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Murcia-Morales M, Tzanetou EN, García-Gallego G, Kasiotis KM, Vejsnaes F, Brodschneider R, Hatjina F, Machera K, Van der Steen JJ. Environmental assessment of PAHs through honey bee colonies - A matrix selection study. Heliyon 2024; 10:e23564. [PMID: 38187233 PMCID: PMC10770451 DOI: 10.1016/j.heliyon.2023.e23564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 11/12/2023] [Accepted: 12/06/2023] [Indexed: 01/09/2024] Open
Abstract
The steady conditions of temperature, humidity and air flux within beehives make them a valuable location for conducting environmental monitoring of pollutants such as PAHs. In this context, the selection of an appropriate apicultural matrix plays a key role in these monitoring studies, as it maximizes the information that will be obtained in the analyses while minimizing the inaccurate results. In the present study, three apicultural matrices (honey bees, pollen and propolis) and two passive samplers (APIStrips and silicone wristbands) are compared in terms of the number and total load of PAHs detected in them. Samplings took place in a total of 11 apiaries scattered in Austria, Denmark, and Greece, with analyses performed by GC-MS/MS. Up to 14 different PAHs were identified in silicone wristbands and pollen, whereas the remaining matrices contained a maximum of five contaminants. Naphthalene, 1-methylnaphthalene, 2-methylnaphthalene, and pyrene were found to be the most prevalent substances in the environment. Recovery studies were also performed; these suggested that the chemical structure of APIStrips is likely to produce very strong interactions with PAHs, thus hindering the adequate desorption of these substances from their surface. Overall, silicone wristbands placed inside the beehives proved the most suitable matrix for PAH monitoring through honey bee colonies.
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Affiliation(s)
- María Murcia-Morales
- Chemistry and Physics Department, University of Almeria, Agrifood Campus of International Excellence (ceiA3), 04120 Almería, Spain
| | - Evangelia N. Tzanetou
- Laboratory of Chemical Control of Pesticides, Department of Pesticides Control and Phytopharmacy, Benaki Phytopathological Institute, 145 61 Kifissia, Greece
| | - Guillermo García-Gallego
- Chemistry and Physics Department, University of Almeria, Agrifood Campus of International Excellence (ceiA3), 04120 Almería, Spain
| | - Konstantinos M. Kasiotis
- Laboratory of Pesticides' Toxicology, Department of Pesticides Control and Phytopharmacy, Benaki Phytopathological Institute, 145 61 Kifissia, Greece
| | | | - Robert Brodschneider
- Institute of Biology, University of Graz, Universitätsplatz 2, 8010 Graz, Austria
| | - Fani Hatjina
- Department of Apiculture, Institute of Animal Science, Ellinikos Georgikos Organismos ‘DIMITRA’, Nea Moudania GR-63200, Greece
| | - Kyriaki Machera
- Laboratory of Pesticides' Toxicology, Department of Pesticides Control and Phytopharmacy, Benaki Phytopathological Institute, 145 61 Kifissia, Greece
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Yi P, Zuo X, Liang N, Wu M, Chen Q, Zhang L, Pan B. Molecular clusters played an important role in the adsorption of polycyclic aromatic hydrocarbons (PAHs) on carbonaceous materials. CHEMOSPHERE 2022; 302:134772. [PMID: 35526686 DOI: 10.1016/j.chemosphere.2022.134772] [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: 03/05/2022] [Revised: 04/21/2022] [Accepted: 04/26/2022] [Indexed: 06/14/2023]
Abstract
Polycyclic aromatic hydrocarbons (PAHs) are one of the most frequently detected hydrophobic organic contaminants (HOCs) in the environment. They may form clusters because of the strong hydrophobic and π-π electron-donor-acceptor (EDA) interactions among PAHs molecules. However, previous experimental studies and theoretical simulations generally ignored the impact of molecular clusters on the adsorption, which may result in the misunderstanding of the environmental fate and risk. In this work, naphthalene (NAP), phenanthrene (PHE), and pyrene (PYR) were selected to investigate intermolecular interaction as well as the consequent impact on their adsorption on graphene. The density field of C atoms in equilibrium configurations of self-interacted PAHs suggested that the formation of PAHs molecular clusters was a spontaneous process, and was favored in solvents with stronger polarity and for PAHs with more benzene rings. It should be noted that the molecular dynamics simulations with the initial state of molecular clusters matched better with the published experimental results compared with those of individual PAHs. The formed compact PAHs clusters in polar solvents increased the apparent PAHs adsorption, because of their higher hydrophobic and π-π EDA interactions. This study emphasized that the self-interaction of PAHs should be carefully considered in both experimental and theoretical simulation studies.
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Affiliation(s)
- Peng Yi
- Yunnan Provincial Key Lab of Soil Carbon Sequestration and Pollution Control, Faculty of Environmental Science & Engineering, Kunming University of Science & Technology, Kunming, 650500, Yunnan, China
| | - Xiangzhi Zuo
- Yunnan Provincial Key Lab of Soil Carbon Sequestration and Pollution Control, Faculty of Environmental Science & Engineering, Kunming University of Science & Technology, Kunming, 650500, Yunnan, China
| | - Ni Liang
- Yunnan Provincial Key Lab of Soil Carbon Sequestration and Pollution Control, Faculty of Environmental Science & Engineering, Kunming University of Science & Technology, Kunming, 650500, Yunnan, China
| | - Min Wu
- Yunnan Provincial Key Lab of Soil Carbon Sequestration and Pollution Control, Faculty of Environmental Science & Engineering, Kunming University of Science & Technology, Kunming, 650500, Yunnan, China
| | - Quan Chen
- Yunnan Provincial Key Lab of Soil Carbon Sequestration and Pollution Control, Faculty of Environmental Science & Engineering, Kunming University of Science & Technology, Kunming, 650500, Yunnan, China.
| | - Lijuan Zhang
- School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510640, China
| | - Bo Pan
- Yunnan Provincial Key Lab of Soil Carbon Sequestration and Pollution Control, Faculty of Environmental Science & Engineering, Kunming University of Science & Technology, Kunming, 650500, Yunnan, China.
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Reduction in Toxicity of Polystyrene Nanoplastics Combined with Phenanthrene through Binding of Jellyfish Mucin with Nanoplastics. NANOMATERIALS 2022; 12:nano12091427. [PMID: 35564136 PMCID: PMC9105387 DOI: 10.3390/nano12091427] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 04/12/2022] [Accepted: 04/19/2022] [Indexed: 12/14/2022]
Abstract
Mucin (Mu), a biological substance extracted from jellyfish (Aurelia aurita), was used to reduce the toxic effect of polystyrene nanoplastics (PS-NP) combined with phenanthrene (Phe) in the aquatic environment of zebrafish (Danio rerio), among other aquatic organisms. Mu showed a high binding capacity, as it bound to 92.84% and 92.87% of the PS-NPs (concentration of 2.0 mg/L) after 0.5 h and 8 h, respectively. A zebrafish embryo development test was conducted to check for any reduction in toxicity by Mu. When exposed to PS-NP + Mu and PS-NP + Phe + Mu, respectively, the hatching rates were 88.33 ± 20.21% and 93.33 ± 2.89%, respectively; these results were not significantly different from those of the control group. However, the hatching rate with the addition of Mu increased, compared to that of the PS-NP (71.83 ± 13.36%) and Phe (37.50 ± 19.83%) treatments, and the morphological abnormality rate decreased. The presence of Mu was also found to obstruct the absorption of PS-NP and PS-NP + Phe by the zebrafish. When zebrafish embryos were exposed to PS-NP at a concentration of 5.0 mg/L, the hatching rate differed significantly from that of the control group, and the expression of CAT and p53 genes increased significantly, but the expression of Bcl-2 decreased significantly. An mRNA sequence analysis revealed that the gene expression levels of the test group containing Mu were similar to those of the control group. These results infer that Mu can be used as a biological material to collect and remove PS-NPs from aquatic environments and reduce toxicity.
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Bielská L, Škulcová L, Neuwirthová N, Cornelissen G, Hale SE. Sorption, bioavailability and ecotoxic effects of hydrophobic organic compounds in biochar amended soils. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 624:78-86. [PMID: 29247907 DOI: 10.1016/j.scitotenv.2017.12.098] [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: 10/30/2017] [Revised: 12/08/2017] [Accepted: 12/08/2017] [Indexed: 06/07/2023]
Abstract
This work addresses the effect of biochar amendment to soil on contaminant sorption, bioavailability, and ecotoxicity. A distinction between positive primary amendment effects caused by reduced toxicity resulting from contaminant sorption, and negative secondary amendment effects of the biochars themselves was seen. Two biochars (one from high technology and one from low technology production processes) representing real world biochars were tested for the adsorption of pyrene, polychlorinated biphenyl (PCB) 52), and dichlorodiphenyldichloroethylene (p,p'-DDE). Sorption by both biochars was similar, both for compounds in single and mixed isotherms, in the presence and absence of soil. p,p'-DDE natively contaminated and spiked soils were amended with biochar (0, 1, 5, and 10%) and bioavailability, operationally defined bioaccessibility and ecotoxicity were assessed using polyethylene (PE), polymeric resin (XAD) and Folsomia candida, respectively. At the highest biochar dose (10%), bioavailability and bioaccessibility decreased by >37% and >41%, respectively, compared to unamended soils. Mortality of F. candida was not observed at any biochar dose, while reproductive effects were dose dependent. F. candida benefited from the reduction of p,p'-DDE bioavailability upon 1% and 5% biochar addition to contaminated soils while at 10% dose, these positive effects were nullified by biochar-induced toxicity. p,p'-DDE toxicity corrected for such secondary effects was predicted well by both PE uptake and XAD extraction.
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Affiliation(s)
- Lucie Bielská
- RECETOX, Faculty of Science, Masaryk University, Brno, Czech Republic.
| | - Lucia Škulcová
- RECETOX, Faculty of Science, Masaryk University, Brno, Czech Republic
| | | | - Gerard Cornelissen
- Norwegian Geotechnical Institute (NGI), Department of Environmental Engineering, Oslo, Norway; Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Sarah E Hale
- Norwegian Geotechnical Institute (NGI), Department of Environmental Engineering, Oslo, Norway
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Ding T, Lü C, He J, Zhao B, Wang J, Zhou H, Zhang Y. Adsorption characteristics of Pb 2+ on natural black carbon extracted from different grain-size lake sediments. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:23911-23919. [PMID: 27628918 DOI: 10.1007/s11356-016-7647-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 09/07/2016] [Indexed: 06/06/2023]
Abstract
As a major organic component in aquatic sediments, black carbon (BC) could act as super surface sorbent for contaminants in soils or sediments due to its relatively structured carbon matrix with high degree of porosity and extensive surface area. In this work, the adsorption characteristics of Pb2+ were studied using BCs as adsorbents, which were extracted from four particle sizes of sediment from Lake Wuliangsuhai (WLSH), under conditions of different pH, BC content, and ionic strength. The results showed BC content near to 1 % of sediments from WLSH, in which BC1, BC2, BC3, and BC4 composited about 1.8, 1.6, 1.1, and 0.8 % in the sediment fractions of >180, 180-63, 63-32, and <32 μm, respectively. The specific surface area and the Pb2+ sorption capacity were increased with decreasing the particle size of BCs. Correspondingly, the adsorption percentage of Pb2+ increased with increasing initial pH and BC content but declined as the increase of ionic strengths. The Pb2+ sorption capacity was reached maximum at pH 5-6. Compared pre- to post-sorption BCs by SEM-EDS and FTIR, although the carboxyl (C=O) and phenol (OH) groups on BC fractions contributed to Pb2+ sorption, the main adsorption mechanism of BCs was the surface sorption at pH <6. Relatively, the contribution of BCs accounted for about 18 % of Pb2+ sorption capacity on sediments. This work is helpful to understand the environmental effects of different size fractions BCs extracted from natural sediments.
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Affiliation(s)
- Tao Ding
- College of Environment and Resources, Inner Mongolia University, Hohhot, 010021, China
- Institute of Environmental Geology, Inner Mongolia University, Hohhot, 010021, China
| | - Changwei Lü
- College of Environment and Resources, Inner Mongolia University, Hohhot, 010021, China.
- Institute of Environmental Geology, Inner Mongolia University, Hohhot, 010021, China.
| | - Jiang He
- College of Environment and Resources, Inner Mongolia University, Hohhot, 010021, China.
- Institute of Environmental Geology, Inner Mongolia University, Hohhot, 010021, China.
- College of Life Sciences, Inner Mongolia University, Hohhot, 010021, China.
| | - Boyi Zhao
- College of Environment and Resources, Inner Mongolia University, Hohhot, 010021, China
- Institute of Environmental Geology, Inner Mongolia University, Hohhot, 010021, China
- College of Life Sciences, Inner Mongolia University, Hohhot, 010021, China
| | - Jinghua Wang
- College of Environment and Resources, Inner Mongolia University, Hohhot, 010021, China
- Institute of Environmental Geology, Inner Mongolia University, Hohhot, 010021, China
- College of Life Sciences, Inner Mongolia University, Hohhot, 010021, China
| | - Haijun Zhou
- College of Life Sciences, Inner Mongolia University, Hohhot, 010021, China
| | - Yu Zhang
- College of Animal Science, Inner Mongolia Agricultural University, Hohhot, 010010, China
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Liu L, Fokkink R, Koelmans AA. Sorption of polycyclic aromatic hydrocarbons to polystyrene nanoplastic. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2016; 35:1650-5. [PMID: 26588181 DOI: 10.1002/etc.3311] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2015] [Revised: 08/14/2015] [Accepted: 11/18/2015] [Indexed: 05/02/2023]
Abstract
Microplastic has become an emerging contaminant of global concern. Bulk plastic can degrade to form smaller particles down to the nanoscale (<100 nm), which are referred to as nanoplastics. Because of their high surface area, nanoplastic may bind hydrophobic chemicals very effectively, increasing their hazard when such nanoplastics are taken up by biota. The present study reports distribution coefficients for sorption of polycyclic aromatic hydrocarbons (PAHs) to 70 nm polystyrene in freshwater, and PAH adsorption isotherms spanning environmentally realistic aqueous concentrations of 10(-5) μg/L to 1 μg/L. Nanopolystyrene aggregate state was assessed using dynamic light scattering. The adsorption isotherms were nonlinear, and the distribution coefficients at the lower ends of the isotherms were very high, with values up to 10(9) L/kg. The high and nonlinear sorption was explained from π-π interactions between the planar PAHs and the surface of the aromatic polymer polystyrene and was higher than for micrometer-sized polystyrene. Reduction of nanopolystyrene aggregate sizes had no significant effect on sorption, which suggests that the PAHs could reach the sorption sites on the pristine nanoparticles regardless of the aggregation state. Pre-extraction of the nanopolystyrene with C18 polydimethylsiloxane decreased sorption of PAHs, which could be explained by removal of the most hydrophobic fraction of the nanopolystyrene. Environ Toxicol Chem 2016;35:1650-1655. © 2015 SETAC.
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Affiliation(s)
- Lijing Liu
- Aquatic Ecology and Water Quality Management Group, Department of Environmental Sciences, Wageningen University, Wageningen, The Netherlands
| | - Remco Fokkink
- Physical Chemistry and Soft Matter, Wageningen University, Wageningen, The Netherlands
| | - Albert A Koelmans
- Aquatic Ecology and Water Quality Management Group, Department of Environmental Sciences, Wageningen University, Wageningen, The Netherlands
- Institute for Marine Resources & Ecosystem Studies, Wageningen UR, IJmuiden, The Netherlands
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Huang Z, Chua PE, Lee HK. Carbonized polydopamine as coating for solid-phase microextraction of organochlorine pesticides. J Chromatogr A 2015; 1399:8-17. [DOI: 10.1016/j.chroma.2015.04.028] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2015] [Revised: 04/16/2015] [Accepted: 04/17/2015] [Indexed: 11/30/2022]
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Dordio AV, Carvalho AJP. Organic xenobiotics removal in constructed wetlands, with emphasis on the importance of the support matrix. JOURNAL OF HAZARDOUS MATERIALS 2013; 252-253:272-92. [PMID: 23542322 DOI: 10.1016/j.jhazmat.2013.03.008] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2012] [Revised: 02/07/2013] [Accepted: 03/04/2013] [Indexed: 05/16/2023]
Abstract
Constructed wetlands (CWs) are increasingly popular as an efficient and economical alternative to conventional wastewater treatment processes for removal, among other pollutants, of organic xenobiotics. In CWs, pollutants are removed through the concerted action of their components, whose contribution can be maximized by careful selection of those components. Specifically for non-biodegradable organic pollutants, the materials used as support matrix of CWs can play a major role through sorption phenomena. In this review the role played by such materials in CWs is examined with special focus on the amount of research that has been conducted to date on their sorption properties relatively to organic compounds. Where available, the reports on the utilization of some of those materials on pilot or full-scale CWs are also recognized. Greatest interest has been directed to cheaper and widely available materials. Among these, clays are generally regarded as efficient sorbents, but materials originated from agricultural wastes have also gained recent popularity. Most available studies are lab-scale batch sorption experiments, whereas assays performed in full-scale CWs are still scarce. However, the available lab-scale data points to an interesting potential of many of these materials for experimentation as support matrix of CWs targeted for organic xenobiotics removal.
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Affiliation(s)
- A V Dordio
- Chemistry Department, University of Évora, Rua Romão Ramalho 59, 7000-671 Évora, Portugal.
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An C, Huang G. Stepwise adsorption of phenanthrene at the fly ash-water interface as affected by solution chemistry: experimental and modeling studies. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:12742-12750. [PMID: 23088491 DOI: 10.1021/es3035158] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Fly ash (FA) is predominantly generated from coal-fired power plants. Contamination during disposal of FA can cause significant environmental problems. Knowledge about the interaction of FA and hydrophobic organic pollutants in the environment is very limited. This study investigated the adsorption of phenanthrene at the interface of FA and water. The performance of phenanthrene adsorption on FA and the effects of various aqueous chemistry conditions were evaluated. The adsorption isotherms exhibited an increasing trend in the adsorbed amounts of phenanthrene, while a stepwise pattern was apparent. A stepwise multisite Langmuir model was developed to simulate the stepwise adsorption process. The adsorption of phenanthrene onto FA was noted to be spontaneous at all temperatures. The thermodynamic results indicated that the adsorption was an exothermic process. The adsorption capacity gradually decreased as pH increased from 4 to 8; however, this trend became less significant when pH was changed from 8 to 10. The binding affinity of phenanthrene to FA increased after the addition of humic acid (HA). The pH variation was also responsible for the changes of phenanthrene adsorption on FA in the presence of HA. High ionic strength corresponded to low mobility of phenanthrene in the FA-water system. Results of this study can help reveal the migration patterns of organic contaminants in the FA-water system and facilitate environmental risk assessment at FA disposal sites.
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Affiliation(s)
- Chunjiang An
- Institute for Energy, Environment and Sustainable Communities, University of Regina, Regina, Saskatchewan, Canada S4S 0A2
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Lou L, Wu B, Wang L, Luo L, Xu X, Hou J, Xun B, Hu B, Chen Y. Sorption and ecotoxicity of pentachlorophenol polluted sediment amended with rice-straw derived biochar. BIORESOURCE TECHNOLOGY 2011; 102:4036-4041. [PMID: 21215616 DOI: 10.1016/j.biortech.2010.12.010] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2010] [Revised: 11/30/2010] [Accepted: 12/01/2010] [Indexed: 05/30/2023]
Abstract
To investigate the feasibility of using biochar to control organic pollutants in sediments, we extracted biochar from rice-straw combustion residues (RBC) and studied its adsorption ability and effect on seed germination ecotoxicity of pentachlorophenol (PCP). The results showed that the Freundlich and dual-mode models could describe all the sorption isotherm data well, and the log K(OC) values increased with increasing RBC content. With 50 mg kg(-1) PCP in the sediment, a significant seed growth inhibition (P<0.01) was observed. The addition of 2.0% RBC lowered the PCP concentration in the extraction liquid from 4.53 to 0.17 mg L(-1) and increased the germination rate and root length significantly. Furthermore, it was found that the addition of RBC had no toxic but stimulative effect on root elongation. Consequently, RBC could serve as a potential supersorbent for the remediation of organic pollution in situ.
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Affiliation(s)
- Liping Lou
- Department of Environmental Engineering, Zhejiang University, Hangzhou 310029, People's Republic of China.
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Using Plants to Remove Foreign Compounds from Contaminated Water and Soil. PLANT ECOPHYSIOLOGY 2011. [DOI: 10.1007/978-90-481-9852-8_8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Vasilyeva GK, Strijakova ER, Nikolaeva SN, Lebedev AT, Shea PJ. Dynamics of PCB removal and detoxification in historically contaminated soils amended with activated carbon. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2010; 158:770-777. [PMID: 19897290 DOI: 10.1016/j.envpol.2009.10.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2008] [Revised: 09/16/2009] [Accepted: 10/05/2009] [Indexed: 05/28/2023]
Abstract
Activated carbon (AC) can help overcome toxicity of pollutants to microbes and facilitate soil bioremediation. We used this approach to treat a Histosol and an Alluvial soil historically contaminated with PCB (4190 and 1585 mg kg(-1), respectively; primarily tri-, tetra- and pentachlorinated congeners). Results confirmed PCB persistence; reductions in PCB extractable from control and AC-amended soils were mostly due to a decrease in tri- and to some extent tetrachlorinated congeners as well as formation of a bound fraction. Mechanisms of PCB binding by soil and AC were different. In addition to microbial degradation of less chlorinated congeners, we postulate AC catalyzed dechlorination of higher chlorinated congeners. A large decrease in bioavailable PCB in AC-amended soils was demonstrated by greater clover germination and biomass. Phytotoxicity was low in treated soils but remained high in untreated soils for the duration of a 39-month experiment. These observations indicate the utility of AC for remediation of soils historically contaminated with PCB.
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Affiliation(s)
- Galina K Vasilyeva
- Institute of Physicochemical and Biological Problems in Soil Science, Russian Academy of Sciences, Pushchino 142290, Russia.
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