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Veeraswamy D, Subramanian A, Mohan D, Ettiyagounder P, Selvaraj PS, Ramasamy SP, Veeramani V. Exploring the origins and cleanup of mercury contamination: a comprehensive review. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:53943-53972. [PMID: 37964142 DOI: 10.1007/s11356-023-30636-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Accepted: 10/19/2023] [Indexed: 11/16/2023]
Abstract
Mercury is a global pollutant that poses significant risks to human health and the environment. Natural sources of mercury include volcanic eruptions, while anthropogenic sources include industrial processes, artisanal and small-scale gold mining, and fossil fuel combustion. Contamination can arise through various pathways, such as atmospheric deposition, water and soil contamination, bioaccumulation, and biomagnification in food chains. Various remediation strategies, including phytoremediation, bioremediation, chemical oxidation/reduction, and adsorption, have been developed to address mercury pollution, including physical, chemical, and biological approaches. The effectiveness of remediation techniques depends on the nature and extent of contamination and site-specific conditions. This review discusses the challenges associated with mercury pollution and remediation, including the need for effective monitoring and management strategies. Overall, this review offers a comprehensive understanding of mercury contamination and the range of remediation techniques available to mitigate its adverse impacts.
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Affiliation(s)
- Davamani Veeraswamy
- Department of Environmental Sciences, Directorate of Natural Resource Management, Tamil Nadu Agricultural University, Coimbatore, 641 003, Tamil Nadu, India
- College of Engineering, Science and Environment, Global Centre for Environmental Remediation (GCER), ATC Building, The University of Newcastle, Callaghan Campus, Callaghan, NSW, 2308, Australia
| | - Arulmani Subramanian
- Department of Chemistry, Bannari Amman Institute of Technology, Sathyamangalam, 638 401, Tamil Nadu, India.
| | - Deepasri Mohan
- Division of Environmental Sciences, Sher-E-Kashmir University of Agricultural Sciences and Technology, Shalimar, 190025, Jammu and Kashmir Union Territory, India
| | - Parameswari Ettiyagounder
- Department of Environmental Sciences, Directorate of Natural Resource Management, Tamil Nadu Agricultural University, Coimbatore, 641 003, Tamil Nadu, India
| | - Paul Sebastian Selvaraj
- Department of Environmental Sciences, Directorate of Natural Resource Management, Tamil Nadu Agricultural University, Coimbatore, 641 003, Tamil Nadu, India
- College of Engineering, Science and Environment, Global Centre for Environmental Remediation (GCER), ATC Building, The University of Newcastle, Callaghan Campus, Callaghan, NSW, 2308, Australia
| | - Sangeetha Piriya Ramasamy
- Department of Environmental Sciences, Directorate of Natural Resource Management, Tamil Nadu Agricultural University, Coimbatore, 641 003, Tamil Nadu, India
- School of Water, Energy, and Environment, Cranfield University, Cranfield, MK43 0AL, UK
| | - Venkatesan Veeramani
- Department of Civil Engineering, University College of Engineering, Anna University, Ariyalur, 621 731, Tamil Nadu, India
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Changotra R, Rajput H, Liu B, Murray G, He QS. Occurrence, fate, and potential impacts of wood preservatives in the environment: Challenges and environmentally friendly solutions. CHEMOSPHERE 2024; 352:141291. [PMID: 38280646 DOI: 10.1016/j.chemosphere.2024.141291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Revised: 01/08/2024] [Accepted: 01/22/2024] [Indexed: 01/29/2024]
Abstract
Wood preservation has gained global prevalence in recent years, primarily owing to the renewable nature of wood and its capacity to act as a carbon sink. Wood, in its natural form, lacks intrinsic resilience and is prone to decay if left untreated; hence, wood preservatives (WPs) are used to improve wood's longevity. The fate and potential hazards of wood preservatives to human health, ecosystems, and the environment are complex and depend on various aspects, including the type of the preservative compounds, their physicochemical properties, application methods, exposure pathways, environmental conditions, and safety measures and guidelines. The occurrence and distribution of WPs in environmental matrices such as soil and water can result in hazardous pollutants seeping into surface water, groundwater, and soil, posing health hazards, and polluting the environment. Bioremediation is crucial to safeguarding the environment and effectively removing contaminants through hydrolytic and/or photochemical reactions. Phytoremediation, vermicomposting, and sustainable adsorption have demonstrated significant efficacy in the remediation of WPs in the natural environment. Adsorbents derived from biomass waste have been acknowledged for their ability to effectively remove WPs, while also offering cost-efficiency and environmental sustainability. This paper aims to identify wood preservatives' sources and fate in the environment and present a comprehensive overview of the latest advancements in environmentally friendly methods relevant to the removal of the commonly observed contaminants associated with WPs in environmental matrices.
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Affiliation(s)
- Rahil Changotra
- Department of Engineering, Faculty of Agriculture, Dalhousie University, Truro, NS B2N 5E3, Canada
| | - Himadri Rajput
- Department of Engineering, Faculty of Agriculture, Dalhousie University, Truro, NS B2N 5E3, Canada
| | - Baoshu Liu
- School of Chemical and Pharmaceutical Engineering, Hebei University of Science and Technology, China
| | - Gordon Murray
- Stella-Jones Inc. Truro, Nova Scotia, B2N 5C1, Canada
| | - Quan Sophia He
- Department of Engineering, Faculty of Agriculture, Dalhousie University, Truro, NS B2N 5E3, Canada.
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Zhang H, Ji Z, Chen W, Pei Y. Codisposal of landfill leachate concentrate and antimony mine soils using a one-part geopolymer system for cationic and anionic heavy metals immobilization. JOURNAL OF HAZARDOUS MATERIALS 2024; 464:132909. [PMID: 37979425 DOI: 10.1016/j.jhazmat.2023.132909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 10/04/2023] [Accepted: 10/30/2023] [Indexed: 11/20/2023]
Abstract
Geopolymer solidification/stabilization technology has developed rapidly in the remediation field of heavy metal-contaminated soil. However, geopolymers exhibit low anionic heavy metal immobilization efficiency due to their electronegativity and alkali activation characteristics. This study constructed a one-part blast furnace slag-based geopolymer system using landfill leachate concentrate (LLC) as chlorine and humic acid sources and achieved the solidification/stabilization of cations (Cd, Cu, Hg, and Pb) and anions (Sb and As) in the antimony mine soils (AMS). The LLC addition increased the Sb and As fixation rates from 92%∼94% and 82∼86%, respectively, to over 99%, reducing the leaching concentration of all heavy metal ions to the ppb level. LLC improved the chemical stability and physical encapsulation of Sb/As in three ways: inducing a Friedel's salt (FS) formation, enhancing humic acid complexation/chelation, and promoting geopolymerization. Wet curing was more conducive to FS formation in the geopolymer than dry curing and increased the 28-day compressive strength by 38.5%. Due to the SiO2 skeleton support effect in AMS, a 30 wt% AMS addition was beneficial for geopolymer strength development. Our study provided a harmless method for the codisposal of LLC and AMS and improved the efficiency of geopolymer fixation of complex heavy metal cations and anions.
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Affiliation(s)
- Hao Zhang
- State Key Laboratory of Water Environment Simulation, Ministry of Education, School of Environment, Beijing Normal University, Beijing 100875, PR China; The Key Laboratory of Water and Sediment Sciences, Ministry of Education, School of Environment, Beijing Normal University, Beijing 100875, PR China
| | - Zehua Ji
- Research Center for Water Quality and Ecology, Tsinghua University, Beijing 100084, PR China
| | - Weitong Chen
- State Key Laboratory of Water Environment Simulation, Ministry of Education, School of Environment, Beijing Normal University, Beijing 100875, PR China; The Key Laboratory of Water and Sediment Sciences, Ministry of Education, School of Environment, Beijing Normal University, Beijing 100875, PR China
| | - Yuansheng Pei
- State Key Laboratory of Water Environment Simulation, Ministry of Education, School of Environment, Beijing Normal University, Beijing 100875, PR China; The Key Laboratory of Water and Sediment Sciences, Ministry of Education, School of Environment, Beijing Normal University, Beijing 100875, PR China.
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Wang YL, Tsou MCM, Lai LC, Hseu ZY, Hsi HC, Chien LC. Oral and inhalation bioaccessibility of mercury in contaminated soils and potential health risk to the kidneys and neurodevelopment of children in Taiwan. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2023; 45:6267-6286. [PMID: 37289259 DOI: 10.1007/s10653-023-01633-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 05/25/2023] [Indexed: 06/09/2023]
Abstract
Health risk assessments of exposure to mercury (Hg) from soils via ingestion and inhalation are indispensable for Taiwanese people living in the vicinity of Hg-contaminated sites. In this study, anthropogenic soils were collected from various polluted sources in Taiwan. In vitro oral and inhalation bioaccessible fractions of Hg were analyzed to avoid from overestimating the exposure risk. Discrepancies in oral and inhalation bioaccessible levels of Hg in soils were found using different in vitro assays with different pH levels and chemical compositions. The freshly contaminated soil (soil S7) polluted by chlor-alkali production activity sampled before the site was remediated had the highest total Hg concentration of 1346 mg/kg, with the highest oral bioaccessibility of 26.2% as analyzed by SW-846 Method 1340 and inhalation bioaccessibility of 30.5% as analyzed by modified Gamble's solution. The lesser extent of aging of Hg in soil S7 increased the Hg availability for humans, which was also found based on results of a sequential extraction procedure. Results of the hazard quotient showed that soil ingestion was the main pathway causing non-carcinogenic risks for children and adults. Children were also exposed to higher risks than were adults due to higher frequencies of hand-to-mouth behaviors and lower body weights. Furthermore, hazard index results adjusted for oral and inhalation bioaccessible Hg were lower than those obtained based on the total Hg content; however, an unacceptable value of the non-carcinogenic risk (> 1) for children living near soil S7 was still observed. This study suggests that children living near sites polluted for a short period of time may suffer potential renal effects regardless of the bioaccessibility. Our findings provide suggestions for decision makers on setting new strategies for managing risks of Hg-contaminated soils in Taiwan.
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Affiliation(s)
- Ying-Lin Wang
- School of Public Health, Taipei Medical University, 250 Wuxing St., Xinyi Dist., Taipei, 11031, Taiwan
- Graduate Institute of Environmental Engineering, National Taiwan University, 1 Roosevelt Rd., Sec. 4, Da'an Dist., Taipei, 10617, Taiwan
| | | | - Li-Chi Lai
- Graduate Institute of Environmental Engineering, National Taiwan University, 1 Roosevelt Rd., Sec. 4, Da'an Dist., Taipei, 10617, Taiwan
| | - Zeng-Yei Hseu
- Department of Agricultural Chemistry, National Taiwan University, Taipei, Taiwan
| | - Hsing-Cheng Hsi
- Graduate Institute of Environmental Engineering, National Taiwan University, 1 Roosevelt Rd., Sec. 4, Da'an Dist., Taipei, 10617, Taiwan.
| | - Ling-Chu Chien
- School of Public Health, Taipei Medical University, 250 Wuxing St., Xinyi Dist., Taipei, 11031, Taiwan.
- Nutrition Research Center, Taipei Medical University Hospital, Taipei, Taiwan.
- Neuroscience Research Center, Taipei Medical University, Taipei, Taiwan.
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Davis RJ, Liljestrand HM, Katz LE. Evidence for multiple removal pathways in low-temperature (200-400 °C) thermal treatment of pentachlorophenol-laden soils. JOURNAL OF HAZARDOUS MATERIALS 2020; 400:122870. [PMID: 32947725 DOI: 10.1016/j.jhazmat.2020.122870] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 04/28/2020] [Accepted: 04/29/2020] [Indexed: 06/11/2023]
Abstract
Polychlorinated aromatic compounds (PCACs) pose significant remediation challenges, since their high soil affinities preclude mobile-phase partitioning and subsurface extraction. To enhance partitioning and desorption, subsurface temperatures are raised using a technique called thermal conduction heating-soil vapor extraction (TCH-SVE). While this technique improves PCAC partitioning, it can also promote several degradation reactions under temperatures typical of low-temperature TCH-SVE (200-400 °C). While these reactions are labile, the extent to which they occur in flow-through TCH-SVE is unclear. The current research used bench-scale, flow-through TCH-SVE to assess relative importance of three removal pathways: (1) target volatilization, (2) reductive dechlorination, and (3) oxidation via OH-addition. Pentachlorophenol was used as a representative PCAC, and pathway contributions, extents, and regioselectivity were examined as a function of temperature (225-375 °C) and gas-phase oxygen content (air vs. nitrogen). Across treatments, OH-addition and dechlorination occurred in parallel and accounted for significantly more removal than PCP volatilization. OH-addition byproducts had highest yields (regardless of oxygen content) and were consistent with surface-mediated OH production and ring addition. OH-addition increased with temperature while volatilization and dechlorination decreased. Notable exceptions occurred between 225 and 325 °C (where dechlorination dropped 10-fold) and 325 and 375 °C (where OH-addition fell 75%), signifying major mechanism shifts in these intervals.
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Affiliation(s)
- R Justin Davis
- Center for Water and the Environment, The University of Texas at Austin, Austin, TX, USA.
| | - Howard M Liljestrand
- Center for Water and the Environment, The University of Texas at Austin, Austin, TX, USA.
| | - Lynn E Katz
- Center for Water and the Environment, The University of Texas at Austin, Austin, TX, USA.
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Urbaniak M, Baran A, Lee S, Kannan K. Utilization of PCB-contaminated Hudson River sediment by thermal processing and phytoremediation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 738:139841. [PMID: 32526423 DOI: 10.1016/j.scitotenv.2020.139841] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Revised: 05/26/2020] [Accepted: 05/28/2020] [Indexed: 05/23/2023]
Abstract
The need to dispose of dredged sediments and development of appropriate technology for their safe utilization has become a growing problem in recent years. It has been proposed that dredged, fresh sediments can be utilized in agriculture or environment; however there is also growing interest in the use of thermally-treated sediments. Hence, the aim of this study was threefold: 1) to evaluate the effect of two incineration temperatures (300 °C and 600 °C) on the chemical and ecotoxicological properties of sediment; 2) select the appropriate treatment for further phytoremediation experiments with zucchini; and 3) assess the impact of sediment admixture on the physico-chemical parameters of soil, based on the responses of Aliivibrio fischeri and growth of zucchini (Cucurbita pepo L. cv 'Black Beauty'). A range of chemical (inductively-coupled plasma optical emission spectrophotometry for macro- and trace elements; gas chromatography for polychlorinated biphenyls (PCBs)), ecotoxicological (Microtox assay), and plant morphology (biomass measurement) as well as physiological analyses (spectrophotometry for chlorophyll) were applied. River sediments incinerated at 600 °C resulted in better chemical and ecotoxicological properties than incinerated at 300 °C or no incinerated. Incineration at 600 °C removed PCBs from sediment. In culture experiments conducted with zucchini, sediment treated at 300 °C demonstrated a 51-81% reduction in PCB concentrations compared to untreated sediment. After four weeks of growth, the raw sediment showed a significant increase in K, Fe, Cr, Pb, Zn concentrations, whereas the thermally-processed sediment showed a decrease in Ca, Na, P, Cd, Cu, Ni, and Zn concentrations. Both the fresh and thermally-treated sediment types influenced plant growth positively: they demonstrated higher biomass production than plants grown in control soil; however, plants grown on soil with thermally-processed sediment demonstrated lower biomass than those grown in raw sediment. Chlorophyll content was affected negatively by admixtures of soil with treated or untreated sediment, while a lower chlorophyll a/b ratio was observed in plants grown on an admixture of thermally-treated sediment with soil. Our findings suggest that the use of sediments as a growth medium component may be a promising way for their utilization and transformation from waste material to a valuable resource enhancing the benefits to the environment.
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Affiliation(s)
- Magdalena Urbaniak
- Wadsworth Center, New York State Department of Health, Empire State Plaza, P.O. Box 509, Albany, NY 12201-0509, USA; UNESCO Chair of Ecohydrology and Applied Ecology, Faculty of Biology and Environmental Protection, University of Lodz, Banacha 12/16, 90-237 Lodz, Poland.
| | - Agnieszka Baran
- University of Agriculture in Krakow, Faculty of Agriculture and Economics, Department of Agricultural and Environmental Chemistry, Al. Mickiewicza 21, 31-120 Krakow, Poland
| | - Sunmi Lee
- Wadsworth Center, New York State Department of Health, Empire State Plaza, P.O. Box 509, Albany, NY 12201-0509, USA
| | - Kurunthachalam Kannan
- Wadsworth Center, New York State Department of Health, Empire State Plaza, P.O. Box 509, Albany, NY 12201-0509, USA; Department of Pediatrics and Department of Environmental Medicine, New York University School of Medicine, New York, NY 10016, USA
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Kaewlaoyoong A, Cheng CY, Lin C, Chen JR, Huang WY, Sriprom P. White rot fungus Pleurotus pulmonarius enhanced bioremediation of highly PCDD/F-contaminated field soil via solid state fermentation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 738:139670. [PMID: 32534283 DOI: 10.1016/j.scitotenv.2020.139670] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 05/20/2020] [Accepted: 05/22/2020] [Indexed: 06/11/2023]
Abstract
This study was performed to evaluate the use of white rot fungus, Pleurotus pulmonarius, to treat polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) in contaminated soil using solid state fermentation (SSF). The soil was collected from a long-closed pentachlorophenol plant in southern Taiwan. The non-sterilized soil with a total PCDD/F concentration of 14,000 ± 2400 ng I-TEQ kg-1 was mixed directly with the solid fungal inocula at dry w/w ratio of 1:1.4 (ratio-adjusted test) and incubated at 26 ± 2 °C in a controlled environment. The highest PCDD/F decomposition was observed during the mycelium colonization. Pearson correlation coefficient (r) studied during this period (35 days) indicated that laccase had no significant correlation (r = -0.53), while manganese peroxidase had a strong positive correlation (r = 0.88) with PCDD/F decomposition efficiency. After 72 days, the more toxic congeners, tetra- and penta-CDD/Fs were removed to non-detectable levels. Meanwhile, the removal efficiencies of hexa-, hepta-, and octa-CDD/Fs were >80%, >97%, and >90%, respectively. The simultaneous degradation of low and high chlorinated DD/Fs suggested that overall removal was nonspecific. The overall PCDD/F removal was 96%, and the residual concentration (276 ng I-TEQ kg-1) was below the regulatory control limit (1000 ng I-TEQ kg-1). In conclusion, this study shows that P. pulmonarius via SSF can successfully remediate the PCDD/F-contaminated field soil. Furthermore, this SSF technique overcame the well-known intractability of PCDD/F biodegradation in non-sterilized soil, making it promising for actual field application.
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Affiliation(s)
- Acharee Kaewlaoyoong
- Department of Safety, Health, and Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 82445, Taiwan
| | - Chih-Yu Cheng
- Department of Marine Biotechnology, National Kaohsiung University of Science and Technology, Kaohsiung 81157, Taiwan
| | - Chitsan Lin
- Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 81157, Taiwan.
| | - Jenq-Renn Chen
- Department of Safety, Health, and Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 82445, Taiwan
| | - Wen-Yen Huang
- Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 81157, Taiwan
| | - Pongsert Sriprom
- Program of Food Process Engineering, Faculty of Agro-Industry, King Mongkut's Institute of Technology Ladkrabang, Bangkok 10520, Thailand
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Chang LS, Yan JH, Li JY, Yeter DD, Huang YH, Guo MMH, Lo MH, Kuo HC. Blood Mercury Levels in Children with Kawasaki Disease and Disease Outcome. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17103726. [PMID: 32466179 PMCID: PMC7277186 DOI: 10.3390/ijerph17103726] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 05/20/2020] [Accepted: 05/22/2020] [Indexed: 12/13/2022]
Abstract
The risk of ethnic Kawasaki disease (KD) has been proposed to be associated with blood mercury levels in American children. We investigated the blood levels of mercury in children with KD and their association with disease outcome. The mercury levels demonstrated a significantly negative correlation with sodium levels (p = 0.007). However, data failed to reach a significant difference after excluding the child with blood mercury exceeding the toxic value. The findings indicate that KD patients with lower sodium concentrations had a remarkably higher proportion of intravenous immunoglobulin (IVIG) resistance (p = 0.022). Our patients who had lower mercury levels (<0.5 μg/L) had more changes in bacille Calmette-Guerin. Mercury levels in 14/14 patients with coronary artery lesions and 4/4 patients with IVIG resistance were all measured to have values greater than 1 μg/L (while average values showed 0.92 μg/L in Asian American children). Mercury levels had no correlations with IVIG resistance or coronary artery lesion (CAL) formation (p > 0.05). CAL development was more common in the incomplete group than in the complete KD group (p = 0.019). In this first report about mercury levels in KD patients, we observed that the juvenile Taiwanese had higher mercury concentration in blood compared to other populations.
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Affiliation(s)
- Ling-Sai Chang
- Department of Pediatrics and Kawasaki Disease Center, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan; (L.-S.C.); (Y.-H.H.); (M.M.-H.G.); (M.-H.L.)
| | - Jia-Huei Yan
- Department of Pediatrics, Chiayi Chang Gung Memorial Hospital, Chiayi 613016, Taiwan;
| | - Jin-Yu Li
- Beijing Institute of Technology, School of Life Science, Beijing 100081, China;
| | - Deniz Des Yeter
- KU School of Nursing, Nursing Associate Tech Adult Inpatient Psych KU Strawberry Hill Campus, Kansas City, KS 66101, USA;
| | - Ying-Hsien Huang
- Department of Pediatrics and Kawasaki Disease Center, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan; (L.-S.C.); (Y.-H.H.); (M.M.-H.G.); (M.-H.L.)
| | - Mindy Ming-Huey Guo
- Department of Pediatrics and Kawasaki Disease Center, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan; (L.-S.C.); (Y.-H.H.); (M.M.-H.G.); (M.-H.L.)
- Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Kaohsiung 83301, Taiwan
| | - Mao-Hung Lo
- Department of Pediatrics and Kawasaki Disease Center, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan; (L.-S.C.); (Y.-H.H.); (M.M.-H.G.); (M.-H.L.)
| | - Ho-Chang Kuo
- Department of Pediatrics and Kawasaki Disease Center, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan; (L.-S.C.); (Y.-H.H.); (M.M.-H.G.); (M.-H.L.)
- Department of Respiratory Therapy, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung City 83301, Taiwan
- Correspondence:
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Souza LRR, Pomarolli LC, da Veiga MAMS. From classic methodologies to application of nanomaterials for soil remediation: an integrated view of methods for decontamination of toxic metal(oid)s. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:10205-10227. [PMID: 32064582 DOI: 10.1007/s11356-020-08032-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 02/10/2020] [Indexed: 06/10/2023]
Abstract
Soil pollution with toxic elements is a recurrent issue due to environmental disasters, fossil fuel burning, urbanization, and industrialization, which have contributed to soil contamination over the years. Therefore, the remediation of toxic metals in soil is always an important topic since contaminated soil can affect the environment, agricultural safety, and human health. Many remediation methods have been developed; however, it is essential to ensure that they are safe, and also take into account the limitation of each methodology (including high energy input and generation of residues). This scenario has motivated this review, where we explore soil contamination with arsenic, lead, mercury, and chromium and summarize information about the methods employed to remediate each of these toxic elements such as phytoremediation, soil washing, electrokinetic remediation, and nanoparticles besides elucidating some mechanisms involved in the remediation. Considering all the discussed techniques, nowadays, different techniques can be combined together in order to improve the efficiency of remediation besides the new approach of the techniques and the use of one technique for remediating more than one contaminant.
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Wang L, Hou D, Cao Y, Ok YS, Tack FMG, Rinklebe J, O'Connor D. Remediation of mercury contaminated soil, water, and air: A review of emerging materials and innovative technologies. ENVIRONMENT INTERNATIONAL 2020; 134:105281. [PMID: 31726360 DOI: 10.1016/j.envint.2019.105281] [Citation(s) in RCA: 150] [Impact Index Per Article: 37.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 09/23/2019] [Accepted: 10/20/2019] [Indexed: 05/24/2023]
Abstract
Mercury contamination in soil, water and air is associated with potential toxicity to humans and ecosystems. Industrial activities such as coal combustion have led to increased mercury (Hg) concentrations in different environmental media. This review critically evaluates recent developments in technological approaches for the remediation of Hg contaminated soil, water and air, with a focus on emerging materials and innovative technologies. Extensive research on various nanomaterials, such as carbon nanotubes (CNTs), nanosheets and magnetic nanocomposites, for mercury removal are investigated. This paper also examines other emerging materials and their characteristics, including graphene, biochar, metal organic frameworks (MOFs), covalent organic frameworks (COFs), layered double hydroxides (LDHs) as well as other materials such as clay minerals and manganese oxides. Based on approaches including adsorption/desorption, oxidation/reduction and stabilization/containment, the performances of innovative technologies with the aid of these materials were examined. In addition, technologies involving organisms, such as phytoremediation, algae-based mercury removal, microbial reduction and constructed wetlands, were also reviewed, and the role of organisms, especially microorganisms, in these techniques are illustrated.
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Affiliation(s)
- Liuwei Wang
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Deyi Hou
- School of Environment, Tsinghua University, Beijing 100084, China.
| | - Yining Cao
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Yong Sik Ok
- Korea Biochar Research Center & Division of Environmental Science and Ecological Engineering, Korea University, Seoul 02841, Republic of Korea
| | - Filip M G Tack
- Department of Green Chemistry and Technology, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
| | - Jörg Rinklebe
- University of Wuppertal, School of Architecture and Civil Engineering, Institute of Foundation Engineering, Water- and Waste-Management, Laboratory of Soil- and Groundwater-Management, Pauluskirchstraße 7, Wuppertal 42285, Germany; Department of Environment, Energy and Geoinformatics, Sejong University, 98 Gunja-Dong, Seoul, Republic of Korea
| | - David O'Connor
- School of Environment, Tsinghua University, Beijing 100084, China
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Ma F, Zhu Y, Wu B, Zhang Q, Xu D, Xu J, Wang B, Gu Q, Li F. Degradation of DDTs in thermal desorption off-gas by pulsed corona discharge plasma. CHEMOSPHERE 2019; 233:913-919. [PMID: 31340419 DOI: 10.1016/j.chemosphere.2019.05.292] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 05/26/2019] [Accepted: 05/31/2019] [Indexed: 06/10/2023]
Abstract
Thermal desorption has been widely employed to treat soils contaminated with chlorinated organics. The off-gas of thermal desorption must be treated to avoid secondary pollution. In this study, the treatment of DDTs in thermal desorption off-gas by pulsed corona discharge plasma was investigated. The effects of important operation parameters, including energy density, gas temperature, humidity, and O2 content, on DDTs degradation were investigated. The main degradation products were also studied. The DDTs degradation efficiency increased with the increase in energy density, gas temperature, and O2 content. The degradation efficiency of DDTs was achieved to 84.6% when the initial concentration, energy density, and gas flow rate were 2.0 mg/m3, 17.8 J/L, and 3.0 L/min, respectively. Maximum DDTs degradation efficiency was observed when the gas was at 5% relative humidity. The main degradation products identified were DM, phenol, benzene, acetic acid, and formic acid. It was calculated that 87% of chlorine in the degraded DDTs was converted into chloride ion.
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Affiliation(s)
- Fujun Ma
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Yina Zhu
- School of Chemical and Environmental Engineering, China University of Mining and Technology, Beijing, 100083, China
| | - Bin Wu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Qian Zhang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Dongyao Xu
- School of Chemical and Environmental Engineering, China University of Mining and Technology, Beijing, 100083, China
| | - Jingwen Xu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Bin Wang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Qingbao Gu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.
| | - Fasheng Li
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
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12
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Le LTH, Dat ND, Minh NH, Nguyen KA. Characteristics of PCDD/Fs in soil and sediment samples collected from A-So former airbase in Central Vietnam. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 661:27-34. [PMID: 30665129 DOI: 10.1016/j.scitotenv.2019.01.163] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 01/13/2019] [Accepted: 01/13/2019] [Indexed: 06/09/2023]
Abstract
A-So airbase, located in A-Luoi Valley - Central Vietnam, is a former military base occupied by US Special Forces between 1963 and 1966. The storage of Agent Orange in A-So airbase during the Vietnam War now poses a high potential for PCDD/F contamination in soils and sediments. In order to evaluate the occurrence and characteristics of PCDD/Fs in A-So former airbase, which has been reserved for a long time and suffered almost no significant anthropogenic impacts, soil and sediment samples were collected from 40 sites of two adjacent zones A and B in an area of 160,000 m2. Seventeen 2,3,7,8-substituted PCDD/Fs were analyzed using HRCG/HRMS (US EPA method 1613). Results indicate that concentrations of PCDD/Fs measured in zone A ranged from 95.0 to 4534 ng kgdw-1 (4.58 to 746 ng TEQ kgdw-1), while those in zone B were in the range of 80.8-4150 ng kgdw-1 (2.70-89.0 ng TEQ kgdw-1). The concentrations of PCDD/Fs observed in zone A are higher than those in zone B, suggesting that PCDD/Fs could be transported from zone A to zone B through surface soil erosion and runoff events. The main contributor to the total TEQ concentration was 2,3,7,8-TCDD, which was the indicator of Agent Orange contamination, accounting for 91 ± 9% and 72 ± 17% of the total TEQ concentrations measured in zones A and B, respectively. Comparison of PCDD/F concentrations in different soil layers reveals that the topsoil layer (at depth < 1 m) contributed 81-95% to the total PCDD/Fs in the study area, indicating that future remediation projects should focus on this topsoil layer. Since PCDD/F contamination in A-So airbase has not significantly improved for the last 20 years, remediation projects are urgently needed in order to mitigate the negative impacts of PCDD/F contamination on human health and wellbeing.
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Affiliation(s)
- Le Thi Hai Le
- Hanoi University of Natural Resources and Environment, Phu Dien, North-Tu Liem, Hanoi 10000, Viet Nam.
| | - Nguyen Duy Dat
- Graduate Institute of Environmental Engineering, National Central University (NCU), Zhongli, Taoyuan 32001, Taiwan, ROC; Faculty of Chemical & Food Technology, Ho Chi Minh City University of Technology and Education, Thu Duc, Ho Chi Minh 700000, Viet Nam.
| | - Nguyen Hung Minh
- Vietnam Environment Administration, Nguyen Van Cu, Long Bien District, Hanoi 10000, Viet Nam
| | - Kim-Anh Nguyen
- Center for Space and Remote Sensing Research, National Central University (NCU), Zhongli, Taoyuan 32001, Taiwan, ROC; Institute of Geography, Vietnam Academy of Science and Technology, 18-Hoang Quoc Viet, Hanoi 10000, Viet Nam
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13
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Bai N, Wang W, Zhao Y, Feng W, Li P. Theoretical Insights into the Reaction Mechanism between 2,3,7,8-Tetrachlorodibenzofuran and Hydrogen Peroxide: A DFT Study. ACS OMEGA 2019; 4:358-367. [PMID: 31459335 PMCID: PMC6648065 DOI: 10.1021/acsomega.8b00724] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Accepted: 07/19/2018] [Indexed: 06/10/2023]
Abstract
A detailed knowledge of the reactivity of 2,3,7,8-tetrachlorodibenzofuran (TCDF) at the molecular level is important to better understand the transformation of dioxins analogous to TCDF in the environment. To clarify the reactivity of the organic hydroperoxides toward TCDF, the reaction of the TCDF with hydrogen peroxide (H2O2) and its anion has been investigated theoretically. For the reaction of the neutral H2O2, a molecular complex can be formed between TCDF and H2O2 first. Then, the nucleophilic aromatic substitution of TCDF by H2O2 occurs in the presence of the water molecules to form an intermediate containing an O-O bond. Finally, the O-O bond cleavages homolytically for the above intermediate. On the other hand, as for the reaction of the anion of H2O2 (HO2 -), the nucleophilic addition of HO2 - to TCDF can also occur besides the nucleophilic aromatic substitution reaction mentioned above, resulting in the dissociation of the C-O bond of TCDF. Unlike the reaction involving neutral H2O2, no water molecules are required. In addition, the selected substitution effects, such as F-, Br-, and CH3-substituents, on the reactivity of the above reaction have also been explored. Hopefully, the present results can enable us to gain insights into the reactivity of the organic hydroperoxides with TCDF-like environmental pollutants.
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Affiliation(s)
- Nana Bai
- Key Laboratory of Life-Organic
Analysis, School of Chemistry and Chemical Engineering, Qufu Normal University, No. 57 Jingxuan West Road, Qufu 273165, P. R. China
| | - Weihua Wang
- Key Laboratory of Life-Organic
Analysis, School of Chemistry and Chemical Engineering, Qufu Normal University, No. 57 Jingxuan West Road, Qufu 273165, P. R. China
| | - Yun Zhao
- Key Laboratory of Life-Organic
Analysis, School of Chemistry and Chemical Engineering, Qufu Normal University, No. 57 Jingxuan West Road, Qufu 273165, P. R. China
| | - Wenling Feng
- Key Laboratory of Life-Organic
Analysis, School of Chemistry and Chemical Engineering, Qufu Normal University, No. 57 Jingxuan West Road, Qufu 273165, P. R. China
| | - Ping Li
- Key Laboratory of Life-Organic
Analysis, School of Chemistry and Chemical Engineering, Qufu Normal University, No. 57 Jingxuan West Road, Qufu 273165, P. R. China
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14
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Wang W, Wang Y, Feng W, Wang W, Li P. Theoretical Investigations on the Reactivity of Hydrogen Peroxide toward 2,3,7,8-Tetrachlorodibenzo- p-dioxin. Molecules 2018; 23:E2826. [PMID: 30384440 PMCID: PMC6278397 DOI: 10.3390/molecules23112826] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2018] [Revised: 10/26/2018] [Accepted: 10/27/2018] [Indexed: 11/16/2022] Open
Abstract
Acquiring full knowledge of the reactivity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is crucial for the better understanding of the transformation and degradation of TCDD-like dioxins in the environment. To clarify the reactivity of the organic hydroperoxides toward TCDD, in this study, the reactions between the neutral/anion of the hydrogen peroxide (H₂O₂) and TCDD have been systematically investigated theoretically. It was found that the neutral H₂O₂ is relatively difficult to react with TCDD compared with its anion, exhibiting the pH dependence of the title reaction. As for the anion of H₂O₂, it reacts with TCDD through two reaction mechanisms, i.e., nucleophilic substitution and nucleophilic addition. For the former, the terminal O atom of HO₂- nucleophilically attacks the C atom of the C-Cl bond in TCDD to form an intermediate containing an O-O bond, accompanying the dissociation of the chlorine atom. For the latter, the terminal O atom of HO₂- can be easily attached to the C atom of the C-O bond in TCDD, resulting in the decomposition of C-O bond and the formation of an intermediate containing an O-O bond. For these formed intermediates in both reaction mechanisms, their O-O bonds can be homolytically cleaved to produce different radicals. In addition, the selected substitution effects including F-, Br-, and CH₃- substituents on the above reactions have also been studied. Hopefully, the present results can provide new insights into the reactivity of the organic hydroperoxides toward TCDD-like environmental pollutants.
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Affiliation(s)
- Weihua Wang
- Key Laboratory of Life-Organic Analysis, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, China.
| | - Yuhua Wang
- Key Laboratory of Life-Organic Analysis, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, China.
| | - Wenling Feng
- Key Laboratory of Life-Organic Analysis, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, China.
| | - Wenliang Wang
- Key Laboratory of Life-Organic Analysis, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, China.
| | - Ping Li
- Key Laboratory of Life-Organic Analysis, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, China.
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15
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Wang W, Feng W, Wang W, Li P. Theoretical Investigations on the Reactivity of Methylidyne Radical toward 2,3,7,8-Tetrachlorodibenzo- p-Dioxin: A DFT and Molecular Dynamics Study. Molecules 2018; 23:E2685. [PMID: 30340385 PMCID: PMC6222546 DOI: 10.3390/molecules23102685] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 10/15/2018] [Accepted: 10/16/2018] [Indexed: 12/22/2022] Open
Abstract
To explore the potential reactivity of the methylidyne radical (CH) toward 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), the reaction mechanism between them has been systematically investigated employing the density functional theory (DFT) and ab initio molecular dynamics simulations. The relevant thermodynamic and kinetic parameters in the possible reaction pathways have been discussed as well as the IR spectra and hyperfine coupling constants (hfcc's) of the major products. Different from the reaction of the CH radical with 2,3,7,8-tetrachlorodibenzofuran, CH radical can attack all the C-C bonds of TCDD to form an initial intermediate barrierlessly via the cycloaddition mechanism. After then, the introduced C-H bond can be further inserted into the C-C bond of TCDD, resulting in the formation of a seven-membered ring structure. The whole reactions are favorable thermodynamically and kinetically. Moreover, the major products have been verified by ab initio molecular dynamics simulations. The distinct IR spectra and hyperfine coupling constants of the major products can provide some help for their experimental detection and identification. In addition, the reactivity of the CH radical toward the F- and Br-substituted TCDDs has also been investigated. Hopefully, the present findings can provide new insights into the reactivity of the CH radical in the transformation of TCDD-like dioxins.
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Affiliation(s)
- Weihua Wang
- Key Laboratory of Life-Organic Analysis, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, China.
| | - Wenling Feng
- Key Laboratory of Life-Organic Analysis, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, China.
| | - Wenliang Wang
- Key Laboratory of Life-Organic Analysis, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, China.
| | - Ping Li
- Key Laboratory of Life-Organic Analysis, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, China.
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16
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Rathna R, Varjani S, Nakkeeran E. Recent developments and prospects of dioxins and furans remediation. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2018; 223:797-806. [PMID: 29986327 DOI: 10.1016/j.jenvman.2018.06.095] [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: 04/08/2018] [Revised: 06/10/2018] [Accepted: 06/30/2018] [Indexed: 05/18/2023]
Abstract
Rapid urbanization and industrialization of anthropogenic activities have exerted immense pressure on the environment. Polyhalogenated organic compounds, especially dioxins and furans are regarded as ubiquitously persistent environmental pollutants in the ecosystem. The recalcitrant nature of dioxins and furans induce toxicity in both humans and wildlife. Dioxins and furans are generated by defective technological chemical processes that occur during the manufacture of herbicides and pesticides, use of fertilizers, bleaching of paper and wood pulp and incomplete combustion process. However, incineration and incomplete combustion of solid waste are the main cause for the discharge of dioxins and furans to the environment. During incineration and incomplete combustion, noxious flue gas and ashes are released into the atmosphere and contaminate the soil and water systems; thereby affecting the ecology. According to World Health Organization fact sheet 2016, more than 90% of human exposure to dioxins is through the food chain, especially from dairy products, seafood and meat. These pollutants are mutagenic, carcinogenic, immunotoxic and teratogenic for lower and higher forms of life i.e. microorganisms to humans. This review describes the sources of dioxins and furans pollution, hazardous effects on the ecosystem and recent techniques to minimize and treat dioxins and furans contaminants in the environment. This paper also previews the significance of conventional and latest remediation techniques prevailing around the globe for treating dioxins and furans entry into the ecosystem.
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Affiliation(s)
- Ravichandran Rathna
- Research Laboratory, Department of Biotechnology, Sri Venkateswara College of Engineering (Autonomous), Sriperumbudur Tk, 602 117, Tamil Nadu, India
| | - Sunita Varjani
- Gujarat Pollution Control Board, Sector-10A, Gandhinagar, 382 010, Gujarat, India
| | - Ekambaram Nakkeeran
- Research Laboratory, Department of Biotechnology, Sri Venkateswara College of Engineering (Autonomous), Sriperumbudur Tk, 602 117, Tamil Nadu, India.
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17
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Chang MB, Hsu YC, Chang SH. Removal of PCDD/Fs, PCP and mercury from sediments: Thermal oxidation versus pyrolysis. CHEMOSPHERE 2018; 207:10-17. [PMID: 29763762 DOI: 10.1016/j.chemosphere.2018.05.037] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 03/30/2018] [Accepted: 05/06/2018] [Indexed: 06/08/2023]
Abstract
A continuous pilot-scale system (CPS) equipped with effective air pollution control devices (APCDs) is used for remediating the sediments contaminated with PCDD/Fs, PCP and Hg simultaneously. The removal efficiencies of these three pollutants in sediments collected from seawater pond and river, respectively, are evaluated via thermal treatment processes. PAHs and CBz formed during thermal oxidation and pyrolysis are also analyzed for better understanding the behaviors of chlorinated organic compounds. Experimental results indicate that low-molecular-weight PAHs are closely related to the formation of CBz, PCDD/Fs, and CPs, while low chlorinated PCDD/Fs and CBz are predominant in flue gas with thermal oxidation. However, the PM concentration is higher in thermal oxidation than pyrolysis due to the higher air flow rate of thermal oxidation. It may bring more particles out of the furnace and have a greater potential to form PCDD/Fs within APCDs. Besides, the high air flow also dilutes the Hg vapor in flue gas and would require more energy to condense and collect Hg with the quench tower. Furthermore, for removal of total amount of PCDD/Fs, pyrolysis is better than thermal oxidation. Thus, pyrolysis is more suitable for remediating the contaminated sediment. The removal efficiencies of PCDD/Fs, PCP and Hg in sediments achieved with pyrolysis increase with increasing operating temperature and retention time in CPS. Overall, the residual concentrations of PCDD/Fs and PCP in river sediment are higher than that in seawater-pond sediment since significant formation of tar is observed due to higher organic matter content in river sediment.
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Affiliation(s)
- Moo-Been Chang
- Graduate Institute of Environmental Engineering, National Central University, Chungli, 320, Taiwan.
| | - Yen-Chen Hsu
- Graduate Institute of Environmental Engineering, National Central University, Chungli, 320, Taiwan
| | - Shu-Hao Chang
- Graduate Institute of Environmental Engineering, National Central University, Chungli, 320, Taiwan
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18
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Wei W, Wang W, Xu K, Feng W, Li X, Li P. Theoretical insights into the reaction mechanisms between 2,3,7,8-tetrachlorodibenzofuran and the methylidyne radical. RSC Adv 2018; 8:21150-21163. [PMID: 35539902 PMCID: PMC9080895 DOI: 10.1039/c8ra03046d] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 06/03/2018] [Indexed: 11/21/2022] Open
Abstract
To explore the potential role of the methylidyne radical (CH) in the transformation of 2,3,7,8-tetrachlorodibenzofuran (TCDF), in this study, the detailed reaction mechanisms between TCDF and CH radical have been systematically investigated employing the B3LYP method of density functional theory (DFT) in combination with the atoms in molecules (AIM) theory and ab initio molecular dynamics. It was found that the title reaction is a multi-channel reaction, i.e., the CH radical can attack the C-X (X = C, Cl, H, O) bonds of TCDF via the insertion modes, resulting in the formation of 13 products. Thermodynamically, the whole reaction processes are exothermic and spontaneous since all the enthalpy and Gibbs free energy changes are negative values in the formation processes. Moreover, the thermodynamic stability of the products is controlled by the distribution of the single unpaired electron. Kinetically, the most favorable reaction channel is the insertion of the CH radical into the C-C bond except for the C atoms attached to the chlorine atom. Moreover, the dominant products have been further confirmed by the molecular dynamics. Meanwhile, the IR spectra and hyperfine coupling constants of the dominant products have been investigated to provide helpful information for their identification experimentally. In addition, the reactivity of the CH radical toward the F- and Br-substituted TCDFs has also been investigated. Expectedly, the present findings can enable us to better understand the reactivity of the CH radical toward organic pollutants analogous to TCDF in the atmosphere.
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Affiliation(s)
- Wenjing Wei
- Key Laboratory of Life-Organic Analysis, School of Chemistry and Chemical Engineering, Qufu Normal University Qufu 273165 P. R. China
| | - Weihua Wang
- Key Laboratory of Life-Organic Analysis, School of Chemistry and Chemical Engineering, Qufu Normal University Qufu 273165 P. R. China
| | - Kaining Xu
- Key Laboratory of Life-Organic Analysis, School of Chemistry and Chemical Engineering, Qufu Normal University Qufu 273165 P. R. China
| | - Wenling Feng
- Key Laboratory of Life-Organic Analysis, School of Chemistry and Chemical Engineering, Qufu Normal University Qufu 273165 P. R. China
| | - Xiaoping Li
- Key Laboratory of Life-Organic Analysis, School of Chemistry and Chemical Engineering, Qufu Normal University Qufu 273165 P. R. China
| | - Ping Li
- Key Laboratory of Life-Organic Analysis, School of Chemistry and Chemical Engineering, Qufu Normal University Qufu 273165 P. R. China
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19
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Bai ST, Chang SH, Duh JM, Sung FH, Su JS, Chang MB. Characterization of PCDD/Fs and dioxin-like PCBs emitted from two woodchip boilers in Taiwan. CHEMOSPHERE 2017; 189:284-290. [PMID: 28942254 DOI: 10.1016/j.chemosphere.2017.09.080] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 09/14/2017] [Accepted: 09/17/2017] [Indexed: 06/07/2023]
Abstract
This study investigates the formation and removal of PCDD/Fs and dl-PCBs in two woodchips boilers during different operating periods. Results indicate that combustion condition affects PCDD/F and dl-PCB formation within the woodchip combustion process. PCDD/F and dl-PCB concentrations during the start-up period are much higher than those measured during normal operation and shut-down periods due to unstable combustion. PCDD/F and dl-PCB concentrations at APCDs inlet of Plant A are significantly higher than that of Plant B due to the lower combustion temperature (500-850 °C) compared with Plant B (850-925 °C). Major PCDD/F congeners at APCDs inlet of both plants during normal operation are O8CDD, 1,2,3,4,6,7,8-H7CDD and 1,2,3,4,6,7,8-H7CDF, while major dl-PCBs are TeCB-77, PeCB-118 and PeCB-126. The removal efficiencies of PCDD/F and PCBs achieved with the APCDs of Plant A are 95.6% and 88.6%, respectively, while those of Plant B are 99.3% and 94.9%. Possibly, the AC concentration of Plant A exceeds the optimal AC concentration and, PCDD/Fs and dl-PCBs might be formed because the AC injected can supply additional reaction area and carbon source. Also, this may be due to different operating temperatures of APCDs, which affects removal efficiency of PCDD/F and dl-PCB congeners. The emission factors (PCDD/Fs + dl-PCBs) of Plants A and B are calculated as 17.86 and 1.25 μg I-TEQ/ton, respectively. Concentrations of PCDD/Fs in the BF ash of Plants A and B during normal operation are measured as 98.57 and 38.06 ng I-TEQ/g, which are significantly higher than the standard limit (1.0 ng I-TEQ/g) promulgated by Taiwan EPA.
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Affiliation(s)
- Shih Ting Bai
- Graduate Institute of Environmental Engineering, National Central University, Jhongli, 32001, Taiwan, ROC
| | - Shu Hao Chang
- Graduate Institute of Environmental Engineering, National Central University, Jhongli, 32001, Taiwan, ROC
| | - Jing Min Duh
- Research Laboratories of Green Energy and Environment, Industrial Technology Research Institute, Hsinchu, 32001, Taiwan, ROC
| | - Fu Hsiang Sung
- Research Laboratories of Green Energy and Environment, Industrial Technology Research Institute, Hsinchu, 32001, Taiwan, ROC
| | - Jhen Sheng Su
- Section of Air Quality Protection, Department of Environmental Protection, Taoyuan City Government, Taoyuan, 32001, Taiwan, ROC
| | - Moo Been Chang
- Graduate Institute of Environmental Engineering, National Central University, Jhongli, 32001, Taiwan, ROC.
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20
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Guemiza K, Coudert L, Metahni S, Mercier G, Besner S, Blais JF. Treatment technologies used for the removal of As, Cr, Cu, PCP and/or PCDD/F from contaminated soil: A review. JOURNAL OF HAZARDOUS MATERIALS 2017; 333:194-214. [PMID: 28359036 DOI: 10.1016/j.jhazmat.2017.03.021] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 03/08/2017] [Accepted: 03/09/2017] [Indexed: 06/07/2023]
Abstract
The contamination of soils by metals such as arsenic, chromium, copper and organic compounds such as pentachlorophenol (PCP) and dioxins and furans (PCDD/F) is a major problem in industrialized countries. Excavation followed by disposal in an appropriate landfilling is usually used site to manage these contaminated soils. Many researches have been conducted to develop physical, biological, thermal and chemical methods to allow the rehabilitation of contaminated sites. Thermal treatments including thermal desorption seemed to be the most appropriate methods, allowing the removal of more than 99.99% of organic contaminants but, they are ineffective for inorganic compounds. Biological treatments have been developed to remove inorganic and hydrophobic organic contaminants but their applications are limited to soils contaminated by easily biodegradable organic compounds. Among the physical technologies available, attrition is the most commonly used technique for the rehabilitation of soils contaminated by both organic and inorganic contaminants. Chemical processes using acids, bases, redox agents and surfactants seemed to be an interesting option to simultaneously extract organic and inorganic contaminants from soils. This paper will provide an overview of the recent developments in the field of decontamination technologies applicable for the removal of As, Cr, Cu, PCP and/or PCDD/F from contaminated soils.
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Affiliation(s)
- Karima Guemiza
- Institut national de la recherche scientifique (Centre Eau, Terre et Environnement), Université du Québec, 490 rue de la Couronne, Québec, QC, G1 K 9A9, Canada.
| | - Lucie Coudert
- Institut national de la recherche scientifique (Centre Eau, Terre et Environnement), Université du Québec, 490 rue de la Couronne, Québec, QC, G1 K 9A9, Canada.
| | - Sabrine Metahni
- Institut national de la recherche scientifique (Centre Eau, Terre et Environnement), Université du Québec, 490 rue de la Couronne, Québec, QC, G1 K 9A9, Canada.
| | - Guy Mercier
- Institut national de la recherche scientifique (Centre Eau, Terre et Environnement), Université du Québec, 490 rue de la Couronne, Québec, QC, G1 K 9A9, Canada.
| | - Simon Besner
- Institut de recherche d'Hydro-Québec (IREQ), IREQ, 1800, boul. Lionel-Boulet, Varennes, QC, J3X 1S1, Canada.
| | - Jean-François Blais
- Institut national de la recherche scientifique (Centre Eau, Terre et Environnement), Université du Québec, 490 rue de la Couronne, Québec, QC, G1 K 9A9, Canada.
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21
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Floris B, Galloni P, Sabuzi F, Conte V. Metal systems as tools for soil remediation. Inorganica Chim Acta 2017. [DOI: 10.1016/j.ica.2016.04.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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22
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Huang Y, Fulton AN, Keller AA. Simultaneous removal of PAHs and metal contaminants from water using magnetic nanoparticle adsorbents. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 571:1029-1036. [PMID: 27450251 DOI: 10.1016/j.scitotenv.2016.07.093] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 07/13/2016] [Accepted: 07/14/2016] [Indexed: 06/06/2023]
Abstract
Many industrial wastewaters are contaminated with both heavy metal ions and organic compounds, posing a major threat to public health and the environment. In this study, magnetic nanoparticle adsorbents, namely Mag-PCMA-T, which contain a maghemite core and a silica mesoporous layer that permanently confines surfactant micelles within the mesopores, were synthesized to achieve simultaneous removal of polycyclic aromatic hydrocarbons (PAHs) (1mg/L) and metal contaminants (1mg/L). The individual removal efficiency of Cd(2+) and acenaphthene using Mag-PCMA-T was evaluated under a range of initial ion concentrations and adsorbent dosages, as well as the competitive adsorption with Cd(2+) and acenaphthene simultaneously present. The isotherms and kinetics of Cd(2+) and acenaphthene sorption onto Mag-PCMA-T were determined. Mag-PCMA-T removed >85% of the acenaphthene in <30min, with relatively high sorption capacity (up to 1060mg/kg). Mag-PCMA-T also exhibited high sorption capacity for Cd(2+) (up to 2250mg/kg). The simultaneous sorption performance was stable across a wide pH range (4-9) as well as in the presence of competitive metal ions (Ca(2+) and Mg(2+)) or natural organic matters. The Mag-PCMA-T can be regenerated and reused, providing a sustainable, fast, convenient, and efficient approach for water treatment.
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Affiliation(s)
- Yuxiong Huang
- Bren School of Environmental Science and Management, University of California, Santa Barbara, CA 93106, USA
| | - Aaron N Fulton
- Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Barbara, CA 93106, USA
| | - Arturo A Keller
- Bren School of Environmental Science and Management, University of California, Santa Barbara, CA 93106, USA.
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Liu MC, Chang SH, Chang MB. Catalytic hydrodechlorination of PCDD/Fs from condensed water with Pd/γ-Al2O3. CHEMOSPHERE 2016; 154:583-589. [PMID: 27088535 DOI: 10.1016/j.chemosphere.2016.03.135] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Revised: 02/27/2016] [Accepted: 03/29/2016] [Indexed: 06/05/2023]
Abstract
A continuous pyrolysis system (CPS) with effective air pollution control devices (APCDs) is designed and constructed to remediate the soil containing high-concentration PCDD/Fs. The quench tower of the APCDs system can capture the pollutants of high boiling points from the flue gas of CPS and produces condensed water of high PCDD/Fs concentration (16-44 ng I-TEQ/L), and needs further treatment. First, the result of activated carbon adsorption test displays the PCDD/Fs toxicity concentration of effluents meet the regulatory standards as the liquid to solid ratio is controlled at 3: 1. However, large amount of activated carbon need to achieve the high removal efficiency leads to high cost, so catalytic hydrodechlorination technology with Pd/Al2O3 as catalyst is applied to treat the condensed water. The PCDD/Fs mass removal efficiency achieved without the reducing agent is 53.21% with the operating time of 180 min. As 5% reducing agent (methanol) is added, the removal efficiency increases to 71.86%. In addition, to better understand the differences between molecular hydrogen and hydrogen donor, the condensed water was pre-aerated with hydrogen and catalytic hydrodechlorination test with palladium as catalyst was conducted. The results show that the PCDD/Fs mass removal efficiency increases to 97.34% with the operating time of 180 min, demonstrating the high PCDD/Fs removal efficiency of catalytic hydrodechlorination.
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Affiliation(s)
- Mei-Chen Liu
- Graduate Institute of Environmental Engineering, National Central University, 300 Jhongda Rd., Jhongli District, Taoyuan City, 320, Taiwan, ROC
| | - Shu-Hao Chang
- Graduate Institute of Environmental Engineering, National Central University, 300 Jhongda Rd., Jhongli District, Taoyuan City, 320, Taiwan, ROC
| | - Moo-Been Chang
- Graduate Institute of Environmental Engineering, National Central University, 300 Jhongda Rd., Jhongli District, Taoyuan City, 320, Taiwan, ROC.
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