Transplacental Transfer of PCBs and Chlorinated Hydrocarbon Pesticides from the Pregnant Striped Dolphin (Stenella coeruleoalba) to Her Fetus

Transplacental transfer of chlorinated hydrocarbons such as PCBs, DDT compounds, HCH isomers and HCB was determined in a pregnant striped dolphin just before parturition. The transfer rates of chlorinated hydrocarbons in the striped dolphin through parturition were estimated as follows: PCBs 4.0%, ΣDDT 4.7%, ΣHCH 8.9% and HCB 9.4%. The concentration ratios of chlorinated hydrocarbons in the blubber of the fetus to that of the mother dolphin were found to be in the order of HCB > HCH isomers > DDT compounds > PCBs. Especially in PCB congeners, these ratios gradually decreased with the increase of chlorine atoms substituted in biphenyls.

These observations indicate that the more lipophilic chemicals, such as higher chlorinated biphenyls and DDT compounds, are less transferable from mother to fetus. The transfer characteristics of chlorinated hydrocarbons can be explained by their equilibrium partitionings between blood and blubber, resulting from the differences of lipid compositions in each.     

Elevated Concentrations of Pesticides and PCBs in Soils at the Southern Caspian Sea (Iran) are Related to Land Use

Soil contamination by organochlorine pesticides or PCBs is almost undocumented for Iran. Here we report a soil survey in Mazandaran and Guilan provinces that hold >30% of the agricultural areas of Iran where pesticide use is widespread. Concentration of DDTs, HCHs, cyclodienes, and PCBs were measured in 45 soil samples from different agricultural land uses and forest land. The average concentrations of ∑DDT (37 μg kg^?1) and ∑HCH (21 μg kg^?1) in agricultural soils are among the largest ever reported and exceed international soil screening standards. All residues were larger in agricultural than in forest soil. Within agricultural land, ∑DDT were largest for tea gardens, lindane was largest in rice fields, and cyclodiens largest in citrus orchards. The ratio of (DDD + DDE)/DDT is an index of the extent of DDT degradation in soil and was lower in tea gardens than in other soils (0.7 versus 2–5), indicating either ongoing DDT input or lower degradation rate in the tea gardens that are more acid than the other soils (pH 4.5 versus 6.5–7.0). The o,p′–DDT/p,p′–DDT ratio was about 3 in forest soils, suggesting that DDT is derived from dicofol application and not from technical DDT as in agricultural soils. The PCB 28, 180, and 138 showed the highest mean concentration compared with other PCB congeners in all land uses. This survey is the first of this kind for Iran and illustrates that concentrations of organochlorine pesticide in soil are relatively large.     

DDT and HCH (Organochlorine Pesticides) in Residential Soils and Health Assessment for Human Populations in Korba,India

Dichlorodiphenyltrichloroethane (DDT), hexachlorocyclohexane (HCH), and their isomers’ levels in residential soils were determined for the assessment of health risk in Korba, India. Observed concentrations of total HCH and total DDT in soils were more or less comparable with other parts of India and the world. ΣHCH and ΣDDT concentrations ranged between 0.9–20 μg kg^?1 and 2–315 μg kg^?1, respectively, which were lower than recommended soil quality guidelines indicating low ecotoxicological risk. Carcinogenic and non-carcinogenic impacts of HCH and DDT on human populations through soil ingestion were evaluated and presented. The incremental lifetime cancer risk (ILCR) for adults and children ranged between 7.8 × 10^?10–1.6 × 10^?7 and 4.1 × 10^?9–8.2 × 10^?7, respectively. Non-cancer health hazard quotient (HQ) ranged between 5.9 × 10^?7–1.8 × 10^?3 and 3.1 × 10^?6–9.4 × 10^?3, respectively, for adults and children. The estimated ILCR and HQ were within the safe acceptable limits of 10^?6–10^?4 and ≤1.0, respectively, indicating low risk to human populations from exposure to organochlorine pesticides (HCH and DDT) in the study area.     

Diversity, distribution and divergence of lin genes in hexachlorocyclohexane-degrading sphingomonads

Two forms of hexachlorocyclohexane (HCH), gamma-HCH (lindane) and technical HCH (incorporating alpha-, beta-, gamma- and delta- isomers), have been used against agricultural pests and in health programs since the 1940s. Although all the isomers are present in the milieu, delta- and beta-HCH isomers are the most problematic and present a serious environmental problem. Bacteria that degrade HCH isomers have been isolated from HCH contaminated soils from different geographical locations around the world (from the family Sphingomonadaceae). Interestingly, all these bacteria contain nearly identical lin genes (responsible for HCH degradation), which are diverging to perform several catabolic functions. The organization and diversity of lin genes have been studied among several sphingomonads, and they have been found to be associated with plasmids and IS6100, both of which appear to have a significant role in their horizontal transfer. The knowledge of the molecular genetics, diversity and distribution of lin genes, and the potential of sphingomonads to degrade HCH isomers, can now be used for developing bioremediation techniques for the decontamination of HCH contaminated sites.     

Quantification of nitrophenols,chlorophenols, and hexachlorocyclohexanes in agricultural soils in the vicinity of industrial area for the assessment of human health hazard and risk

In this study, quantification of nitrophenol (NP), chlorophenol (CP), and hexachlorocyclohexane (HCH) compounds in agricultural soils in the vicinity of the industrial region in northern Uttar Pradesh, India was carried out for the assessment of human health hazard. The concentration of ∑NP, ∑CP, and ∑HCH compounds ranged 0.33–3.64 mg kg^?1, 0.06–3.18 μg kg^?1, and 1.23–17.24 mg kg^?1, respectively, and were within the soil quality guidelines for the protection of human and environment health. Human health hazard index and cancer risk, on the basis of average daily intake of these compounds through soil for human adults and children, was lower than the acceptable limit. This study suggested low health hazard and risk due to phenolic and HCH compounds to human population.     

Organochlorine Pesticides in Sediments around Chaohu Lake: Concentration Levels and Vertical Distribution

Eighteen organochlorine pesticides (OCPs) were investigated in surface sediments from the Nanfei River and in four sediment cores from the primary estuaries of Chaohu Lake, Eastern China. The results indicate that the OCP concentrations in the surface and core sediments around Chaohu Lake were 3.48–121.08 (with a mean of 34.93) ng/g and 0.60–39.28 (7.07) ng/g, respectively. Significantly higher concentrations of ΣOCPs were observed in sediment samples from the Nanfei River and its estuary. The three important OCP contributors around Chaohu Lake were dichlorodiphenyltrichloroethane and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), and hexachlorobenzene (HCB), which originated primarily from the historical use of technical DDTs and HCHs. A principal component analysis (PCA) suggests that HCB and lindane may originate from the same sources, and DDTs were greatly influenced by organic carbon from the soil environment and the impact of urbanization processes.     

Distribution and ecological risks of polychlorinated biphenyls (PCBs) in surface sediment of the Forcados River,Niger Delta,Nigeria

Concentrations of Σ15 PCBs in sediments of the Forcados River, Nigeria, were determined in 2012 to provide information on the profile, sources and ecotoxicological risks of PCBs in the sediment. The screening concentrations of PCBs were quantified using a gas chromatograph equipped with a Ni-63 electron capture detector. The concentrations of the Σ15 PCBs ranged from 2.7 to 202.3 µg kg???1 with a mean concentration of 46.5 µg kg???1. The composition of PCB congeners was clearly dominated by octa-PCBs, hepta-PCBs and hexa-PCBs, constituting 68.1% to 93.7%, respectively, of the total amounts of PCBs. All sites had Σ15 PCB levels below the prescribed probable effect concentrations, and therefore no adverse effects are expected for the majority of sediment-dwelling organisms of the Forcados River system.     

The importance of runoff to DDT and PCB inputs to the Sado estuary and Ria Formosa

PCB congeners, DDT and metabolites were determined in suspended sediments and in the oysterCrassostrea angulata from the upper Sado estuary over two years (1987/88 and 1990) and from Ria Formosa during 1990. Levels of DDT concentrations in suspended sediments collected in both estuarine areas, either in 1988 or 1990, increased in winter. Otherwise, PCB concentrations varied in an erratic way. A DDT enrichment was also recorded inC. angulata in winter and an increase of only PCB concentration levels in oysters of the upper Sado estuary was registered at the same period. These results suggest that, in the absence of important direct sources of PCB and DDT, runoff appears to be the major source of those compounds in both the study areas. Levels of concentrations of these pollutants in oysters reflect either their increase in the environment or changes in particle dynamics in the two estuarine areas.     

Growth of an estuarinePseudomonas sp. on polychlorinated biphenyl

In the course of a study of the microbial degradation of polychlorinated biphenyls (PCB), 16 cultures, representing 5 genera of bacteria, were isolated. APseudomonas sp. was found to degrade mixtures of PCB (Aroclor 1254) and pure isomers, i.e., hexachlorobiphenyl (HCB). Degradation was found to be variable, depending on length of incubation, purity, and degree of chlorination of the biphenyl molecule. In addition to apparent degradation of PCB, it was observed that PCB stimulated growth and oxygen uptake. Bioaccumulation of PCB residues was suggested since¹⁴-Clabeled material derived from¹⁴C-PCB accumulated on or in the bacterial cells. The potential degradation and utilization of PCB by microorganisms suggests that this may be an important mechanism for removal or mobilization of PCB into food chains in the estuarine environment.     

Coupling of bioaugmentation and phytoremediation to improve PCBs removal from a transformer oil-contaminated soil

This study was carried out to assess the dissipation of 17 selected polychlorinated biphenyl (PCB_i) congeners in a transformer oil-contaminated soil using bioaugmentation with 2 PCB-degrading bacterial strains, i.e., Pseudomonas spp. S5 and Alcaligenes faecalis, assisted or not by the maize (Zea mays L.) plantation. After 5 and 10 weeks of treatment, the remaining concentrations of the target PCB_i congeners in the soil were extracted and measured using GC-MS. Results showed that the bacterial augmentation treatments with Pseudomonas spp. S5 and A. faecalis led to 21.4% and 20.4% reduction in the total concentration of the target PCBs (ΣPCB_i), respectively, compared to non-bioaugmented unplanted control soil. The ΣPCB_i decreased by 35.8% in the non-bioaugmented planted soil compared with the control. The greatest degradation of the PCB congeners was observed over a 10-week period in the soil inoculated with Pseudomonas spp. S5 and cultivated with maize. Under this treatment, the ΣPCB_i decreased from 357 to 119 ng g^?1 (66.7% lower) and from 1091 to 520 ng g^?1 (52.3% lower). Overall, the results suggested that the combined application of phytoremediation and bioaugmentation was an effective technique to remove PCBs and remediate transformer oil-contaminated soils.     

Seasonal-spatial distributions,congener profile,and risk assessment of polychlorinated biphenyls (PCBS) in the surficial sediments from the coastal area of Bangladesh

A comprehensive congener specific assessment of polychlorinated biphenyls (PCBs) was conducted for the first time in Bangladesh. All 209 PCB congeners in the surficial coastal sediments from the coastal areas of Bangladesh were analyzed by GC-MS/MS. The total concentrations of PCBs (∑PCBs) varied from 5.27 to 92.21 and 4.61 to 105.3 ng/g dw in winter and summer, respectively, and the ranges were comparable to or higher than those recorded in the sediments from the coastal areas of India, Korea, China, and Taiwan. The seasonal difference in the levels of PCBs was not statistically significant (p > 0.05). The spatial distribution revealed that the areas with recent urbanization and industrialization (Chittagong, Cox’s Bazar and Sundarbans) were more contaminated with PCBs than the unindustrialized area (Meghna Estuary). Moderately chlorinated (4–6 Cl) homologs dominated PCB profiles. A set of congeners based on their detection frequencies and abundance were identified and categorized as potential environmental marker PCBs, which can be used for the future selective monitoring studies where there would be limitations on whole congener assessment. Ecotoxicologically, the sedimentary PCB concentrations exceeded some of the existing environmental quality standards, suggesting a potential threat to the aquatic organisms in the Bangladeshi coastal areas.     

太湖地区水稻土的健康质量问题及调控对策

从可持续生产安全、营养农产品角度 ,比较系统地阐述了土壤健康质量的概念和内涵 .同时根据土壤健康质量的概念 ,对太湖地区 13个省市级水稻丰产示范方及其灌溉河流淤泥进行了调查 .结果表明 ,太湖地区水稻土N、P含量相对较高 ,但引起面源污染的可能性较小 ,同样水稻土中的重金属含量基本上在环境背景值范围内 ,但点源污染不可忽视 .DDT和六六六的残留也在标准允许范围内 ,生命有益元素Se处于相对缺乏程度 .然而 ,由于乡镇企业的发展 ,三废的肆意排放 ,灌溉河流的富营养化及重金属污染极为严重 .部分河流淤泥中重金属Cu和Zn的含量分别高达 5 4和 7 2mg·kg-1.针对上述情况及发展趋势 ,提出了一些相应的主要控制措施 .     

Vergleich der Schadstoffbelastung in Eiern des Sperbers (Accipiter nisus) aus Brandenburg und Nordrhein-Westfalen, Deutschland

Zusammenfassung Eier von Sperbern aus Brandenburg und aus Nordhrein-Westfalen wurden auf ihren Gehalt an PCB, DDT, HCH, HCB und die Schwermetalle Blei und Cadmium untersucht. Bei den PCB und beim DDT und seinen Abbauprodukten traten signifikante Unterschiede in der Belastung der beiden Populationen auf, während die anderen untersuchten Stoffe in den Eiern beider Untersuchungsgebiete nur in geringen Mengen nachzuweisen waren. Dabei waren in den Proben aus der ehemaligen DDR die DDT-Konzentrationen deutlich höher als in den Eiern aus dem westfälischen Münsterland. Bei den PCB-Konzentrationen ergab sich ein genau umgekehrtes Ergebnis, im Münsterland waren diese erheblich höher. Die Ergebnisse stehen im klaren Zusammenhang mit der unterschiedlichen Anwendung und dem zeitlich unterschiedlich erfolgtem Verbot der untersuchten Schadstoffe in den beiden ehemaligen deutschen Staaten. Trotz der Belastungsunterschiede bezüglich der PCB ist das PCB-Muster in den Eiern aus den Untersuchungsgebieten aufgrund des artspezifischen Metabolismus nahezu identisch.

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Comparison between the burden of xenobiotics in eggs of the Sparrowhawk (Accipiter nisus) from Brandenburg and North-Rhine-Westphalia, Germany

Summary Eggs from Sparrowhawks from Brandenburg (former GDR) and North-Rhine-Westphalia (former FRG) were examined for their burden of PCB, DDT, HCH, HCB and the heavy metals lead and cadmium. Significant differences emerged in the cases of PCB and DDT and its metabolites between the populations of the two regions. The other examined xenobiotics were detectable only in low concentrations. The DDT concentrations were distinctly higher in the samples from the former GDR, while PCB concentrations were higher in the eggs from North-Rhine-Westphalia. The results reflect clearly the different use and prohibition of the examined xenobiotics in the two former german states. In spite of the differences in the PCB burden, the PCB pattern in the eggs of the different regions is nearly identical. Eggshell indices correlate negatively with DDT burden in both sample areas.

     

Anaerobic reductive dehalogenation of polychlorinated dioxins

Polychlorinated dibenzo-p-dioxins and -furans (PCDD/Fs) are among the most harmful environmental contaminants. Their widespread distribution due to unintentional or unknown release coincides with environmental persistence, acute and chronic toxicity to living organisms, and long-term effects due to the compounds’ tendency for bioaccumulation and biomagnification. While microbial aerobic degradation of PCDD/Fs is mainly reported for the turnover of low chlorinated congeners, this review focuses on anaerobic reductive dehalogenation, which may constitute a potential remediation strategy for polychlorinated compounds in soils and sediments. Microorganisms in sediments and in microcosms or enrichment cultures have been shown to be involved in the reductive dechlorination of dioxins. Bacteria related to the genus Dehalococcoides are capable of the reductive transformation of dioxins leading to lower chlorinated dioxins including di- and monochlorinated congeners. Thus, reductive dehalogenation might be one of the very few mechanisms able to mediate the turnover of polychlorinated dioxins by reducing their toxicity and paving the way for a subsequent breakdown of the carbon skeleton.     

Bioremediation of hexachlorocyclohexane (HCH) in soil using spent mushroom compost of Pleurotus ostreatus

Abstract

Hexachlorocyclohexane (HCH), a highly chlorinated pesticide, was used worldwide in the 1950s and 1960s. HCH toxic residues are still detected in environmental compartments. Thus, effective, viable and eco-friendly strategy is required for its remediation. In this study, degradation of four HCH isomers was evaluated by amending contaminated soil using four treatments of spent mushroom compost (SMC) of Pleurotus ostraetus. The soil was incubated for 5 weeks and was sampled every seven days. Quantitative attenuation in HCH was calculated using gas chromatography–electron capture detector (GC-ECD) and metabolite was identified using gas chromatography–mass selective detector (GC-MSD). Maximum reduction 58%, 26%, 45%, and 64% for α-, β-, γ- and δ-HCH isomers, respectively, using SMC and soil (both unsterilized) showed that this treatment was the best for bioremediation of HCH in soil. However, when one of the factors, either soil or SMC, was sterilized, a significant reduction in HCH degradation was noticed. The second most reduction of isomers was seen during treatment where unsterilized SMC was added in sterilized soil followed by treatment where SMC was sterilized but soil was not. Abiotic control did not remove any significant quantities of HCH. Simple first-order (SFO) kinetic confirmed that SMC reduced the half-live manifolds as compared to biotic control. Only one metabolite δ-PCCH was identified during the course of study.     

Polychlorinated biphenyls disrupt cell division and tip growth in two species of fucoid algae

Environmental contaminants, including poly‐chlorinated biphenyls (PCBs), are enriched in coastal sediments, and despite a 1977 moratorium by the United States Environmental Protection Agency on the production of PCBs, levels remain high, more so near former industrial plants. The effects of these contaminants on sessile species in the intertidal zone, particularly nonanimal species such as the ubiquitous fucoid brown algae, are not well known. We investigated the developmental effects of chronic PCB treatment beginning at fertilization on two species of marine rockweed, Fucus vesiculosus Linnaeus and Silvetia compressa (J.Agardh) E.Serrão, T.O.Cho, S.M.Boo & Brawley. A mixture of the most widely used PCB congeners, Aroclors 1221, 1242, and 1254, was delivered at concentrations well below levels found in contaminated sediments, and resulted in severely delayed mitosis and cytokinesis in both species. In F. vesiculosus, this delay was accompanied by abnormal spindle morphology. PCB treatment also dramatically slowed or arrested rhizoid growth after 2–4 d, and by 7 d F. vesiculosus embryos were dead; in contrast, polar secretion of adhesive, germination, and photopolar germination were not affected. The dramatic delay in the first cell division and reduction in tip growth within the first week of development are likely to compromise S. compressa's ability to reproduce and establish new generations. Thus, the data presented here suggest that PCBs still present in coastal sediments may be inhibiting recruitment in these species. Moreover, as sediment dredging causes temporary spikes in PCB concentrations, these kinds of bioremediation steps may exacerbate the disruption of fucoid development.     

In Vivo measurement of unscheduled DNA synthesis and S-phase synthesis as an indicator of hepatocarcinogenesis in rodents

Measurement of chemically induced DNA repair as unscheduled DNA synthesis in rodent liver following in vivo treatment is a useful screen for potential hepatocarcinogens. In addition to measurement of unscheduled DNA synthesis, examination of S-phase synthesis provides an indicator of chemically induced cell proliferation in the liver, which may be a basis for hepatic tumor promotion. Several chemicals and classes of chemicals have been examined using these endpoints. The pyrrolizidine alkaloid riddelline is a potent genotoxic agent in vitro, and in vivo studies confirm this response as riddelline induces significant elevations in unscheduled DNA synthesis and S-phase synthesis in rat liver. Conversely, H. C. Blue dyes #1 and #2 are both potent genotoxic agents in vitro but fail to express this genotoxicity in vivo. H. C Blue #1 induces significant increases in S-phase synthesis in B6C3F1 mouse liver, which correlates with the observed carcinogenicity of this compound. Halogenated hydrocarbons likewise fail to induce unscheduled DNA synthesis in vivo, but many of these compounds do increase hepatic cell proliferation in mice, which may be the principal mechanism of hepatocarcinogenesis in this species.Abbreviations BCMEE bis(2-chloro-l-methylethyl)ether - dThd thymidine - HCB1 H.C. Blue #1 - HCB2 H.C. Blue #2 - UDS unscheduled DNA synthesis     

Pseudomonas sp. to Sphingobium indicum: a journey of microbial degradation and bioremediation of Hexachlorocyclohexane

The unusual process of production of hexachlorocyclohexane (HCH) and extensive use of technical HCH and lindane has created a very serious problem of HCH contamination. While the use of technical HCH and lindane has been banned all over the world, India still continues producing lindane. Bacteria, especially Sphingomonads have been isolated that can degrade HCH isomers. Among all the bacterial strains isolated so far, Sphingobium indicum B90A that was isolated from HCH treated rhizosphere soil appears to have a better potential for HCH degradation. This conclusion is based on studies on the organization of lin genes and degradation ability of B90A. This strain perhaps can be used for HCH decontamination through bioaugmentation.