, Materić D, Oyama BS, de Fátima Andrade M, Paul D, Ni H, Noto H, Huang RJ, Dusek U. Methylsiloxanes from Vehicle Emissions Detected in Aerosol Particles. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:14269-14279. [PMID: 37698874 PMCID: PMC10537456 DOI: 10.1021/acs.est.3c03797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/13/2023]
Abstract
Methylsiloxanes have gained growing attention as emerging pollutants due to their toxicity to organisms. As man-made chemicals with no natural source, most research to date has focused on volatile methylsiloxanes from personal care or household products and industrial processes. Here, we show that methylsiloxanes can be found in primary aerosol particles emitted by vehicles based on aerosol samples collected in two tunnels in São Paulo, Brazil. The aerosol samples were analyzed with thermal desorption-proton transfer reaction-mass spectrometry (TD-PTR-MS), and methylsiloxanes were identified and quantified in the mass spectra based on the natural abundance of silicon isotopes. Various methylsiloxanes and derivatives were found in aerosol particles from both tunnels. The concentrations of methylsiloxanes and derivatives ranged 37.7-377 ng m-3, and the relative fractions in organic aerosols were 0.78-1.9%. The concentrations of methylsiloxanes exhibited a significant correlation with both unburned lubricating oils and organic aerosol mass. The emission factors of methylsiloxanes averaged 1.16 ± 0.59 mg kg-1 of burned fuel for light-duty vehicles and 1.53 ± 0.37 mg kg-1 for heavy-duty vehicles. Global annual emissions of methylsiloxanes in vehicle-emitted aerosols were estimated to range from 0.0035 to 0.0060 Tg, underscoring the significant yet largely unknown potential for health and climate impacts.
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Affiliation(s)
- Peng Yao
- Centre for Isotope Research (CIO), Energy and Sustainability Research Institute Groningen (ESRIG), University of Groningen, Groningen 9747 AG, The Netherlands
| | - Rupert Holzinger
- Institute for Marine and Atmospheric Research, IMAU, Utrecht University, Princetonplein 5, Utrecht 3584 CC, The Netherlands
| | - Dušan Materić
- Institute for Marine and Atmospheric Research, IMAU, Utrecht University, Princetonplein 5, Utrecht 3584 CC, The Netherlands
- Department of Analytical Chemistry, Helmholtz Centre for Environmental Research─UFZ, Permoserstrasse 15, 04318 Leipzig, Germany
| | - Beatriz Sayuri Oyama
- Institute for Marine and Atmospheric Research, IMAU, Utrecht University, Princetonplein 5, Utrecht 3584 CC, The Netherlands
- Institute of Astronomy, Geophysics and Atmospheric Sciences, University of São Paulo, São Paulo 05508-090, Brazil
| | - Maria de Fátima Andrade
- Institute of Astronomy, Geophysics and Atmospheric Sciences, University of São Paulo, São Paulo 05508-090, Brazil
| | - Dipayan Paul
- Centre for Isotope Research (CIO), Energy and Sustainability Research Institute Groningen (ESRIG), University of Groningen, Groningen 9747 AG, The Netherlands
| | - Haiyan Ni
- Centre for Isotope Research (CIO), Energy and Sustainability Research Institute Groningen (ESRIG), University of Groningen, Groningen 9747 AG, The Netherlands
- State Key Laboratory of Loess and Quaternary Geology, Center for Excellence in Quaternary Science and Global Change, Key Laboratory of Aerosol Chemistry & Physics, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China
| | - Hanne Noto
- Institute for Marine and Atmospheric Research, IMAU, Utrecht University, Princetonplein 5, Utrecht 3584 CC, The Netherlands
| | - Ru-Jin Huang
- State Key Laboratory of Loess and Quaternary Geology, Center for Excellence in Quaternary Science and Global Change, Key Laboratory of Aerosol Chemistry & Physics, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China
| | - Ulrike Dusek
- Centre for Isotope Research (CIO), Energy and Sustainability Research Institute Groningen (ESRIG), University of Groningen, Groningen 9747 AG, The Netherlands
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Saini A, Chinnadurai S, Schuster JK, Eng A, Harner T. Per- and polyfluoroalkyl substances and volatile methyl siloxanes in global air: Spatial and temporal trends. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 323:121291. [PMID: 36796663 DOI: 10.1016/j.envpol.2023.121291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/20/2023] [Accepted: 02/12/2023] [Indexed: 06/18/2023]
Abstract
The study reports on the atmospheric concentrations of per- and polyfluoroalkyl substances (PFAS) and volatile methyl siloxanes (VMS) measured using sorbent-impregnated polyurethane foam disks (SIPs) passive air samplers. New results are reported for samples collected in 2017, which extends temporal trend information to the period 2009-2017, for 21 sites where SIPs have been deployed since 2009. Among neutral PFAS, fluorotelomer alcohols (FTOHs) had higher concentrations than perfluoroalkane sulfonamides (FOSAs) and perfluoroalkane sulfonamido ethanols (FOSEs) with levels of ND‒228, ND‒15.8, ND‒10.4 pg/m3, respectively. Among ionizable PFAS, the sum of perfluoroalkyl carboxylic acids (PFCAs) and perfluoroalkyl sulfonic acids (PFSAs) in air were 0.128-781 and 6.85-124 pg/m3, respectively. Longer-chain i.e. C9-C14 PFAS, which are relevant to the recent proposal by Canada for a listing of long-chain (C9-C21) PFCAs to the Stockholm Convention, were also detected in the environment at all site categories including Arctic sites. Cyclic and linear VMS ranged between 1.34‒452 and 0.01-12.1 ng/m3, respectively, showing dominance in urban areas. Despite the wide range of levels observed across different site categories, geometric means of the PFAS and VMS groups were fairly similar when grouped according to the five United Nations regions. Variable temporal trends in air (2009-2017) were observed for both PFAS and VMS. PFOS, which has been listed in the Stockholm Convention since 2009, is still showing increasing tendencies at several sites, indicating constant input from direct and/or indirect sources. These new data inform international chemicals management for PFAS and VMS.
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Affiliation(s)
- Amandeep Saini
- Air Quality Processes Research Section, Environment and Climate Change Canada, Toronto, Ontario, M3H 5T4, Canada.
| | - Sita Chinnadurai
- Air Quality Processes Research Section, Environment and Climate Change Canada, Toronto, Ontario, M3H 5T4, Canada
| | - Jasmin K Schuster
- Air Quality Processes Research Section, Environment and Climate Change Canada, Toronto, Ontario, M3H 5T4, Canada
| | - Anita Eng
- Air Quality Processes Research Section, Environment and Climate Change Canada, Toronto, Ontario, M3H 5T4, Canada
| | - Tom Harner
- Air Quality Processes Research Section, Environment and Climate Change Canada, Toronto, Ontario, M3H 5T4, Canada
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9
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Wania F, Warner NA, McLachlan MS, Durham J, Miøen M, Lei YD, Xu S. Seasonal and latitudinal variability in the atmospheric concentrations of cyclic volatile methyl siloxanes in the Northern Hemisphere. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2023; 25:496-506. [PMID: 36826379 DOI: 10.1039/d2em00467d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Field data from two latitudinal transects in Europe and Canada were gathered to better characterize the atmospheric fate of three cyclic methylsiloxanes (cVMSs), i.e., octamethyl-cyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) and dodecamethylcyclohexasiloxane (D6). During a year-long, seasonally resolved outdoor air sampling campaign, passive samplers with an ultra-clean sorbent were deployed at 15 sampling sites covering latitudes ranging from the source regions (43.7-50.7 °N) to the Arctic (79-82.5 °N). For each site, one of two passive samplers and one of two field blanks were separately extracted and analyzed for the cVMSs at two different laboratories using gas-chromatography-mass spectrometry. Whereas the use of a particular batch of sorbent and the applied cleaning procedure to a large extent controlled the levels of cVMS in field blanks, and therefore also the method detection and quantification limits, minor site-specific differences in field blank contamination were apparent. Excellent agreement between duplicates was obtained, with 95% of the concentrations reported by the two laboratories falling within a factor of 1.6 of each other. Nearly all data show a monotonic relationship between the concentration and distance from the major source regions. Concentrations in source regions were comparatively constant throughout the year, while the concentration gradient towards remote regions became steeper during summer when removal via OH radicals is at its maximum. Concentrations of the different cVMS oligomers were highly correlated within a given transect. Changes in relative abundance of cVMS oligomers along the transect were in agreement with relative atmospheric degradation rates via OH radicals.
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Affiliation(s)
- Frank Wania
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario, M1C 1A4, Canada
- WECC Wania Environmental Chemists Corp., Toronto, Ontario, Canada
| | - Nicholas A Warner
- Norwegian Institute for Air Research, Fram Centre, Tromsø, NO-9296, Norway
| | - Michael S McLachlan
- Department of Environmental Science, Stockholm University, Stockholm, SE-106 91, Sweden
| | - Jeremy Durham
- Toxicology and Environmental Research and Consulting, Dow Chemical Company, 1803 Building, Washington Street, Midland, MI, 48674, USA.
| | - Merete Miøen
- Norwegian Institute for Air Research, Fram Centre, Tromsø, NO-9296, Norway
| | - Ying Duan Lei
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario, M1C 1A4, Canada
- WECC Wania Environmental Chemists Corp., Toronto, Ontario, Canada
| | - Shihe Xu
- Toxicology and Environmental Research and Consulting, Dow Chemical Company, 1803 Building, Washington Street, Midland, MI, 48674, USA.
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10
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Zhu Y, Tang Z, He Y, Wang F, Lyu Y. Occurrence of methylsiloxanes in indoor store dust in China and potential human exposure. ENVIRONMENTAL RESEARCH 2023; 218:114969. [PMID: 36455627 DOI: 10.1016/j.envres.2022.114969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 11/23/2022] [Accepted: 11/27/2022] [Indexed: 06/17/2023]
Abstract
Methylsiloxanes are synthetic molecules with versatile and extensive applications. Because of their volatile properties, they are easily released from manufactured products and contaminate indoor environments, causing high human exposure. However, available information on their presence in specific microenvironments, and on the related potential risks for human health, is limited. We conducted a survey of sixteen methylsiloxanes species, including three cyclic (D4-D6) and thirteen linear (L4-L16) chemicals, in indoor dust samples from twenty-eight stores representative of six store categories in Beijing, China. Total methylsiloxane concentrations in store dust were 176-54,825 ng/g, depending on the store, with a median of 2196 ng/g. Linear chemicals represented a median proportion of 90.8% of total methylsiloxanes. The measured methylsiloxane concentrations in this study were marginally higher than those reported previously for standard living and working environments. The highest linear and total methylsiloxane concentrations were measured in electronic stores, while the highest cyclic methylsiloxane concentrations were measured in department stores. The presence of methylsiloxanes in the store dust samples was attributed mainly to their release from chemical additives in marketed products. Estimated median total exposure doses under normal and worst-case exposure scenarios were 0.237 and 0.888 ng/kg bw/d, respectively. Further investigation is needed to characterize methylsiloxane distribution in other microenvironments and to evaluate the associated health risks.
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Affiliation(s)
- Yanhuan Zhu
- Key Laboratory of Ecology and Environment in Minority Areas, Minzu University of China, National Ethnic Affairs Commission, Beijing, 100081, China; College of Life and Environmental Sciences, Minzu University of China, Beijing, 100081, China.
| | - Zhenwu Tang
- Key Laboratory of Ecology and Environment in Minority Areas, Minzu University of China, National Ethnic Affairs Commission, Beijing, 100081, China; College of Life and Environmental Sciences, Minzu University of China, Beijing, 100081, China.
| | - Ying He
- Key Laboratory of Ecology and Environment in Minority Areas, Minzu University of China, National Ethnic Affairs Commission, Beijing, 100081, China; College of Life and Environmental Sciences, Minzu University of China, Beijing, 100081, China.
| | - Fei Wang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.
| | - Yang Lyu
- Key Laboratory of Ecology and Environment in Minority Areas, Minzu University of China, National Ethnic Affairs Commission, Beijing, 100081, China; College of Life and Environmental Sciences, Minzu University of China, Beijing, 100081, China.
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11
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Gerhards R, Seston RM, Kozerski GE, McNett DA, Boehmer T, Durham JA, Xu S. Basic considerations to minimize bias in collection and analysis of volatile methyl siloxanes in environmental samples. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 851:158275. [PMID: 36030859 DOI: 10.1016/j.scitotenv.2022.158275] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 08/17/2022] [Accepted: 08/21/2022] [Indexed: 06/15/2023]
Abstract
Monitoring studies that aim to quantify volatile methyl siloxanes (VMS) in environmental matrices may encounter a multitude of issues, most of which relate to the unique combination of physical-chemical characteristics of VMS that distinguish them from other classes of organic compounds. These properties, which are critical to their function in various applications, also control their fate and distribution in the environment, as well as the analytical chemistry of their measurement. Polycondensation and rearrangement reactions of VMS oligomers are possible during sample storage and analysis. Thus, care should be exercised to suppress these types of reactions by avoiding any catalytic substances or surfaces in sample collection and analysis equipment. Another factor complicating sample integrity in the analysis of trace levels of VMS, is their ubiquitous presence in many common products and components of instrumentation in the laboratory. For example, some gas chromatography columns and inlet septa have been identified as sources of VMS due to surface-catalyzed transformation of silicones to VMS promoted by moisture under high temperature in some silicone-based GC columns. Possible chemical transformation of the analytes, contamination from other sources, and potential loss of analytes need to be assessed throughout all aspects of the study, from sample collection through analysis, by establishing a rigorous quality assurance and quality control program. The implementation of such a robust QA/QC program facilitates the identification and minimization of potential analytical biases and ensures the validity and usability of data generated from environmental monitoring campaigns for VMS. The objective of this paper is to focus on aspects of collection, processing, and analysis of environmental samples that may influence the quality of the VMS analytical results. This information should then be employed in the design and implementation of future monitoring studies and can used to assess the validity of analytical results from VMS monitoring studies.
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Affiliation(s)
| | - Rita M Seston
- Hyla Environmental Consulting, LLC, Midland, MI 48640, USA.
| | - Gary E Kozerski
- Toxicology & Environment Research and Consulting (TERC), The Dow Chemical Company, Midland, MI 48674, USA
| | - Debra A McNett
- Toxicology & Environment Research and Consulting (TERC), The Dow Chemical Company, Midland, MI 48674, USA
| | - Thomas Boehmer
- Evonik Operations GmbH, Analytical Laboratory, 45127 Essen, Germany
| | - Jeremy A Durham
- Toxicology & Environment Research and Consulting (TERC), The Dow Chemical Company, Midland, MI 48674, USA
| | - Shihe Xu
- Toxicology & Environment Research and Consulting (TERC), The Dow Chemical Company, Midland, MI 48674, USA
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12
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Guo J, Zhou Y, Wang Y, Chen Y, Zhang B, Zhang J. Methylsiloxanes risk assessment combining external and internal exposure for college students. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 845:157379. [PMID: 35843336 DOI: 10.1016/j.scitotenv.2022.157379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 07/10/2022] [Accepted: 07/11/2022] [Indexed: 06/15/2023]
Abstract
Methylsiloxanes (MSs) are widely used as solvents or emollients in various personal care products (PCPs) and may pose a health risk. In this study, we assessed external and internal exposure to MSs among students at two universities in southwestern China. Samples of air, dust, and PCPs were collected to evaluate indoor non-dietary exposure to MSs via multiple pathways among the students. Indoor MS levels were approximately 1-3 orders of magnitude higher in the dormitories of female students than in either classrooms or the dormitories of male students. Lipstick contained the highest MS levels. Cyclic MS (CMS: D4-D6) levels were 1 order of magnitude higher in female students than in male students. Among the three CMSs, D5 levels were highest in the plasma of all students (1.3-15 ng/mL). In dormitories, dermal contact with PCPs was the major route of exposure to CMSs for all students. Among linear MSs (LMSs: L5-L16), dermal PCP absorption and dust ingestion were the predominant exposure routes for male and female students, respectively. Although the overall risk of exposure to D4 and D5 was below the chronic reference dose for all exposure routes and all students, the total daily doses of exposure to D4 and D5 via dermal PCP absorption approached the chronic reference dose in four female students. Therefore, the effects of MSs on female students should be further investigated in future studies.
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Affiliation(s)
- Junyu Guo
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China; State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.
| | - Ying Zhou
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Yifei Wang
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Yuan Chen
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Boya Zhang
- Department of Epidemiology, University of Michigan, Ann Arbor, MI, USA
| | - Jianbo Zhang
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
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13
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Jiang Y, Guo J, Zhou Y, Zhang B, Zhang J. Occurrence and Behavior of Methylsiloxanes in Urban Environment in Four Cities of China. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:13869. [PMID: 36360747 PMCID: PMC9658807 DOI: 10.3390/ijerph192113869] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 10/21/2022] [Accepted: 10/22/2022] [Indexed: 06/16/2023]
Abstract
Methylsiloxanes (MSs), used in industrial production and personal care products, are released in various environmental media. In this study, we combined monitoring and modeling to investigate the occurrence and behavior of MSs in the urban environment in China. MSs were widely found in the air, water, soil and sediment of four cities in China. The concentrations of MSs in all four environmental media of Zhangjiagang were higher than those in the other three cities (Beijing, Kunming and Lijiang), indicating that the siloxane production plant had a significant impact on the pollution level of MSs in the surrounding environment. The samples with high MS concentrations were all from the sample sites near the outlet of the WWTPs, which showed that the effluent of the WWTPs was the main source of MS pollution in the surrounding environment. The modeling results of the EQC level III model showed that D4 discharged into the environment was mainly distributed in the air, while D5 and D6 were mainly distributed in the sediment. CMSs (D4-D6) discharged into various environmental media could exist in the urban environment for a long time with low temperatures in cities. When the temperature was 0 °C, the residence time of D5 and D6 could be 68.1 days and 243 days in the whole environmental system in Beijing. This study illustrates the importance of CMSs (D4-D6) in low-temperature environments and the potential environmental risks that they may pose.
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Affiliation(s)
- Yao Jiang
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Junyu Guo
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Ying Zhou
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Boya Zhang
- Department of Epidemiology, University of Michigan, Ann Arbor, MI 48103, USA
| | - Jianbo Zhang
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
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14
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Zhang J, Liu N, Ren J, Xu L, Cai Y. Vinylmethylsiloxanes in Municipal Wastewater Treatment Plant and Biosolid-Amended Soils: Their Distribution and Backbone/Vinyl Branch Degradation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:10691-10698. [PMID: 35833964 DOI: 10.1021/acs.est.2c01400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
This study is the first to investigate the emission and environmental fate of one type of modified methylsiloxane with double-bond (vinyl) groups. During 2018-2020, 2,4,6-trimethyl-2,4,6-trivinylcyclotrisiloxane (V3), 2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane (V4), and 2,4,6,8,10-pentavinyl-2,4,6,8,10-pentamethylcyclopentasiloxane (V5) were found in aqueous (<LOD-72.9 ng/L) and solid [13.0-371 ng/g dw (dry weight)] phases of wastewater samples from one Chinese municipal wastewater treatment plant (WWTP) as well as the corresponding biosolid-amended soils [<LOD-36.9 ng/g dw, df (detection frequency) = 37.5-41.7%, n = 48]. Based on the measure of environmental samples, simulated experiment, and product analysis by ESI-FT-ICR-MS, it was found that (1) in addition to sorption to sludge, abiotic degradation of vinylmethylsiloxanes (especially V3, t1/2 = 0.5-1.9 h at pH = 5.2-9.2) should have an important contribution to their sufficient removal in WWTP; (2) different from siloxane analogues with saturated branches and aromatic branches, abiotic degradation pathways of vinylmethylsiloxane might include both the hydrolysis of Si-O backbone and the oxidation/addition reactions of vinyl branches; (3) although vinylmethylsiloxanes in wastewater could be transferred to soil by biosolids application, these compounds had no accumulation in soil, which should arise from their fast elimination, such as volatilization (t1/2 = 3.2 h-20.9 days) and degradation (t1/2 =9.1 h-96.3 days); and (4) degradation of the Si-O backbone and vinyl branches had slowing trends with the increase in the soil organic matter.
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Affiliation(s)
- Jie Zhang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Nannan Liu
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, China
| | - Juntao Ren
- Dongying Eco-Environment Monitoring Center of Shandong Province, Dongying 257091, China
| | - Lin Xu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- School of Environment, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 330106, China
| | - Yaqi Cai
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Hubei Key Laboratory of Environmental and Health Effects of Persistence Toxic Substances, Institute of Environment and Health, Jianghan University, Wuhan 430056, China
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15
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Alton MW, Browne EC. Atmospheric Degradation of Cyclic Volatile Methyl Siloxanes: Radical Chemistry and Oxidation Products. ACS ENVIRONMENTAL AU 2022; 2:263-274. [PMID: 37102141 PMCID: PMC10114625 DOI: 10.1021/acsenvironau.1c00043] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Cyclic volatile methyl siloxanes (cVMS) are anthropogenic chemicals that have come under scrutiny due to their widespread use and environmental persistence. Significant data on environmental concentrations and persistence of these chemicals exists, but their oxidation mechanism is poorly understood, preventing a comprehensive understanding of the environmental fate and impact of cVMS. We performed experiments in an environmental chamber to characterize the first-generation oxidation products of hexamethylcyclotrisiloxane (D3), octamethylcyclotetrasiloxane (D4), and decamethylcyclopentasiloxane (D5) under different peroxy radical fates (unimolecular reaction or bimolecular reaction with either NO or HO2) that approximate a range of atmospheric compositions. While the identity of the oxidation products from D3 changed as a function of the peroxy radical fate, the identity and yield of D4 and D5 oxidation products remained largely constant. We compare our results against the output from a kinetic model of cVMS oxidation chemistry. The reaction mechanism used in the model is developed using a combination of previously proposed cVMS oxidation reactions and standard atmospheric oxidation radical chemistry. We find that the model is unable to reproduce our measurements, particularly in the case of D4 and D5. The products that are poorly represented in the model help to identify possible branching points in the mechanism, which require further investigation. Additionally, we estimated the physical properties of the cVMS oxidation products using structure-activity relationships and found that they should not be significantly partitioned to organic or aqueous aerosol. The results suggest that cVMS first-generation oxidation products are also long-lived in the atmosphere and that environmental monitoring of these compounds is necessary to understand the environmental chemistry and loading of cVMS.
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Affiliation(s)
- Mitchell W. Alton
- Department of Chemistry, University of Colorado, Boulder, Colorado 80309, United States
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80309, United States
| | - Eleanor C. Browne
- Department of Chemistry, University of Colorado, Boulder, Colorado 80309, United States
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80309, United States
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16
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Whelan MJ, Kim J. Application of multimedia models for understanding the environmental behavior of volatile methylsiloxanes: Fate, transport, and bioaccumulation. INTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT 2022; 18:599-621. [PMID: 34375022 PMCID: PMC9293016 DOI: 10.1002/ieam.4507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 02/11/2021] [Accepted: 07/26/2021] [Indexed: 06/13/2023]
Abstract
Multimedia fate and transport models (MFTMs) describe how chemicals behave in the environment based on their inherent properties and the characteristics of receiving systems. We critically review the use of MFTMs for understanding the behavior of volatile methylsiloxanes (VMS). MFTMs have been used to predict the fate of VMS in wastewater treatment, rivers, lakes, marine systems, and the atmosphere, and to assess bioaccumulation and trophic transfers. More widely, they have been used to assess the overall persistence, long-range transport potential (LRTP), and the propensity for atmosphere-surface exchange. The application of MFTMs for VMS requires particularly careful selection of model inputs because the properties of VMS differ from those of most organic compounds. For example, although n-octanol/water partition coefficient (KOW ) values are high, air:water partition coefficient (KAW ) values are also high and n-octanol/air partition coefficient (KOA ) values are relatively low. In addition, organic carbon/water partition coefficient (KOC ) values are substantially lower than expectations based on KOW . This means that most empirical relationships between KOC and KOW are not appropriate. Good agreement between modeled and measured concentrations in air, sediment, and biota indicates that our understanding of environmental fate is reasonable. VMS compounds are "fliers" that principally partition to the atmosphere, implying high LRTP, although they have low redeposition potential. They are degraded in air (half-lives 3-10 days) and, thus, have low overall persistence. In water, exposure can be limited by hydrolysis, volatilization, and partitioning to sediments (where degradation half-lives are likely to be high). In food webs, they are influenced by metabolism in biota, which tends to drive trophic dilution (i.e., trophic magnification factors are often but not always <1). Key remaining uncertainties include the following: (i) the strength and direction of the temperature dependence for KOC ; (ii) the fate of atmospheric reaction products; and (iii) the magnitude of emissions to wastewater. Integr Environ Assess Manag 2022;18:599-621. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).
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Affiliation(s)
- Michael J. Whelan
- Centre for Landscape and Climate Research, School of Geography, Geology and the EnvironmentUniversity of LeicesterLeicesterUK
| | - Jaeshin Kim
- Toxicology and Environmental Research and ConsultingThe Dow Chemical CompanyMidlandMichiganUSA
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17
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Iacomi P, Gulcay-Ozcan E, Pires Conti P, Biswas S, Steunou N, Maurin G, Rioland G, Devautour-Vinot S. MIL-101(Cr) MOF as an Effective Siloxane Sensor. ACS APPLIED MATERIALS & INTERFACES 2022; 14:17531-17538. [PMID: 35380791 DOI: 10.1021/acsami.2c02607] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Volatile methylsiloxanes (VMSs) are common silicone degradation byproducts that cause serious concern for the contamination of sensitive electronics and optics, among others. With the goal of fast, online detection of VMS, we herein highlight the mesoporous MIL-101(Cr) MOF as a promising mass sensing layer for integration with a quartz crystal microbalance (QCM), using an in-house modified gravimetric adsorption system capable of achieving extremely low concentrations of siloxane D4 (down to 0.04 ppm), targeting applications for monitoring in indoor spaces and spacecraft. Our developed MIL-101(Cr)@QCM sensor achieves near-perfect reversibility with no hysteresis alongside excellent repeatability over cycling and fast response/recovery times under 1 min. We attribute this capability to optimum host/guest interactions as uncovered through molecular simulations.
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Affiliation(s)
- Paul Iacomi
- ICGM, Univ. Montpellier, CNRS, ENSCM, F-34095 Montpellier, France
| | | | | | - Subharanjan Biswas
- Institut Lavoisier de Versailles, UMR CNRS 8180, Université de Versailles St Quentin en Yvelines, Université Paris-Saclay, 78035 Versailles, France
| | - Nathalie Steunou
- Institut Lavoisier de Versailles, UMR CNRS 8180, Université de Versailles St Quentin en Yvelines, Université Paris-Saclay, 78035 Versailles, France
| | - Guillaume Maurin
- ICGM, Univ. Montpellier, CNRS, ENSCM, F-34095 Montpellier, France
| | - Guillaume Rioland
- Centre National d'Etudes Spatiales, DTN/QE/LE, 18 Avenue Edouard Belin, 31401 Toulouse, Cedex 09, France
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18
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Nguyen HMN, Khieu HT, Le HQ, Duong TT, Do TQ, Minh TB, Tran TM. Assessment of distributional characteristics and ecological risks of cyclic volatile methylsiloxanes in sediments from urban rivers in northern Vietnam. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:29917-29926. [PMID: 34994938 DOI: 10.1007/s11356-021-18487-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 12/30/2021] [Indexed: 06/14/2023]
Abstract
In this report, four cVMSs including hexamethylcyclotrisiloxane (D3), octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) were determined in 85 sediment samples collected from three rivers in northern Vietnam during the period from May to November 2020. Total mean concentrations of cVMSs ranged from 75.4 to 15,000 ng/g-dw. The highest levels of cVMS were found in sediment samples collected from the To Lich River (range, 260-15,000 ng/g-dw; median, 2840 ng/g-dw), followed by the Nhue River (range, 188-6800 ng/g-dw; median, 1370 ng/g-dw), and the Day River (range, 75.4-4600 ng/g-dw; median, 666 ng/g-dw). Among cVMSs, decamethylcyclopentasiloxane (D5) was found at the highest levels in all samples and ranged from 9.00 to 11,000 ng/g-dw. Significant correlations exist between the concentrations of D4/D6 and D5/D6 pairs in river sediment samples. Although the calculated ecological risk was not high, the presence of cVMSs in the sediment raises concerns about the impact on aquatic life because of their long-term accumulation capacity.
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Affiliation(s)
- Ha My Nu Nguyen
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi, 10000, Vietnam
- Ha Tinh University, Cam Vinh Commune, Cam Xuyen District, Ha Tinh, Vietnam
| | - Hanh Thi Khieu
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi, 10000, Vietnam
| | - Huong Quang Le
- Center for Research and Technology Transfer, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi, 10000, Vietnam
| | - Thi Thuy Duong
- Institute of Environmental Technology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi, 10000, Vietnam
| | - Trung Quang Do
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi, 10000, Vietnam
| | - Tu Binh Minh
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi, 10000, Vietnam
| | - Tri Manh Tran
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi, 10000, Vietnam.
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19
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Xu J, Harrison RM, Song C, Hou S, Wei L, Fu P, Li H, Li W, Shi Z. PM 2.5-bound silicon-containing secondary organic aerosols (Si-SOA) in Beijing ambient air. CHEMOSPHERE 2022; 288:132377. [PMID: 34600012 DOI: 10.1016/j.chemosphere.2021.132377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 09/15/2021] [Accepted: 09/25/2021] [Indexed: 06/13/2023]
Abstract
Volatile methyl siloxanes (VMS) have been widely used in personal care products and industrial applications, and are an important component of VOCs (volatile organic compounds) indoors. They have sufficiently long lifetimes to undergo long-range transport and to form secondary aerosols through atmospheric oxidation. To investigate these silicon-containing secondary organic aerosols (Si-SOA), we collected PM2.5 samples during 8th-21st August 2018 (summer) and 3rd-23rd January 2019 (winter) at an urban site of Beijing. As the oxidation of VMS mainly results in hydrophilic polar semi-volatile and non-volatile oxidation products, the differences between total water-soluble Si and total water-soluble inorganic Si were used to estimate water-soluble organic Si, considered to be secondary organic Si (SO-Si). The average concentrations of SO-Si during the summer and winter campaigns were 4.6 ± 3.7 and 13.2 ± 8.6 ng m-3, accounting for approximately 80.1 ± 10.1% and 80.2 ± 8.7% of the total water-soluble Si, and 1.2 ± 1.2% and 5.0 ± 6.9% of total Si in PM2.5, respectively. The estimated Si-SOA concentrations were 12.7 ± 10.2 ng m-3 and 36.6 ± 23.9 ng m-3 on average in summer and winter, which accounted for 0.06 ± 0.07% and 0.16 ± 0.22% of PM2.5 mass, but increased to 0.26% and 0.92% on certain days. We found that net solar radiation is positively correlated with SO-Si levels in the summer but not in winter, suggesting seasonally different formation mechanisms.
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Affiliation(s)
- Jingsha Xu
- School of Geography Earth and Environmental Science, University of Birmingham, Birmingham, B15 2TT, UK; Department of Chemistry, University of Warwick, Coventry, CV4 7AL, UK.
| | - Roy M Harrison
- School of Geography Earth and Environmental Science, University of Birmingham, Birmingham, B15 2TT, UK; Department of Environmental Sciences/Center of Excellence in Environmental Studies, King Abdulaziz University, P.O. Box 80203, Jeddah, 21589, Saudi Arabia
| | - Congbo Song
- School of Geography Earth and Environmental Science, University of Birmingham, Birmingham, B15 2TT, UK
| | - Siqi Hou
- School of Geography Earth and Environmental Science, University of Birmingham, Birmingham, B15 2TT, UK
| | - Lianfang Wei
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, 100029, China
| | - Pingqing Fu
- Institute of Surface-Earth System Science, Tianjin University, Tianjin, 300072, China
| | - Hong Li
- Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Weijun Li
- Department of Earth and Atmospheric Sciences, Zhejiang University, Hangzhou, 310027, China
| | - Zongbo Shi
- School of Geography Earth and Environmental Science, University of Birmingham, Birmingham, B15 2TT, UK.
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20
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Xu S, Vogel A. Measuring snow scavenging of two airborne cyclic volatile methylsiloxanes under controlled conditions. CHEMOSPHERE 2021; 285:131291. [PMID: 34252803 DOI: 10.1016/j.chemosphere.2021.131291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 06/15/2021] [Accepted: 06/17/2021] [Indexed: 06/13/2023]
Abstract
The objective of this study was to determine snow scavenging of cVMS and its potential effect on the cVMS concentrations in snowmelt water and surrounding soil. Snow scavenging of two cVMS, octamethylcyclotetrasiloxane (D4) and decamethylcyclopentasiloxane (D5), was examined in two steps. First, sorption and desorption of D4 and D5 on snowflakes, including snow sorption coefficients (KiA), were measured against a benchmark compound, cyclopentanone, at different temperatures from 0 to -20 °C. Measurements were made using a custom-made snow chamber and 14C-labeled D4 and D5. In addition, the transfer of snow-bound cVMS to snowmelt water and surrounding soil was studied with 14C-D4 and 14C-D5-spiked snowpack placed both in a closed snow chamber and on top of a layer of frozen soil in an open chemical hood. KiA values measured in both sorption and desorption processes were very small (<10-2 m). They increased with decreasing temperature and were higher for the D5 compared to D4. The calculated gas scavenging of D4 and D5 was small because of the small KiA values, while particle scavenging of cVMS is predicted to be negligible due to their low octanol/air partition coefficients (KOA). Most importantly, almost all 14C-D4 and 14C-D5 sorbed by a snowpack was lost during the snow melting process through re-volatilization and hydrolysis and became non-detectable in snowmelt water. In short, the experimental measurements demonstrated that snow scavenging could not be a valid deposition mechanism for these volatile hydrophobic compounds.
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Affiliation(s)
- Shihe Xu
- Toxicology and Environmental Research and Consulting (TERC), Dow Chemical Company, Midland, MI, 48674, USA.
| | - Annette Vogel
- Toxicology and Environmental Research and Consulting (TERC), Dow Chemical Company, Midland, MI, 48674, USA
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21
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Meng T, Su S, Cheng J, Zhong F, Tang Z. Methylsiloxanes in street dust from Hefei, China: Distribution, sources, and human exposure. ENVIRONMENTAL RESEARCH 2021; 201:111513. [PMID: 34166660 DOI: 10.1016/j.envres.2021.111513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 06/07/2021] [Accepted: 06/08/2021] [Indexed: 06/13/2023]
Abstract
Methylsiloxanes are widely found in the environment and have been of increasing concern because of their strong resistance to degradation and potential toxicity to organisms. However, little is known about the distributions of these chemicals in street dust and the associated human health risks. This study investigated three cyclic (D4-D6) and nine linear methylsiloxanes (L5-L13) in street dust from Hefei, China and found total concentrations in the range of 183-1030 (median, 527) ng/g dry weight. The linear congeners were dominant and represented a median of 85.3% of the total methylsiloxanes. D5 contributed 90.0% of the total concentrations of cyclic methylsiloxanes. In this study, higher concentrations of dust methylsiloxanes were found in the industrial area relative to the other functional areas. A source assessment indicated that the linear and cyclic methylsiloxanes in the street dust were mainly from the industrial and traffic activities, respectively, in addition to important sources of the use of siloxanes-containing products. The estimated median daily intakes of total methylsiloxanes through street dust were 0.037 and 0.476 ng/kg-bw/d for adults and children, respectively, under high-exposure scenarios. More research is needed to characterize the occurrence of methylsiloxane in various exposure sources and the associated adverse effects on human health.
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Affiliation(s)
- Tong Meng
- College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, China.
| | - Shuai Su
- College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, China.
| | - Jiali Cheng
- National Institute for Nutrition and Health, Chinese Center for Disease Control and Prevention, Beijing, 100050, China.
| | - Fuyong Zhong
- College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, China.
| | - Zhenwu Tang
- College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, China; College of Life and Environmental Sciences, Minzu University of China, Beijing, 100081, China.
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22
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Cheng J, Tang Z, Ma Y, Yin H, Meng T, Sun J. Methyl siloxanes in soils from a large silicone-manufacturing site, China: concentrations, distributions and potential human exposure. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2021; 43:3871-3881. [PMID: 33710420 DOI: 10.1007/s10653-021-00873-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Accepted: 02/27/2021] [Indexed: 06/12/2023]
Abstract
Methyl siloxanes are widely found in the environment, but little is known about the distributions of these chemicals in soils especially in areas where they are manufactured. We determined the concentrations of four cyclic (D3-D6) and 13 linear methyl siloxanes (L4-L16) in the soils from a siloxane-manufacturing site in China; the total concentrations of these 17 siloxanes (TSi) in the soils were 17.1-3,191 (median, 134) ng/g. We did not find extremely high concentrations of siloxanes in the soils. The median concentrations of total cyclic siloxanes (TCSi) were approximately sevenfold higher than those of total linear congeners. Hexamethylcyclotrisiloxane and octamethylcyclotetrasiloxane contributed a median of 59.7% and 20.3% of the TSi concentrations, respectively. Higher concentrations of soil TCSi were found in the silicone-manufacturing area relative to the other study areas. Source analysis indicated that industrial activities contributed substantially to soil siloxanes, in addition to the contribution of the siloxane emissions from specific consumer products. We calculated that the median values of daily TSi intakes through soil ingestion were 0.021 and 0.138 ng/kg-body weight/day for adults and children, respectively, under high exposure scenarios. Although our estimated daily intakes of the chemicals from soils were low, more research is required to improve our understanding of the health risks posed to humans exposed to siloxanes through other pathways.
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Affiliation(s)
- Jiali Cheng
- National Institute for Nutrition and Health, Chinese Center for Disease Control and Prevention, Beijing, 100050, China
| | - Zhenwu Tang
- College of Life and Environmental Sciences, Minzu University of China, Beijing, 100081, China.
- College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, China.
| | - Yan Ma
- National Institute for Nutrition and Health, Chinese Center for Disease Control and Prevention, Beijing, 100050, China
| | - Hongmin Yin
- College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, China
| | - Tong Meng
- College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, China
| | - Jiazheng Sun
- College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, China
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23
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Nu Nguyen HM, Khieu HT, Ta NA, Le HQ, Nguyen TQ, Do TQ, Hoang AQ, Kannan K, Tran TM. Distribution of cyclic volatile methylsiloxanes in drinking water, tap water, surface water, and wastewater in Hanoi, Vietnam. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 285:117260. [PMID: 33964558 DOI: 10.1016/j.envpol.2021.117260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 04/23/2021] [Accepted: 04/24/2021] [Indexed: 06/12/2023]
Abstract
In this study, four cyclic volatile methylsiloxanes (cVMSs) were determined in drinking water, tap water, surface water, and wastewater samples collected from Hanoi metropolitan area, Vietnam, during August to December 2020 (dry season) by using solid phase extraction combined with gas chromatography tandem mass spectrometry. Highest concentrations of cVMSs in the range of 63-7400 ng/L (mean/median: 1840/1310 ng/L) were found in wastewater samples. A significant difference existed in the concentrations of cVMSs between influent and effluent of a wastewater treatment plant. The sum concentrations of four cVMSs in lake water, tap water, and bottled water samples were in the ranges of 67.0-1100 ng/L (mean/median: 350/282 ng/L), 19.8-350 ng/L (12.6/12.3 ng/L), and 2.31-28.1 ng/L (10.3/8.23 ng/L), respectively. Among the four cVMSs, decamethylcyclopentasiloxane (D5) was found at the highest concentrations in all water samples analyzed. The mean exposure doses of cVMSs calculated for adults and children through the consumption of drinking were 0.409 and 0.412 ng/kg-bw/day, respectively. Human exposure to cVMSs calculated through drinking water consumption was significantly lower than that reported for inhalation.
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Affiliation(s)
- Ha My Nu Nguyen
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi, 10000, Viet Nam; Ha Tinh University, Cam Vinh Commune, Cam Xuyen District, Ha Tinh, 45000, Viet Nam
| | - Hanh Thi Khieu
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi, 10000, Viet Nam
| | - Ngoc Anh Ta
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi, 10000, Viet Nam
| | - Huong Quang Le
- Center for Research and Technology Transfer, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi, 10000, Viet Nam
| | - Trung Quang Nguyen
- Center for Research and Technology Transfer, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi, 10000, Viet Nam
| | - Trung Quang Do
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi, 10000, Viet Nam
| | - Anh Quoc Hoang
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi, 10000, Viet Nam; Center of Advanced Technology for the Environment (CATE), Graduate School of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama, 790-8566, Japan
| | - Kurunthachalam Kannan
- Department of Pediatrics and Department of Environmental Medicine, New York University School of Medicine, New York, NY, 10016, USA
| | - Tri Manh Tran
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi, 10000, Viet Nam.
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Guo J, Zhou Y, Wang Y, Zhang B, Zhang J. Assessment of internal exposure to methylsiloxanes in children and associated non-dietary exposure risk. ENVIRONMENT INTERNATIONAL 2021; 154:106672. [PMID: 34062401 DOI: 10.1016/j.envint.2021.106672] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 04/26/2021] [Accepted: 05/24/2021] [Indexed: 06/12/2023]
Abstract
Methylsiloxanes (MSs) are a significant source of indoor environmental pollution due to their high production level and widespread application, and pose a potential health risk. Given the special vulnerability of children to environmental contaminants, assessment of indoor MSs exposure in children is quite essential. In this study, we assessed internal exposure doses and external exposure levels of MSs in children from industrial and residential areas in southwestern China. Indoor air, indoor dust, and personal care product (PCP) samples were collected to evaluate indoor non-dietary MSs exposure in children through various pathways. The concentrations of MSs in indoor environments of industrial areas were approximately one to four orders of magnitude higher than those of residential areas. Sun protection products contained the highest concentrations of MSs. Relatively high levels of cyclic methylsiloxanes (CMSs) were found in plasma of children from industrial areas, which were one to two orders of magnitude higher than those in children from residential areas. The highest MSs levels in plasma were detected in infants (0-1 year), with values of 1.4 × 102 ng/mL and 1.3 × 102 ng/mL for CMSs (D4-D6) and linear methylsiloxanes (LMSs) (L5-L16), respectively. The internal exposure dose of infants in residential areas is driven by major unknown sources of MSs. The average daily doses via inhalation and dust ingestion in children from industrial areas were one to three orders of magnitude higher than in those from residential areas, indicating that these children should be considered a highly exposed population. Inhalation and dust ingestion were both major exposure pathways to MSs for children of all age groups in industrial areas, whereas dermal absorption from PCPs was the predominant exposure pathway for children of all age groups in residential areas (except for infants). Although the exposure risk to D4 and D5 was at an acceptable level for all children studied, the total daily exposure doses of these two cyclic compounds via inhalation for infants in the industrial areas was near the chronic reference dose. Meanwhile, MSs may accumulate in infant plasma within a short period of time (<6 months). Therefore, infants should be the focus of greater attention in future research. As indoor environments may pose high risks for infants in industrial areas, they should be the focus of future research.
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Affiliation(s)
- Junyu Guo
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.
| | - Ying Zhou
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Yifei Wang
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Boya Zhang
- Department of Epidemiology, University of Michigan, Ann Arbor, MI, USA
| | - Jianbo Zhang
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.
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25
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Xiang X, Liu N, Xu L, Cai Y. Review of recent findings on occurrence and fates of siloxanes in environmental compartments. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 224:112631. [PMID: 34416634 DOI: 10.1016/j.ecoenv.2021.112631] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 08/08/2021] [Accepted: 08/10/2021] [Indexed: 06/13/2023]
Abstract
In view of their vast global usage in both consumer products and industrial processes, environmental emission and fates of siloxanes have become concerned issue. This review summarized the research progress, especially in the last decade, on production/consumption data, toxicities, analysis methods, environmental distribution, migration and degradation/transformation of both dimethylsiloxanes and modified siloxanes in atmospheric, aquatic and terrestrial compartments from various areas (especially in China). In spite of their fast degradation (hydrolysis and hydroxylation, etc) in various matrices (except sediment), dimethylsiloxane oligomers have been found in various environmental matrices from many countries due to their constant usage and emission. Moreover, recent literatures have paid attention to behaviors of dimethylsiloxanes in industrial areas, e.g., their higher residual levels compared with residential areas and unique transformed products (such as halogenated products) arose from special industrial production scenarios. Meanwhile, although most prior studies focused on dimethylsiloxanes, identification of modified-siloxanes with other functional groups in environment have been beginning to attract the attention of scientists. Furthermore, related literatures indicated that compared with dimethylsiloxanes, both halogenated-dimethylsiloxanes and modified methylsiloxanes (phenylsiloxanes and trifluoropropylsiloxanes) could have stronger persistence due to their weaker volatilization and degradation, especially in terrestrial matrices.
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Affiliation(s)
- Xiaoling Xiang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Hubei Key Laboratory of Environmental and Health Effects of Persistence Toxic Substances, Institute of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Nannan Liu
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, China
| | - Lin Xu
- School of Environment, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 330106, China.
| | - Yaqi Cai
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Hubei Key Laboratory of Environmental and Health Effects of Persistence Toxic Substances, Institute of Environment and Health, Jianghan University, Wuhan 430056, China; School of Environment, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 330106, China
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26
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Liu N, Sun H, Xu L, Cai Y. Methylsiloxanes in petroleum refinery facility: Their sources, emissions, environmental distributions and occupational exposure. ENVIRONMENT INTERNATIONAL 2021; 152:106471. [PMID: 33676090 DOI: 10.1016/j.envint.2021.106471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 02/13/2021] [Accepted: 02/15/2021] [Indexed: 06/12/2023]
Abstract
High concentrations (1.08 ng/g-3.61 mg/g) of methylsiloxanes, including cyclic analogs [octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) and dodecamethylcyclohexasiloxane (D6)], and linear analogs with 3-14 silicon atoms (L3-L14), have been detected in crude oil, additives and petroleum products from one petroleum refinery facility in China. Overall, the total mass load of Σmethylsiloxanes (1320 kg/day) in crude oil and additives was 1.5 times higher than that in petroleum products (857 kg/day), indicating their potential emissions in this facility, which were further confirmed by the find of their obvious emission through exhaust-gas (89.4 kg/day) and wastewater (4.70 kg/day). Σmethylsiloxanes emission from exhaust-gas discharge outlets of deep catalytic cracking units (60.6 kg/day) took up 68% of their total emission from all gas outlets. Overall, Σmethylsiloxanes in air (17.1-743 μg/m3) and soil samples [311 ng/g dw (dry weight) - 34.2 μg/g dw] from this facility were up to four orders of magnitude greater than those from surrounding areas, and plasma concentrations of Σmethylsiloxanes in current workers from this facility (7.4-609 ng/mL) were up to two orders of magnitude larger than those from reference group (<LOQ-21.2 ng/mL). Furthermore, concentration ratios (0.09-0.58) of total cyclic methylsiloxanes to their hepatic metabolites for workers were 2.3-17 times lower than those (1.32-1.56) for reference group, indicating that refinery workers may be exposed to more unknown methylsiloxane analogs than general population.
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Affiliation(s)
- Nannan Liu
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Science, Chinese Academy of Sciences, Beijing 100085, China
| | - Hongyu Sun
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, China; Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria, Nankai University, Tianjin 300350, China; Joint Research Centre for Protective Infrastructure Technology and Environmental Green Bioprocess, Tianjin 300384, China
| | - Lin Xu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Science, Chinese Academy of Sciences, Beijing 100085, China.
| | - Yaqi Cai
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Science, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
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27
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Okan F, Odabasi M, Yaman B, Dumanoglu Y. Development of a New Passive Sampling Method for the Measurement of Atmospheric Linear and Cyclic Volatile Methyl Siloxanes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:4522-4531. [PMID: 33769040 DOI: 10.1021/acs.est.1c00227] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
A new passive sampling method was developed and characterized to measure atmospheric volatile methyl siloxanes (VMS). The infrastructure of a commercial passive air sampler (PAS) was used along with XAD-2 resin as the adsorbent. Experimental sampling rates (SR) determined using collocated active and passive samplers ranged between 0.0363 (L5) and 0.0561 (D3) m3/day and agreed well with the theoretical ones. VMS uptake was highly linear for eight weeks. The precision of the method was very good (<10%). Compared to the other PASs used for VMS, the new method has several advantages (i.e., the sampler is much smaller, it has commercially available components, and the solvent requirement, equipment needed for extraction, and steps for sample preparation are minimal) while achieving similar or lower method detection limits. The developed method was applied to investigate the spatial distribution and possible sources of atmospheric VMS in the Izmir region. Field sampling covered 42 sites representing different source and land use areas. ΣVMS concentrations ranged between 41.4 and 981 ng/m3. The dominant VMS was D5 followed by D3 and D4. Spatial distributions indicated that the main VMS sources in the area were urban areas, wastewater treatment plants, and landfills where the VMS-containing products are used and disposed.
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Affiliation(s)
- Fulya Okan
- Department of Environmental Engineering, Dokuz Eylul University, Tinaztepe Campus, Buca, Izmir 35160, Turkey
| | - Mustafa Odabasi
- Department of Environmental Engineering, Dokuz Eylul University, Tinaztepe Campus, Buca, Izmir 35160, Turkey
| | - Baris Yaman
- Department of Environmental Engineering, Dokuz Eylul University, Tinaztepe Campus, Buca, Izmir 35160, Turkey
| | - Yetkin Dumanoglu
- Department of Environmental Engineering, Dokuz Eylul University, Tinaztepe Campus, Buca, Izmir 35160, Turkey
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28
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Anh HQ, Nguyen HMN, Do TQ, Tran KQ, Minh TB, Tran TM. Air pollution caused by phthalates and cyclic siloxanes in Hanoi, Vietnam: Levels, distribution characteristics, and implications for inhalation exposure. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 760:143380. [PMID: 33183807 DOI: 10.1016/j.scitotenv.2020.143380] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 10/20/2020] [Accepted: 10/21/2020] [Indexed: 06/11/2023]
Abstract
Contamination status and distribution characteristics of ten phthalic acid esters (PAEs) and three cyclic volatile methyl siloxanes (CSs) were determined in the air (gas and particle) samples collected from indoor and outdoor spaces of several chemistry laboratories, offices, and homes from urban area of Hanoi, the capital city of Vietnam. Air concentrations of Σ10PAEs (median 688; range 142-2390 ng m-3) and Σ3CSs (171; not detected-1100 ng m-3) in the indoor air samples were significantly higher than those measured in the outdoor ones (Σ10PAEs: 161; 34.1-515 ng m-3 and Σ3CSs: 43.2; not detected-258 ng m-3), partly suggesting the predominance of indoor emission sources of these substances. There were significant positive correlations in total air concentrations of phthalates and siloxanes between the indoor and outdoor air samples. The most predominant phthalates were diethyl-, di-n-butyl-, diisobutyl-, and di(2-ethylhexyl) phthalate. For siloxanes, D5 and D6 were more abundant than D4 in most samples. Except for di(2-ethylhexyl)- and di-n-octyl phthalate in some locations, almost all the compounds were likely associated with gas phase than particle phase. Daily intake doses of airborne phthalates and siloxanes, and non-cancer and cancer risks of selected phthalates were estimated for different exposure groups such as adults, children, and university subjects (e.g., laboratory staff and students), indicating relatively low levels of risk.
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Affiliation(s)
- Hoang Quoc Anh
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi 10000, Viet Nam; Center of Advanced Technology for the Environment (CATE), Graduate School of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama 790-8566, Japan
| | - Ha My Nu Nguyen
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi 10000, Viet Nam; Ha Tinh University, Cam Vinh commune, Cam Xuyen district, Ha Tinh 45000, Viet Nam
| | - Trung Quang Do
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi 10000, Viet Nam
| | - Khiem Quang Tran
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi 10000, Viet Nam
| | - Tu Binh Minh
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi 10000, Viet Nam
| | - Tri Manh Tran
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi 10000, Viet Nam.
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29
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Horii Y, Ohtsuka N, Minomo K, Takemine S, Motegi M, Hara M. Distribution characteristics of methylsiloxanes in atmospheric environment of Saitama, Japan: Diurnal and seasonal variations and emission source apportionment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 754:142399. [PMID: 33254939 DOI: 10.1016/j.scitotenv.2020.142399] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 08/27/2020] [Accepted: 09/13/2020] [Indexed: 06/12/2023]
Abstract
The large production volume of methylsiloxanes (MSs), combined with their high mobility/volatility and persistence, is a matter of concern from the atmospheric pollution perspective. Therefore, we evaluated of the concentrations and emission sources of MSs, including 7 cyclic methylsiloxanes (D3-D9; CMSs, the number refers to the number of Si-O bonds) and 13 linear methylsiloxanes (L3-L15; LMSs) in ambient air collected from Saitama, Japan. This is a first study regarding the evaluation of 20 methylsiloxanes in the Japanese atmosphere. We improved the air sampling methodology by determination the stability of D5 during a 7-d air sampling and arbitrary sample storage period using polystyrene-divinyl benzene copolymer sorbent (Sep-Pak plus PS-2). We analyzed air samples for MSs seasonally collected from nine locations in Saitama, including urban, suburban, rural, and mountainous areas. The mean CMS and LMS concentrations were 358 ng m-3 and 13.4 ng m-3, respectively. The D5 concentrations were distributed widely, with high concentrations in urban/suburban populous areas and dispersed at low concentrations in surrounding areas (north and mountainous areas). We analyzed 7-d air samples collected every week over a year and found apparent seasonal and periodic trends in the CMS concentrations. In the diurnal sampling campaign, we observed periodic fluctuations in ambient CMSs, with an inverse relationship with the atmospheric boundary layer development during the day. Backward trajectories and the prevailing wind direction during the sampling period indicated that the specific profiles of D4 observed in fall/winter weeks and north of Saitama could be ascribed to northwestward air-mass advection. We employed a novel approach in estimating CMSs emission sources and source apportionment by using non-negative matrix factorization (NMF). The concentration matrix was divided successfully into two factors (emission sources) namely, personal care and household products and industrial activities.
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Affiliation(s)
- Yuichi Horii
- Center for Environmental Science in Saitama, 914 Kamitanadare, Kazo, Saitama 347-0115, Japan.
| | - Nobutoshi Ohtsuka
- Center for Environmental Science in Saitama, 914 Kamitanadare, Kazo, Saitama 347-0115, Japan
| | - Kotaro Minomo
- Center for Environmental Science in Saitama, 914 Kamitanadare, Kazo, Saitama 347-0115, Japan
| | - Shusuke Takemine
- Center for Environmental Science in Saitama, 914 Kamitanadare, Kazo, Saitama 347-0115, Japan
| | - Mamoru Motegi
- Center for Environmental Science in Saitama, 914 Kamitanadare, Kazo, Saitama 347-0115, Japan
| | - Masayuki Hara
- Center for Environmental Science in Saitama, 914 Kamitanadare, Kazo, Saitama 347-0115, Japan
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30
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Li Q, Lan Y, Liu Z, Wang X, Wang X, Hu J, Geng H. Cyclic volatile methylsiloxanes (cVMSs) in the air of the wastewater treatment plants in Dalian, China - Levels, emissions, and trends. CHEMOSPHERE 2020; 256:127064. [PMID: 32454352 DOI: 10.1016/j.chemosphere.2020.127064] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 05/08/2020] [Accepted: 05/11/2020] [Indexed: 06/11/2023]
Abstract
Passive air samplers comprising sorbent-Tenax-TA thermal desorption tubes were applied for monitoring cyclic volatile methyl siloxanes (cVMSs) in the air above the aeration tanks of eight wastewater treatment plants (WWTPs, including five "open" and three "close" plants) in Dalian, China. The aim was to investigate the inputs of cVMSs from WWTPs to the air throughout a year (June 2016-July 2017). The ∑cVMS concentrations were averaged at 3.14 ± 6.84 μg·m-³ with D5 as the dominant compound (contributing to 63.8% of the ∑cVMS concentration). The annual average concentrations of D4, D5, and D6 in the air of the "close" WWTPs were 5.33 ± 4.63, 13.4 ± 14.4, and 1.05 ± 1.47 μg·m-³, and 1.31 ± 1.29, 1.57 ± 2.01, and 0.301 ± 0.340 μg·m-³ in the air from the "open" WWTPs, respectively. For both the close and open aeration tanks, the concentration of ∑cVMSs was the highest in summer and the lowest in winter, showing a significant correlation with ambient temperature (linear regression; p < 0.01). A simplified Gaussian dispersion model and a single chamber model were introduced to estimate annual emissions (kg·yr-1) of cVMSs from "open" and "close" WWTPs, ranging from 86.9 to 165 kg yr-1 and from 203 to 278 kg yr-1, respectively. Examining the relationship between the per capita emissions of cVMSs and average property prices, our results indicated that a greater amount of personal care products were used/discharged by people with relatively higher socioeconomic status.
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Affiliation(s)
- Qingbo Li
- College of Environmental Science and Engineering, Dalian Maritime University, Dalian, 116026, China.
| | - Yongchao Lan
- College of Environmental Science and Engineering, Dalian Maritime University, Dalian, 116026, China
| | - Zhongyi Liu
- College of Environmental Science and Engineering, Dalian Maritime University, Dalian, 116026, China
| | - Xianyu Wang
- Queensland Alliance for Environmental Health Sciences, The University of Queensland, 20 Cornwall Street, Woolloongabba, Queensland, 4102, Australia
| | - Xiaofeng Wang
- College of Environmental Science and Engineering, Dalian Maritime University, Dalian, 116026, China.
| | - Jiaochan Hu
- College of Environmental Science and Engineering, Dalian Maritime University, Dalian, 116026, China
| | - Hong Geng
- China Academy of Transportation Sciences, Beijing, 100029, China
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Martellini T, Berlangieri C, Dei L, Carretti E, Santini S, Barone A, Cincinelli A. Indoor levels of volatile organic compounds at Florentine museum environments in Italy. INDOOR AIR 2020; 30:900-913. [PMID: 32090381 DOI: 10.1111/ina.12659] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 01/28/2020] [Accepted: 02/16/2020] [Indexed: 06/10/2023]
Abstract
Indoor Air Quality monitoring in cultural institutions is of particular concern to protect these places and the cultural heritage content. An indoor monitoring campaign was performed in three museums in Florence (Italy) to determine the occurrence and levels of volatile organic compounds (VOCs). VOCs of interest included BTEX (benzene, toluene, ethylbenzene, xylenes), terpenes, aldehydes, organic acids, and cyclic volatile methyl siloxanes (cVMS). The most abundant VOCs in all samples analyzed were BTEX, which were strictly related to the traffic source, followed by siloxanes and terpenes. Among BTEX, toluene was always the most abundant followed by xylenes, ethylbenzene, and benzene. cVMS in exhibition rooms with the presence of visitors showed higher values compared to samples collected when the museums were closed. Terpenes showed not only the influence of vegetation-biogenic sources surrounding a museum but could also be related to the wood used for the construction of showcases and furniture and the use of cleaning products. Data obtained also showed the presence of organic acids and aldehydes whose source can be traced back to exhibits themselves and wood-based furniture. Assessing the levels of organic acids in museums is important because, over time, it can cause deterioration of the artifacts.
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Affiliation(s)
- Tania Martellini
- Department of Chemistry "Ugo Schiff", University of Florence, Florence, Italy
| | - Chiara Berlangieri
- Department of Chemistry "Ugo Schiff", University of Florence, Florence, Italy
- Center for Colloid and Surface Science (CSGI), University of Florence, Florence, Italy
| | - Luigi Dei
- Department of Chemistry "Ugo Schiff", University of Florence, Florence, Italy
- Center for Colloid and Surface Science (CSGI), University of Florence, Florence, Italy
| | - Emiliano Carretti
- Department of Chemistry "Ugo Schiff", University of Florence, Florence, Italy
- Center for Colloid and Surface Science (CSGI), University of Florence, Florence, Italy
| | - Saul Santini
- Department of Chemistry "Ugo Schiff", University of Florence, Florence, Italy
| | - Angelica Barone
- Department of Chemistry "Ugo Schiff", University of Florence, Florence, Italy
| | - Alessandra Cincinelli
- Department of Chemistry "Ugo Schiff", University of Florence, Florence, Italy
- Center for Colloid and Surface Science (CSGI), University of Florence, Florence, Italy
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Fu Z, Xie HB, Elm J, Guo X, Fu Z, Chen J. Formation of Low-Volatile Products and Unexpected High Formaldehyde Yield from the Atmospheric Oxidation of Methylsiloxanes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:7136-7145. [PMID: 32401014 DOI: 10.1021/acs.est.0c01090] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
With stricter regulation of atmospheric volatile organic compounds (VOCs) originating from fossil fuel-based vehicles and industries, the use of volatile chemical products (VCPs) and the transformation mechanism of VCPs have become increasingly important to quantify air quality. Volatile methylsiloxanes (VMS) are an important class of VCPs and high-production chemicals. Using quantum chemical calculations and kinetics modeling, we investigated the reaction mechanism of peroxy radicals of VMS, which are key intermediates in determining the atmospheric chemistry of VMS. L2-RSiCH2O2• and D3-RSiCH2O2• derived from hexamethyldisiloxane and hexamethylcyclotrisiloxane, respectively, were selected as representative model systems. The results indicated that L2-RSiCH2O2• and D3-RSiCH2O2• follow a novel Si-C-O rearrangement-driven autoxidation mechanism, leading to the formation of low volatile silanols and high yield of formaldehyde at low NO/HO2• conditions. At high NO/HO2• conditions, L2-RSiCH2O2• and D3-RSiCH2O2• react with NO/HO2• to form organic nitrate, hydroperoxide, and active alkoxy radicals. The alkoxy radicals further follow a Si-C-O rearrangement step to finally form formate esters. The novel Si-C-O rearrangement mechanism of both peroxy and alkoxy radicals are supported by available experimental studies on the oxidation of VMS. Notably, the high yield of formaldehyde is estimated to significantly contribute to formaldehyde pollution in the indoor environment, especially during indoor cleaning.
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Affiliation(s)
- Zihao Fu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Hong-Bin Xie
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Jonas Elm
- Department of Chemistry and iClimate, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark
| | - Xirui Guo
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Zhiqiang Fu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
- Division of Analytical and Environmental Toxicology, Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta T6G2R3, Canada
| | - Jingwen Chen
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
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Li Q, Lv X, Wang X, Hu J, Wang X, Ma J. Typical indoor concentrations and mass flow of cyclic volatile methylsiloxanes (cVMSs) in Dalian, China. CHEMOSPHERE 2020; 248:126020. [PMID: 32041064 DOI: 10.1016/j.chemosphere.2020.126020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 01/16/2020] [Accepted: 01/23/2020] [Indexed: 06/10/2023]
Abstract
Cyclic volatile methylsiloxaes (cVMSs), namely hexamethylcyclotrisiloxane (D3), octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) and dodecamethylcyclohexasiloxane (D6), were studied for a typical indoor environment of male and female dormitories in the campus of Dalian Maritime University (DMU) in China. An empty, frit-fitted SPE cartridge was placed on top of an Isolute ENV + cartridge, sampling cVMSs in particulate and gas phases, respectively. The highest concentration of D3, D4, D5, and D6 was 190, 460, 37,000, and 670 ng m-3, respectively. All cVMSs, especially D5, were higher in female dormitories than that in male dormitories. Emission rate from different sources of cVMSs in dormitories was calculated from a survey of the use of personal care products (PCPs) by students living in the dormitory during the sampling period. The mean emission rate (ER, mg·d-1) of D4 and D5 in male dormitories was 0.12 ± 0.01 and 0.49 ± 0.03 mg d-1, respectively, and that in female dormitories was 0.21 ± 0.05 and 46 ± 17 mg d-1, respectively. Then, we modified an existing mass balance model to predict the indoor air levels of D4 and D5 in both male and female dormitories based on the usage of PCPs. There was a good agreement for D4 and D5 concentrations in female dormitories between modeled and measured concentrations with the ratio of predicted to measured values to be 1.5 and 1.2, respectively, which indicated that use of PCPs was the main source of cVMSs in university dormitories.
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Affiliation(s)
- Qingbo Li
- College of Environmental Science and Engineering, Dalian Maritime University, Dalian, 116026, China.
| | - Xiaoning Lv
- College of Environmental Science and Engineering, Dalian Maritime University, Dalian, 116026, China
| | - Xiaofeng Wang
- College of Environmental Science and Engineering, Dalian Maritime University, Dalian, 116026, China.
| | - Jiaochan Hu
- College of Environmental Science and Engineering, Dalian Maritime University, Dalian, 116026, China
| | - Xianyu Wang
- Queensland Alliance for Environmental Health Sciences, The University of Queensland, 20 Cornwall Street, Woolloongabba, Queensland, 4102, Australia
| | - Jianmin Ma
- Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
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King BM, Janechek NJ, Bryngelson N, Adamcakova-Dodd A, Lersch T, Bunker K, Casuccio G, Thorne PS, Stanier CO, Fiegel J. Lung cell exposure to secondary photochemical aerosols generated from OH oxidation of cyclic siloxanes. CHEMOSPHERE 2020; 241:125126. [PMID: 31683444 PMCID: PMC6941482 DOI: 10.1016/j.chemosphere.2019.125126] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 10/13/2019] [Accepted: 10/14/2019] [Indexed: 06/10/2023]
Abstract
To study the fate of cyclic volatile methyl siloxanes (cVMS) undergoing photooxidation in the environment and to assess the acute toxicity of inhaled secondary aerosols from cVMS, we used an oxidative flow reactor (OFR) to produce aerosols from oxidation of decamethylcyclopentasiloxane (D5). The aerosols produced from this process were characterized for size, shape, and chemical composition. We found that the OFR produced aerosols composed of silicon and oxygen, arranged in chain agglomerates, with primary particles of approximately 31 nm in diameter. Lung cells were exposed to the secondary organosilicon aerosols at estimated doses of 54-116 ng/cm2 using a Vitrocell air-liquid interface system, and organic gases and ozone exposure was minimized through a series of denuders. Siloxane aerosols were not found to be highly toxic.
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Affiliation(s)
- Benjamin M King
- Department of Chemical and Biochemical Engineering, The University of Iowa, 4133 Seamans Center for the Engineering Arts and Sciences, Iowa City, IA, 52242, USA
| | - Nathan J Janechek
- Department of Chemical and Biochemical Engineering, The University of Iowa, 4133 Seamans Center for the Engineering Arts and Sciences, Iowa City, IA, 52242, USA
| | - Nathan Bryngelson
- Department of Chemical and Biochemical Engineering, The University of Iowa, 4133 Seamans Center for the Engineering Arts and Sciences, Iowa City, IA, 52242, USA
| | - Andrea Adamcakova-Dodd
- Department of Occupational and Environmental Health, The University of Iowa, 145 N. Riverside Dr., Iowa City, IA, 52242, USA
| | - Traci Lersch
- RJ Lee Group, 350 Hochberg Road, Monroeville, PA, 15146, USA
| | - Kristin Bunker
- RJ Lee Group, 350 Hochberg Road, Monroeville, PA, 15146, USA
| | - Gary Casuccio
- RJ Lee Group, 350 Hochberg Road, Monroeville, PA, 15146, USA
| | - Peter S Thorne
- Department of Occupational and Environmental Health, The University of Iowa, 145 N. Riverside Dr., Iowa City, IA, 52242, USA
| | - Charles O Stanier
- Department of Chemical and Biochemical Engineering, The University of Iowa, 4133 Seamans Center for the Engineering Arts and Sciences, Iowa City, IA, 52242, USA.
| | - Jennifer Fiegel
- Department of Chemical and Biochemical Engineering, The University of Iowa, 4133 Seamans Center for the Engineering Arts and Sciences, Iowa City, IA, 52242, USA.
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Characterization of an anti-foaming and fast-setting gypsum for dental stone. Dent Mater 2019; 35:1728-1739. [DOI: 10.1016/j.dental.2019.08.110] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 07/18/2019] [Accepted: 08/31/2019] [Indexed: 11/19/2022]
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Lee YS, Lee S, Lim JE, Moon HB. Occurrence and emission of phthalates and non-phthalate plasticizers in sludge from wastewater treatment plants in Korea. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 692:354-360. [PMID: 31351279 DOI: 10.1016/j.scitotenv.2019.07.301] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 07/17/2019] [Accepted: 07/18/2019] [Indexed: 06/10/2023]
Abstract
Phthalates are endocrine-disrupting chemicals that cause adverse health effects in wildlife and humans. Due to domestic and global regulations of phthalates in commercial products, non-phthalate plasticizers (NPPs) have been introduced into industrial markets. Few studies have been conducted on the occurrence of phthalates and NPPs in sludge from wastewater treatment plants (WWTPs). In this study, sludge samples were collected from 40 WWTPs in Korea to investigate the occurrence, compositional profiles, and emission flux of phthalates and NPPs. Total concentrations of phthalates and NPPs in sludge ranged from 4.7 to 1400 (mean: 110) μg/g dry weight and from 0.17 to 780 (mean: 28.0) μg/g dry weight, respectively. Di(2-ethylhexyl)phthalate (DEHP) was a predominant compound, suggesting widespread consumption in Korea. Di(2-ethylhexyl)terephthalate (DEHT) was dominant in industrial sludge samples, whereas di-isononyl cyclohexane-1,2-dicarboxylate (DINCH) and trioctyl trimellitate (TOTM) were dominant in domestic sludge. This implies different consumption patterns of phthalate alternatives by industry and domestic activities. Concentrations of NPPs were significantly correlated with those of high-molecular-weight (HMW) phthalates, indicating that HMW phthalates were preferentially replaced by NPPs. The emission fluxes of phthalates via domestic WWTP activities were higher than those measured for industrial WWTPs, while the emission fluxes of NPPs via industrial WWTPs were higher than those found for domestic and industrial WWTPs. This indicates that phthalate emissions are associated with household activities, while NPP emissions are associated with industrial activities.
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Affiliation(s)
- Young-Sun Lee
- Department of Marine Sciences and Convergence Engineering, Hanyang University, Ansan 15588, Republic of Korea
| | - Sunggyu Lee
- Department of Marine Sciences and Convergence Engineering, Hanyang University, Ansan 15588, Republic of Korea
| | - Jae-Eun Lim
- Department of Marine Sciences and Convergence Engineering, Hanyang University, Ansan 15588, Republic of Korea
| | - Hyo-Bang Moon
- Department of Marine Sciences and Convergence Engineering, Hanyang University, Ansan 15588, Republic of Korea.
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Tran TM, Hoang AQ, Le ST, Minh TB, Kannan K. A review of contamination status, emission sources, and human exposure to volatile methyl siloxanes (VMSs) in indoor environments. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 691:584-594. [PMID: 31325858 DOI: 10.1016/j.scitotenv.2019.07.168] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 07/08/2019] [Accepted: 07/11/2019] [Indexed: 06/10/2023]
Abstract
Siloxanes are organo-silicon compounds containing Si-O-Si linkages and methyl branches. Depending on the structure, siloxanes can be divided into cyclic and linear compounds. Methyl siloxanes with small and medium molecular weights (molecular weights less than 500 g mol-1), are volatile under normal conditions, and hence are referred to as volatile methyl siloxanes (VMSs). VMSs are additive ingredients in many products such as plastics, rubber, personal care products, and household items. This review provides information on the distribution of VMSs in consumer products, indoor air and dust, and their implications for human exposure. VMSs have been used in personal care products and household items at concentrations on the order of hundreds to thousands of micrograms per gram which are the main sources of contamination in the indoor environments. VMSs have been found widely in indoor air and dust. A significant correlation existed between VMS concentrations in indoor air and dust. Among typical VMSs, dodecamethylcylcopentasiloxane (D5) is the major compound found in indoor environments. The human exposure doses to VMSs through dermal absorption, dust ingestion, and inhalation were compiled; Inhalation is a dominant pathway of exposure to VMSs, especially in indoor environments of occupational settings like hair salons. The human exposure doses were higher in children than in adults.
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Affiliation(s)
- Tri Manh Tran
- Faculty of Chemistry, VNU University of Science, Vietnam National University, 19 Le Thanh Tong, Hanoi, Viet Nam.
| | - Anh Quoc Hoang
- Faculty of Chemistry, VNU University of Science, Vietnam National University, 19 Le Thanh Tong, Hanoi, Viet Nam; Center of Advanced Technology for the Environment (CATE), Graduate School of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama 790-8566, Japan; The United Graduate School of Agricultural Sciences (UGAS-EU), Ehime University, 3-5-7 Tarumi, Matsuyama 790-8566, Japan
| | - Son Thanh Le
- Faculty of Chemistry, VNU University of Science, Vietnam National University, 19 Le Thanh Tong, Hanoi, Viet Nam
| | - Tu Binh Minh
- Faculty of Chemistry, VNU University of Science, Vietnam National University, 19 Le Thanh Tong, Hanoi, Viet Nam
| | - Kurunthachalam Kannan
- Wadsworth Center, New York State Department of Health, and Department of Environmental Health Sciences, School of Public Health, State University of New York at Albany, Empire State Plaza, P.O. Box 509, Albany, NY 12201-0509, United States; Biochemistry Department, Faculty of Science and Experimental Biochemistry Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia.
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Horii Y, Nojiri K, Minomo K, Motegi M, Kannan K. Volatile methylsiloxanes in sewage treatment plants in Saitama, Japan: Mass distribution and emissions. CHEMOSPHERE 2019; 233:677-686. [PMID: 31195272 DOI: 10.1016/j.chemosphere.2019.05.247] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 05/23/2019] [Accepted: 05/27/2019] [Indexed: 06/09/2023]
Abstract
Wastewater, aeration gas, dewatered sludge, and incineration ash and flue gas (from dewatered sludge) were collected from 9 sewage treatment plants (STPs) located in Saitama Prefecture, Japan, and analyzed for seven cyclic and linear volatile methylsiloxanes (VMSs) namely, D3, D4, D5, D6, L3, L4, and L5. The mass loadings and distribution of VMSs in STPs were estimated based on measured concentrations in liquid, solid, and gaseous samples, including incinerated dewatered sludge. Mass loading of ΣVMS varied widely from 21 kg y-1 to 3740 kg y-1, depending on the volume of wastewater treated in each STP. Mass % of ΣVMS distributed in aeration gas was 15% and that in activated sludge was 78%. Approximately 6.6% of ΣVMS remained in the final effluent. Overall, partitioning onto the activated sludge was the dominant removal mechanism for D4, D5, and D6, whereas volatilization was also an important removal mechanism for D4. Incineration was effective to degrade VMSs in dewatered sludge, with a reduction rate of >99%. Activated carbon treatment removed >99% of VMSs from the aeration gas. In Saitama Prefecture, total emission of ΣVMS via STPs was estimated at 434 kg y-1, 86 kg y-1, and 0.065 kg y-1, to aquatic, atmospheric, and terrestrial environments, respectively, which accounted for 83%, 17%, and 0.01% of the total environmental emissions. Our results indicate that majority of VMSs in dewatered sludge can be removed by incineration and emission of VMSs through incineration ash landfill is negligible.
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Affiliation(s)
- Yuichi Horii
- Center for Environmental Science in Saitama, 914 Kamitanadare, Kazo, Saitama, 347-0115, Japan.
| | - Kiyoshi Nojiri
- Center for Environmental Science in Saitama, 914 Kamitanadare, Kazo, Saitama, 347-0115, Japan
| | - Kotaro Minomo
- Center for Environmental Science in Saitama, 914 Kamitanadare, Kazo, Saitama, 347-0115, Japan
| | - Mamoru Motegi
- Center for Environmental Science in Saitama, 914 Kamitanadare, Kazo, Saitama, 347-0115, Japan
| | - Kurunthachalam Kannan
- Wadsworth Center, New York State Department of Health, Empire State Plaza, P.O. Box 509, Albany, NY, 12201-0509, USA
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Xu S, Warner N, Bohlin-Nizzetto P, Durham J, McNett D. Long-range transport potential and atmospheric persistence of cyclic volatile methylsiloxanes based on global measurements. CHEMOSPHERE 2019; 228:460-468. [PMID: 31051348 DOI: 10.1016/j.chemosphere.2019.04.130] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 04/11/2019] [Accepted: 04/16/2019] [Indexed: 06/09/2023]
Abstract
This study investigates persistence (P) and long-range transport potential (LRTP) of cyclic volatile methylsiloxanes (cVMS) based on the field measurements in the Northern Hemisphere. The field data consisted of published outdoor air concentrations of octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) and dodecamethylcyclohexasiloxane (D6) at urban, suburban, rural and remote locations excluding the point sources. Three major trends were observed. First, D4 and D6 concentrations were correlated with measured concentrations for D5 at the same times and locations in the majority of the datasets, reflecting the common sources and similar removal mechanism(s) for these compounds. Second, as the sampling sites changed from the source to remote locations along a south-to-north transect, average cVMS concentrations in air decreased in an exponential manner. The empirical characteristic travel distances (eCTD) extracted from these spatial patterns were smaller than model estimated values and differed in order among individual compounds (D4 ∼ D5 < D6). Finally, D5/D6 concentration ratios were also found to decrease exponentially along the same spatial gradient, contrary to model predictions of an increase based on current knowledge of mechanisms controlling atmospheric cVMS degradation. These findings suggest that there may be additional removal process(es) for airborne cVMS, currently not accounted for, that requires further elucidation.
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Affiliation(s)
- Shihe Xu
- Toxicology and Environmental Research and Consulting (TERC), Dow Chemical Company, Midland, MI, 48674, USA.
| | - Nicholas Warner
- NILU-Norwegian Institute for Air Research, Fram Centre, Tromsø, N-9296, Norway
| | | | - Jeremy Durham
- Toxicology and Environmental Research and Consulting (TERC), Dow Chemical Company, Midland, MI, 48674, USA
| | - Debra McNett
- Toxicology and Environmental Research and Consulting (TERC), Dow Chemical Company, Midland, MI, 48674, USA
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Nguyen PM, Afzal M, Ullah I, Shahid N, Baqar M, Arslan M. Removal of pharmaceuticals and personal care products using constructed wetlands: effective plant-bacteria synergism may enhance degradation efficiency. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:21109-21126. [PMID: 31134537 DOI: 10.1007/s11356-019-05320-w] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Accepted: 04/30/2019] [Indexed: 06/09/2023]
Abstract
Post-industrial era has witnessed significant advancements at unprecedented rates in the field of medicine and cosmetics, which has led to affluent use of pharmaceuticals and personal care products (PPCPs). However, this has exacerbated the influx of various pollutants in the environment affecting living organisms through multiple routes. Thousands of PPCPs of various classes-prescription and non-prescription drugs-are discharged directly into the environment. In this review, we have surveyed literature investigating plant-based remediation practices to remove PPCPs from the environment. Our specific aim is to highlight the importance of plant-bacteria interplay for sustainable remediation of PPCPs. The green technologies not only are successfully curbing organic pollutants but also have displayed certain limitations. For example, the presence of biologically active compounds within plant rhizosphere may affect plant growth and hence compromise the phytoremediation potential of constructed wetlands. To overcome these hindrances, combined use of plants and beneficial bacteria has been employed. The microbes (both rhizo- and endophytes) in this type of system not only degrade PPCPs directly but also accelerate plant growth by producing growth-promoting enzymes and hence remediation potential of constructed wetlands.
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Affiliation(s)
- Phuong Minh Nguyen
- Department of Environmental Technology, Faculty of Environmental Sciences, VNU University of Science, Vietnam National University, 334 Nguyen Trai, Thanh Xuan, Hanoi, Vietnam.
| | - Muhammad Afzal
- Soil and Environmental Biotechnology Division, National Institute for Biotechnology and Genetic Engineering, Faisalabad, 38000, Pakistan
| | - Inaam Ullah
- International Join laboratory for Global Climate Change Ecology, School of Life Sciences, Henan University, Kaifeng, Henan, China
| | - Naeem Shahid
- Department System Ecotoxicology, Helmholtz Centre for Environmental Research-UFZ, Permoserstr. 15, Leipzig, 04318, Germany
- Department of Environmental Sciences, COMSATS University Islamabad, Vehari Campus, Islamabad, Pakistan
| | - Mujtaba Baqar
- Sustainable Development Study Centre, Government College University Lahore, Lahore, 54000, Pakistan
| | - Muhammad Arslan
- Soil and Environmental Biotechnology Division, National Institute for Biotechnology and Genetic Engineering, Faisalabad, 38000, Pakistan.
- Department of Environmental Biotechnology, Helmholtz Centre for Environmental Research-UFZ, Permoserstr. 15, 04318, Leipzig, Germany.
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Fromme H, Witte M, Fembacher L, Gruber L, Hagl T, Smolic S, Fiedler D, Sysoltseva M, Schober W. Siloxane in baking moulds, emission to indoor air and migration to food during baking with an electric oven. ENVIRONMENT INTERNATIONAL 2019; 126:145-152. [PMID: 30798195 DOI: 10.1016/j.envint.2019.01.081] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2018] [Revised: 01/30/2019] [Accepted: 01/31/2019] [Indexed: 06/09/2023]
Abstract
Linear and cyclic volatile methylsiloxanes (l-VMS and c-VMS) are man-made chemicals with no natural source. They have been widely used in cosmetics, personal care products, coatings and many other products. As a consequence of their wide use, VMS can be found in different environmental media, as well as in humans. We bought 14 new silicone baking moulds and 3 metallic moulds from the market and used them in different baking experiments. Four of the silicone baking moulds were produced in Germany, two in Italy, four in China, and for the other moulds were no information available. The metal forms were all produced in Germany. VMS were measured in the indoor air throughout the baking process and at the edge and in the center of the finished cakes using a GC/MS system. Additionally, the particle number concentration (PNC) and particle size distribution were measured in the indoor air. The highest median concentrations of VMS were observed immediately following baking: 301 μg/m3 of D7, 212 μg/m3 of D6, and 130 μg/m3 of D8. The silicone moulds containing the highest concentrations of c-VMS corresponded with distinctly higher concentrations of the compounds in indoor air. Using a mould for more than one baking cycle reduced the indoor air concentrations substantially. Samples collected from the edge of the cake had higher concentrations relative to samples from the center, with a mean initial concentration of 6.6 mg/kg of D15, 3.9 mg/kg of D9, 3.7 mg/kg of D12, and 4.8 mg/kg of D18. D3 to D5 were measured only at very low concentrations. Before starting the experiment, an average PNC of 7300 particles/cm3 was observed in the room's air, while a PNC of 140,000 particles/cm3 was observed around the electric stove while it was baking, but this PNC slowly decreased after the oven was switched off. Baking with 4 of the moulds exceeded the German indoor precaution guide value for c-VMS, but the health hazard guide value was not reached during every experiment. Compared to other exposure routes, c-VMS contamination of cake from silicone moulds seems to be low, as demonstrated by the low concentrations of D4 and D6 measured. For less volatile c-VMS > D6 the results of the study indicate that food might play a more important role for daily intake. As a general rule, silicone moulds should be used only after precleaning and while strictly following the temperature suggestions of the producers.
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Affiliation(s)
- Hermann Fromme
- Bavarian Health and Food Safety Authority, Department of Chemical Safety and Toxicology, Pfarrstrasse 3, D-80538 Munich, Germany; Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, Ludwig-Maximilians-University Munich, Ziemssenstrasse 1, D-80336, Munich, Germany.
| | - Matthias Witte
- Bavarian Health and Food Safety Authority, Department of Chemical Safety and Toxicology, Pfarrstrasse 3, D-80538 Munich, Germany
| | - Ludwig Fembacher
- Bavarian Health and Food Safety Authority, Department of Chemical Safety and Toxicology, Pfarrstrasse 3, D-80538 Munich, Germany
| | - Ludwig Gruber
- Fraunhofer Institute Process Engineering and Packaging IVV, Dept. Product Safety and Analysis, Giggenhauser Strasse 35, D-85354 Freising, Germany
| | - Tanja Hagl
- Fraunhofer Institute Process Engineering and Packaging IVV, Dept. Product Safety and Analysis, Giggenhauser Strasse 35, D-85354 Freising, Germany
| | - Sonja Smolic
- Fraunhofer Institute Process Engineering and Packaging IVV, Dept. Product Safety and Analysis, Giggenhauser Strasse 35, D-85354 Freising, Germany
| | - Dominik Fiedler
- Fraunhofer Institute Process Engineering and Packaging IVV, Dept. Product Safety and Analysis, Giggenhauser Strasse 35, D-85354 Freising, Germany
| | - Marina Sysoltseva
- Bavarian Health and Food Safety Authority, Department of Chemical Safety and Toxicology, Pfarrstrasse 3, D-80538 Munich, Germany
| | - Wolfgang Schober
- Bavarian Health and Food Safety Authority, Department of Chemical Safety and Toxicology, Pfarrstrasse 3, D-80538 Munich, Germany
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Guo J, Zhou Y, Zhang B, Zhang J. Distribution and evaluation of the fate of cyclic volatile methyl siloxanes in the largest lake of southwest China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 657:87-95. [PMID: 30530222 DOI: 10.1016/j.scitotenv.2018.11.454] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Revised: 11/26/2018] [Accepted: 11/29/2018] [Indexed: 06/09/2023]
Abstract
Cyclic volatile methyl siloxanes (cVMS) used in personal care products are released to aquatic environments through wastewater effluent. cVMS are persistent, toxic, bioaccumulative, and have potential to cause ecological harm. In this study, the environmental behavior of octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) and dodecamethylcyclohexasiloxane (D6) were evaluated in the largest lake of southwest China, Dian Lake. Air, water and sediment samples were measured for three cVMS compounds in the winter (January) and summer (July) of 2017. In air, D5 exhibited the highest measured mean concentration among the three cVMS, which were 18.4 ± 8.0 ng·m-3 in winter and 5.78 ± 3.61 ng·m-3 in summer. In water and sediment, D6 was the cVMS with the highest measured mean concentration. The mean concentrations in water of D6 were 20.8 ± 5.8 ng·L-1 in winter and 20.4 ± 5.8 ng·L-1 in summer. The mean concentrations in sediment of D6 were 281 ± 45.8 ng·g-1 dw in winter and 270 ± 31.3 ng·g-1 dw in summer. A fugacity-based mass balance chemical fate model for lakes (QWASI) was used for Dian Lake to compare measurements and explore the behavior of cVMS. D6 was predicted to have the highest water column and sediment concentrations. Modeling results showed that most of the D5 and D6 partitioned into sediment and could persist for several years. Persistence was significantly influenced by the high rate of sediment burial. In an analysis of the impact of physicochemical properties and environmental parameters, KOC was identified as a key parameter for predicting cVMS behavior. This study illustrates the importance of cVMS in sediments and the potential aquatic risk that they may pose.
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Affiliation(s)
- Junyu Guo
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Ying Zhou
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Boya Zhang
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Jianbo Zhang
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.
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43
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Janechek NJ, Marek RF, Bryngelson N, Singh A, Bullard RL, Brune WH, Stanier CO. Physical properties of secondary photochemical aerosol from OH oxidation of a cyclic siloxane. ATMOSPHERIC CHEMISTRY AND PHYSICS 2019; 19:1649-1664. [PMID: 31889955 PMCID: PMC6936766 DOI: 10.5194/acp-19-1649-2019] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Cyclic volatile methyl siloxanes (cVMS) are high-production chemicals present in many personal care products. They are volatile, hydrophobic, and relatively long-lived due to slow oxidation kinetics. Evidence from chamber and ambient studies indicates that oxidation products may be found in the condensed aerosol phase. In this work, we use an oxidation flow reactor to produce ~ 100 μgm-3 of organosilicon aerosol from OH oxidation of decamethyl-cyclopentasiloxane (D5) with aerosol mass fractions (i.e., yields) of 0.2-0.5. The aerosols were assessed for concentration, size distribution, morphology, sensitivity to seed aerosol, hygroscopicity, volatility and chemical composition through a combination of aerosol size distribution measurement, tandem differential mobility analysis, and electron microscopy. Similar aerosols were produced when vapor from solid antiperspirant was used as the reaction precursor. Aerosol yield was sensitive to chamber OH and to seed aerosol, suggesting sensitivity of lower-volatility species and recovered yields to oxidation conditions and chamber operation. The D5 oxidation aerosol products were relatively non-hygroscopic, with an average hygroscopicity kappa of ~ 0.01, and nearly non-volatile up to 190 °C temperature. Parameters for exploratory treatment as a semi-volatile organic aerosol in atmospheric models are provided.
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Affiliation(s)
- Nathan J. Janechek
- Department of Chemical and Biochemical Engineering, University of Iowa, Iowa City, IA, USA
- IIHR-Hydroscience and Engineering, University of Iowa, Iowa City, IA, USA
| | - Rachel F. Marek
- IIHR-Hydroscience and Engineering, University of Iowa, Iowa City, IA, USA
| | - Nathan Bryngelson
- Department of Chemical and Biochemical Engineering, University of Iowa, Iowa City, IA, USA
- IIHR-Hydroscience and Engineering, University of Iowa, Iowa City, IA, USA
| | - Ashish Singh
- Department of Chemical and Biochemical Engineering, University of Iowa, Iowa City, IA, USA
- IIHR-Hydroscience and Engineering, University of Iowa, Iowa City, IA, USA
| | - Robert L. Bullard
- Department of Chemical and Biochemical Engineering, University of Iowa, Iowa City, IA, USA
- IIHR-Hydroscience and Engineering, University of Iowa, Iowa City, IA, USA
| | - William H. Brune
- Department of Meteorology and Atmospheric Science, Pennsylvania State University, University Park, PA, USA
| | - Charles O. Stanier
- Department of Chemical and Biochemical Engineering, University of Iowa, Iowa City, IA, USA
- IIHR-Hydroscience and Engineering, University of Iowa, Iowa City, IA, USA
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Yang T, Xiong J, Tang X, Misztal PK. Predicting Indoor Emissions of Cyclic Volatile Methylsiloxanes from the Use of Personal Care Products by University Students. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:14208-14215. [PMID: 29883108 DOI: 10.1021/acs.est.8b00443] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Characterization of indoor emissions of cyclic volatile methylsiloxanes (cVMS) due to the use of personal care products is important for elucidating indoor air composition and associated health risks. This manuscript describes a mass transfer model to characterize the emission behaviors of decamethylcyclopentasiloxane (D5, the most abundant indoor cVMS) from skin lipids. A C-history method is introduced to determine the key parameters in the model, i.e., the initial concentration and diffusion coefficient of D5 inside the skin lipids. Experiments were conducted in a university classroom to examine the D5 emission behaviors by using a proton-transfer-reaction time-of-flight mass spectrometer (PTR-TOF-MS). Data from the first class session of two typical days was applied to obtain the key parameters, which were subsequently used for predicting D5 concentrations in other class sessions. Good agreement between model predictions and experiments demonstrates the effectiveness of the model and parameter determination method. With the model, we found that the reuse of personal care products has a significant impact on the D5 emissions. In addition, the time-dependent emission rate and remaining amount of D5 inside the skin can also be calculated. These results indicate a fast decay pattern during the initial emission period, which is consistent with prior experimental studies.
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Affiliation(s)
- Tao Yang
- School of Mechanical Engineering , Beijing Institute of Technology , Beijing 100081 , China
| | - Jianyin Xiong
- School of Mechanical Engineering , Beijing Institute of Technology , Beijing 100081 , China
- Department of Environmental Science, Policy and Management , University of California , Berkeley , California 94720 , United States
| | - Xiaochen Tang
- Indoor Environment Group, Energy Technologies Area , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Pawel K Misztal
- Department of Environmental Science, Policy and Management , University of California , Berkeley , California 94720 , United States
- Centre for Ecology & Hydrology, Edinburgh , Midlothian EH26 0QB , U.K
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45
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Tran TM, Tu MB, Vu ND. Cyclic siloxanes in indoor environments from hair salons in Hanoi, Vietnam: Emission sources, spatial distribution, and implications for human exposure. CHEMOSPHERE 2018; 212:330-336. [PMID: 30145424 DOI: 10.1016/j.chemosphere.2018.08.101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 08/16/2018] [Accepted: 08/19/2018] [Indexed: 06/08/2023]
Abstract
In this study, three typical cyclic siloxanes (CSis) were found in hair care products, indoor dust and indoor air samples at hair salons in Hanoi, Vietnam. The total concentrations of CSis in three kinds of hair care products ranged from 8.77 to 515 μg g-1. The mean and median concentrations of CSis in dust samples collected at hair salons were 671 and 654 μg g-1, respectively. The total concentrations of CSis in indoor air samples collected at the hair salons ranged from 415 to 2610 ng m-3 (mean: 1030; median: 849 ng m-3, respectively). Among three cyclic siloxanes mentioned in this study, decamethylcyclopentasiloxane (D5) was found at the highest level in all categories of samples. D5 had also a strong correlation between indoor dust and indoor air from hair salons (the coefficient of determination (R2): 0.852); meanwhile dodecamethylcyclohexasiloxane (D6) and octamethylcyclotetrasiloxane (D4) had good correlations (R2 = 0.618 and 0.585, respectively). This result indicates that hair care products are main emission source of cyclic siloxanes in indoor environments at the hair salons. The average exposure doses to total SCis through both of dust ingestion and inhalation were estimated to be 103 and 79.5 ng kg-bw-1 day-1 for women and men, respectively. These levels were higher than those reported for some Asian countries. This is among the most comprehensive investigations on the emission sources and distributions of cyclic siloxanes in indoor dust and indoor air at hair salons in Vietnam.
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Affiliation(s)
- Tri Manh Tran
- Faculty of Chemistry, VNU University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi, Viet Nam.
| | - Minh Binh Tu
- Faculty of Chemistry, VNU University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi, Viet Nam
| | - Nam Duc Vu
- Center for Research and Technology Transfer, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi, Viet Nam
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46
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Kallenborn R, Brorström-Lundén E, Reiersen LO, Wilson S. Pharmaceuticals and personal care products (PPCPs) in Arctic environments: indicator contaminants for assessing local and remote anthropogenic sources in a pristine ecosystem in change. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:33001-33013. [PMID: 28762048 DOI: 10.1007/s11356-017-9726-6] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 07/06/2017] [Indexed: 06/07/2023]
Abstract
A first review on occurrence and distribution of pharmaceuticals and personal care products (PPCPs) is presented. The literature survey conducted here was initiated by the current Assessment of the Arctic Monitoring and Assessment Programme (AMAP). This first review on the occurrence and environmental profile of PPCPs in the Arctic identified the presence of 110 related substances in the Arctic environment based on the reports from scientific publications, national and regional assessments and surveys, as well as academic research studies (i.e., PhD theses). PPCP residues were reported in virtually all environmental compartments from coastal seawater to high trophic level biota. For Arctic environments, domestic and municipal wastes as well as sewage are identified as primary release sources. However, the absence of modern waste water treatment plants (WWTPs), even in larger settlements in the Arctic, is resulting in relatively high release rates for selected PPCPs into the receiving Arctic (mainly) aquatic environment. Pharmaceuticals are designed with specific biochemical functions as a part of an integrated therapeutically procedure. This biochemical effect may cause unwanted environmental toxicological effects on non-target organisms when the compound is released into the environment. In the Arctic environments, pharmaceutical residues are released into low to very low ambient temperatures mainly into aqueous environments. Low biodegradability and, thus, prolonged residence time must be expected for the majority of the pharmaceuticals entering the aquatic system. The environmental toxicological consequence of the continuous PPCP release is, thus, expected to be different in the Arctic compared to the temperate regions of the globe. Exposure risks for Arctic human populations due to consumption of contaminated local fish and invertebrates or through exposure to resistant microbial communities cannot be excluded. However, the scientific results reported and summarized here, published in 23 relevant papers and reports (see Table S1 and following references), must still be considered as indication only. Comprehensive environmental studies on the fate, environmental toxicology, and distribution profiles of pharmaceuticals applied in high volumes and released into the Nordic environment under cold Northern climate conditions should be given high priority by national and international authorities.
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Affiliation(s)
- Roland Kallenborn
- Faculty of Chemistry, Biotechnology and Food Sciences (KBM), Norwegian University of Life Sciences (NMBU), 1432, Ås, Norway.
- Department of Arctic Technology (AT), University Centre in Svalbard (UNIS), 9176, Longyearbyen, Svalbard, Norway.
| | | | - Lars-Otto Reiersen
- Arctic Monitoring and Assessment Programme (AMAP), AMAP Secretariat, 0349, Oslo, Norway
| | - Simon Wilson
- Arctic Monitoring and Assessment Programme (AMAP), AMAP Secretariat, 0349, Oslo, Norway
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47
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Sha B, Dahlberg AK, Wiberg K, Ahrens L. Fluorotelomer alcohols (FTOHs), brominated flame retardants (BFRs), organophosphorus flame retardants (OPFRs) and cyclic volatile methylsiloxanes (cVMSs) in indoor air from occupational and home environments. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 241:319-330. [PMID: 29843014 DOI: 10.1016/j.envpol.2018.04.032] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 04/04/2018] [Accepted: 04/05/2018] [Indexed: 06/08/2023]
Abstract
Indoor air samples were collected from private homes and various occupational indoor environments using passive air sampler and analysed for fluorotelomer alcohols (FTOHs), brominated flame retardants (BFRs), organophosphorus flame retardants (OPFRs) and cyclic volatile methyl siloxanes (cVMSs). The aim was to investigate their occurrence in indoor air, factors that may affect their presence and human daily exposure dose (DED) via inhalation. In general, levels of cVMSs were 3-4 orders of magnitude greater than the other compound classes. OPFRs concentration was found significantly higher than BFRs in indoor air. The most abundant compounds in each chemical class were 8:2 FTOH, 2,4,6-TBP, TNBP and TCEP and decamethylcyclopentasiloxane (D5). Home samples contained higher level of FTOHs, BFRs and cVMSs than occupational environments, whereas concentration of OPFRs in office samples were higher. BFRs concentrations were significantly correlated with building age and with the number of electronic/electrical devices at the sampling sites. Moreover, significantly lower levels of FTOHs and cVMSs were observed in rooms with forced-ventilation system. Estimated DED via inhalation was significantly higher at home than in office and the total DED was on average 3-5 orders of magnitude lower than the reference value.
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Affiliation(s)
- Bo Sha
- Swedish University of Agricultural Sciences (SLU), Department of Aquatic Sciences and Assessment, SE-75007 Uppsala, Sweden
| | - Anna-Karin Dahlberg
- Swedish University of Agricultural Sciences (SLU), Department of Aquatic Sciences and Assessment, SE-75007 Uppsala, Sweden
| | - Karin Wiberg
- Swedish University of Agricultural Sciences (SLU), Department of Aquatic Sciences and Assessment, SE-75007 Uppsala, Sweden
| | - Lutz Ahrens
- Swedish University of Agricultural Sciences (SLU), Department of Aquatic Sciences and Assessment, SE-75007 Uppsala, Sweden.
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Rabhi L, Lemou A, Cecinato A, Balducci C, Cherifi N, Ladji R, Yassaa N. Polycyclic aromatic hydrocarbons, phthalates, parabens and other environmental contaminants in dust and suspended particulates of Algiers, Algeria. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:24253-24265. [PMID: 29948708 DOI: 10.1007/s11356-018-2496-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Accepted: 06/04/2018] [Indexed: 06/08/2023]
Abstract
Chemicals such as polycyclic aromatic hydrocarbons (PAHs), phthalateesters, parabens, siloxanes and squalene, all of them classified as endocrine-disrupting chemicals (EDCs), have been reported to occur in all environmental compartments. The effects of EDCs on development, reproduction, growth, metabolism and obesity constitute a real public health issue. A list of EDCs (> 40 compounds) were characterised in total suspended particulates (outdoor soot: 92 samples) collected in July-September 2016 in an Algiers urban area; besides, settled indoor dusts (36 samples) were collected between November and December 2016 in schools, homes, manufacture and hospital of the same province. The analytical procedure consisted of ultrasonic bath extraction, column chromatography separation into fractions of different polarity and gas chromatographic-mass spectrometric processing. The total loads of phthalates ranging from 6.0 to 347 ng/m2 (median, 26 ng/m2) were determined in indoor dust and 4.6 to 11.6 ng/m3 (median, 7.9 ng/m3) in outdoor soot; meanwhile, PAHs ranged from 12.1 to 108 ng/m2 (median, 36 ng/m2) in indoor dust and ranged from 5.6 to 7.7 ng/m3 (median 5.7 ng/m3) in outdoor soot. Finally, illicit substances such as cocaine, cannabinol and Δ9-tetrahydrocannabinol were found to range from 0.5 to 11 pg/m3, 4.6 to 9.2 pg/m3 and 11 to 81 pg/m3, respectively, in outdoor soot.
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Affiliation(s)
- Lyes Rabhi
- Laboratoire d'Analyse Organique Fonctionnelle, Faculté de Chimie, Université des Sciences et de la Technologie Houari Boumediene, BP 32, El-Alia, Bab Ezzouar, 16111, Algiers, Algeria
- Unité de recherche en analyses et développement technologiques en environnement-centre de recherche scientifique et technique en Analyses physico-chimiques UR-ADTE- CRAPC, BP 384, Zone industrielle RP, 42004, Bou Ismail, Tipaza, Algeria
| | - Abdelkader Lemou
- Laboratoire d'Analyse Organique Fonctionnelle, Faculté de Chimie, Université des Sciences et de la Technologie Houari Boumediene, BP 32, El-Alia, Bab Ezzouar, 16111, Algiers, Algeria
- Unité de recherche en analyses et développement technologiques en environnement-centre de recherche scientifique et technique en Analyses physico-chimiques UR-ADTE- CRAPC, BP 384, Zone industrielle RP, 42004, Bou Ismail, Tipaza, Algeria
| | - Angelo Cecinato
- Institute of Atmospheric Pollution Research (CNR-IIA), National Research Council of Italy, via Salaria, km29.3, P. O. Box10, 00015, Monterotondo, RM, Italy
| | - Catia Balducci
- Institute of Atmospheric Pollution Research (CNR-IIA), National Research Council of Italy, via Salaria, km29.3, P. O. Box10, 00015, Monterotondo, RM, Italy
| | - Nabila Cherifi
- Unité de recherche en analyses et développement technologiques en environnement-centre de recherche scientifique et technique en Analyses physico-chimiques UR-ADTE- CRAPC, BP 384, Zone industrielle RP, 42004, Bou Ismail, Tipaza, Algeria
| | - Riad Ladji
- Unité de recherche en analyses et développement technologiques en environnement-centre de recherche scientifique et technique en Analyses physico-chimiques UR-ADTE- CRAPC, BP 384, Zone industrielle RP, 42004, Bou Ismail, Tipaza, Algeria
| | - Noureddine Yassaa
- Laboratoire d'Analyse Organique Fonctionnelle, Faculté de Chimie, Université des Sciences et de la Technologie Houari Boumediene, BP 32, El-Alia, Bab Ezzouar, 16111, Algiers, Algeria.
- Centre de Développement des Energies Renouvelables, CDER, BP 62, Route de l'Observatoire, Bouzaréah, 16340, Algiers, Algeria.
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49
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Zhi L, Xu L, He X, Zhang C, Cai Y. Occurrence and profiles of methylsiloxanes and their hydrolysis product in aqueous matrices from the Daqing oilfield in China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 631-632:879-886. [PMID: 29727998 DOI: 10.1016/j.scitotenv.2018.03.098] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2018] [Revised: 03/09/2018] [Accepted: 03/09/2018] [Indexed: 06/08/2023]
Abstract
In the present study, the occurrence and distribution of methylsiloxanes (D4-D6, L5-L16) in the surface water and sediment collected from the Daqing oilfield were explored. For wastewater samples from an oilfield combination station, the concentrations of total cyclic methylsiloxanes (∑CMS, D4-D6) and total linear methylsiloxanes (∑LMS, L5-L16) ranged from 137-1911ng/L to 49.4-190ng/L, respectively. Cyclic methylsiloxanes were the predominant methylsiloxanes in the analyzed wastewater samples from the oilfield combination station. In addition, methylsiloxanes were detected in the surface water from three sampling areas, and the total concentrations varied from <LOQ-785ng/L (mean=219±277ng/L, median=120ng/L) for the new oilfield area, 15.1-1808ng/L (mean=270±409ng/L, median=105ng/L) for the old oilfield area and 18.0-252ng/L (mean=103±90.4ng/L, median=52.3ng/L) for the reference area. In the sediment, the ∑CMS and ∑LMS values in the samples collected from the old oilfield area were almost four to nine times higher than those in the samples from the new oilfield area. In addition, elevated concentrations of dimethylsilanediol were detected in the three sampling areas, especially in the old oilfield area (mean=85.6±98.3ng/L), which confirmed that hydrolysis occurred.
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Affiliation(s)
- Liqin Zhi
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Science, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lin Xu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Science, Chinese Academy of Sciences, Beijing 100085, China
| | - Xudan He
- Environmental Protection Research Institute of Light industry, Beijing 100089, China
| | - Chunhui Zhang
- School of Chemical & Environmental Engineering, China University of Mining & Technology (Beijing), Beijing 100083, China
| | - Yaqi Cai
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Science, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China; Institute of Environment and Health, Jianghan University, Wuhan 430056, China.
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50
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Rauert C, Harner T, Schuster JK, Eng A, Fillmann G, Castillo LE, Fentanes O, Villa Ibarra M, Miglioranza KSB, Moreno Rivadeneira I, Pozo K, Aristizábal Zuluaga BH. Atmospheric Concentrations of New Persistent Organic Pollutants and Emerging Chemicals of Concern in the Group of Latin America and Caribbean (GRULAC) Region. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:7240-7249. [PMID: 29846065 DOI: 10.1021/acs.est.8b00995] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A special initiative was run by the Global Atmospheric Passive Sampling (GAPS) Network to provide atmospheric data on a range of emerging chemicals of concern and candidate and new persistent organic pollutants in the Group of Latin America and Caribbean (GRULAC) region. Regional-scale data for a range of flame retardants (FRs) including polybrominated diphenyl ethers (PBDEs), organophosphate esters (OPEs), and a range of alternative FRs (novel FRs) are reported over 2 years of sampling with low detection frequencies of the novel FRs. Atmospheric concentrations of the OPEs were an order of magnitude higher than all other FRs, with similar profiles at all sites. Regional-scale background concentrations of the poly- and perfluoroalkyl substances (PFAS), including the neutral PFAS (n-PFAS) and perfluoroalkyl acids (PFAAs), and the volatile methyl siloxanes (VMS) are also reported. Ethyl perfluorooctane sulfonamide (EtFOSA) was detected at highly elevated concentrations in Brazil and Colombia, in line with the use of the pesticide sulfluramid in this region. Similar concentrations of the perfluoroalkyl sulfonates (PFAS) were detected throughout the GRULAC region regardless of location type, and the VMS concentrations in air increased with the population density of sampling locations. This is the first report of atmospheric concentrations of the PFAAs and VMS from this region.
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Affiliation(s)
- Cassandra Rauert
- Air Quality Processes Research Section , Environment and Climate Change Canada , Toronto , Ontario M3H 5T4 , Canada
| | - Tom Harner
- Air Quality Processes Research Section , Environment and Climate Change Canada , Toronto , Ontario M3H 5T4 , Canada
| | - Jasmin K Schuster
- Air Quality Processes Research Section , Environment and Climate Change Canada , Toronto , Ontario M3H 5T4 , Canada
| | - Anita Eng
- Air Quality Processes Research Section , Environment and Climate Change Canada , Toronto , Ontario M3H 5T4 , Canada
| | - Gilberto Fillmann
- Universidade Federal do Rio Grande , Instituto de Oceanografia , Rio Grande - RS , 96203-900 , Brazil
- Research Centre for Toxic Compounds in the Environment (RECETOX) , Kamenice 753/5, pavillion A29, 625 00 Brno , Czech Republic
| | - Luisa Eugenia Castillo
- Central American Institute for Studies on Toxic Substances (IRET) , Universidad Nacional , Heredia , 86-3000 , Costa Rica
| | | | | | | | | | - Karla Pozo
- Facultad de Ingeniería y Tecnología , Universidad San Sebastián , Lientur 1457 , Concepción , 4080871 , Chile
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