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Kuciński K, Hreczycho G. O-Metalation of silanols and POSS silanols over Amberlyst-15 catalyst: A facile route to unsymmetrical siloxanes, borasiloxanes and germasiloxanes. Inorganica Chim Acta 2019. [DOI: 10.1016/j.ica.2019.03.025] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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102
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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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103
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Kelly A, Franz AK. Metal-Free Synthesis of 1,3-Disiloxanediols and Aryl Siloxanols. ACS OMEGA 2019; 4:6295-6300. [PMID: 31459769 PMCID: PMC6648610 DOI: 10.1021/acsomega.9b00121] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 03/20/2019] [Indexed: 05/28/2023]
Abstract
The first example of metal-free oxidative hydrolysis of hydrido-siloxanes is reported. Both base-catalyzed and organocatalytic hydrolysis methods are demonstrated to transform 1,3-dihydrido-disiloxanes into 1,3-disiloxanediols. The first example of a chemoselective silane hydrolysis is demonstrated.
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104
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Wiesenfeldt MP, Nairoukh Z, Dalton T, Glorius F. Die selektive Arenhydrierung bietet einen direkten Zugang zu gesättigten Carbo‐ und Heterocyclen. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201814471] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Mario P. Wiesenfeldt
- Organisch-Chemisches InstitutWestfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Deutschland
| | - Zackaria Nairoukh
- Organisch-Chemisches InstitutWestfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Deutschland
| | - Toryn Dalton
- Organisch-Chemisches InstitutWestfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Deutschland
| | - Frank Glorius
- Organisch-Chemisches InstitutWestfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Deutschland
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105
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Xue X, Jia H, Xue J. Bioaccumulation of Methyl Siloxanes in Common Carp (Cyprinus carpio) and in an Estuarine Food Web in Northeastern China. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2019; 76:496-507. [PMID: 30259079 DOI: 10.1007/s00244-018-0569-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2018] [Accepted: 09/17/2018] [Indexed: 06/08/2023]
Abstract
Despite the high production volume and widespread use of methyl siloxanes, limited studies have been conducted to investigate the bioconcentration, biomagnification, and trophic magnification potentials of these substances. In the present study, bioconcentration factors (BCFs) of methyl siloxanes were determined with common carp exposed at environmental relevant levels for 32 days. BCF of octamethylcyclotetrasiloxane (D4) was estimated as 6197 L/Kg, indicating strong bioconcentration potential in the common carp. To assess the food chain transfer of methyl siloxanes, 12 aquatic invertebrates and vertebrates species were collected from a food web in Shuangtaizi estuary in northeastern China and concentrations of methyl siloxanes in these species were determined with gas chromatography mass spectrometry. Trophic magnification factors (TMFs) of decamethylcyclopentasiloxane (D5), dodecamethylcyclohexasiloxane (D6), and linear siloxanes (L7-10) were significantly greater than 1 in one food chain selected, which suggest trophic magnification potentials of these methyl siloxanes. Biomagnification factors of D4-D6 and L7-L10 from planktons to Japanese snapping shrimp were greater than 1, indicating biomagnification potentials of these methyl siloxanes from the prey to predator. This is the first study to investigate the bioaccumulation behaviors of methyl siloxanes by coupling BCF and BMF with TMF.
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Affiliation(s)
- Xiaohong Xue
- College of Science, Dalian Maritime University, 1 Linghai Road, Dalian, 116026, Liaoning, China
| | - Hongliang Jia
- International Joint Research Centre for Persistent Toxic Substances (IJRC-PTS), College of Environmental Science and Engineering, Dalian Maritime University, Dalian, 116026, China
| | - Jingchuan Xue
- Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA.
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106
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Kümmerer K, Dionysiou DD, Olsson O, Fatta-Kassinos D. Reducing aquatic micropollutants - Increasing the focus on input prevention and integrated emission management. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 652:836-850. [PMID: 30380490 DOI: 10.1016/j.scitotenv.2018.10.219] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 10/15/2018] [Accepted: 10/15/2018] [Indexed: 06/08/2023]
Abstract
Pharmaceuticals and many other chemicals are an important basis for nearly all sectors including for example, food and agriculture, medicine, plastics, electronics, transport, communication, and many other products used nowadays. This comes along with a tremendous chemicalization of the globe, including ubiquitous presence of products of chemical and pharmaceutical industries in the aquatic environment. Use of these products will increase with population growth and living standard as will the need for clean water. In addition, climate change will exacerbate availability of water in sufficient quantity and quality. Since its implementation, conventional wastewater treatment has increasingly contributed to environmental protection and health of humans. However, with the increasing pollution of water by chemicals, conventional treatment turned out to be insufficient. It was also found that advanced effluent treatment methods such as extended filtration, the sorption to activated charcoal or advanced oxidation methods have their own limitations. These are, for example, increased demand for energy and hazardous chemicals, incomplete or even no removal of pollutants, the generation of unwanted products from parent compounds (transformation products, TPs) of often-unknown chemical structure, fate and toxicity. In many countries, effluent treatment is available only rarely if at all let alone advanced treatment. The past should teach us, that focusing only on technological approaches is not constructive for a sustainable water quality control. Therefore, in addition to conventional and advanced treatment optimization more emphasis on input prevention is urgently needed, including more and better control of what is present in the source water. Measures for input prevention are known for long. The main focus though has always been on the treatment, and measures taken at the source have gained only little attention so far. A more effective and efficient approach, however, would be to avoid pollution at the source, which would in turn allow more targeted treatment to meet treated water quality objectives globally. New developments within green and sustainable chemistry are offering new approaches that allow for input prevention and a more targeted treatment to succeed in pollution elimination in and at the source. To put this into practice, engineers, water scientists and chemists as well as microbiologists and scientists of other related disciplines need to cooperate more extensively than in the past. Applying principles such as the precautionary principle, or keeping water flows separate where possible will add to this. This implies not minimizing the efforts to improve wastewater treatment but to design effluents and chemicals in such a way that treatment systems and water environments can cope successfully with the challenge of micropollutants globally (Kümmerer et al., 2018). This paper therefore presents in its first part some of the limitations of effluent treatment in order to demonstrate the urgent need for minimizing water pollution at the source and, information on why source management is urgently needed to improve water quality and stimulate discussions how to protect water resources on a global level. Some principles of green and sustainable chemistry as well as other approaches, which are part of source management, are presented in the second part in order to stimulate discussion.
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Affiliation(s)
- Klaus Kümmerer
- Institute of Sustainable and Environmental Chemistry, Leuphana University Lüneburg, Universitätsallee 1, 21335 Lüneburg, Germany; International Sustainable Chemistry Collaboration Center (ISC(3)), Research and Education, Leuphana University Lüneburg, Universitätsallee 1, 21335 Lüneburg, Germany.
| | - Dionysios D Dionysiou
- Environmental Engineering and Science Program, Department of Chemical and Environmental Engineering (DCEE), 705 Engineering Research Center, University of Cincinnati, Cincinnati, OH 45221-0012, USA; Nireas-International Water Research Center, University of Cyprus, P.O. Box 20537, 1678, Nicosia, Cyprus
| | - Oliver Olsson
- Institute of Sustainable and Environmental Chemistry, Leuphana University Lüneburg, Universitätsallee 1, 21335 Lüneburg, Germany
| | - Despo Fatta-Kassinos
- Nireas-International Water Research Center, University of Cyprus, P.O. Box 20537, 1678, Nicosia, Cyprus; Department of Civil and Environmental Engineering, University of Cyprus, P.O. Box 20537, 1678, Nicosia, Cyprus
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107
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Rocha F, Homem V, Castro-Jiménez J, Ratola N. Marine vegetation analysis for the determination of volatile methylsiloxanes in coastal areas. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 650:2364-2373. [PMID: 30292992 DOI: 10.1016/j.scitotenv.2018.10.012] [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: 05/08/2018] [Revised: 09/08/2018] [Accepted: 10/01/2018] [Indexed: 06/08/2023]
Abstract
Volatile methylsiloxanes (VMSs) are massively produced chemicals that comprise a wide range of industrial and household applications. The presence of cyclic and linear VMSs in several environmental matrices and ecosystems indicates persistence associated with a potential of (bio)accumulation and food web transfer with possible toxicological effects. Due to the high anthropogenic pressure in its vicinities particularly in summer, coastal areas in Southern European countries are potential hotspots for the presence of VMSs. The massive afflux of tourists and consequent increase of the use of personal care products (PCPs) with VMSs in their formulations highlight the importance of VMSs assessment in such areas. In this study, different species of marine vegetation (algae and seaweed) were collected in three different geographical areas, covering the Atlantic Ocean (North coast of Portugal), as well as the Mediterranean Sea (coasts of the Region of Murcia, Spain and of the city of Marseille, France). Samples were analysed for the determination of 4 cyclic (D3, D4, D5, D6) and 3 linear (L3, L4, L5) VMSs employing a QuEChERS extraction methodology, followed by gas chromatography/mass spectrometry (GC/MS) quantification. VMSs were detected in 92% of the 74 samples analysed, with the sum of the concentrations per sample ranging from below the limit of detection (LOD) to 458 ± 26 ng·g-1dw (dry weight). A strong predominance of cyclic VMSs over linear ones was verified in almost all samples studied, with D5 and D6 found at higher concentrations. Seasonal variation was also assessed and despite higher levels of VMSs being identified mostly in summer months, clear seasonal trends were not perceived. It was also noted that generally the higher incidence of VMSs occurred in samples from urban and industrialized areas or in the vicinities of WWTPs, suggesting a direct input from these sources in the levels of siloxanes observed.
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Affiliation(s)
- Filipe Rocha
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Vera Homem
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Javier Castro-Jiménez
- Aix Marseille Univ., University of Toulon, CNRS, IRD, Mediterranean Institute of Oceanography (MIO), UM 110, Marseille, France
| | - Nuno Ratola
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.
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108
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Zhi L, Xu L, He X, Zhang C, Cai Y. Distribution of methylsiloxanes in benthic mollusks from the Chinese Bohai Sea. J Environ Sci (China) 2019; 76:199-207. [PMID: 30528010 DOI: 10.1016/j.jes.2018.04.026] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 04/25/2018] [Accepted: 04/25/2018] [Indexed: 06/09/2023]
Abstract
Methylsiloxanes are a class of silicone compounds that have been widely used in various industrial processes and personal care products for several decades. This study investigated the spatial distribution of three cyclic methylsiloxanes (D4-D6) and twelve linear methylsiloxanes (L5-L16) in mollusks collected from seven cities along the Bohai Sea. D4-D6 (df = 71%-81%) and L8-L16 (df = 32%-40%) were frequently detectable in the mollusk samples, while L5-L7 were not found in any mollusk samples. Cyclic methylsiloxanes (D4-D6) were found in mollusks with the mean concentrations of 15.7 ± 12.3 ng/g ww for D4, 24.6 ± 15.8 ng/g ww for D5 and 34.0 ± 23.0 ng/g ww for D6. Among the seven sampling cities, the cyclic methylsiloxanes were predominant in mollusks, with the total cyclic methylsiloxanes (sum of D4-D6, ∑CMS) accounting for 74.2%-80.7% of the total methylsiloxanes. ∑CMS along the coastline demonstrated a clear gradient, with the highest concentrations in mollusks at the sampling sites located in the western part of the Bohai Sea and the lowest concentrations in mollusks from cities located in the eastern part of the Bohai Sea. The biota-sediment accumulation factors for cyclic methylsiloxanes (D4-D6) and linear methylsiloxanes (L8-L16) were estimated as 0.42 ± 0.06-0.53 ± 0.06 and 0.13 ± 0.03-0.19 ± 0.05, respectively.
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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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109
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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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110
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Zhi L, Xu L, Qu Y, Zhang C, Cao D, Cai Y. Identification and Elimination of Fluorinated Methylsiloxanes in Environmental Matrices near a Manufacturing Plant in Eastern China. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:12235-12243. [PMID: 30339022 DOI: 10.1021/acs.est.8b02508] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Fluorinated methylsiloxanes are modified methylsiloxanes and include tris(trifluoropropyl)trimethylcyclotrisiloxane (D3F) and tetrakis(trifluoropropyl)tetramethylcyclotetrasiloxane (D4F). Here, we report fluorinated methylsiloxanes (D3F and D4F) in surface water and sediment samples collected near a fluorinated methylsiloxane manufacturing plant in Weihai, China. The concentrations of D3F and D4F in surface water ranged from 3.29-291 ng/L and from 7.02-168 ng/L, respectively. The concentrations of D3F and D4F in sediment ranged from 11.8-5478 ng/g and from 17.2-6277 ng/g, respectively. In simulation experiment, the half-lives of D3F and D4F at different pH values (5.2, 6.4, 7.2, 8.3, and 9.2) varied from 80.6-154 h and from 267-533 h, respectively. CF3(CH2)2MeSi(OH)2 was identified as one of the main hydrolysis products of fluorinated methylsiloxanes. It was also detected in the river samples at concentrations of 72.1-182.9 ng/L. In addition, the slow rearrangement of D3F (spiked concentration = 500 ng/L) to D4F (concentration = 11.0-22.7 ng/L) was also found during 336h hydrolysis experiment.
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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
- Environmental Protection Research Institute of Light industry, Beijing 100089 , China
| | - Lin Xu
- 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
| | - Yao Qu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Science , Chinese Academy of Sciences , Beijing 100085 , China
- School of Chemical & Environmental Engineering , China University of Mining & Technology (Beijing) , Beijing 100083 , China
| | - Chunhui Zhang
- School of Chemical & Environmental Engineering , China University of Mining & Technology (Beijing) , Beijing 100083 , China
| | - Dong Cao
- 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
- Institute of Environment and Health , Jianghan University , Wuhan 430056 , China
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111
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Sturm AG, Schweizer JI, Meyer L, Santowski T, Auner N, Holthausen MC. Lewis Base Catalyzed Selective Chlorination of Monosilanes. Chemistry 2018; 24:17796-17801. [DOI: 10.1002/chem.201803921] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Indexed: 11/10/2022]
Affiliation(s)
- Alexander G. Sturm
- Institut für Anorganische und Analytische Chemie; Goethe-Universität; Max-von-Laue-Straße 7 60438 Frankfurt/Main Germany
| | - Julia I. Schweizer
- Institut für Anorganische und Analytische Chemie; Goethe-Universität; Max-von-Laue-Straße 7 60438 Frankfurt/Main Germany
| | - Lioba Meyer
- Institut für Anorganische und Analytische Chemie; Goethe-Universität; Max-von-Laue-Straße 7 60438 Frankfurt/Main Germany
| | - Tobias Santowski
- Institut für Anorganische und Analytische Chemie; Goethe-Universität; Max-von-Laue-Straße 7 60438 Frankfurt/Main Germany
| | - Norbert Auner
- Institut für Anorganische und Analytische Chemie; Goethe-Universität; Max-von-Laue-Straße 7 60438 Frankfurt/Main Germany
| | - Max C. Holthausen
- Institut für Anorganische und Analytische Chemie; Goethe-Universität; Max-von-Laue-Straße 7 60438 Frankfurt/Main Germany
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112
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Feng J, Zhang F, Zhao J, Guo W, Sun J. An improved quantification method for 12 linear dimethylsiloxanes and 1 cyclic dimethylsiloxane in polydimethylsiloxane using gas chromatography-flame ionization detector:Development strategy and accuracy. J Chromatogr A 2018; 1578:112-116. [PMID: 30309705 DOI: 10.1016/j.chroma.2018.10.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 08/30/2018] [Accepted: 10/01/2018] [Indexed: 01/17/2023]
Abstract
PDMS 200 fluid (the mixture) was used as standard for quantification of linear dimethylsiloxanes (L5-L16) in environmental matrices. However, the quantification of individual dimethylsiloxane in PDMS 200 fluid by GC-FID was not established or detailed described in many real studies. To solve this problem, we did this research and the principal results were as follows: fifteen compounds in PDMS 200 fluid, including D7, L5 to L16 (12 linear dimethylsiloxanes) and 2 unknown compounds, were identified using GC-MS. Retention indices (RI) of L8 to L16 were first given. Meanwhile, we found that the "effective carbon number (ECN) concept" was applicable for responses of dimethylsiloxanes in FID. Based on GC-FID, a new quantification method for compounds in PDMS 200 fluid was established, detailed described and used to calculate the content of individual dimethylsiloxane in PDMS 200 fluid. Compared with the results from external standard method, internal standard method and normalization method, the new quantification method was more accurate and stable, especially for D7 at low content.
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Affiliation(s)
- Jinglan Feng
- School of Environment, Henan Normal University, Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, Xinxiang, Henan 453007, PR China.
| | - Fei Zhang
- School of Environment, Henan Normal University, Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, Xinxiang, Henan 453007, PR China
| | - Jiahui Zhao
- School of Environment, Henan Normal University, Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, Xinxiang, Henan 453007, PR China
| | - Wei Guo
- Department of Chemistry, Xinxiang Medical University, Henan 453003, PR China
| | - Jianhui Sun
- School of Environment, Henan Normal University, Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, Xinxiang, Henan 453007, PR China.
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113
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Vijjamarri S, Hull M, Kolodka E, Du G. Renewable Isohexide-Based, Hydrolytically Degradable Poly(silyl ether)s with High Thermal Stability. CHEMSUSCHEM 2018; 11:2881-2888. [PMID: 29958332 DOI: 10.1002/cssc.201801123] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 06/25/2018] [Indexed: 06/08/2023]
Abstract
Several degradable poly(silyl ether)s (PSEs) have been synthesized by dehydrogenative cross-coupling between bio-based 1,4:3,6-dianhydrohexitols (isosorbide and isomannide) and commercially available hydrosilanes. An air-stable manganese salen nitrido complex [MnV N(salen-3,5-tBu2 )] was employed as the catalyst. High-molecular-weight polymer was obtained from isosorbide and diphenylsilane (Mn up to 17000 g mol-1 ). Thermal analysis showed that these PSEs possessed high thermal stability with thermal decomposition temperatures (T-5 % ) of 347-446 °C and glass transition temperatures of 42-120 °C. Structure-property analysis suggested that steric bulk and molecular weight have a significant influence to determine the thermal properties of synthesized polymers. Importantly, these polymers were degraded effectively to small molecules under acidic and basic hydrolysis conditions.
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Affiliation(s)
- Srikanth Vijjamarri
- Department of Chemistry, University of North Dakota, 151 Cornell Street Stop 9024, Grand Forks, North Dakota, 58202, USA
| | - Marianne Hull
- Department of Chemistry, University of North Dakota, 151 Cornell Street Stop 9024, Grand Forks, North Dakota, 58202, USA
| | - Edward Kolodka
- Department of Chemical Engineering, University of North Dakota, 241 Centennial Dr. Stop 7101, Grand Forks, North Dakota, 58202, USA
| | - Guodong Du
- Department of Chemistry, University of North Dakota, 151 Cornell Street Stop 9024, Grand Forks, North Dakota, 58202, USA
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114
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Xu L, Xu S, Zhang Q, Xu Q, Zhang S, Cai Y. Sources and Fate of Cyclic Phenylmethylsiloxanes in One Municipal Wastewater Treatment Plant and Biosolids-Amended Soil. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:9835-9844. [PMID: 30099875 DOI: 10.1021/acs.est.8b03096] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
cis-/ trans-2,4,6-Triphenyl-2,4,6-trimethylcyclotrisiloxanes ( cis-P3 and trans-P3) and cis-/ trans-2,4,6,8-tetraphenyl-2,4,6,8-tetramethylcyclotetrasiloxanes ( cis-P4 and trans-P4a,b,c) were detected in personal care products [<LOD-54.2 μg/g, detection frequencies (df) = 14.5-15.5%, n = 110] collected from a Chinese city, suggesting their potential release to local municipal wastewater treatment plant (WWTP). In the local WWTP, per capita mass loadings of P3 and P4 were 43.4-340 μg/d in influents, while neither P3 nor P4 was detected in effluents. Due to large solid/water distribution coefficients (apparent Log Kd = 3.42-3.99), sorption to sludge had a dominant contribution (95.6-99.2%) to phenylmethylsiloxanes removal in the WWTP. As amended by biosolids containing phenylmethylsiloxanes [66.2 ng/g to 2.63 μg/g dw (dry weight)] from this WWTP, concentrations (<LOD -255 ng/g dw, df = 27.5-52.5%, n = 120) of six phenylmethylsiloxane isomers in soils from one commercial forest were significantly higher than those (<LOD) in the reference area without biosolids application, but no increasing trend was found at six sampling events during July 2015 to February 2017. Simulated experiments indicated that hydrolysis half-lives of phenylmethylsiloxanes (1.50-6.50 d for P3, 16.5-65.4 d for P4) in soil were 4.74-46.3 times shorter than volatilization half-lives (51.9-120 d for P3, 158-376 d for P4). For both cyclic phenylmethylsiloxanes, their trans-isomers had lower (1.14-1.82 times) degradation rates than their cis-isomers.
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Affiliation(s)
- Lin Xu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences , Chinese Academy of Sciences , Beijing 100085 , China
| | - Shihe Xu
- Toxicology & Environmental Research and Consulting (TERC) , The Dow Chemical Company , Midland , Michigan 48674 , United States
| | - Qiaoli Zhang
- School of Chemistry & Material Science , Ludong University , Yantai 264025 , China
| | - Qiang Xu
- School of Chemistry & Material Science , Ludong University , Yantai 264025 , China
| | - Shengxiao Zhang
- School of Chemistry & Material Science , Ludong University , Yantai 264025 , 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
- Institute of Environment and Health , Jianghan University , Wuhan 430056 , China
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115
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Fondeur F, Crump S, White T. Analysis of antifoam agent degradation products in an evaporator. SEP SCI TECHNOL 2018. [DOI: 10.1080/01496395.2018.1462831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Affiliation(s)
- Fernando Fondeur
- Savannah River National Lab, Analytical Development Section, Aiken, South Carolina, USA
| | - Stephen Crump
- Savannah River National Lab, Analytical Development Section, Aiken, South Carolina, USA
| | - Thomas White
- Savannah River National Lab, Analytical Development Section, Aiken, South Carolina, USA
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116
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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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117
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Fernández‐Alvarez FJ, Oro LA. Homogeneous Catalytic Reduction of CO
2
with Silicon‐Hydrides, State of the Art. ChemCatChem 2018. [DOI: 10.1002/cctc.201800699] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Francisco J. Fernández‐Alvarez
- Departamento de Química Inorgánica Instituto de Síntesis Química y Catálisis Homogénea (ISQCH)Universidad de Zaragoza Facultad de Ciencias 50009 Zaragoza Spain
| | - Luis A. Oro
- Departamento de Química Inorgánica Instituto de Síntesis Química y Catálisis Homogénea (ISQCH)Universidad de Zaragoza Facultad de Ciencias 50009 Zaragoza Spain
- Center of Refining & PetrochemicalsKing Fahd University of Petroleum & Minerals 31261 Dhahran Saudi Arabia
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118
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Wiesenfeldt MP, Knecht T, Schlepphorst C, Glorius F. Silylarenhydrierung – ein strategischer Ansatz für einen direkten Zugang zu silylierten gesättigten Carbo‐ und Heterocyclen. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201804124] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Mario P. Wiesenfeldt
- Organisch-Chemisches InstitutWestfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Deutschland
| | - Tobias Knecht
- Organisch-Chemisches InstitutWestfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Deutschland
| | - Christoph Schlepphorst
- Organisch-Chemisches InstitutWestfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Deutschland
| | - Frank Glorius
- Organisch-Chemisches InstitutWestfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Deutschland
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119
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Wiesenfeldt MP, Knecht T, Schlepphorst C, Glorius F. Silylarene Hydrogenation: A Strategic Approach that Enables Direct Access to Versatile Silylated Saturated Carbo‐ and Heterocycles. Angew Chem Int Ed Engl 2018; 57:8297-8300. [DOI: 10.1002/anie.201804124] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2018] [Indexed: 12/11/2022]
Affiliation(s)
- Mario P. Wiesenfeldt
- Organisch-Chemisches InstitutWestfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
| | - Tobias Knecht
- Organisch-Chemisches InstitutWestfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
| | - Christoph Schlepphorst
- Organisch-Chemisches InstitutWestfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
| | - Frank Glorius
- Organisch-Chemisches InstitutWestfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
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120
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Coggon MM, McDonald BC, Vlasenko A, Veres PR, Bernard F, Koss AR, Yuan B, Gilman JB, Peischl J, Aikin KC, DuRant J, Warneke C, Li SM, de Gouw JA. Diurnal Variability and Emission Pattern of Decamethylcyclopentasiloxane (D 5) from the Application of Personal Care Products in Two North American Cities. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:5610-5618. [PMID: 29659257 DOI: 10.1021/acs.est.8b00506] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Decamethylcyclopentasiloxane (D5) is a cyclic volatile methyl siloxane (cVMS) that is widely used in consumer products and commonly observed in urban air. This study quantifies the ambient mixing ratios of D5 from ground sites in two North American cities (Boulder, CO, USA, and Toronto, ON, CA). From these data, we estimate the diurnal emission profile of D5 in Boulder, CO. Ambient mixing ratios were consistent with those measured at other urban locations; however, the diurnal pattern exhibited similarities with those of traffic-related compounds such as benzene. Mobile measurements and vehicle experiments demonstrate that emissions of D5 from personal care products are coincident in time and place with emissions of benzene from motor vehicles. During peak commuter times, the D5/benzene ratio (w/w) is in excess of 0.3, suggesting that the mass emission rate of D5 from personal care product usage is comparable to that of benzene due to traffic. The diurnal emission pattern of D5 is estimated using the measured D5/benzene ratio and inventory estimates of benzene emission rates in Boulder. The hourly D5 emission rate is observed to peak between 6:00 and 7:00 AM and subsequently follow an exponential decay with a time constant of 9.2 h. This profile could be used by models to constrain temporal emission patterns of personal care products.
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Affiliation(s)
- Matthew M Coggon
- NOAA Earth Systems Research Laboratory , Boulder , Colorado 80305 , United States
- Cooperative Institute for Research in Environmental Sciences , Boulder , Colorado 80309 , United States
| | - Brian C McDonald
- NOAA Earth Systems Research Laboratory , Boulder , Colorado 80305 , United States
- Cooperative Institute for Research in Environmental Sciences , Boulder , Colorado 80309 , United States
| | - Alexander Vlasenko
- Air Quality Processes Research Section , Environment and Climate Change Canada , Toronto , Ontario M3H 5T4 , Canada
| | - Patrick R Veres
- NOAA Earth Systems Research Laboratory , Boulder , Colorado 80305 , United States
- Cooperative Institute for Research in Environmental Sciences , Boulder , Colorado 80309 , United States
| | - François Bernard
- NOAA Earth Systems Research Laboratory , Boulder , Colorado 80305 , United States
- Cooperative Institute for Research in Environmental Sciences , Boulder , Colorado 80309 , United States
| | - Abigail R Koss
- NOAA Earth Systems Research Laboratory , Boulder , Colorado 80305 , United States
- Cooperative Institute for Research in Environmental Sciences , Boulder , Colorado 80309 , United States
| | - Bin Yuan
- NOAA Earth Systems Research Laboratory , Boulder , Colorado 80305 , United States
- Cooperative Institute for Research in Environmental Sciences , Boulder , Colorado 80309 , United States
| | - Jessica B Gilman
- NOAA Earth Systems Research Laboratory , Boulder , Colorado 80305 , United States
| | - Jeff Peischl
- NOAA Earth Systems Research Laboratory , Boulder , Colorado 80305 , United States
- Cooperative Institute for Research in Environmental Sciences , Boulder , Colorado 80309 , United States
| | - Kenneth C Aikin
- NOAA Earth Systems Research Laboratory , Boulder , Colorado 80305 , United States
- Cooperative Institute for Research in Environmental Sciences , Boulder , Colorado 80309 , United States
| | - Justin DuRant
- Department of Biology , University of South Carolina , Columbia , South Carolina 29208 , United States
| | - Carsten Warneke
- NOAA Earth Systems Research Laboratory , Boulder , Colorado 80305 , United States
- Cooperative Institute for Research in Environmental Sciences , Boulder , Colorado 80309 , United States
| | - Shao-Meng Li
- Air Quality Processes Research Section , Environment and Climate Change Canada , Toronto , Ontario M3H 5T4 , Canada
| | - Joost A de Gouw
- Cooperative Institute for Research in Environmental Sciences , Boulder , Colorado 80309 , United States
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121
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Taha YM, Saowapon MT, Osthoff HD. Detection of triacetone triperoxide by thermal decomposition peroxy radical chemical amplification coupled to cavity ring-down spectroscopy. Anal Bioanal Chem 2018; 410:4203-4212. [DOI: 10.1007/s00216-018-1072-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 03/14/2018] [Accepted: 04/09/2018] [Indexed: 11/25/2022]
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122
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Exploring the potential of infrared spectroscopy on the study of the adsorption/desorption of siloxanes for biogas purification. Catal Today 2018. [DOI: 10.1016/j.cattod.2017.01.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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123
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Villanueva F, Tapia A, Lara S, Amo-Salas M. Indoor and outdoor air concentrations of volatile organic compounds and NO 2 in schools of urban, industrial and rural areas in Central-Southern Spain. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 622-623:222-235. [PMID: 29212055 DOI: 10.1016/j.scitotenv.2017.11.274] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 11/21/2017] [Accepted: 11/24/2017] [Indexed: 05/06/2023]
Abstract
Thirty two VOCs including alkanes, aromatic hydrocarbons, terpenes and carbonyl compounds together with NO2 were investigated in a kindergarten classroom, a primary classroom and the playground in 18 schools located in rural areas, an urban area (Ciudad Real) and an industrial area (Puertollano) in the province of Ciudad Real in central southern Spain. The most abundant pollutants at schools were the aldehydes formaldehyde and hexanal. After carbonyls, n-dodecane was the most abundant compound in the study areas. The NO2 concentrations were higher in the urban area, followed by industrial area and rural areas. For benzene, its concentration in the industrial area was significantly higher than in the urban and rural areas which reflects the magnitude of the contribution to the indoor air by petrochemical plant during the sampling period. Principal component analysis, indoor/outdoor ratios, multiple linear regressions and Spearman correlation coefficients were used to investigate the origin, the indoor pollutant determinants and to establish common sources between VOCs and NO2. Seven components were extracted from the application of PCA to the indoor measurements accounting for 77.5% of the total variance. The analysis of indoor/outdoor ratios and correlations demonstrated that sources in the indoor environment are prevailing for most of the investigated VOCs. Benzene and n-pentane have a major relevance as outdoor sources, while aldehydes, terpenes, alkanes and most aromatic hydrocarbons as indoor sources. For NO2, ethylbenzene and toluene both indoor and outdoor sources probably contributed to the measured concentrations. Finally, the results reported in this paper demonstrate that during the measuring period there were not great differences in the indoor air quality of the schools of the three study areas.
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Affiliation(s)
- Florentina Villanueva
- Atmospheric Pollution Laboratory, Research Institute for Combustion and Atmospheric Pollution, University of Castilla-La Mancha, Camino de Moledores s/n, 13071 Ciudad Real, Spain; Castilla-La Mancha Science and Technology Park, Paseo de la Innovación 1, 02006 Albacete, Spain.
| | - Araceli Tapia
- Physical Chemistry Department, Faculty of Chemical Sciences and Technologies, University of Castilla-La Mancha, Avenida Camilo José Cela s/n, Spain.
| | - Sonia Lara
- Atmospheric Pollution Laboratory, Research Institute for Combustion and Atmospheric Pollution, University of Castilla-La Mancha, Camino de Moledores s/n, 13071 Ciudad Real, Spain.
| | - Mariano Amo-Salas
- Department of Mathematics, Faculty of Medicine, University of Castilla La Mancha, Camino de Moledores s/n, 13071 Ciudad Real, Spain.
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124
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Bernard F, Papanastasiou DK, Papadimitriou VC, Burkholder JB. Temperature Dependent Rate Coefficients for the Gas-Phase Reaction of the OH Radical with Linear (L2, L3) and Cyclic (D3, D4) Permethylsiloxanes. J Phys Chem A 2018; 122:4252-4264. [DOI: 10.1021/acs.jpca.8b01908] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- François Bernard
- Earth System Research Laboratory, Chemical Sciences Division, National Oceanic and Atmospheric Administration, Boulder, Colorado 80305, United States
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80309, United States
| | - Dimitrios K. Papanastasiou
- Earth System Research Laboratory, Chemical Sciences Division, National Oceanic and Atmospheric Administration, Boulder, Colorado 80305, United States
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80309, United States
| | - Vassileios C. Papadimitriou
- Earth System Research Laboratory, Chemical Sciences Division, National Oceanic and Atmospheric Administration, Boulder, Colorado 80305, United States
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80309, United States
| | - James B. Burkholder
- Earth System Research Laboratory, Chemical Sciences Division, National Oceanic and Atmospheric Administration, Boulder, Colorado 80305, United States
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125
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Kim J, Mackay D, Whelan MJ. Predicted persistence and response times of linear and cyclic volatile methylsiloxanes in global and local environments. CHEMOSPHERE 2018; 195:325-335. [PMID: 29272801 DOI: 10.1016/j.chemosphere.2017.12.071] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 12/08/2017] [Accepted: 12/11/2017] [Indexed: 06/07/2023]
Abstract
We investigated the response times of eight volatile methylsiloxanes (VMSs) in environmental systems at different scales from local to global, with a particular focus on overall loss rates after cessation of emissions. In part, this is driven by proposals to restrict the use of some of these compounds in certain products in Europe. The GloboPOP model estimated low absolute Arctic Contamination Potentials for all VMSs and rapid response times in all media except sediment. VMSs are predicted to be distributed predominantly in air where they react with OH radicals, leading to short response times. After cessation of emissions VMSs concentrations in the environment are expected to decrease rapidly from current levels. Response times in specific water and sediment systems were evaluated using a dynamic QWASI model. Response times were sensitive to both physico-chemical properties and environmental characteristics. Degradation was predicted to play the most important role in determining response times in water and sediment. In the case of the lowest molecular weight VMSs such as L2 and D3, response times were essentially independent of environmental characteristics due to fast hydrolysis in water and sediment. However, response times for the other VMSs are system-specific. They are relatively short in shallow water bodies but increase with depth due to the diminishing role of volatilization on concentration change as volume to surface area ratio increases. In sediment, degradation and resuspension rates also contribute most to the response times. The estimated response times for local environments are useful for planning future monitoring programs.
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Affiliation(s)
- Jaeshin Kim
- Toxicology and Environmental Research and Consulting, The Dow Chemical Company, Midland, MI, USA.
| | - Donald Mackay
- Department of Chemistry, Trent University, Peterborough, ON, Canada
| | - Michael John Whelan
- School of Geography, Geology and the Environment, University of Leicester, Leicester LE1 7RH, United Kingdom
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126
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Chen J, Fine JD, Mullin CA. Are organosilicon surfactants safe for bees or humans? THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 612:415-421. [PMID: 28863372 DOI: 10.1016/j.scitotenv.2017.08.175] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 08/16/2017] [Accepted: 08/16/2017] [Indexed: 06/07/2023]
Abstract
Organosilicon surfactants are the most potent adjuvants available for formulating and applying agricultural pesticides and fertilizers, household cleaning and personal care products, dental impressions and medicines. Risk assessment of pesticides, drugs or personal care products that takes into account only active ingredients without the other formulation ingredients and adjuvants commonly used in their application will miss important toxicity outcomes detrimental to non-target species including pollinators and humans. Over a billion pounds of organosilicon surfactants from all uses are produced globally per year, making this a major component of the chemical landscape to which bees and humans are exposed. These silicones, like most "inerts", are generally recognized as safe, have no mandated tolerances, and their residues are largely unmonitored. Lack of their public disclosure and adequate analytical methods constrains evaluation of their risk. Organosilicon surfactants, the most super-spreading and -penetrating adjuvants available, at relevant exposure levels impair honey bee learning, are acutely toxic, and in combination with bee viruses cause synergistic mortality. Organosilicon surfactants need to be regulated as a separate class of "inerts" from the more common silicones. In turn, impacts of organosilicon surfactant exposures on humans need to be evaluated. Silicones in their great diversity probably represent the single most ubiquitous environmental class of global synthetic pollutants. Do honey bees, a model environmental indicator organism, forewarn of hidden risks to humans of ubiquitous silicone exposures?
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Affiliation(s)
- Jing Chen
- School of Chemistry and Chemical Engineering, Shandong University, Jinan, Shandong 250100, China; Suzhou Institute of Shandong University, Suzhou, Jiangsu 215123, China.
| | - Julia D Fine
- Carl R. Woese Institute for Genomic Biology, University of Illinois Urbana-Champaign, 1206 W Gregory Dr., Urbana, IL 61801, USA.
| | - Christopher A Mullin
- Department of Entomology, Center for Pollinator Research, The Pennsylvania State University, University Park, PA 16802, USA.
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127
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Mojsiewicz-Pieńkowska K, Krenczkowska D. Evolution of consciousness of exposure to siloxanes-review of publications. CHEMOSPHERE 2018; 191:204-217. [PMID: 29035792 DOI: 10.1016/j.chemosphere.2017.10.045] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 10/06/2017] [Accepted: 10/07/2017] [Indexed: 06/07/2023]
Abstract
The purpose of this description is to review scientific literature from 1944 to 2017 as a source of information on the reasons for the increased interest in siloxanes (silicones). Not only the research area, but first, the changes in the tendency of research aims are important issues in the evaluation. On the one hand, the authors emphasize the unique properties of linear and cyclic siloxanes, providing many examples of beneficial applications, and on the other hand, there are some warnings of overcoming of the safety barrier of their presence in human environment. Analyzing the results from the SCOPUS database, it can be argued that the increased interest of scientists and government agencies particularly relates to the analysis of siloxanes in biological and environmental samples. This is caused not only by the widespread use of various siloxanes in the pharmaceutical, medical, cosmetic and food industries, but also by the direct contact of these compounds with tissues, as well as an increased access to knowledge and modern research tools that have developed the awareness of hazards. The development of research methods enables not only constant monitoring of progressively lower siloxanes concentrations in various samples, but because of the specificity of these methods, it also enables an identification of specific siloxane compounds and evaluation of their effects on humans and environment. This paper discusses the issues of the evolution of consciousness of exposure to siloxanes due to their increased synthesis and widespread use in many areas of human life, which contributes to environmental pollution.
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Affiliation(s)
- Krystyna Mojsiewicz-Pieńkowska
- Department of Physical Chemistry, Faculty of Pharmacy with Subfaculty of Laboratory Medicine, Medical University of Gdańsk, 80-416 Gdańsk, Al. Gen. Hallera 107, Poland.
| | - Dominika Krenczkowska
- Department of Physical Chemistry, Faculty of Pharmacy with Subfaculty of Laboratory Medicine, Medical University of Gdańsk, 80-416 Gdańsk, Al. Gen. Hallera 107, Poland
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128
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Lin SY, Wang MR, Chiu SJ, Lin CY, Hu TM. S-Nitrosothiols (SNO) as light-responsive molecular activators for post-synthesis fluorescence augmentation in fluorophore-loaded nanospheres. J Mater Chem B 2018; 6:153-164. [DOI: 10.1039/c7tb02233f] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
For the first time S-nitrosothiol is engineered into fluorophore-loaded silica nanospheres for post-synthesis, light-triggered fluorescence augmentation.
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Affiliation(s)
- Shu-Yi Lin
- School of Pharmacy, National Defense Medical Center
- Taipei
- Republic of China
| | - Meng-Ren Wang
- School of Pharmacy, National Defense Medical Center
- Taipei
- Republic of China
| | - Shih-Jiuan Chiu
- School of Pharmacy, Taipei Medical University
- Taipei
- Republic of China
| | - Chien-Yu Lin
- Faculty of Pharmacy, School of Pharmaceutical Sciences, National Yang-Ming University
- Taipei
- Republic of China
| | - Teh-Min Hu
- School of Pharmacy, National Defense Medical Center
- Taipei
- Republic of China
- Faculty of Pharmacy, School of Pharmaceutical Sciences, National Yang-Ming University
- Taipei
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129
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Levitsky MM, Bilyachenko AN, Shul'pin GB. Oxidation of C-H compounds with peroxides catalyzed by polynuclear transition metal complexes in Si- or Ge-sesquioxane frameworks: A review. J Organomet Chem 2017. [DOI: 10.1016/j.jorganchem.2017.05.007] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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130
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Yuan B, Koss AR, Warneke C, Coggon M, Sekimoto K, de Gouw JA. Proton-Transfer-Reaction Mass Spectrometry: Applications in Atmospheric Sciences. Chem Rev 2017; 117:13187-13229. [DOI: 10.1021/acs.chemrev.7b00325] [Citation(s) in RCA: 191] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Bin Yuan
- Institute
for Environment and Climate Research, Jinan University, Guangzhou 510632, China
- Chemical
Sciences Division, NOAA Earth System Research Laboratory (ESRL), Boulder, Colorado 80305, United States
- Cooperative
Institute for Research in Environmental Sciences, University of Colorado at Boulder, Boulder, Colorado 80309, United States
- Laboratory
of Atmospheric Chemistry, Paul Scherrer Institute, Villigen 5232, Switzerland
| | - Abigail R. Koss
- Chemical
Sciences Division, NOAA Earth System Research Laboratory (ESRL), Boulder, Colorado 80305, United States
- Cooperative
Institute for Research in Environmental Sciences, University of Colorado at Boulder, Boulder, Colorado 80309, United States
- Department
of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309, United States
| | - Carsten Warneke
- Chemical
Sciences Division, NOAA Earth System Research Laboratory (ESRL), Boulder, Colorado 80305, United States
- Cooperative
Institute for Research in Environmental Sciences, University of Colorado at Boulder, Boulder, Colorado 80309, United States
| | - Matthew Coggon
- Chemical
Sciences Division, NOAA Earth System Research Laboratory (ESRL), Boulder, Colorado 80305, United States
- Cooperative
Institute for Research in Environmental Sciences, University of Colorado at Boulder, Boulder, Colorado 80309, United States
| | - Kanako Sekimoto
- Chemical
Sciences Division, NOAA Earth System Research Laboratory (ESRL), Boulder, Colorado 80305, United States
- Graduate
School of Nanobioscience, Yokohama City University, Yokohama 236-0027, Japan
| | - Joost A. de Gouw
- Cooperative
Institute for Research in Environmental Sciences, University of Colorado at Boulder, Boulder, Colorado 80309, United States
- Department
of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309, United States
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131
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Martín-Fernández C, Montero-Campillo MM, Alkorta I, Elguero J. Modulating the Proton Affinity of Silanol and Siloxane Derivatives by Tetrel Bonds. J Phys Chem A 2017; 121:7424-7431. [DOI: 10.1021/acs.jpca.7b07886] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Carlos Martín-Fernández
- Instituto
de Química Médica, CSIC, Juan de la Cierva, 3, 28006 Madrid, Spain
- Department
of Chemistry, KU Leuven, Celestijnenlaan, 200F, 3001 Leuven, Belgium
| | | | - Ibon Alkorta
- Instituto
de Química Médica, CSIC, Juan de la Cierva, 3, 28006 Madrid, Spain
| | - José Elguero
- Instituto
de Química Médica, CSIC, Juan de la Cierva, 3, 28006 Madrid, Spain
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132
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Lu Z, Martin PA, Burgess NM, Champoux L, Elliott JE, Baressi E, De Silva AO, de Solla SR, Letcher RJ. Volatile Methylsiloxanes and Organophosphate Esters in the Eggs of European Starlings (Sturnus vulgaris) and Congeneric Gull Species from Locations across Canada. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:9836-9845. [PMID: 28771368 DOI: 10.1021/acs.est.7b03192] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Volatile methylsiloxanes (VMSs) and organophosphate esters (OPEs) are two suites of chemicals that are of environmental concern as organic contaminants, but little is known about the exposure of wildlife to these contaminants, particularly in birds, in terrestrial and aquatic ecosystems. The present study investigates the spatial distributions of nine cyclic and linear VMSs and 17 OPEs in the eggs of European starlings (Sturnus vulgaris) and three congeneric gull species (i.e., herring gull (Larus argentatus), glaucous-winged gull (L. glaucescens), and California gull (L. californicus)) from nesting sites across Canada. ∑VMS concentrations for all bird eggs were dominated by decamethylcyclopentasiloxane (D5), dodecamethylcyclohexasiloxane (D6), and octamethylcyclotetrasiloxane (D4). With European starlings, birds breeding adjacent to landfill sites had eggs containing significantly greater ∑VMS concentrations (median: 178 ng g-1 wet weight (ww)) compared with those from the urban industrial (20 ng g-1 ww) and rural sites (1.3 ng g-1 ww), indicating that the landfills are important sources of VMSs to Canadian terrestrial environments. In gull eggs, the median ∑VMS concentrations were up to 254 ng g-1 ww and suggested greater detection frequencies and levels of VMSs in aquatic- versus terrestrial-feeding birds in Canada. In contrast, the detection frequency of OPEs in all European starling and gull eggs was lower than 16%. This suggested that low dietary exposure or rapid metabolism of accumulated OPEs occurs in aquatic feeding birds and may warrant further investigation for the elucidation of the reasons for these differences.
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Affiliation(s)
| | | | - Neil M Burgess
- Ecotoxicology and Wildlife Health Division, Environment and Climate Change Canada , Mount Pearl, Newfoundland and Labrador A1N 4T3, Canada
| | - Louise Champoux
- Ecotoxicology and Wildlife Health Division, Environment and Climate Change Canada , Québec City, Québec G1J 0C3, Canada
| | - John E Elliott
- Ecotoxicology and Wildlife Health Division, Environment and Climate Change Canada, Pacific Wildlife Research Centre , Delta, British Columbia V4K 3Y3, Canada
| | - Enzo Baressi
- National Laboratory of Environmental Testing, Environment and Climate Change Canada , Burlington, Ontario L7S 1A1, Canada
| | | | | | - Robert J Letcher
- Ecotoxicology and Wildlife Health Division, Environment and Climate Change Canada, National Wildlife Research Centre, Carleton University , Ottawa, Ontario K1A 0H3, Canada
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133
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Janechek NJ, Hansen KM, Stanier CO. Comprehensive atmospheric modeling of reactive cyclic siloxanes and their oxidation products. ATMOSPHERIC CHEMISTRY AND PHYSICS 2017; 17:8357-8370. [PMID: 30740128 PMCID: PMC6368090 DOI: 10.5194/acp-17-8357-2017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Cyclic volatile methyl siloxanes (cVMSs) are important components in personal care products that transport and react in the atmosphere. Octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), dodecamethylcyclohexasiloxane (D6), and their gas-phase oxidation products have been incorporated into the Community Multiscale Air Quality (CMAQ) model. Gas-phase oxidation products, as the precursor to secondary organic aerosol from this compound class, were included to quantify the maximum potential for aerosol formation from gas-phase reactions with OH. Four 1-month periods were modeled to quantify typical concentrations, seasonal variability, spatial patterns, and vertical profiles. Typical model concentrations showed parent compounds were highly dependent on population density as cities had monthly averaged peak D5 concentrations up to 432ngm-3. Peak oxidized D5 concentrations were significantly less, up to 9ngm-3, and were located downwind of major urban areas. Model results were compared to available measurements and previous simulation results. Seasonal variation was analyzed and differences in seasonal influences were observed between urban and rural locations. Parent compound concentrations in urban and peri-urban locations were sensitive to transport factors, while parent compounds in rural areas and oxidized product concentrations were influenced by large-scale seasonal variability in OH.
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Affiliation(s)
- Nathan J. Janechek
- Department of Chemical and Biochemical Engineering, University of Iowa, Iowa City, IA 52242, USA
- IIHR Hydroscience and Engineering, University of Iowa, Iowa City, IA 52242, USA
| | - Kaj M. Hansen
- Department of Environmental Science, Aarhus University, Roskilde, Denmark
| | - Charles O. Stanier
- Department of Chemical and Biochemical Engineering, University of Iowa, Iowa City, IA 52242, USA
- IIHR Hydroscience and Engineering, University of Iowa, Iowa City, IA 52242, USA
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134
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Cui X, Junge K, Dai X, Kreyenschulte C, Pohl MM, Wohlrab S, Shi F, Brückner A, Beller M. Synthesis of Single Atom Based Heterogeneous Platinum Catalysts: High Selectivity and Activity for Hydrosilylation Reactions. ACS CENTRAL SCIENCE 2017; 3:580-585. [PMID: 28691069 PMCID: PMC5492251 DOI: 10.1021/acscentsci.7b00105] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Indexed: 05/30/2023]
Abstract
Catalytic hydrosilylation represents a straightforward and atom-efficient methodology for the creation of C-Si bonds. In general, the application of homogeneous platinum complexes prevails in industry and academia. Herein, we describe the first heterogeneous single atom catalysts (SACs), which are conveniently prepared by decorating alumina nanorods with platinum atoms. The resulting stable material efficiently catalyzes hydrosilylation of industrially relevant olefins with high TON (≈105). A variety of substrates is selectively hydrosilylated including compounds with sensitive reducible and other functional groups (N, B, F, Cl). The single atom based catalyst shows significantly higher activity compared to related Pt nanoparticles.
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Affiliation(s)
- Xinjiang Cui
- Leibniz-Institut
für Katalyse e.V. an der Universität Rostock, Albert-Einstein Straße 29a, Rostock, 18059, Germany
| | - Kathrin Junge
- Leibniz-Institut
für Katalyse e.V. an der Universität Rostock, Albert-Einstein Straße 29a, Rostock, 18059, Germany
| | - Xingchao Dai
- State
Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou
Institute of Chemical Physics, Chinese Academy
of Sciences, No. 18,
Tianshui Middle Road, Lanzhou, 730000, China
| | - Carsten Kreyenschulte
- Leibniz-Institut
für Katalyse e.V. an der Universität Rostock, Albert-Einstein Straße 29a, Rostock, 18059, Germany
| | - Marga-Martina Pohl
- Leibniz-Institut
für Katalyse e.V. an der Universität Rostock, Albert-Einstein Straße 29a, Rostock, 18059, Germany
| | - Sebastian Wohlrab
- Leibniz-Institut
für Katalyse e.V. an der Universität Rostock, Albert-Einstein Straße 29a, Rostock, 18059, Germany
| | - Feng Shi
- State
Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou
Institute of Chemical Physics, Chinese Academy
of Sciences, No. 18,
Tianshui Middle Road, Lanzhou, 730000, China
| | - Angelika Brückner
- Leibniz-Institut
für Katalyse e.V. an der Universität Rostock, Albert-Einstein Straße 29a, Rostock, 18059, Germany
| | - Matthias Beller
- Leibniz-Institut
für Katalyse e.V. an der Universität Rostock, Albert-Einstein Straße 29a, Rostock, 18059, Germany
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135
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Abstract
The family of silicatein enzymes from marine sponges (phylum Porifera) is unique in nature for catalyzing the formation of inorganic silica structures, which the organisms incorporate into their skeleton. However, the synthesis of organosiloxanes catalyzed by these enzymes has thus far remained largely unexplored. To investigate the reactivity of these enzymes in relation to this important class of compounds, their catalysis of Si-O bond hydrolysis and condensation was investigated with a range of model organosilanols and silyl ethers. The enzymes' kinetic parameters were obtained by a high-throughput colorimetric assay based on the hydrolysis of 4-nitrophenyl silyl ethers. These assays showed unambiguous catalysis with kcat/Km values on the order of 2-50 min-1 μM-1 Condensation reactions were also demonstrated by the generation of silyl ethers from their corresponding silanols and alcohols. Notably, when presented with a substrate bearing both aliphatic and aromatic hydroxy groups the enzyme preferentially silylates the latter group, in clear contrast to nonenzymatic silylations. Furthermore, the silicateins are able to catalyze transetherifications, where the silyl group from one silyl ether may be transferred to a recipient alcohol. Despite close sequence homology to the protease cathepsin L, the silicateins seem to exhibit no significant protease or esterase activity when tested against analogous substrates. Overall, these results suggest the silicateins are promising candidates for future elaboration into efficient and selective biocatalysts for organosiloxane chemistry.
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136
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Affiliation(s)
- Krzysztof Kuciński
- Faculty of Chemistry; Adam Mickiewicz University in Poznań; Umultowska 89b 61-614 Poznań Poland
| | - Grzegorz Hreczycho
- Faculty of Chemistry; Adam Mickiewicz University in Poznań; Umultowska 89b 61-614 Poznań Poland
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137
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Kim J, Mackay D, Powell DE. Roles of steady-state and dynamic models for regulation of hydrophobic chemicals in aquatic systems: A case study of decamethylcyclopentasiloxane (D5) and PCB-180 in three diverse ecosystems. CHEMOSPHERE 2017; 175:253-268. [PMID: 28226279 DOI: 10.1016/j.chemosphere.2017.02.050] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 02/06/2017] [Accepted: 02/08/2017] [Indexed: 06/06/2023]
Abstract
We seek to contribute to the improved regulatory use of mass balance models to complement environmental monitoring data by applying the steady-state Quantitative Water Air Sediment Interactive model (QWASI) and a novel unsteady-state QWASI model. A steady-state model can yield not only a useful simulation of chemical fate under near steady-state conditions, but it can provide insights into the likely influences of increasing or decreasing emission rates, temperature changes, and unexpectedly high sensitivities to model parameters that may require additional investigation. We compared the consistency of insights from both types of model, in the expectation that while the dynamic model provides a closer simulation of actual conditions, for many purposes a simple, less computationally demanding, more transparent and less expensive model may be adequate for many regulatory purposes. We investigated the response times of decamethylcyclopentasiloxane (D5) and PCB-180 concentrations in water and sediment under three emission scenarios in three different aquatic systems, namely Lake Ontario, Oslofjord, and Lake Pepin. D5 was predicted to be removed largely by hydrolysis and volatilization in Lake Ontario and Oslofjord whereas it is subject to removal by advective loss in Lake Pepin. The half-times of D5 water concentration to a stepwise reduction in emission were <60 days in all three water bodies. In contrast, the predicted half-times were 0.53, 1.4, and 2.9 years in Lake Pepin, Oslofjord, and Lake Ontario, respectively. We also explored how uncertainties in input parameters propagate into uncertainties of concentrations in water and sediments possibly necessitating more accurate values.
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Affiliation(s)
- Jaeshin Kim
- Toxicology and Environmental Research and Consulting, The Dow Chemical Company, Midland, MI, USA.
| | - Donald Mackay
- Canadian Centre for Environmental Modelling and Chemistry, Trent University, Peterborough, ON, Canada
| | - David E Powell
- Toxicology and Environmental Research and Consulting, The Dow Chemical Company, Midland, MI, USA
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138
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Capela D, Ratola N, Alves A, Homem V. Volatile methylsiloxanes through wastewater treatment plants - A review of levels and implications. ENVIRONMENT INTERNATIONAL 2017; 102:9-29. [PMID: 28325665 DOI: 10.1016/j.envint.2017.03.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 01/31/2017] [Accepted: 03/05/2017] [Indexed: 06/06/2023]
Abstract
The use of siloxanes has been increasing due to physicochemical properties that are appropriate to be included in the formulations of a large variety of consumer products. This implies a considerable release of these chemicals into the environment, which caught the attention of the scientific community in view of some reports of potential hazardous effects. However, the studies related to the presence and partition of volatile methylsiloxanes (VMSs) in wastewater treatment plants (WWTPs) are still scarce. The aim of this review is to provide a comprehensive assessment of the current state of the knowledge concerning the presence of VMSs in WWTPs and also a discussion of the efficiency of the removal technologies available. Levels, fate and behaviour of VMSs in WWTPs were reviewed, covering not only the water and sludge lines during the treatment processes, but also in the surrounding air. Several approaches for the analysis of VMSs within the WWTPs have been developed to cope with the complexity of the mentioned matrices, which led to sometimes challenging protocols. Hence, an overview of methodologies normally used was also included in the present review. Regarding the wastewater samples, VMSs have been detected in influents in concentrations ranging from a few nanograms to a hundred micrograms per litre, in which linear VMSs were usually detected in lower levels than cyclic siloxanes. The levels of VMSs in effluents were lower than those found in influents, suggesting an effective removal from the water line. However, they are commonly accumulating in the sludge, instead of suffering degradation during the treatment process. Therefore, due to the volatile character of VMSs it can be expected that a fraction may be removed in WWTPs by volatilization, thus completing the mass balances to the whole treatment facilities.
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Affiliation(s)
- Daniela Capela
- LEPABE-Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Nuno Ratola
- LEPABE-Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Arminda Alves
- LEPABE-Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Vera Homem
- LEPABE-Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.
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139
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Kuhn JN, Elwell AC, Elsayed NH, Joseph B. Requirements, techniques, and costs for contaminant removal from landfill gas. WASTE MANAGEMENT (NEW YORK, N.Y.) 2017; 63:246-256. [PMID: 28209243 DOI: 10.1016/j.wasman.2017.02.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 01/31/2017] [Accepted: 02/01/2017] [Indexed: 06/06/2023]
Abstract
Waste-to-energy projects are an increasingly prominent component of future energy portfolios. Landfill gas (LFG)-to-energy (LFGTE) projects are particularly important as they address greenhouse gas emissions. Contaminants in LFG may hamper these projects both from environmental and economic standpoints. The purpose of this review is to highlight key aspects (LFG composition ranges, LFG flowrates, and allowable tolerances for LFGTE technologies, performance and costs for contaminant removal by adsorption). Removal of key contaminants, H2S and siloxanes, by adsorption are surveyed in terms of adsorption capacities and regeneration abilities. Based on the open literature, costing analyses are tabulated and discussed. The findings indicate economics of contaminant removal depend heavily on the feed concentrations of contaminants, allowable tolerances for the LFGTE technology, and the current market for the product. Key trends, identification of challenges, and general purification guidelines for purifying LFG for energy projects are also discussed.
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Affiliation(s)
- John N Kuhn
- Department of Chemical & Biomedical Engineering, University of South Florida, Tampa, FL 33620, United States; T2C-Energy, LLC, 3802 Spectrum Blvd Suite 128p, Tampa, FL 33612, United States.
| | - Anthony C Elwell
- Department of Chemical & Biomedical Engineering, University of South Florida, Tampa, FL 33620, United States
| | - Nada H Elsayed
- Department of Chemical & Biomedical Engineering, University of South Florida, Tampa, FL 33620, United States
| | - Babu Joseph
- Department of Chemical & Biomedical Engineering, University of South Florida, Tampa, FL 33620, United States; T2C-Energy, LLC, 3802 Spectrum Blvd Suite 128p, Tampa, FL 33612, United States
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140
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Toya Y, Hayasaka K, Nakazawa H. Hydrosilylation of Olefins Catalyzed by Iron Complexes Bearing Ketimine-Type Iminobipyridine Ligands. Organometallics 2017. [DOI: 10.1021/acs.organomet.7b00087] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Yuki Toya
- Department of Chemistry,
Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Kazumasa Hayasaka
- Department of Chemistry,
Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Hiroshi Nakazawa
- Department of Chemistry,
Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan
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141
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Homem V, Capela D, Silva JA, Cincinelli A, Santos L, Alves A, Ratola N. An approach to the environmental prioritisation of volatile methylsiloxanes in several matrices. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 579:506-513. [PMID: 27871757 DOI: 10.1016/j.scitotenv.2016.11.068] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2015] [Revised: 10/19/2016] [Accepted: 11/11/2016] [Indexed: 06/06/2023]
Abstract
Siloxane-based compounds are widely used in personal care, pharmaceutical and household products as well as in industrial applications. Among the wide variety of these chemicals, special attention has been given to volatile methylsiloxanes (VMSs). These compounds have been extensively detected in several environmental compartments, as they are not effectively removed from wastewater and may migrate through different matrices and being lipophilic, bioaccumulate and biomagnify in living organisms. In this work, a prioritisation methodology for several VMSs in different environmental matrices was applied, estimating a hazard quotient by combining exposure evaluation through measured or predicted environmental concentrations (MEC or PEC) and effects using ecotoxicity data to establish no effect concentrations (PNEC). VMSs show quite different hazard potentials in the environment: for linear VMSs it is not considerable, while for cyclic VMSs the hazard is disperse. D4 and D5 may have adverse effects in water, as well as D5 and D6 in sediments. This first multi-matrix approach for the prioritisation of VMSs sets the ground for more accurate studies in the future, provided that more field-based data are reported.
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Affiliation(s)
- Vera Homem
- LEPABE-Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.
| | - Daniela Capela
- LEPABE-Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - José Avelino Silva
- LEPABE-Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | | | - Lúcia Santos
- LEPABE-Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Arminda Alves
- LEPABE-Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Nuno Ratola
- LEPABE-Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
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142
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Fine JD, Cox-Foster DL, Mullin CA. An Inert Pesticide Adjuvant Synergizes Viral Pathogenicity and Mortality in Honey Bee Larvae. Sci Rep 2017; 7:40499. [PMID: 28091574 PMCID: PMC5238421 DOI: 10.1038/srep40499] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Accepted: 12/07/2016] [Indexed: 11/09/2022] Open
Abstract
Honey bees are highly valued for their pollination services in agricultural settings, and recent declines in managed populations have caused concern. Colony losses following a major pollination event in the United States, almond pollination, have been characterized by brood mortality with specific symptoms, followed by eventual colony loss weeks later. In this study, we demonstrate that these symptoms can be produced by chronically exposing brood to both an organosilicone surfactant adjuvant (OSS) commonly used on many agricultural crops including wine grapes, tree nuts and tree fruits and exogenous viral pathogens by simulating a horizontal transmission event. Observed synergistic mortality occurred during the larval-pupal molt. Using q-PCR techniques to measure gene expression and viral levels in larvae taken prior to observed mortality at metamorphosis, we found that exposure to OSS and exogenous virus resulted in significantly heightened Black Queen Cell Virus (BQCV) titers and lower expression of a Toll 7-like-receptor associated with autophagic viral defense (Am18w). These results demonstrate that organosilicone spray adjuvants that are considered biologically inert potentiate viral pathogenicity in honey bee larvae, and guidelines for OSS use may be warranted.
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Affiliation(s)
- Julia D Fine
- Department of Entomology, Center for Pollinator Research, The Pennsylvania State University, University Park, PA 16802, USA
| | - Diana L Cox-Foster
- Department of Entomology, Center for Pollinator Research, The Pennsylvania State University, University Park, PA 16802, USA.,USDA-ARS-PWA Pollinating Insect Research Unit, Logan, UT 84322, USA
| | - Christopher A Mullin
- Department of Entomology, Center for Pollinator Research, The Pennsylvania State University, University Park, PA 16802, USA
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143
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Neumeyer F, Auner N. One-Step Synthesis of Siloxanes from the Direct Process Disilane Residue. Chemistry 2016; 22:17165-17168. [PMID: 27739108 DOI: 10.1002/chem.201603842] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Indexed: 11/08/2022]
Abstract
The well-established Müller-Rochow Direct Process for the chloromethylsilane synthesis produces a disilane residue (DPR) consisting of compounds Men Si2 Cl6-n (n=1-6) in thousands of tons annually. Technologically, much effort is made to retransfer the disilanes into monosilanes suitable for introduction into the siloxane production chain for increase in economic value. Here, we report on a single step reaction to directly form cyclic, linear, and cage-like siloxanes upon treatment of the DPR with a 5 m HCl in Et2 O solution at about 120 °C for 60 h. For simplification of the Si-Si bond cleavage and aiming on product selectivity the grade of methylation at the silicon backbone is increased to n≥4. Moreover, the HCl/Et2 O reagent is also suitable to produce siloxanes from the corresponding monosilanes under comparable conditions.
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Affiliation(s)
- Felix Neumeyer
- Institut für Anorganische Chemie, Goethe-Universität, Max-von-Laue-Straße 7, 60438, Frankfurt/Main, Germany
| | - Norbert Auner
- Institut für Anorganische Chemie, Goethe-Universität, Max-von-Laue-Straße 7, 60438, Frankfurt/Main, Germany
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144
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Cheng C, Watts A, Hillmyer MA, Hartwig JF. Polysilylether: A Degradable Polymer from Biorenewable Feedstocks. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201606282] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Chen Cheng
- Department of Chemistry University of California Berkeley CA 94720 USA
| | - Annabelle Watts
- Department of Chemistry University of Minnesota Minneapolis MN 55455 USA
| | - Marc A. Hillmyer
- Department of Chemistry University of Minnesota Minneapolis MN 55455 USA
| | - John F. Hartwig
- Department of Chemistry University of California Berkeley CA 94720 USA
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145
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Kulyk K, Zettergren H, Gatchell M, Alexander JD, Borysenko M, Palianytsia B, Larsson M, Kulik T. Dimethylsilanone Generation from Pyrolysis of Polysiloxanes Filled with Nanosized Silica and Ceria/Silica. Chempluschem 2016; 81:1003-1013. [PMID: 31968802 DOI: 10.1002/cplu.201600229] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 06/06/2016] [Indexed: 11/11/2022]
Abstract
Temperature-programmed desorption mass spectrometry (TPD MS) was used to study the pyrolysis of PDMS and its composites with nanosized silica and ceria/silica. The results suggest that the elusive organosilicon compound, dimethylsilanone, is generated from PDMS over a broad temperature range (in some cases starting at 70 °C). The presence of nano-oxides catalyzes this process. Ions characteristic of the fragmentation of dimethylsilanone under electron ionization are assigned with the aid of DFT structure calculations. Possible reaction mechanisms for dimethylsilanone generation are discussed in the context of the calculated kinetic parameters. Observed accompanying products of PDMS pyrolysis, such as tetramethylcyclodisiloxane and hexamethylcyclotrisiloxane, indicate that multiple channels are involved in the dimethylsilanone release.
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Affiliation(s)
- Kostiantyn Kulyk
- Department of Physics, Stockholm University, 106 91, Stockholm, Sweden
| | | | - Michael Gatchell
- Department of Physics, Stockholm University, 106 91, Stockholm, Sweden
| | - John D Alexander
- Department of Physics, Stockholm University, 106 91, Stockholm, Sweden
| | - Mykola Borysenko
- Chuiko Institute of Surface Chemistry, National Academy of Sciences of Ukraine, 17 General Naumov Street, 03164, Kyiv, Ukraine
| | - Borys Palianytsia
- Chuiko Institute of Surface Chemistry, National Academy of Sciences of Ukraine, 17 General Naumov Street, 03164, Kyiv, Ukraine
| | - Mats Larsson
- Department of Physics, Stockholm University, 106 91, Stockholm, Sweden
| | - Tetiana Kulik
- Chuiko Institute of Surface Chemistry, National Academy of Sciences of Ukraine, 17 General Naumov Street, 03164, Kyiv, Ukraine
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146
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Cheng C, Watts A, Hillmyer MA, Hartwig JF. Polysilylether: A Degradable Polymer from Biorenewable Feedstocks. Angew Chem Int Ed Engl 2016; 55:11872-6. [DOI: 10.1002/anie.201606282] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Indexed: 11/11/2022]
Affiliation(s)
- Chen Cheng
- Department of Chemistry University of California Berkeley CA 94720 USA
| | - Annabelle Watts
- Department of Chemistry University of Minnesota Minneapolis MN 55455 USA
| | - Marc A. Hillmyer
- Department of Chemistry University of Minnesota Minneapolis MN 55455 USA
| | - John F. Hartwig
- Department of Chemistry University of California Berkeley CA 94720 USA
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147
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Funke S, Matilainen J, Nalenz H, Bechtold-Peters K, Mahler HC, Vetter F, Müller C, Bracher F, Friess W. Optimization of the bake-on siliconization of cartridges. Part II: Investigations into burn-in time and temperature. Eur J Pharm Biopharm 2016; 105:209-22. [DOI: 10.1016/j.ejpb.2016.05.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 05/13/2016] [Accepted: 05/18/2016] [Indexed: 11/27/2022]
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148
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Capela D, Alves A, Homem V, Santos L. From the shop to the drain - Volatile methylsiloxanes in cosmetics and personal care products. ENVIRONMENT INTERNATIONAL 2016; 92-93:50-62. [PMID: 27058927 DOI: 10.1016/j.envint.2016.03.016] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Revised: 03/15/2016] [Accepted: 03/15/2016] [Indexed: 05/06/2023]
Abstract
Organosiloxanes are widely used in the formulation of a broad range of cosmetic and personal care products (PCPs), including creams and lotions, bath soaps, shampoo and hair care products to soften, smooth, and moisten. In fact, the intensive and widespread use of organosiloxanes combined with their lipophilic nature, makes them interesting targets for future research, particularly in the toxicology area. This study focused on determining the concentration levels of these compounds in the bestselling brands of PCPs in the Oporto region (Portugal), allowing the estimation of dermal and inhalation exposure to siloxanes and the evaluation of the quantities released to the environment "down-the-drain" and to air. To accomplish this task, a QuEChERS technique ("Quick, Easy, Cheap, Effective, Rugged, and Safe") was employed to extract the siloxanes from the target PCPs, which has never been tested before. The resulting extract was analysed by gas chromatography-mass spectrometry (GC-MS). The limits of detection varied between 0.17 (L2) and 3.75ngg(-1) (L5), being much lower than any values reported in the literature for this kind of products. In general, satisfactory precision (<10%) and accuracy values (average recovery of 84%) were obtained. 123 PCPs were analysed (moisturizers, deodorants, body and hair washes, toilet soaps, toothpastes and shaving products) and volatile methylsiloxanes were detected in 96% of the samples, in concentrations between 0.003μgg(-1) and 1203μgg(-1). Shampoo exhibited the highest concentration for cyclic and aftershaves for linear siloxanes. Combining these results with the daily usage amounts, an average daily dermal exposure of 25.04μgkgbw(-1)day(-1) for adults and 0.35μgkgbw(-1)day(-1) for baby/children was estimated. The main contributors for adult dermal exposure were body moisturizers, followed by facial creams and aftershaves, while for babies/children were body moisturizers, followed by shower gel and shampoo. Similarly, the average daily inhalation exposure was also estimated. Values of 1.56μgkgbw(-1)day(-1) for adults and 0.03μgkgbw(-1)day(-1) for babies/children were calculated. An estimate of the siloxanes amount released "down-the-drain" into the sewage systems through the use of toiletries was also performed. An emission per capita between 49.25 and 9574μgday(-1) (mean: 1817μgday(-1)) is expected and shampoo and shower gel presented the higher mean total values (1008μgday(-1) and 473.3μgday(-1), respectively). In the worst-case scenario, D5 and D3 were the predominant siloxanes in the effluents with 3336μgday(-1) and 3789μgday(-1), respectively. Regarding the air emissions per capita, values between 8.33 and 6109μgday(-1) (mean: 1607μgday(-1)) are expected and D5 and D6 were the predominant siloxanes.
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Affiliation(s)
- Daniela Capela
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Arminda Alves
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Vera Homem
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.
| | - Lúcia Santos
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
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149
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Mullin CA, Fine JD, Reynolds RD, Frazier MT. Toxicological Risks of Agrochemical Spray Adjuvants: Organosilicone Surfactants May Not Be Safe. Front Public Health 2016; 4:92. [PMID: 27242985 PMCID: PMC4862968 DOI: 10.3389/fpubh.2016.00092] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 04/25/2016] [Indexed: 01/31/2023] Open
Abstract
Agrochemical risk assessment that takes into account only pesticide active ingredients without the spray adjuvants commonly used in their application will miss important toxicity outcomes detrimental to non-target species, including humans. Lack of disclosure of adjuvant and formulation ingredients coupled with a lack of adequate analytical methods constrains the assessment of total chemical load on beneficial organisms and the environment. Adjuvants generally enhance the pesticidal efficacy and inadvertently the non-target effects of the active ingredient. Spray adjuvants are largely assumed to be biologically inert and are not registered by the USA EPA, leaving their regulation and monitoring to individual states. Organosilicone surfactants are the most potent adjuvants and super-penetrants available to growers. Based on the data for agrochemical applications to almonds from California Department of Pesticide Regulation, there has been increasing use of adjuvants, particularly organosilicone surfactants, during bloom when two-thirds of USA honey bee colonies are present. Increased tank mixing of these with ergosterol biosynthesis inhibitors and other fungicides and with insect growth regulator insecticides may be associated with recent USA honey bee declines. This database archives every application of a spray tank adjuvant with detail that is unprecedented globally. Organosilicone surfactants are good stand alone pesticides, toxic to bees, and are also present in drug and personal care products, particularly shampoos, and thus represent an important component of the chemical landscape to which pollinators and humans are exposed. This mini review is the first to possibly link spray adjuvant use with declining health of honey bee populations.
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Affiliation(s)
- Christopher A. Mullin
- Department of Entomology, Center for Pollinator Research, The Pennsylvania State University, University Park, PA, USA
| | - Julia D. Fine
- Department of Entomology, Center for Pollinator Research, The Pennsylvania State University, University Park, PA, USA
| | - Ryan D. Reynolds
- Department of Entomology, Center for Pollinator Research, The Pennsylvania State University, University Park, PA, USA
| | - Maryann T. Frazier
- Department of Entomology, Center for Pollinator Research, The Pennsylvania State University, University Park, PA, USA
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150
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Ratola N, Ramos S, Homem V, Silva JA, Jiménez-Guerrero P, Amigo JM, Santos L, Alves A. Using air, soil and vegetation to assess the environmental behaviour of siloxanes. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:3273-84. [PMID: 26490903 DOI: 10.1007/s11356-015-5574-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 10/07/2015] [Indexed: 05/06/2023]
Abstract
This study aimed to contribute to the enhancement of the knowledge of levels, trends and behaviour of eight siloxanes (four linear and four cyclic) in the environment. Adding to the prioritised scrutiny of the incidence in the atmosphere through passive samplers (sorbent-impregnated polyurethane foam disks--SIPs), the sampling of pine needles and soil was also performed, thus closing the circle of atmospheric exposure in the areas of study. Two sampling campaigns (one in summer and one in winter) were done in a total of eight sampling points in the Portuguese territory, which covered a wide range of human presence and land uses (urban, industrial, remote and beach areas). By adopting a "green" approach in terms of analytical methods, namely reducing the clean-up steps for the passive air samples and using the quick, easy, cheap, effective, rugged and safe (QuEChERS) technology for soils and pine needles, the results showed total concentration of siloxanes between 5 and 70 ng g(-1) (dry weight) for soils and from 2 to 118 ng g(-1) (dry weight (dw)) for pine needles, with no clear seasonal trend. For SIPs, the levels varied from 0.6 to 7.8 ng m(-3) and were higher in summer than in winter in all sites. Overall, the cyclic siloxanes were found in much higher concentrations, with D5 and D6 being the most predominant in a great majority of cases. Also, the urban and industrial areas had the highest incidence, suggesting a strong anthropogenic fingerprint, in line with their main uses.
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Affiliation(s)
- N Ratola
- LEPABE-DEQ, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, Porto, Portugal.
| | - S Ramos
- LEPABE-DEQ, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, Porto, Portugal
| | - V Homem
- LEPABE-DEQ, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, Porto, Portugal
| | - J A Silva
- LEPABE-DEQ, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, Porto, Portugal
| | - P Jiménez-Guerrero
- Physics of the Earth, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, Edificio CIOyN, Campus de Espinardo, 30100, Murcia, Spain
| | - J M Amigo
- Department of Food Science, Spectroscopy and Chemometrics, Faculty of Sciences, University of Copenhagen, Rolighedsvej 30, 1958, Frederiksberg C, Denmark
| | - L Santos
- LEPABE-DEQ, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, Porto, Portugal
| | - A Alves
- LEPABE-DEQ, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, Porto, Portugal
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