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Tesi sul tema "Polychlorinated biphenyls"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 31 luglio 2024

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1

Beebe, Alexandrea. "Phytoremediation of airborne polychlorinated biphenyls". Thesis, University of Iowa, 2011. https://ir.uiowa.edu/etd/1123.

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Polychlorinated biphenyls (PCBs) contaminate every compartment of the environment including sediments, water, and air. Although their production has ceased, PCBs continue to contaminate the environment. The properties that make PCBs useful in industrial applications are the same properties that cause them to persistent in the environment. Phytoremediation has been proposed as an in situ treatment option for the remediation of these contaminants. Phytoremediation is the use of green plants to mitigate environmental pollution without excavation or treatment of the contaminated material. Hybrid poplar trees may be a feasible treatment candidate for scavenging airborne PCBs from nearby sources. PCBs are scavenged onto the leaves where a majority of the mass remains.

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2

Bozacıoğlu, Sevde Seza Sofuoğlu Aysun. "Air Monitoring of Polychlorinated Bibhenyls in Ambient Air of Suburban Area in İzmir, Turkey/". [s.l.]: [s.n.], 2004. http://library.iyte.edu.tr/tezler/master/cevremuh/T000440.doc.

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3

Demirtepe, Hale. "Modeling Anaerobic Dechlorination Of Polychlorinated Biphenyls". Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614079/index.pdf.

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This study aims to investigate the fate of polychlorinated biphenyls (PCBs) in sediments via using an anaerobic dechlorination model (ADM). PCBs are ubiquitous environmental pollutants, accumulated mostly in aquatic sediments. Significant attention was placed on the anaerobic dechlorination of PCBs since this process leads to the conversion of highly-chlorinated biphenyls to lower chlorinated ones, resulting in less toxic and more biodegradable congeners. An ADM was developed previously for the identification and quantification of anaerobic dechlorination pathways. In the present study, this model was improved and applied to laboratory and environmental sediment PCB data from Baltimore Harbor (BH), Maryland, USA, where PCB contamination has been recorded. The laboratory PCB data was from a 500 day microcosm study conducted with BH sediments which was used to validate the model, as well as to gather information on dominant dechlorination pathways affecting the sediments. ADM predicted the laboratory PCB data almost perfectly and subsequently very well predicted the environmental sediment PCB profiles. A complete identification and quantification of the anaerobic dechlorination pathways occurring in the BH sediments is achieved with this study for the first time. The significant similarity between the sediment sample PCB profiles and the model predicted profiles reveals that the BH sediments have undergone anaerobic dechlorination via a combination of previously identified dechlorination activities (N, P, M) with selective pathways. Model findings are consistent with microbial analysis of the sediments. Better understanding of anaerobic dechlorination mechanisms should aid in predicting natural attenuation of PCBs or developing bioremediation strategies for contaminated sites.

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4

Soyibo, Adeola Adewunmi. "Human dietary exposure to polychlorinated biphenyls". Thesis, Imperial College London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.430474.

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5

Eastling, Paul Michael. "Polychlorinated biphenyls in Cedar Rapids soil". Thesis, University of Iowa, 2010. https://ir.uiowa.edu/etd/492.

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Extreme flooding of rivers may contribute to increased loading of persistent organic pollutants (POPs) to the Great Lakes, the Mississippi river, and other large lakes and surface waters downstream of industrial and urban areas. This study examines the fate of POPs that were mobilized during heavy flooding of the Cedar River and the small urban city of Cedar Rapids, Iowa during the summer of 2008. This study focuses polychlorinated biphenyls (PCBs). We hypothesize that these PCBs were mobilized by the flood water and that residues remained in the soils and sediments of the residential areas of the city. To test our hypothesis, soil samples were collected from ~200 of residential locations in the downtown Cedar Rapids area and analyzed for the three compound groups. Samples were extracted using an accelerated solvent extraction (ASE 300), and analyzed using GC/ECD, GC/MSD and GC/MS/MS.

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6

Subramanian, Srishty. "MOLECULAR METHODS FOR ASSESSING THE RESPONSE OF ARABIDOPSIS THALIANA PLANTS TO POLYCHLORINATED BIPHENYLS AND HYDROXYLATED POLYCHLORINATED BIPHENYLS". Diss., Temple University Libraries, 2018. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/535049.

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Environmental Engineering
Ph.D.
Polychlorinated biphenyls (PCBs) are a class of persistent organic contaminants that are ubiquitous and persistent in the environment. In the environment, PCBs have been shown to undergo various degradation processes and generate hydroxylated metabolites known as hydroxylated polychlorinated biphenyls (OH-PCBs). There is a growing scientific interest in studying OH-PCBs as they are being increasingly detected in biotic and abiotic samples. Due to their widespread presence in the air, water, and soil, as well as their ability to bioaccumulate in living organisms, they pose a high danger to human beings and thus need to be remediated. Though phytoremediation has been proposed as a useful technology for the environmental management of PCBs, there is a lack of information about potential phytoremediation of OH-PCBs The hypothesis underlying this study is that hydroxylation of PCBs to OH-PCBs results in different toxicity and physiological effects on plants. In order to test this hypothesis, we conducted experiments aimed at understanding the toxicity and metabolism of PCBs and OH-PCBs by A. thaliana plants at physiological and transcriptomic levels. The applicability of FTIR to analyze lignin and cellulose content in the cell wall was tested for the purpose of biofuel production. More precisely, the specific aims of this study are as follows: 1. To determine the toxicity of selected PCBs and their hydroxylated metabolites (OH-PCBs) toward the model plant A. thaliana. 2. To understand the regulation of the response to and metabolism of PCBs and OH-PCBs in exposed A. thaliana at the transcriptomic level. 3. To determine the change in the biomass composition of A. thaliana upon exposure to different PCBs and OH-PCBs. Toxicity results indicated no observable toxicity of the parent PCBs toward the plants. However, lower chlorinated OH-PCBs resulted in a significant reduction in the growth and germination rate of the plants. Genome wide expression microarrays were used to investigate the transcriptional response of A. thaliana plants to 2,5-DCB and three of its OH-metabolites. Exposure to 2,5-DCB caused up-regulation of genes that are involved in toxic stress response and detoxification functions, and induction of multiple xenobiotic response genes. FTIR analysis was used to determine the effects of different PCBs and their hydroxylated metabolites on the composition of the plant biomass. Significant changes in the lignin and cellulose content were observed between different treatments, which indicated an overall effect on the cell wall components upon exposure to PCBs and its OH metabolites.
Temple University--Theses

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7

Geng, Shen. "INVESTIGATION OF THE TOXICITY AND EFFLUX OF POLYCHLORINATED BIPHENYLS AND HYDROXYLATED POLYCHLORINATED BIPHENYLS IN ESCHERICHIA COLI". UKnowledge, 2011. http://uknowledge.uky.edu/gradschool_theses/133.

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Polychlorinated biphenyls (PCBs) are persistent organic pollutants. Due to their properties, PCBs accumulate in the food-chain and post a threat to the health of human beings and wildlife. Hydroxylated PCBs (OH-PCBs) are oxidative metabolites of PCBs and are more hydrophilic than their parent PCBs. One of the best approaches to break down these contaminants is through bioremediation, which is an environmental friendly process that uses microorganisms to restore natural environment. Towards this goal, we have investigated the toxicity and accumulation of PCBs and OH-PCBs in a Gram-negative bacterium, Escherichia coli. We have also determined the role played by a primary multidrug efflux transporter AcrB on the accumulation of PCBs and OH-PCBs in bacterial cell. We found that one of the PCBs tested was toxic to E. coli, while different OH-PCBs have different levels of toxicity; the acrB knockout strain accumulated significantly more PCBs and OH-PCBs than the wild-type strain, suggesting that these compounds are substrates of the efflux pump; higher cytoplasmic concentrations of OH-PCBs were also observed in the acrB knockout strain using the biosensors. Based on these observations, we conclude that both PCBs and OH-PCBs are substrates of protein AcrB. Therefore the efflux activities of multidrug resistant pumps in Gram-negative bacteria should be considered while designing bioremediation approaches.

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8

Kaya, Devrim. "Attenuation Of Polychlorinated Biphenyls Under Anaerobic Conditions". Phd thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614933/index.pdf.

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Polychlorinated biphenyls (PCBs) are toxic and persistent anthropogenic contaminants. Concern on their adverse health effects has led to their regulation in air, water and/or soil in addition to sludge. Hence, removal of PCBs in various matrices, including transformer oils (TO) is a priority. This study aims to investigate PCB-118 and Aroclor 1254 toxicity and dechlorination by varying certain critical experimental components including electron donor (sludge or fatty acids), inocula (unacclimated or acclimated culture) and the doses of PCB and TO under anaerobic conditions. Anaerobic toxicity assays (ATA) reactors, lab-scale anaerobic batch digesters and sediment microcosms were used for this purpose. Increase in PCB-118 and TO doses affected anaerobic digester performance by negatively influencing methanogenesis, while favoring dechlorination only with the increase in PCB-118 dose. Up to 22% PCB-118 removal was attained with unacclimated culture. Studies with acclimated cultures showed Grasse River (GR) sediment to be the most active when compared to Fox River and Baltimore Harbor sediments. In GR sediment microcosms, PCB-118 and Aroclor 1254 removal efficiencies decreased when TO was present (1%), while 10% TO inhibited PCB dechlorination. Waste activated sludge was shown to be an effective electron donor, similar to fatty acids. Aroclor 1254 dechlorination was dechlorinated through removal of flanked meta and para chlorines, however, dechlorination pathways appeared to differ according to the presence/absence of TO. No ortho or unflanked chlorines were removed. Molecular tools (qPCR and DHPLC) were used to confirm the presence of active PCB dechlorinators. Dechlorination of PCBs was shown to be growth-linked.

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9

Phillips, Lyndal, University of Western Sydney, of Science Technology and Environment College e of Science Food and Horticulture School. "Analysis of polychlorinated biphenyls in transformer oils". THESIS_CSTE_SFH_Phillips_L.xml, 2002. http://handle.uws.edu.au:8081/1959.7/766.

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Polychlorinated Biphenyls (PCBs) were seen as a significant engineering advance when first commercially produced in 1929. They were used as insulators and cooling fluids in electrical transformers and capacitors. There are 209 PCB congenors that are chemically and thermally stable with low inflammability and reactivity. However,they are also highly toxic, suspected carcinogens and bioaccumulate in the food chain. Due to these characteristics they are listed by the United Nations as one of the sixteen worlds persistent organic pollutants POPs). By international agreement, undertaken by the UN, the production of PCBs has been banned and gradually their use will be phased out. Several tests and procedures are discussed in some detail in this research.
Master of Science (Hons)

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10

París, Pombo Alicia. "Assessment of dietary exposure to polychlorinated biphenyls". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ37974.pdf.

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11

Haag, Grönlund Marie. "Liver tumour promoting effects by polychlorinated biphenyls /". Stockholm, 1998. http://diss.kib.ki.se/1998/91-628-3203-4/.

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12

Phillips, Lyndal. "Analysis of polychlorinated biphenyls in transformer oil /". View thesis, 2002. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20031222.095244/index.html.

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Thesis (M.Sc.) (Hons.) -- University of Western Sydney, 2002.
A thesis submitted to the University of Western Sydney in fulfillment of the requirements for admission to the [degree of] Masters of Science (Honours). Bibliography : leaves 156-163.

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13

Madra, Sukhdeep. "Hepatic interaction of polychlorinated biphenyls and iron". Thesis, Brunel University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316990.

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14

Stemm, Divinia Nolasco. "INTERACTIONS BETWEEN SELENIUM AND POLYCHLORINATED BIPHENYLS (PCBs)". UKnowledge, 2005. http://uknowledge.uky.edu/gradschool_diss/472.

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This study investigated the interaction between polychlorinated biphenyls (PCBs) and selenium to explain the mechanism involved that could affect selenium metabolism and its anti-cancer property. PCBs congeners and mixtures were previously found to reduce hepatic Se and Se-dependent glutathione peroxidase activity. I hypothesized that certain PCB congeners affect selenium metabolism in the rat liver resulting in diminished antioxidant capacity of selenoproteins, which could alter the ability of Se to protect against PCBs induced tumor promotion. In the first study, the influence of 3,3,4,4-tetrachlorobiphenyl (PCB 77) on hepatic Se and glutathione peroxidase (GPx1) activity as well as cytochrome P450 1A1 induction was examined by employing a time-course study, which showed that PCB 77 significantly reduced the hepatic selenium level and GPx1 activity and that this effect was influenced by gender. The next study explored how PCB 77 could deplete hepatic selenium by determining selenium concentrations in different tissues, feces and urine. This study demonstrated that PCB-77 decreased hepatic Se by increased excretion of Se in urine but not in feces. Unlike glutathione peroxidase, thioredoxin reductase activity was not affected by PCB 77. The third study investigated the effect of selenium supplementation on the tumor promoting activity of PCB 77 and 2,2,4,4,5,5-hexaclorobiphenyl (PCB 153) using a 2-stage carcinogenesis model. Se supplementation did not diminish the induction of altered hepatic foci by coplanar PCB 77 or ortho-substituted PCB 153. Instead of protection, the number of foci per cubic centimeter and per liver among the PCB-77 treated rats was increased as the selenium dietary level increased. PCB 153 did not show the same selenium dose-response effect; nevertheless, selenium supplementation did not confer protection against foci development. On the other hand, supranutritional selenium reduced the mean focal volume. Supranutritional selenium or PCBs did not affect cell proliferation or thioredoxin reductase activity. Lastly, the use of the Zeeman graphite furnace atomic absorption spectrometry (GFAAS) method and closed microwave digestion technique for selenium determination of biological samples was compared with the neutron activation analysis and fluorometry methods. I found that GFAAS was not as reliable as the other methods.

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15

Fernandes, A. R. "Trace analysis and chemistry of polychlorinated biphenyls". Thesis, University of East Anglia, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384580.

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16

Koenig, Brenda Grace. "Latitudinal patterns of polychlorinated biphenyls (PCBs) in zooplankton". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq22914.pdf.

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17

O'Brien, Robert Thompson. "Ionization-induced regioselective dechlorination reactions of polychlorinated biphenyls". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/nq26884.pdf.

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18

Khmyl, Aliaksei L. "Phytoremediation of soil contaminated with polychlorinated biphenyls (PCBs)". Virtual Press, 2003. http://liblink.bsu.edu/uhtbin/catkey/1265088.

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19

Edgar, Petrena Joyce. "Biogeochemistry of polychlorinated biphenyls (PCBs) in estuarine sediments". Thesis, University of the West of Scotland, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343348.

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20

Bhalla, Renu. "BIOLOGICAL EFFECTS OF HYDROXYLATED METABOLITES OF POLYCHLORINATED BIPHENYLS". Master's thesis, Temple University Libraries, 2011. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/120626.

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Civil Engineering
M.S.E.
Polychlorinated biphenyls (PCBs) are widespread persistent organic pollutants. The metabolism of PCBs by various organisms involves many steps that can lead to the formation of a wide range of metabolites. These metabolites frequently exhibit a toxicity and biodegradability different than the parent compounds. There is currently little information available about the biological effects of PCB hydroxylated metabolites that can be generated by various organisms and potentially released into the environment. The objective of the present research is to compare the toxicity of selected PCB congeners and their corresponding mono-hydroxylated metabolites. To achieve this objective, the following specific aims were performed: (1) to determine the effect of selected PCBs and PCB hydroxylated metabolites on the growth rate of a model PCB-degrading bacterium, Burkholderia xenovorans LB 400, (2) to determine the microbial toxicity of PCBs and PCB metabolites using the bioluminescent assay Microtox®, and (3) to determine the estrogenicity of PCBs and PCB metabolites using the Yeast Estrogen Screen assay (YES). The effects of a range of PCBs (PCB-2, -3, -8, -9, -30, -35, -36, -39, -61, -68, and -79) and their mono-hydroxylated metabolites on the growth rate of the PCB degrader, Burkholderia xenovorans LB400, were recorded. The results showed that the parent PCBs (50 mg L-1) did not affect the growth rate of LB400 although their hydroxylated metabolites strongly inhibited microbial growth. Using Microtox® assay, Parent PCBs (50 mg L-1) did not exhibit observable toxicity, while their hydroxylated metabolites showed a high level of toxicity (EC50 ranges from 2 mg L-1 to 46 mg L-1). Results using the YES assay also showed that the estrogenicity of hydroxylated metabolites of PCBs (50 mg L-1) was higher than the parent PCBs. The results obtained from the present study show that mono-hydroxylated metabolites of PCBs are more toxic than the corresponding parent PCBs. Because hydroxylated PCB derivatives are produced by a range of organisms and potentially released into the environment, this work raises new concerns associated with the environmental fate of PCBs.
Temple University--Theses

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21

Hung, Wing Yee. "Biological sensing of polychlorinated biphenyls by bioluminescence zebrafish". HKBU Institutional Repository, 2010. http://repository.hkbu.edu.hk/etd_ra/1166.

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22

O'Brien, Robert Thompson 1965 Carleton University Dissertation Chemistry. "Ionization-induced regioselective dechlorination reactions of polychlorinated biphenyls". Ottawa.:, 1997.

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23

Toaspern, Megan L. "Bioaccumulation of polychlorinated biphenyls in the Delaware River estuary". College Park, Md. : University of Maryland, 2003. http://hdl.handle.net/1903/267.

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Thesis (M.S.) -- University of Maryland, College Park, 2003.
Thesis research directed by: Marine, Estuarine, Environmental Sciences Graduate Program. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.

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24

Lv, Zhe. "Environmental biotransformation of chiral polychlorinated biphenyls and their metabolites". ACS Publications, 2010. http://hdl.handle.net/1993/22286.

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This dissertation combines laboratory and field experiments to investigate the mechanisms of atropisomer enrichment for chiral polychlorinated biphenyls (PCBs) and their metabolites in organisms. Stereoselective biotransformation and bioaccumulation were identified as two major reasons for the different environmental fate of PCB atropisomers. Other affecting factors, such as presence of nanoparticles and changes in feeding ecology of organisms, also affect the fate of chiral contaminants. In vitro incubations of rat cytochrome P-450 2B1 (CYP2B1) isozyme with chiral PCBs indicated that different biotransformation kinetics and competition among PCB congeners or between atropisomers were two main factors affecting atropisomer enrichment. Different interactions between chiral PCB congeners or atropisomers with rat CYP2B1 may occur at the molecular level. Non-racemic meta-hydroxylated-PCBs (5-OH-PCBs) were the major metabolites. CYP-mediated stereoselective formation of dihydroxylated PCBs from OH-PCBs was observed. Gold nanoparticles affected biotransformation activity of rat CYP2B1 and changed PCB atropisomeric composition, directly by electrostatic interaction, or indirectly by changes to the surrounding ionic strength. Thus, stereoselective metabolism of chiral PCBs and OH-PCBs by CYPs is a major mechanism for atropisomer enrichment of PCBs and their metabolites in the environment, with the degree of enrichment dependent, at least in part, on charged nanoparticles and stereoselective interference of atropisomers with each other at the enzyme level. The atropisomer compositions of chiral PCBs were measured in the marine biota of Cumberland Sound (Canada) and Svalbard (Norway). High trophic level organisms, including harp seal, beluga, and narwhal reported for the first time, had species-specific atropisomer signatures, likely due to a combination of in vivo biotransformation and trophic transfer. PCB chiral signatures in Greenland sharks supported the hypothesis that some of these PCB atropisomer compositions shifted over time and space, possibly due to a change in feeding ecology. To our knowledge, this is the first report to investigate temporal trends of PCB atropisomer signatures in Arctic biota.

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25

Hope, Kjell. "Polychlorinated Biphenyls in Major Foodstuffs on the Canadian Market". Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-71513.

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26

Agarwal, Shirish. "Palladium/Magnesium Bimetallic Systems for Dechlorination of Polychlorinated Biphenyls". Cincinnati, Ohio : University of Cincinnati, 2009. http://www.ohiolink.edu/etd/view.cgi?acc_num=ucin1236037376.

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Thesis (Ph.D.)--University of Cincinnati, 2009.
Advisors: Dionysios Dionysiou (Committee Chair), Souhail Al-Abed (Committee Member), George Sorial (Committee Member), Margaret Kupferle (Committee Member). Title from electronic thesis title page (viewed April 22, 2009). Keywords: PCBs; Dechlorination; Pd/Mg; Bimetallic; Reduction pathway; intermediates; aggressive anions; sediment; nano-synthesis; nano-scaling; sulfide poisoning. Includes abstract. Includes bibliographical references.

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Sun, Yifei. "Decomposition of polychlorinated biphenyls with activated carbon-supported iron". 京都大学 (Kyoto University), 2006. http://hdl.handle.net/2433/136149.

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28

Khesuoe, Malefetsane Patrick. "Electrochemical polychlorinated biphenyls immunosensor based on functionalized polyaniline nanocomposite". Thesis, Cape Peninsula University of Technology, 2015. http://hdl.handle.net/20.500.11838/2321.

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Thesis (MTech (Chemistry))--Cape Peninsula University of Technology, 2015.
Immunosensors are analytical devices comprising antibody (Ab) molecules intimately integrated with electronic physicochemical transducers. Abs are responsible for specific recognition of an analyte so called antigen (Ag) while transducers are responsible for the conversion of chemical changes brought about by Ab-Ag interactions into measurable and processable signal. Amongst the many analytical tools, immunosensors have shown outstanding performance in applications in fields such as clinical diagnostics, agricultural purposes and environmental monitoring. They have come in place of the many conventional analytical methods which showed a number of disadvantages; high cost and longer time of operation, and requirement of highly knowledgeable personnel. On the other hand, immunosensors have shown potential to overcome these constraints. Their advantages include possibilities of portability, miniaturization, and simplified procedures. Of the possible fields of immunosensor applications, this study focussed on the environmental aspect. The safety of the environment is good for the well-being even though there are still some environmental threats that exist. Polychlorinated biphenyls (PCBs) have reportedly been found to be some of the potential substances to pose such threats due to their toxic and persistent behaviour. In this study, we have developed an electrochemical immunosensor as an analytical tool for the analysis and monitoring of PCBs. The development was based on the use of silver nanoparticles-doped polyaniline (PANI/Ag NPs) for modification of an electrode as a process for fabrication of the transducer. The PANI/Ag NPs composite was deposited on the glassy carbon (GC) and platinum (Pt) electrodes by oxidative electropolymerization of aniline in the presence of Ag NPs in 1 M HCl using cyclic voltammetry (CV) by ramping the potential from -0.1 to 1.4 V at 50 mV/s. The composite was then characterized and evaluated as a potential material for electrochemical transduction. Evaluation was on electroactivity, which is the main property of interest for materials used in the fabrication of electrochemical devices. The PANI composites were characterized using spectroscopic (FTIR), microscopic (TEM) and electrochemical CV techniques. Results confirmed the formation of PANI in its emeraldine form and the presence of Ag NPs. Characteristic functional groups and peaks of PANI were observed in FTIR and CV respectively. TEM micrograms showed one dimensional nanofibric tubes and crystalline-like structure of the composite. The incorporation of Ag NPs was indicated by the transition from the amorphous (PANI) to crystalline (PANI/Ag NPs) structure accompanied by increase in size as well as smoothness of the tubes. EDS-TEM counts increase of the chlorine (Cl) peaks is due to the closeness of these peaks to those of Ag, thus confirming incorporation of Ag NPs.

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Frederick, Karen S. "A characterization of the effects of polychlorinated biphenyl mixtures on the expression of peptidylglycine [alpha]-amidating monooxygenase in neuroendocrine cells". Connect to this title online, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=bgsu1151328382.

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Juan, Ching-yi Amy. "Studies on the intake and behaviour of PCBs in humans". Thesis, Lancaster University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274223.

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31

Stewart, Kenneth L. "State-wide fish tissue contaminants survey and effects of feeding type, season and gender on fish tissue contamination levels". Morgantown, W. Va. : [West Virginia University Libraries], 2009. http://hdl.handle.net/10450/10722.

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Thesis (M.S.)--West Virginia University, 2009.
Title from document title page. Document formatted into pages; contains iv, 145 p. : ill. (some col.), col. map. Includes abstract. Includes bibliographical references.

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DUIGNAN, DAVID BERNARD. "IN VITRO METABOLISM OF POLYCHLORINATED BIPHENYLS BY DOG HEPATIC CYTOCHROMES P-450". Diss., The University of Arizona, 1987. http://hdl.handle.net/10150/184156.

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The biochemical basis for the unique ability of Beagle dog liver microsomes to metabolize 2,2',4,4',5,5'-hexachlorobiphenyl (245-HCB) was investigated. The major phenobarbital (PB)-inducible cytochrome P-450 isozyme, called PBD-2, was purified to 95% homogeneity from liver microsomes of both control and PB-treated dogs, as evidenced by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. In a reconstituted system containing cytochrome b₅, PBD-2 metabolized 245-HCB at a rate greater than three-fold that seen in liver microsomes from PB-treated dogs. Immunoblot analysis revealed that, upon PB treatment, the increase in the level of PBD-2 in dog liver microsomes correlated well with the increase in the rate of hepatic microsomal metabolism of 245-HCB by dogs. Anti-PBD-2 IgG caused a > 90% inhibition of 245-HCB metabolism by microsomes obtained from control and PB-treated dogs. Studies were also conducted to assess the ability of PBD-2 to metabolize 2,2',3,3',6,6'-hexachlorobiphenyl (236-HCB) and 4,4'-dichlorobiphenyl (4-DCB). Dog liver microsomes readily metabolized 236-HCB, and PB treatment led to a dramatic increase in this rate of metabolism, suggesting a role for PBD-2 in the metabolism of 236-HCB. In a reconstituted system containing cytochrome b₅, PBD-2 metabolized 236-HCB at a rate greater than two-fold that observed in microsomes from PB-treated dogs. Pretreatment of microsomes obtained from PB-treated dogs with chloramphenicol (a highly selective inactivator of PBD-2) caused a nearly 70% decrease in the microsomal metabolism of 236-HCB. Anti-PBD-2 IgG inhibited by > 90% 236-HCB metabolism by microsomes from both control and PB-treated dogs. In contrast, PB treatment caused no significant alteration in the metabolism of 4-DCB by dog liver microsomes, and PBD-2 metabolized this compound poorly, even in the presence of cytochrome b₅. Taken together, these data indicate that the dog hepatic cytochrome P-450 isozyme, PBD-2, is present in microsomes obtained from both control and PB-treated animals. PBD-2 is responsible for the microsomal metabolism of 245-HCB, and this isozyme likely accounts for the unique ability of Beagle dogs to readily metabolize and eliminate this compound in vivo. The data also strongly suggest that PBD-2 is responsible for the microsomal metabolism of 236-HCB in dogs. However, PBD-2 is not likely involved in the microsomal metabolism of 4-DCB by this species.

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33

Magan, Christopher L. "Human health risk characterization for dietary exposure to polychlorinated biphenyls (PCBs) in fish from the Columbia Basin Irrigation Project a probabilistic approach /". Pullman, Wash. : Washington State University, 2009. http://www.dissertations.wsu.edu/Thesis/Spring2009/c_magan_041709.pdf.

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Thesis (M.S. in environmental science)--Washington State University, May 2009.
Title from PDF title page (viewed on May 28, 2009). "School of Earth and Environmental Sciences." Includes bibliographical references (p. 56-63).

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34

Kuipers, Bianca. "Microbial degradation of polychlorinated biphenyls and alkylated polycyclic aromatic hydrocarbons". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0017/NQ48650.pdf.

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35

Valentin, Melissa McShea. "Laboratory study of solvent extraction of polychlorinated biphenyls in soil". Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=31553.

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Polychlorinated biphenyls (PCBs) are toxic, stable organic contaminants that are present in air, water, soil, plants and animals all around the world. The market for PCB treatment technologies is estimated to be $300 to $600 million (Canadian dollars) for the year 2000, and will expand in future years. Existing treatment technologies to remove PCBs from soil are underutilized because they are more expensive than landfilling and incineration. This thesis presents a laboratory study of an innovative PCB remediation process that will extract PCBs from soil in-situ for subsequent destruction above ground. This remedy will remove PCBs from surficial soil without the need for excavation. Two laboratory studies were conducted on field-contaminated soil. The first experiment evaluated the effectiveness of hexane, methyl isobutyl ketone, and ethyl acetate in removing PCBs from soil. Ethyl acetate and MIBK were equally effective, removing 99% and 98% of PCBs from dry soil in 4 days, respectively. In the second experiment, soil was exposed to ethyl acetate for varying amounts of time, and some of the samples were treated a second time with fresh solvent. PCB removal increased as treatment time was increased from 10 minutes to 50, 250, and 1250 minutes, but the rate of PCB removal decreased as treatment time increased. The second 10-minute extraction removed an additional 1--10% of the remaining PCBs.

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36

Duarte-Davidson, Raquel V. "Polychlorinated biphenyls and other organic contaminants in the Welsh population". Thesis, Lancaster University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358065.

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37

Pillai, Mahesh Ramachandran. "Deciphering the Link Between Polychlorinated Biphenyls, Immune Function and Exercise". Bowling Green State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1510140839084446.

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38

Asbrock, Christina Marie. "Influence of a mixture of two polychlorinated biphenyls (PCB 47/77) on pro-inflammatory cytokines (IL-6, TNF-[alpha]) and associative behavior in young Sprague-Dawley rats". Connect to this title online, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=bgsu1162788653.

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39

McDonald, Jennifer C. Venables Barney J. "Bacterial challenge in Lumbricus terrestris a terrestrial invertebrate immunotoxicity model /". [Denton, Tex.] : University of North Texas, 2007. http://digital.library.unt.edu/permalink/meta-dc-3640.

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40

Krishnan, Dena N. "Neurobehavioral and neuroendocrine assessment of rats perinatally exposed to polychlorinated biphenyls a possible model for autism /". Bowling Green, Ohio : Bowling Green State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=bgsu1182708278.

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41

Hayes, Jennifer Marie. "PCB (Aroclor 1242) mobility in soil as affected by various solvents". Virtual Press, 1990. http://liblink.bsu.edu/uhtbin/catkey/722791.

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For the past several decades, industry has filled lagoons and landfills with significant quantities of polychlorinated biphenyls (PCBs). Other wastes such as carbon tetrachloride and various alcohols have mixed with PCBs. Soil columns spiked with Aroclor 1242 were leached with such solvents. Ninety-one days of deionized water flow did not move a detectable amount of Aroclor 1242 more than 2 cm. through soil columns. Sixty-nine days was sufficient time for an alcohol mixture to carry Aroclor 1242 over 7 cm, the soil depth of the column. Five days was sufficient time for carbon tetrachloride: ethanol to carry Aroclor 1242 the same distance. A mixture of organic solvents can promote mobility of lipophilic organics such as polychlorinated biphenyls in the soil when water alone would not be effective. While assessing the extent of a chemical spill or the contamination resulting from improper disposal, it is clear that the interactions of chemical contaminants must be considered.
Department of Natural Resources

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42

DeVor, Robert William. "Determination of the degradation mechanism for polychlorinated biphenyl congeners using mechanically alloyed magnesium/palladium in methanol". Orlando, Fla. : University of Central Florida, 2008. http://purl.fcla.edu/fcla/etd/CFE0002112.

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43

Fletcher, Andrew Edward David. "Catalytic dechlorination of polychlorinated biphenyls (PCBs) using new organotransition metal catalysts". Thesis, University of Oxford, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.487287.

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Abstract (sommario):

The aim of this thesis is to explore the Schwartz reaction, a method for the catalytic dechlorination of polychlorinated biphenyls (PCBs). Chapter One introduces PCBs, their stability and industrial utility, their subsequent detection in the environment and concerns over their human health effects leading to a political will for remediation 0 of PCB contaminated land. Natural, physical, biological and chemical destruction methods o for PCBs are then reviewed. The chapter concludes by introducing the Schwartz reaction which uses CP2TiCh, NaBH4 and pyridine in diglyme to dechlorinate PCBs. Its advantages and disadvantages are highlighted. Chapter Two studies the mechanism of the Schwartz reaction using a variety of techniques. A DFT study is described, reaction conditions are explored and a proposed intermediate (Cp2TiHpyr) is isolated and characterised with the aid of deuterium labelling. A Schwartz reaction using CP2TiHpyr is carried out in an EPR tube, conclusions are drawn about the Ti(III) species present therein and a modified mechanism is proposed. Chapter Three tests a variety ofnew catalysts for dechlorination ofPCBs. The original CP2TiCh catalyst is altered by variation of the ligands and the metal and other new systems containing an '(Tl-arene)FeCp' moiety are tested. New catalytic systems are presented including precursor compounds which are air and moisture stable. Chapter Four investigates the removal of toxic pyridine as a requirement for the Schwartz reaction. Alternative bases are tested and conclusions drawn about the role of the base in the mechanism. Transition metal complexes are then prepared which incorporate an amine (NMe2 or NtBu) or pyridine functionalised arm into the ligand framework. lIB NMR spectroscopy is used to observe the amine'BH3 adducts present in the reaction mixture and provide new insights into the reaction mechanism. Chapter Five explores heterogenisation of the Schwartz reaction by synthesising a range of titanocene functionalised polystyrenes. These are characterised using solid state IH NMR (MAS), TGA and EDX. These solids are then tested for their catalytic activity. Experimental procedures are documented in Chapter Six and characterising data for all new or previously uncharacterised compounds are given in Chapter Seven. Asummary of all catalytic data from Schwartz reactions in this thesis is given in Appendix One. DFT, EPR and crystal structure data are given in the Electronic Appendix.

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44

Sassani, Ramin. "Toxicity of Polychlorinated Biphenyls (Aroclor 1254) on the Earthworm Eisenia foetida". Thesis, University of North Texas, 1991. https://digital.library.unt.edu/ark:/67531/metadc500593/.

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Objectives were to: (1) assess toxicity of polychlorinated biphenyls on Eisenia foetida, in terms of survival (LC5O/LD5O), and suppression of coelomocytes to form secretory (SR) and erythrocyte rosettes (ER) with, and to phagocytize rabbit erythrocytes; and (2) compare results with those of Lumbricus terrestris to assess relative sensitivities to PCB. Using 5-d filter paper contact exposure protocol, LC50 and LD50 were 30.4 cg/cm2 and 4450 cg/g dry mass, respectively. Nominal PCB exposure concentrations of 5.0 and 10.0 pg/cm2 resulted in tissue levels of 1389 and 2895 pg/g dry mass causing a significant reduction in SR formation by 18 and 52%, respectively. ER formation and phagocytosis were reduced significantly (52 and 61%) only at the higher tissue concentration. Compared to reported data on lethality and immunomodulation in L. terrestris, E. foetida appears to be more resistant.

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45

Regular, Stephen. "A novel fluorescence method for screening of polychlorinated biphenyls in soils". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ55947.pdf.

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46

Drouillard, Kenneth G. "Modeling the toxicokinetics and biomagnification of polychlorinated biphenyls (PCBs) in birds". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ58001.pdf.

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47

Boumphrey, Ruth Susan. "Polychlorinated biphenyls in the North Atlantic Gannet : temporal and spatial trends". Thesis, Lancaster University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246142.

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48

Burke, Megan Elizabeth. "Mass balance modeling of polychlorinated biphenyls in the Lower Duwamish Waterway". Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/104192.

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Thesis: M. Eng., Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2016.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 30-31).
Remediation is most effective when a site is properly characterized. The Lower Duwamish Waterway (LDW) in Seattle, Washington is contaminated with polychlorinated biphenyls (PCBs). A zero dimensional mass balance of the 5 mile long waterway, which ends in Elliott Bay, helps to determine the different sources and concentrations of PCBs within the Lower Duwamish Waterway to aid future remedial activities. There are four unknown state variables: freshness, suspended sediment concentration, dissolved phase total PCB concentration, and sorbed phase total PCB concentration. The sole freshness source was the Green River and the freshness sink was the flushing at the downstream mouth. PCBs exist in sorbed and freely dissolved phases. Sorbed PCB sources include: the incoming Green River, laterals, and erosion. Sinks of sorbed PCBs include: deposition, flushing, and desorption. The Green River, laterals, diffusion, and desorption are all dissolved PCB sources, while the sinks are flushing and volatilization to the atmosphere. The calculated four state variables were compared to measured values and a sensitivity analysis was performed on the sources.
by Megan Elizabeth Burke.
M. Eng.

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49

Li, Miao. "Protein adducts and crosslinking by reactive metabolites of polychlorinated biphenyls (PCBs)". Diss., University of Iowa, 2015. https://ir.uiowa.edu/etd/1984.

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Abstract (sommario):

Polychlorinated biphenyls (PCBs) are the persistent environmental pollutants with the continuous concerns over adverse human health effects. As semi-volatile compounds, PCBs were found in indoor and outdoor air. The observation of high levels of airborne PCBs in old school buildings raised the concerns of inhalation exposure and toxicity of PCBs. Lower chlorinated PCBs (LC-PCBs), major components of airborne PCBs, are subject to biotranformation. In vitro and in vivo studies revealed that reactive metabolites of LC-PCBs formed covalent adducts on DNA and proteins. The hypothesis of the project is that the reactive metabolites of LC-PCBs are able to form adducts on proteins or even protein crosslinks, and the formation of protein adducts and crosslinks causes the dysfunction of the target proteins. In addition, the objectives of the project are also to identify protein targets by PCB metabolites, which may be related to the mechanism of toxicity of LC-PCBs. The alkaline permethylation (AP) was established and optimized to identify and measure the protein adducts from LC-PCB metabolites. The AP method evidenced PCB metabolites formed protein adducts through the sulfhydryl groups and also one molecule of PCB quinoid metabolites was able to bind to more than one protein. Application of cytochrome c as the model protein revealed PCB quinoid metabolites also formed adducts on lysine and glutamic acid. The adduct formation and crosslinks caused the dysfunction of cytochrome c. In addition, the quinone protein adducts still kept the ability for redox reactions, which may lead to unexpected toxicity. The SILAC method was applied to identify the target proteins in the samples of in vitro proteome incubation. The instability of PCB quinone protein adducts was found by further reaction of quinone protein adducts. This may be the reason why cysteine-PCB quinone adducts were not frequently identified by proteomics method. The further understanding of protein adducts by reactive PCB metabolites helps to identify the target proteins, and ultimately reveal the role of protein adducts impacting on human health.

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50

Eyambe, George Sona. "Cellular Biomarkers for Measuring Toxicity of Xenobiotics: Effects of PCBs on Earthworm Lumbricus Terrestris Coelomocytes". Thesis, University of North Texas, 1991. https://digital.library.unt.edu/ark:/67531/metadc332716/.

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The research presented herein provides information on coelomocyte (leukocyte) collection, function and immunotoxicity from polychlorinated biphenyls (PCB) in the earthworm Lumbricus terrestris. Research was undertaken as part of an overall goal to develop a well-documented and scientifically valid non-mammalian surrogate immunoassay with the earthworm Lumbricus terrestris to assess immunotoxic potential of xenobiotics. The principal objectives were to: (1) Develop an extrusion model for analyzing immunotoxicity of xenobiotics; (2) determine if coelomocytes can be collected repeatedly without obvious harm to the earthworm or change in immune response of the coelomocytes harvested and (3) validate the response sensitivity profiles of a panel of biomarkers {differential and total cell counts, erythrocyte rosette (ER) and secretory rosette (SR) formation with, and phagocytosis of antigenic rabbit red blood cells} in earthworms after acute exposure to a known mammalian and L. terrestris immunotoxin, the PCB Aroclor 1254.

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