Distribution and Potential Human Risk of Organochlorine Pesticides in Market Mollusks from Dalian, China

Levels of organochlorine pesticides (OCPs) were analyzed in mollusk samples collected from markets in Dalian, China. Among 14 OCPs screened, chlordane (Chls), dichlorodiphenyltrichloroethane (DDT) and 1,2,3,4,5,6-hexachlorocyclohexane (HCH) were dominant compounds with the medians of 30.2, 5.31 and 2.03 ng/g wet weight (ww), respectively. Source analysis showed that, much higher concentrations of Chls in mollusk samples were the result of usage of the chemical in the city, HCH in samples were mainly due to historical technical HCH usage, and a small amount of fresh use of DDT might exist, causing high portion of p,p′-DDT in samples. Cumulative distribution functions for the concentrations of the selected OCPs were compared to several threshold criteria, indicating that concentrations in most mollusk samples were lower than the safe lines. The concentration data of selected OCPs were used for risk assessment, and human exposure levels were compared to noncancer and cancer benchmarks.     

Levels of Organochlorine Pesticides in Crops and Related Products From Vojvodina,Serbia: Estimated Dietary Intake

Levels of 16 organochlorine pesticides (OCPs) were investigated in 39 composite samples of agricultural crops, related by-products, and foodstuffs collected in Vojvodina, Serbia, in 2002 through 2004. After extraction and cleanup, OCPs were determined by capillary gas chromatography using electron-capture detection. The highest mean level of 0.971 ng/g whole weight (ww) was found for α-HCH in wheat flour samples. OCPs levels were well lower than the respective maximum residue limits set by current European and Serbian regulations. Mean OCP levels were low (<1 ng/g ww) for all sample types. The most frequently determined residue was 4,4′-DDT (identified in 76.9% of all samples analyzed), followed by γ-HCH (66.7%), β-HCH (48.7%), and endosulfan II (41.0%). OCP levels were compared with data from other international surveys. Calculated daily intakes of OCPs by way of consumption of the crop products included in this study according to data of the Serbian National Institute for Statistics were compared with the acceptable daily intakes established by the Food and Agriculture Organization/World Health Organization. The average level of contamination of the Vojvodina diet was believed to be harmless regarding the studied food commodities.     

Freshwater Fish–Consumption Relations With Total Hair Mercury and Selenium Among Women in Eastern China

Wild fish from Qiandao Hu, a reservoir in the Zhejiang Province in eastern China, have increased mercury (Hg) concentrations exceeding the World Health Organization’s (WHO) recommended guidelines. Due to the importance of freshwater biota in the local cuisine, dietary exposure to increased neurotoxic Hg is a concern in this region. An environmental hair-marker study was undertaken coincident with a cross-sectional epidemiologic study with 50 women age 17–46 years living in a Qiandao Hu fishing village. Diet, occupation, and other possible sources of Hg were recorded by way of questionnaires. Total mercury (THg) and selenium (Se) concentrations were measured in human hair samples and in important market fish species. Fish THg and Se concentrations were increased, with some fish concentrations >200 ng/g THg and 500 ng/g Se (wet weight [ww]). However, the average hair THg was low at 0.76 ± 0.51 μg/g dry weight, lower than the WHO’s no observable–adverse effect level (50 μg/g), whereas the average hair Se was 1.0 μg/g. Hair THg concentration was positively associated with the average mass of fish consumed weekly, indicating that fish consumption is the main contributor to hair THg in this geographic area. The age-related hair THg trend was not linear but instead demonstrated a rapid increase in THg before age 25 years, followed by consistent concentrations in all ages after age 25 years. There was a positive correlation (p < 0.001) between molar Se and Hg in the hair samples, suggesting a possible antagonistic relation. This is the first study examining the relation between dietary Hg exposure and hair THg in an eastern China community where freshwater fish, as opposed to marine fish, dominates the cuisine.     

Residues of Organochlorine Pesticides in Fish from the Gomti River,India

This study reports the levels and distribution patterns of some organochlorine pesticides (OCPs) in fish samples of the Gomti river, India, collected from three sites. In the fish muscles ∑OCPs ranged between 2.58–22.56 ng g⁻¹ (mean value: 9.66 ± 5.60 ng g⁻¹). Neither spatial nor temporal trends could be observed in distribution of the OCPs. Aldrin was the predominant OCP, whereas, HCB and methoxychlor could not be detected. α-HCH and β-HCH among the isomers of HCH and pp-DDE among the metabolites of DDT were the most frequently detected OCPs. The results revealed that the fish of the Gomti river are contaminated with various OCPs.     

Concentrations and Accumulation Features of Organochlorine Pesticides in the Baiyangdian Lake Freshwater Food Web of North China

Organochlorine pesticides (OCPs), such as hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT), are ubiquitous anthropogenic environmental contaminants. They are persistent, broad-spectrum toxicants that accumulate in the food web with potential risks to the ecosystem and human health. HCHs were the predominant contaminants in Baiyangdian Lake, North China. Concentrations of HCHs and DDTs ranged from 58 to 563 ng/g lipid weight (lw) and 21 to 401 ng/g lw, respectively, for aquatic biota samples. The highest levels of HCHs and DDTs were observed in muscles of yellow catfish. The mean concentrations of OCPs were 4.6 ng/L for water, 95 ng/g dry weight (dw) for aquatic plants, and 14 ng/g dw for sediments. Among the isomers and metabolites, α-HCH and p,p′-1,1-di(p-chlorophenyl)-2,2-dichloroethylene (p,p′-DDE) were the predominant congeners in biota samples. Correlations between log lipid-normalized concentrations of HCHs and DDTs and trophic levels (TLs) based on analysis of stable isotopes of nitrogen confirmed that persistent organic pollutants were magnified in the Baiyangdian Lake food web. Significant positive relationships were found for α-HCH and p,p′-DDT and their trophic magnification factors, which were 1.6 and 1.7, respectively. These results provide evidence of biomagnification of persistent organic pollutants (POPs) in freshwater food webs.     

Assessment and Investigation on the Fate of Organochlorine Pesticides in Water and Sediments of International Amir-kalaye Wetland in North of Iran

A total of 48 water samples and 24 sediment samples were collected at four sampling stations along the wetland during four seasons from 2009 to 2010 and analyzed by gas chromatograph–electron capture detector (GC–ECD). In water the total concentration of OCPs was 0.33, 0.01, 0.1 and 0.07 mg/L in summer, autumn, winter and spring, respectively. The most frequent OCP compounds detected were endrin and chlordane (0.08 and 0.07 mg/L), heaxachlorobenzene and chlordane (0.06, 0.02 mg/L), and chlordane (0.07 mg/L) in summer, winter and spring, respectively. The maximum concentration of ΣOCPs was found in samples collected from station 1 in summer (0.26 mg/L). In sediments the total concentrations of OCPs were 15.84 and 2.62 mg/g-dry weight (dw) in summer and winter, respectively. Chlordane was the most frequently found OCP compound, followed by lindane, 9.92 and 2.47 mg/g-dry weight (dw), respectively, in summer. While, lindane (2.52 mg/g-dw) and endosulfan I (0.1 mg/g-dw) were the highest OCP compounds detected in winter. The results obtained in this study show that there still exist a variety of organochlorine pesticide residues in the water and sediments from the Amir-kalaye wetland in Iran.     

Organochlorine Pesticide Residues in Inland Wetland Fishes of Karnataka, India and Their Implications on Human Dietary Intake

As part of a larger study assessing contamination status of inland wetlands of India, we evaluated the organochlorine pesticide (OCP) residues in fishes collected from different inland wetlands in Karnataka, India and their suitability for human consumption. Among the OCPs tested, isomers of hexachlorocyclohexane (HCH) were the most frequently detected with β- and γ-HCH as the main pollutants. Average concentration of ∑HCH and ∑DDT ranged from 2.1 to 51.7 μg/kg and below detection level to 12.3 μg/kg respectively. Other organochlorine pesticides such as heptachlor epoxide, dieldrin and endosulphan were found at lower levels. Among various fish species tested, the higher pesticide burden was recorded in Anguilla bicolor bicolour (77.9 μg/kg) and the lower was in Heteropneustes fossilis (2.1 μg/kg). OCPs detected in the present study were well below the tolerance limits recommended for fishes. The calculated daily dietary intake of OCPs in all the species examined was lower than the maximum acceptable dietary intake (ADI) limits prescribed for human consumption. However, continuous monitoring is recommended to facilitate the early identification of risks.     

Seasonal Trends and Tissue Distribution of Organochlorine Pollutants in Wild and Farmed Gilthead Sea Bream (<Emphasis Type="Italic">Sparus aurata</Emphasis>) from the Western Mediterranean Sea and Their Relationship with Environmental and Biological Factors

Seasonal trends and tissue distribution of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in gilthead sea bream (Sparus aurata) samples from the Western Mediterranean were investigated. Hexane extracts of white and red muscle, liver, and gills from wild and cultured specimens were purified by normal-phase high-performance liquid chromatography, and selected OCPs and PCBs were determined by gas chromatography coupled to mass spectrometry as indicators of contamination. The limits of detection for the analytical methodology allowed was 0.25 ng/g. Data obtained showed the presence of DDTs and PCBs in the different tissues, with the highest concentration of pollutants being in tissues of higher lipid content. Concentrations of organochlorine compounds in sea bream tissues strongly correlated with seasonal changes and the biological cycle of the species. In general, cultured fish had lower concentrations of contaminants and smaller season variability than wild fish. Trace levels of contaminants were found in fish muscle throughout the year, but always below the guidelines recommended for human consumption.     

Flesh residue concentrations of organochlorine pesticides in farmed and wild salmon from British Columbia, Canada

The present study reports measured levels of organochlorine pesticides (OCPs) in commercial salmon feed (n?=?8) and farmed Atlantic, coho, and chinook salmon (n?=?110), as well as wild coho, chinook, chum, sockeye, and pink salmon (n?=?91). Flesh residue concentrations (ng/g wet weight) of dichlorodiphenyltrichloroethanes (DDTs), hexachlorocyclohexanes (HCHs), chlordanes, chlorobenzenes (CBz) and cyclodiene pesticides (e.g., dieldrin, mirex) were 2 to 11 times higher (p??10?). Surprisingly, less hydrophobic pesticides such as hexachlorocyclohexanes and endosulfans (K(OW) s??5). This is contrary to previous laboratory and field observations demonstrating fish BMFs less than 1 for low K(OW) chemicals, because of efficient respiratory elimination of those compounds via gills. The results suggest that ambient seawater concentrations and bioconcentration-driven accumulation may play a key role in the bioaccumulation of these relatively more water-soluble contaminants in farmed salmon. Finally, OCP exposure through consumption of British Columbian salmon is found to be low relative to United States national average per capita total exposure levels and provisional tolerable daily intakes.     

Vertical Fluxes and Accumulation of Organochlorine Pesticides in Sediments of Haihe River,Tianjin, China

Organochlorine pesticides (OCPs) concentrations in sediments and sediment trap fluxes of particulate organic carbon and OCPs were measured from October 2006 to May 2008 in the urban reach of Haihe River, Tianjin, China, in order to investigate vertical fluxes and accumulation of OCPs in sediments. The concentrations of OCPs in sediments (dry weight basis) were in the range of 2.08–10.07 ng/g (mean 4.70 ng/g) for HCHs (α-, β-, γ-, δ-HCH), 5.82–43.39 ng/g (mean 17.43 ng/g) for DDTs (p,p′-DDE, p,p′-DDD, o,p′-DDT, p,p′-DDT). Compared with data reported in Haihe River 2003, the levels of OCPs showed a significant decrease between 2003 and 2008. This is mainly attributed to significant decrease of production and usage of HCHs and DDTs and biodegradation of HCHs and DDTs in sediment. Concentrations of HCHs and DDTs in sediments were well correlated with sediment organic carbon contents. Concentrations of OCPs in settling particles (dry weight basis) ranged from 21.2 to 138.4 ng/g (mean 52.6 ng/g) for HCHs, 30.0–245.7 ng/g (mean 87.1 ng/g) for DDTs, which were 2.2–48.2-fold higher than those associated with sediments. β-HCH was the dominant HCH isomer in both sediments and settling particles. Among DDTs, p,p′-DDE was found to be dominant in sediments, while p,p′-DDT was the predominant form in settling particles. This suggests that further biodegradation of OCPs occurred during the course of sedimentation and burial. The annual sediment trap flux of OCPs in Haihe River in the urban area of Tianjin was 177–211 μg/m² yr for HCHs and 213–341 μg/m² yr for DDTs, respectively.     

Deposition of Organochlorine Pesticides,PCBs (Aroclor 1268), and PBDEs in Selected Plant Species from a Superfund Site at Brunswick,Georgia, USA

Deposition of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were measured in Loblolly pine needles (Pinus taeda) collected in and around a Linden Chemicals and Plastics (LCP) Superfund Site at Brunswick, Georgia, USA. For the comparison, foliage of eastern red cedar (Juniperus virginiana) was also collected to monitor contaminant levels. This study revealed that concentrations of OCPs, PCBs and PBDEs ranged from 0.75–10, 3.4–15 to 0.05–3, ng/g wet wt, respectively in both plant species. Total OCPs concentrations in pine needles decreased from 10 to 2.3 ng/g; and total PCBs decreased from 28 to 9.3 ng/g between 1997 and 2006. To our knowledge, this is the first report on PBDEs concentrations in pine needles and red cedar foliage samples from the Superfund Site at Brunswick, Georgia, USA.     

Comparison of the uptake of polycyclic aromatic hydrocarbons and organochlorine pesticides by semipermeable membrane devices and caged fish (Carassius carassius) in Taihu Lake, China

Uptake of polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) by triolein-containing semipermeable membrane devices (SPMDs) and by crucian carp (Carassius carassius) was studied in Taihu Lake, a shallow, freshwater lake in China. Crucian carp and SPMDs were deployed side by side for 32 d. The first-order uptake rate constants of individual PAHs and OCPs for the two matrices were calculated and compared to relate the amounts of chemicals accumulated by the matrices to dissolved water concentrations. On a wet-weight basis, total concentrations of PAHs and OCPs in crucian carp fillets averaged 49.5 and 13.6 ng/g, respectively, after the 32-d exposure, whereas concentrations in whole SPMDs averaged 716.9 and 62.3 ng/g, respectively. The uptake rate constants of PAHs and OCPs by SPMDs averaged seven- and fivefold higher, respectively, than those for crucian carp; however, the patterns of uptake rate constants derived from test chemical concentrations in the crucian carp and SPMDs were similar. Although equilibrium was not reached for some PAHs and OCPs during the 32-d exposure period, a reasonably good correlation between the concentration factors (CFs) and octanol/water partition coefficient (Kow) values of PAHs and OCPs in SPMDs (r = 0.86, p < 0.001) was observed when potential sorption to dissolved organic carbon was taken into account. Similar efforts to correlate the CFs and Kow values of PAHs and OCPs in crucian carp (r = 0.75, p < 0.001) were less successful, likely because of PAH metabolism by finfish. Overall, the present results suggest that SPMDs may serve as a surrogate for contaminant monitoring with fish in freshwater lake environments.     

Organochlorine Contamination in Anuran Amphibians of an Artificial Lake in the Semiarid Midwest of Argentina

Artificial water reservoirs are important for fauna in arid-semiarid regions, because they provide suitable habitats for species that depend on water, such as amphibians. Organochlorine pesticides (OCPs) are toxic, persistent compounds that tend to bioaccumulate and bioconcentrate. We evaluated contaminant levels in anurans from an artificial lake (Embalse La Florida) in a semiarid region of the Midwest Argentina. This lake is one of the few sources of permanent water in the area. OCPs were detected in all individuals. Levels ranged from 2.34 ± 0.62 ng/g wet mass of heptachlors to 9.76 ± 1.76 ng/g wet mass of hexachlorocyclohexanes. The distribution pattern of OCP was ∑HCH > ∑DDT > endosulfan > ∑chlordane > metoxichlor > ∑aldrin > ∑heptachlor. Contaminant levels in individuals were positively correlated with contaminant levels in the water. Burden differed between species, but not among sites differing in water contaminant levels. Results suggest that anurans may concentrate OCPs and thus provide an important source of exposure for amphibian predators. This study provides important information for potential risk assessment of amphibians in the region and contributes to our understanding of the extent of OCP contamination.     

Organochlorine Pesticide Residues in Eggs and Tissues of House Sparrow, <Emphasis Type="Italic">Passer domesticus,</Emphasis> from Tamil Nadu,India

This study provides information on the current status of contamination by organochlorine pesticides (OCPs) in eggs and tissues of House Sparrow, Passer domesticus, in Tamil Nadu, India. The mean concentration of total hexachlorocyclohexane (∑HCH) and total dichloro-diphenyl-trichloroethane (∑DDT) in eggs ranged from 0.01 to 1.81 μg/g and 0.02 to 1.29 μg/g, respectively. Concentration of 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p′-DDE) ranged from below detectable limit (BDL) to 0.64 μg/g, representing more than 60% of the ∑DDTs. About 28% of samples had p,p′-DDE levels above the critical concentration associated with reproductive impairment. However, the mean concentrations of cyclodiene insecticides were less than 0.5 μg/g. Although OCPs levels detected in tissues are not indicative of toxicity, continuous monitoring is recommended.     

Endocrine-Disrupting Organochlorine Pesticides in Human Breast Milk: Changes during Lactation

The aim of the present study was to assess infant safety associated with the occurrence of endocrine-disrupting organochlorine pesticides (OCP) in breast milk. Moreover, the association between pregnant mothers’ dietary habits and these compounds levels in breast milk was investigated. Breast milk was collected at various stages of lactation. The samples were analyzed by the GC-MS method. The OCP concentrations ranged from < limit of detection (LOD) to 6.81 ng/g lipids. The highest OCP concentrations in breast milk occurred primarily within the first month of lactation, and decreased over the lactation period. It was found that the maternal consumption of certain food products—in particular pork, beef, poultry, eggs, and dairy products—could have affected the content of 1,1’-(2,2,2-Trichloroethane-1,1-diyl)bis(4-chlorobenzene), called DDT and its metabolites in the breast milk. The levels of beta-endosulfan were positively correlated with fish and poultry consumption. The redundancy analysis indicated that the diets of the pregnant women had an important impact on pesticide residues in the breast milk. There is a potential possibility of lowering the content of organochlorine compounds in breast milk by adhering to nutritional recommendations, e.g., avoiding the excessive consumption of fish and other raw food materials of unknown origin.     

Levels of Organochlorine Pesticide Residues in Blood Plasma of Various Species of Birds from India

Concentrations of organochlorine pesticides (OCPs) were measured in blood plasma of 13 species of birds collected from Ahmedabad, India. Among the various OCPs determined, HCHs and its isomers had higher contribution to the total OCPs. Concentration of ∑HCHs varied from 11.4 ng/mL in White ibis Threskiornis melanocephalus to 286 ng/mL in Sarus Crane Grus antigone, while ∑DDT ranged between 19 ng/mL in Black Ibis Pseudibis papillosa and 147 ng/mL in Painted Stork Mycteria leucocephala. p,p′-DDE was accounted for more than 50% of total DDT in many of the samples analysed. However, a p,p′-DDT to p,p′-DDE ratio higher than one obtained for many species of birds indicates the recent use of DDT in this study region. The concentrations of cyclodiene insecticides, heptachlor epoxide, dieldrin and total endosulfan ranged from 15.8 to 296.2 ng/mL, below detectable level to 15 and 41.1–153.2 ng/mL, respectively. The pattern of total OCP load generally occurred in the following order: granivores < insectivores < omnivores < piscivores < carnivores. Although, the organochlorine residues detected in blood plasma of birds are not indicative of toxicity, the presence of residues in birds over the years (2005–2007) indicates continued exposure to organochlorine compounds. However, continuous monitoring is recommended to facilitate the early identification of risks to the survival of a species.     

Occurrence and Distribution of Persistent Trace Organics in Rainwater in an Urban Region (India)

The rainwater samples collected from the Lucknow city (India) were analyzed for selected organochlorine pesticides (OCPs) and polycyclic aromatic hydrocarbons (PAHs). HCH-isomers contributed most to the ΣOCPs with the highest levels of β-HCH isomer. The OCPs, which are currently banned in the country, were also observed. The residue levels of ΣOCPs in rainwater samples ranged between BDL and 447.17 ng L⁻¹. Endrin, β-endosulfan, heptachlor epoxide B and methoxychlor could not be detected in any of the sample. The levels of ΣPAHs in rainwater samples ranged between 19.32 and 11,112.09 ng L⁻¹ and the most abundant hydrocarbon was acenaphthylene. Further, the lower molecular weight PAHs dominated over the high molecular weight compounds.     

Persistent organic pollutants in muscle and feather of ten avian species from Māzandarān Province of Iran, on the coast of the Caspian Sea

Feather and muscle of 10 avian species (n = 46), were analyzed for polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs). Muscle contained significantly higher PCB and OCP than liver and feather. Mean muscle and feather PCB was 408.5 ± 134.5 and 32 ± 4.5 ng/g wet weight. Highly chlorinated PCBs were found in muscle and liver while feather had PCBs with less chlorination. Gulls had highest levels of both pollutants. Gull feather PCB and OCP were strongly correlated with their levels in the liver and muscle tissues (0.6 < r < 0.9, p < 0.01). Analysis of gull feather can be used as a non-invasive method for monitoring organic pollutants.     

Organochlorine pesticides in seafood products from southern China and health risk assessment

Seafood consumption is an important route of human exposure to organic contaminants. Residual levels of organochlorine pesticides (OCPs), including DDTs, hexachlorocyclohexanes (HCHs), heptachlor, aldrin, alpha-endosulfan, beta-endosulfan, dieldrin, endrin, endrin aldehyde, endrin ketone, methoxychlor, endosulfan sulfate, and heptachlor epoxide, were determined in a wide variety of seafood products collected from 11 coastal cities in southern China in June and October 2005. The results indicated that OCPs were predominated by DDTs and HCHs. The concentrations of other OCP components generally were low and were detectable in a small number of seafood samples only, probably reflective of the generally low levels of these OCPs in the study region and low bioaccumulation potentials in the species under investigation. Risk assessment against various standards clearly showed that seafood products were highly contaminated by DDTs and may pose health threat to local residents and the consumers all over the world. Furthermore, other OCP components, such as dieldrin and heptachlor, also impose lifetime cancer risk, especially to residents of coastal regions who often consume more seafood than those living inland. Therefore, continual monitoring of OCPs in various environment compartments, including biota and abiota, urgently is needed to mitigate effectively the impact of OCPs, particularly DDTs, on human health and the ecological environment.