Organochlorine Levels Research Articles

Factors Associated with Maternal Serum Levels of Perfluoroalkyl Substances and Organochlorines: A Descriptive Study of Parous Women in Norway and Sweden.

IntroductionPerfluoroalkyl substances (PFASs) and organochlorines (OCs) are ubiquitous and persistent in the environment and proposed endocrine disrupting chemicals (EDCs). They can be transferred across the placenta during pregnancy, and studies suggest that the prenatal period may be particularly sensitive for influences on fetal growth and development. Several studies have investigated socio-demographic and pregnancy related factors associated with maternal serum PFAS and OC levels, but few studies have been conducted in time periods with increasing emissions of PFASs and recent emissions of OCs.MethodsSerum from 424 pregnant women participating in the NICHD Scandinavian Successive Small-for-gestational Age (SGA) births study was collected in 1986–1988, and analyses of two PFASs and six OCs were conducted. Associations between EDCs and geographic, time dependent, socio-demographic and pregnancy related variables were evaluated by using multivariable linear regression models.ResultsPrevious breastfeeding duration, time since last breastfeeding period, sampling date and country of residence were important factors associated with serum levels of PFOS and PFOA. Smoking status and pre-pregnancy BMI were negatively associated with PFOS, and maternal height was borderline negatively associated with PFOS and PFOA. Glomerular filtration rate (GFR) was negatively associated with PFOS in a sub-sample. Maternal serum levels of OCs were positively associated with maternal age, and negatively associated with previous breastfeeding duration and sampling date. Smoking had a consistently negative association with PCB 118 in a dose-dependent manner. Education level, pre-pregnancy BMI and alcohol consumption varied in importance according to the compound under study.ConclusionsSeveral maternal factors, including potentially modifiable factors, markers of pregnancy physiology and factors also related to perinatal outcomes were associated with EDC levels. Results from this study are relevant to populations with still high PFAS and OC levels, i.e. developing countries. Moreover, we can use this knowledge about associated factors on emerging EDCs with similar properties.

Pesticide residues in water, sediment and fish from Tono Reservoir and their health risk implications.

Levels of organochlorine (OC) and organophosphorus (OP) pesticide residues in fish, sediments and water and their health risk associated with the consumption of the fish from the Tono Reservoir, Ghana were evaluated. The analytical methods included solvent extraction of the pesticide residues using ultrasound sonication and soxhlet extraction and their subsequent quantification using GC equipped with electron capture detector and pulse flame photometric detector after clean-up on activated silica gel/anhydrous sodium sulphate. A total of 29 pesticides comprising 16 OCs and 13 OPs were analyzed, out of which aldrin, p,p′-DDE and p,p′-DDD were detected in fish and sediment samples. The results showed that all the residues in water had their concentrations below the detection limit. Mean concentrations of organochlorine pesticide (OCP) residues in fish ranged from 0.017 to 0.17, 0.043 to 0.30, 0.027 to 0.243 and 0.097 to 0.263 µg/g in Sarotherodon galilaeus, Clarias anguillaris, Schilbe intermedius and Marcusenius senegalensis respectively. Mean concentrations of organophosphates pesticides ranged from 0.080 to 0.090, 0.080 to 0.087 and 0.050 to 0.063 µg/g in C. anguillaris, S. intermedius and M. senegalensis respectively. The level of chlorpyrifos in S. galilaeus was 0.160 µg/g. Mean concentrations of OCP residue in sediments ranged from 0.047 to 0.090 µg/g. Aldrin recorded the highest level while p,p′-DDD recorded the lowest level. The mean concentrations for all the detected residues were below the WHO/FAO maximum residue limits. Health risk estimation revealed that aldrin in M. senegalensis had great potential for systemic toxicity to consumers.

Maternal serum levels of perfluoroalkyl substances and organochlorines and indices of fetal growth: a Scandinavian case\u2013cohort study

Background:The associations between prenatal exposure to endocrine disruptive chemicals (EDCs) and fetal growth are inconsistent, and few studies have considered small-for-gestational-age (SGA) birth as an outcome. Our current study of Scandinavian parous women aimed to address these inconsistencies and gaps in the literature.Methods:This case–cohort study included 424 mother–child pairs who participated in a prospective, multi-center study of parous women in Norway (Trondheim and Bergen) and Sweden (Uppsala). We used linear and logistic regression with 95% confidence intervals (CIs) to analyze the associations between two perfluoroalkyl substances (PFASs) and five organochlorines (OCs) from early second trimester and indices of fetal growth.Results:Among Swedish women, prenatal exposure to perfluorooctanoate (PFOA), polychlorinated biphenyl (PCB) 153 and hexachlorobenzene (HCB) were associated with higher odds for SGA birth. We found stronger associations among Swedish male offspring. In the Norwegian cohort, we found no significant associations between EDC exposure and indices of fetal growth.Conclusions:Some populations may be more vulnerable to EDCs, possibly due to differences in exposure levels, exposure sources and/or modifiable lifestyle factors. Male offspring may be more vulnerable to endocrine disruption.

Endocrine disrupting chemicals and ovulation: Is there a relationship?

Although the potential for endocrine disrupting chemicals (EDCs) to disrupt female fecundity is great, few studies have assessed the threat to human reproduction. This study investigates levels of organochlorines in relation to their impact on women’s menstrual cycles and ovulatory status.To address concerns of the Akwesasne Mohawk community in upstate New York regarding well-established exposure to EDCs, women’s fertility and reproductive health endpoints, we recruited 215 women between the ages of 21 and 38 years to measure menstrual cycle characteristics and levels of local pollutants. Of these, 155 women collected saliva over the course of their menstrual cycle allowing for analysis of estradiol and progesterone levels and the determination of ovulatory status in relationship to their serum pollutant levels. A subset of participants (15) who did not commence cycling within a month of their enrollment were not included in the analysis, hence reducing the sample size to 140 participants. Additionally, a lipid panel, estradiol and progesterone were assessed in serum on Day 3 of the menstrual cycle.Median cycle length for women in the sample was 29 days. After aligning the cycles, 110 women were considered ovulatory and 45 (29%) anovulatory. Concentrations of groups of more persistent PCBs congeners, HCB, and p,p’-DDE did not differ significantly with ovulatory status. However, a sub-group of low-chlorinated PCB congeners, considered to be estrogenic were significantly higher among anovulatory women. These findings suggest that certain EDC’s, ubiquitous in our environment, may adversely affect menstrual cycles and thus have the capacity to impair reproductive function, including likelihood of conception.

Organochlorine levels in plasma and risk of multiple myeloma

Introduction: Multiple myeloma (MM) is a relatively rare cancer and little is known about its causes. Plasma levels of polychlorinated biphenyls (PCB) and organochlorine pesticides have been associated with increased risks of non-Hodgkin lymphoma and cutaneous malignant melanoma. There is very limited information regarding the association between these chemicals and the risk of MM, however, there is some evidence of an increased risk of MM in farmers related to exposure to organochlorine insecticides. The aim of this study is to investigate the association between plasma organochlorine levels and the risk of MM. Methods: A population-based case-control study was conducted in British Columbia (BC), Canada between 2009 and 2013. Cases were identified and recruited through the BC Cancer Registry, while age-group and sex-matched controls were randomly selected from the Consolidation File of the British Columbia Ministry of Health which contains identifying information on all participants in the population-based health insurance plan. 334 cases and 331 controls completed a computer-assisted telephone interview about environmental, lifestyle and medical factors, and provided a blood sample from which lipid adjusted levels of 14 congeners of PCB and 11 pesticides or pesticide metabolites were measured at the Centre de Toxicologie du Quebec. Initial analysis compared median analyte levels between cases and controls. Significance was assessed by the Mann-Whitney test. Results: MM cases had significantly higher levels of six PCB congeners and six pesticide analytes compared to controls. Conclusions: These initial suggest the possibility of an increased risk of MM with increased exposure to organochlorines. In order to confirm the associations, logistic regression models will be used to estimate the association between and the risk of MM adjusted for potential confounding factors including age, sex, education, BMI and weight loss.

Pre-diagnostic Serum Concentrations of Organochlorines and Risk of Myeloid Leukemia: a Nested Case-Control Study in the Norwegian Janus Serum Bank Cohort

Introduction: Organochlorines (OCs) are structurally diverse and environmentally persistent chemicals that are widespread contaminants. Some OC pesticides and polychlorinated biphenyl (PCBs) congeners have been associated with lymphoid neoplasms. While an association between OC exposure and risk of myeloid leukemia (ML) is biologically plausible and suggestive based on observations in occupationally exposed individuals, associations between serum levels of OCs and risk of ML in the general population have not been evaluated prospectively. Methods: We conducted a nested case-control study within the Janus cohort, a population-based biobank consisting of serum samples collected in the time period 1972-2004 from ~318,000 individuals in Norway. Risk of ML in relation to lipid-adjusted levels of 11 OC pesticide metabolites and 34 PCB congeners was evaluated in 76 ML cases and 353 controls. Odds ratios (ORs) and 95% confidence intervals (CI) were computed and associations were adjusted for sex, county, age and date at blood draw, smoking, and BMI. Results: Higher levels of total chlordane/heptachlor metabolites were associated with future risk of ML in continuous (OR = 1.2, 95% CI = 1.0-1.5 per unit increase in the log-transformed concentration (ng/g lipid)) and tertile analyses (3rd vs. 1st tertile OR = 2.0, 95% CI = 0.9-4.6). The association was strongest for oxychlordane (OR = 1.9, 95% CI = 1.2-2.9 per unit increase in the log-transformed concentration (ng/g lipid); 3rd vs. 1st tertile OR = 2.2, 95% CI = 1.0-4.9), and a suggestive association with ML risk was also observed for higher levels of heptachlor epoxide (3rd vs. 1st tertile OR = 2.0, 95% CI = 0.9-4.5). No consistent associations with ML risk were observed for other OC pesticide metabolites or for PCBs. Conclusions: Our data provide evidence that metabolites of chlordane/heptachlor may be associated with future risk of ML. Studies with a larger number of ML cases are needed to follow-up on these findings.

POPs in the South Latin America: Bioaccumulation of DDT, PCB, HCB, HCH and Mirex in blubber of common dolphin (Delphinus delphis) and Fraser's dolphin (Lagenodelphis hosei) from Argentina

Organic compounds, in particular organochlorines, are highly persistent compounds which accumulate in biotic and abiotic substrates. Marine mammals bioaccumulate and biomagnify persistent organic pollutants (POPs) through diet. ∑PCB (26 PCB congeners), ∑DDT (pp-DDT, pp-DDD, pp-DDE), ∑HCH (α-HCH, β-HCH, γ-HCH, δ-HCH), HCB and mirex were analyzed from samples of subcutaneous adipose tissue of common dolphins, Delphinus delphis, and Fraser's dolphins, Lagenodelphis hosei, obtained in 1999 and 2012. The aim of this study was to determine the concentrations of POPs to get baseline information on the current state of pollution by these compounds in these two species in South Atlantic. At the same time, to assess concentrations of POPs in relation to age, the total length and sexual maturity in common dolphins. Organochlorine pesticides dominated Fraser's dolphins, DDT being the most abundant, while PCBs were mostly present in common dolphins. In both species, the distributions of isomers or metabolites followed the order: β-HCH>δ-HCH>γ-HCH>α-HCH and pp-DDE>pp-DDD>pp-DDT. As for ∑PCB, the largest contribution was given by congeners of high molecular weight, particularly by hexa and hepta - CBs. Common dolphins did not show effects on sexual maturity, age and standard length in the concentration of organochlorines. The mean concentrations found in this study are lower compared to those reported in other studies performed in dolphins elsewhere. This study provides new information regarding levels of organochlorines in common dolphins for the Southwestern Atlantic.

Use of feathers to assess polychlorinated biphenyl and organochlorine pesticide exposure in top predatory bird species of Pakistan

Little is known about the levels of organochlorines (OCs) in predatory bird species from Asia or the factors governing their concentrations. This study is the first report on concentrations of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in predatory birds of Pakistan. The concentrations of PCBs and OCPs were investigated using tail feathers of ten different species of predatory birds. In addition, concentration differences among body, tail, primary and secondary feathers were investigated for six individuals of black kite (Milvus migrans). Ranges of concentrations were highest for dichlorodiphenyldichloroethylene (p,p′-DDE: 0.11–2163ngg−1 dry wt.) followed by dichlorodiphenyltrichloroethane (p,p′-DDT: 0.36–345ngg−1 dry wt.), hexachlorobenzene (HCB: 0.02–34ngg−1 dry wt.), ∑PCBs (0.03–16ngg−1 dry wt.) and trans-nonachlor (TN; 0.01–0.13ngg−1 dry wt.). CB 118, 153, 138, and 180 along with p,p′-DDE were found as the most prevalent compounds. ∑PCBs and ∑DDTs were significantly different among species (both p<0.01) and omnivorous, scavengers, carnivorous and piscivorous trophic guilds (all p<0.03). Only ∑PCBs were significantly differentamong different families of birds (p<0.01). Values of stable isotopes (δ13C and δ15N) differed significantly (all p<0.01) among species, families, trophic guilds as well as terrestrial and aquatic habitat but not between nocturnal and diurnal predators (p=0.22 for δ13C; p=0.50 for δ15N). Concentrations of ∑PCBs, ∑DDTs and trans-nonachlor, but not HCB (p=0.86), were significantly different among different feather types (all p<0.01). Trophic and taxonomic affiliation as well as dietary carbon sources (δ13C) for species were identified as the variables best explaining the observed variation in exposure to the studied compounds. The significance of contributing factors responsible for OC contamination differences in predatory birds should be further elucidated in future studies.

Persistent organic pollutants in blood samples of Southern Giant Petrels (Macronectes giganteus) from the South Shetland Islands, Antarctica

Seabirds play an important role as top consumers in the food web and can be used as biomonitors of exposure to pollutants. Contamination studies involving non-destructive sampling methods are of considerable importance, allowing better evaluation of the levels of pollutants and their toxic effects. In the present study, organohalogen contaminants were analyzed in 113 blood samples from Southern Giant Petrel (Macronectes giganteus) adults and chicks collected in the austral summer of 2011/2012 and 2012/2013 from colonies on Elephant and Livingston Islands, South Shetland, Antarctica. Polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB), pentachlorobenzene (PeCB), mirex, dichlorodiphenyltrichloroetane and derivatives (DDTs) and chlordanes were detected in all birds, whereas polybrominated diphenyl ethers (PBDEs) were not detected in any blood samples. No significant differences were found in organochlorine levels between sampling events. Adults exhibited significantly higher levels than chicks, except for PeCB. PCBs, HCB, mirex and DDTs were statistically similar in males and females from Elephant Island. Females on Livingston Island exhibited higher HCB values than males, but no sex differences were found regarding other organochlorines. The similarity in organochlorine levels between sexes in birds with very marked sexual segregation in feeding habits during the breeding season may indicate that significant amounts of contaminants are acquired during migration to lower latitudes, when the diets of males and females are similar. Birds sampled on Livingston Island exhibited significantly lower levels of PCBs, HCB, DDTs, mirex and chlordanes in comparison to those on Elephant Island, which could be the result of distinct foraging patterns between the two colonies. Organochlorine levels were similar between years in birds captured in two consecutive breeding seasons. Blood samples from Southern Giant Petrels adults and chicks proved to be useful for the comparison of intraspecific contamination levels and appear to be adequate for the long-term assessment of organohalogen contaminants in antarctic top predators.Organochlorine contaminants in blood samples of Southern Giant Petrels reflected intra-specific differences and suggested distinct foraging patterns between colonies.

Assessment of PCB and chlorinated pesticide accumulation in mussels at Kaštela Bay (Eastern Adriatic)

The biological response of mussels Mytilus galloprovincialis, resident and transplanted to cages, to contamination with anthropogenic pollutants from Kaštela Bay, located in the central part of the eastern Adriatic coast, was investigated. The main purpose of this paper is to trace the accumulation of PCBs and chlorinated pesticides (HCB, lindane, heptachlor, aldrin, p,p′-DDTs) as a direct measure of potential contaminant availability to organisms, in a period from 2000 to 2011. In order to do so, cultured mussels (Mytilus galloprovincialis) of the same size and age were transplanted from the unpolluted Mali Ston Bay to the Kaštela Bay. Sampling was performed bimonthly, and the level of target contaminants in whole soft tissue was determined. After two months of exposure, the concentration of PCBs in transplanted mussels increased on average 6.5-times, and of DDTs 2-times, while the intensity of changes for HCB, lindane, heptachlor and aldrin was negligible. Seasonal variation of pesticide content was similar without a significant change throughout the experimental period, while that of PCBs was somewhat different showing increased accumulation in summer. Seasonal and spatial variation of organochlorines in the Kaštela Bay was likely the result of prevailing environmental rather than biological parameters. In accordance with prevailing hydrodynamic cycling, contaminant concentration decreased in acyclonic direction towards the exit of the Bay. Measurement of target contaminants in resident mussels sampled from the most contaminated area of the Bay exhibited decreasing concentrations of lindane, aldrin and p,p′-DDTs. However, PCBs exhibited statistically significant increasing concentrations in relation to the slightly increasing concentrations of HCB. With regard to human health, organochlorine (OC) levels in the mussel tissue were below prescribed limits for human consumption.

Levels of Organochlorine and Organophosphorus Pesticide Residues in Water and Soil of Musi River Belt Area Hyderabad, India

Levels of Organochlorine and Organophosphorus Pesticide Residues in Water and Soil of Musi River Belt Area Hyderabad, India

Associations between Obesity, Body Fat Distribution, Weight Loss and Weight Cycling on Serum Pesticide Concentrations.

Preliminary studies suggest pesticides may be linked to increased cancer risk. Since most pesticides are lipophilic and stored within adipose tissue, serum levels of organochlorines are affected not only by environmental exposures, but also by factors related to lipid turnover and storage. Our objective was to investigate whether serum organochlorines are influenced by weight loss, body fat distribution, and weight cycling. Ten overweight women were recruited upon entry into a weight loss program and surveyed regarding weight history, childbearing/lactation, and exposure to environmental contaminants. Anthropometric measures and phlebotomy were conducted at baseline and at four weeks (mean weight loss=5.1 kg). Serum was analyzed for 19 common polychlorinated pesticides and metabolites and 10 PCB congeners. Organochlorine levels were not significantly affected by weight loss nor associated with body mass index (BMI). Strong positive correlations were noted between levels of DDE/DDT and age (DDE β=0.6986/p=0.0246/DDT β=0.6536/p=0.0404) and between DDE/DDT and waist-to-hip ratio (WHR) (DDE β=0.4356/p=0.0447/DDT β=0.8108/p=0.0044). Trends were noted for decreased levels of DDT in women who reported more episodes of weight cycling. Serum organochlorine levels may be affected not only by age, but also factors related to lipid turnover (i.e., episodes of weight cycling and WHR), and warrants further study.

Residues Analysis of Organochlorine Pesticides in Fish, Sediment and Water Samples from Tekeze Dam, Tigray, Ethiopia

The study was conducted to assess the levels of organochlorine (OC) pesticide residues in Lake TeKeze dam have been investigated using water, sediment and fish (Labeobarbusspp, Clariasgariepinus and Oreochromis niloticus) samples as a case study to find out the extent of pesticide contamination and accumulation in the lake. Six OC pesticides namely DDT, DDE, Lindane, Endosulfan, Heptachlor and Chlordane were analyzed in four sites at two seasons. Water samples were processed using a liquid-liquid extraction technique and gas chromatograph equipped with electron capture detector (GC-ECD). Soxhlet extraction was used for fish and sediment samples followed by clean up and gas chromatograph. DDE was the predominant residue in all the samples analyzed, at the mean concentrations of 0.052 ppb, 9.80 ppb and 4.81 ppb in water, sediment and fish samples, respectively. The lowest levels of OC pesticides were related to Heptachlor and Chlordane which none of them were found in water samples. It also indicated the extensive presence and usage of these pesticides in the study environment, which include recent use of this pesticide for agricultural purposes. Thus, the use of these pesticides to control pest by farmers within the study area with little or no knowledge must be checked through adequate control of the trade and use of pesticides and the enforcement of appropriate sanctions.

Analysis of Organochlorine and Organophosphorus Pesticide Residues in Dairy Products and Baby Foods from Egyptian Markets

The residue levels of organochlorine (OCP) and organophosphorus (OPP) in some dairy products and baby foods samples in Assiut markets Egypt were determined. The concentrations of OCP and OPP were determined in milk powder, plain yoghurt, fruit yoghurt, breakfast cereals, wheat cereal-based baby foods, rice cereal-based baby foods and vegetables and fruit-based baby foods by gas chromatography/mass spectrometry. In dairy products, the highest values of OCP and OPP were 9.346 ± 0.950 μg/kg methoxychlor in fruit yoghurt and 2.282 ± 0.400 μg/kg disulfoton in plain yoghurt, respectively. Propachlor, dieldrin (OCP), chlorpyrifos, and parathion- methyl (OPP) were not detected in any dairy product samples. Maximum amounts of methoxychlor (12.710 ± 0.700 μg/kg) and disulfoton (5.369 ± 0.510 μg/kg) were recorded in vegetables and fruit-based baby foods, and wheat cereal-based baby foods, respectively. The analysis of dairy products and baby foods showed lower pesticides values than the permissible limit set by the European Commission in all products, except methoxychlor (OCP) in vegetables and fruit-based baby foods. The results will help in a scientific assessment of the implications of pesticide residues with regards to human risks in Egypt.

Short-term fasts increase levels of halogenated flame retardants in tissues of a wild incubating bird

Many species are adapted for fasting during parts of their life cycle. For species undergoing extreme fasts, lipid stores are mobilized and accumulated contaminants can be released to exert toxicological effects. However, it is unknown if short-term fasting events may have a similar effect. The objective of this study was to determine if short successive fasts are related to contaminant levels in liver and plasma of birds. In ring-billed gulls (Larus delawarensis), both members of the pair alternate between incubating the nest for several hours (during which they fast) and foraging, making them a useful model for examining this question. Birds were equipped with miniature data loggers recording time and GPS position for two days to determine the proportion and duration of time birds spent in these two activities. Liver and plasma samples were collected, and halogenated flame retardants (HFRs) (PBDEs and dechlorane plus) and organochlorines (OCs) (PCBs, DDTs, and chlordane-related compounds) were determined. Most birds (79%) exhibited plasma lipid content below 1%, indicating a likely fasted state, and plasma lipid percent declined with the number of hours spent at the nest site. The more time birds spent at their nest site, the higher were their plasma and liver concentrations of HFRs. However, body condition indices were unrelated to either the amount of time birds fasted at the nest site or contaminant levels, suggesting that lipid mobilization might not have been severe enough to affect overall body condition of birds and to explain the relationship between fasting and HFR concentrations. A similar relationship between fasting and OC levels was not observed, suggesting that different factors are affecting short-term temporal variations in concentrations of these two classes of contaminants. This study demonstrates that short fasts can be related to increased internal contaminant exposure in birds and that this may be a confounding factor in research and monitoring involving tissue concentrations of HFRs in wild birds.

Assessment of Organochlorine Pesticide Residues in Water, Sediments and Fish from Lake Tashk, Iran

In this study, the levels of organochlorine (OC) pesticide residues in Lake Tashk have been investigated using water, sediment and fish (carp) samples as a case study to find out the extent of pesticide contamination and accumulation in the lake. Six OC pesticides namely DDT, DDE, lindane, endosulfan, heptachlor and chlordane were analyzed in four sites at four seasons. Water samples were processed using a liquid–liquid extraction technique and gas chromatograph equipped with electron capture detector (GC-ECD). Soxhlet extraction was used for fish and sediment samples followed by clean up and gas chromatograph. DDE was the predominant residue in all the samples analyzed, at the mean concentrations of 0.075ppb, 8.750ppb and 4.446ppb in water, sediment and fish samples, respectively. The lowest levels of OC pesticides were related to heptachlor and chlordane which none of them were found in water samples. Gonban and Midstream sites had the highest and the lowest concentrations of OC pesticides, respectively.

Inverse correlation among organochlorine pesticide levels to total lipid serum contents: a preliminary study in Veracruz, México.

Organochlorine pesticides, due to their hydrophobic nature and persistence, accumulate in tissues rich in lipids, which had been used as a biomarker for environmental pollution. In humans, organochlorine pesticides are continuously circulating and equilibrating among body compartments. The objective of the study was to evaluate the concentrations of organochlorine pesticides in blood serum and compare their levels to the total lipid contents in Veracruz, México inhabitants. Our hypothesis is that concentrations of organochlorine pesticides will increase just as lipid concentrations. Levels of organochlorine pesticides were divided in ascending tertils according to their total lipid content. The linear trend model applied surprisingly reveals that the average level of all organochlorine pesticides decreases as the lipid concentration increases. From one tertil to the next β-HCH, it shows a decrease of -3.19mgkg(-1) on lipid basis, pp.'DDE levels decrease by -3.70mgkg(-1) on lipid basis and pp.'DDT levels decrease -1.13mgkg(-1) on lipid basis. We conclude that the levels and the orderly sequence of organochlorine pesticide distributions in the blood serum maintain an inverse relationship to total lipid blood serum concentrations.

Exposure to polychlorinated biphenyls and hexachlorobenzene, semen quality and testicular cancer risk.

We carried out a case-control study to investigate the possible role of occupational and environmental exposure to endocrine disruptors in the onset of testicular cancer (TC). We evaluated 125 TC patients and 103 controls. Seminal fluid examination and organochlorine analysis were performed in all subjects. Cases and controls were also interviewed using a structured questionnaire to collect demographic information, residence, andrological medical history and dietary information. We found that a higher level of reproductive tract birth defects was associated with a higher risk of TC. With regard to diet, cases reported a higher consumption of milk and dairy products than controls. Overall, there was a statistically significant increase in TC risk in cases with detectable values of total polychlorinated organic compounds against controls (14.4 vs. 1.0 %; p < 0.001). TC patients with detectable levels of organochlorines had lower mean semen parameters than those with undetectable levels, although this difference was not statistically significant. The International Agency for Research on Cancer recently included dioxin-like polychlorinated biphenyls (PCBs) in Group 1 of known human carcinogens. Our study confirmed and identified various risk factors for testicular cancer: cryptorchidism, consumption of milk and dairy products, parents' occupation and serum concentration of hexachlorobenzene and PCBs and, for the first time, we showed the correlation between semen quality and the serum concentration of these pollutants.

Persistent organochlorines in 13 shark species from offshore and coastal waters of Korea: Species-specific accumulation and contributing factors

Data on persistent organochlorines (OCs) in sharks are scarce. Concentrations of OCs such as polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were determined in the muscle tissue of 13 shark species (n=105) collected from offshore (Indian and Pacific Oceans) and coastal waters of Korea, to investigate species-specific accumulation of OCs and to assess the potential health risks associated with consumption of shark meat. Overall OC concentrations were highly variable not only among species but also within the same species of shark. The concentrations of PCBs, DDTs, chlordanes, hexachlorobenzene, and heptachlor in all shark species ranged from <LOQ (limit of quantification) to 184 (mean: 35.0), <LOQ to 1135 (58.2), <LOQ to 56.2 (4.31), <LOQ to 18.8 (1.64) and <LOQ to 77.5 (1.37)ng/g lipid weight, respectively. The determined concentrations of PCBs and DDTs in shark in our study were relatively lower than those reported in other studies. Aggressive shark species and species inhabiting the Indian Ocean had the highest levels of OCs. Inter-species differences in the concentrations and accumulation profiles of OCs among shark species could be explained by differences in feeding habit and sampling locations. Several confounding factors such as growth velocity, trophic position, and regional contamination status may affect the bioaccumulation of OCs in sharks. Hazard ratios of non-cancer risk for all the OCs were below one, whereas the hazard ratios of lifetime cancer risks of PCBs and DDTs exceeded one, implying potential carcinogenic effects in the general population in Korea. This is the first report to document the occurrence of OCs in sharks from Korea.

Organochlorine levels in human blood from residents in areas of limited pesticide use in Sudan

Ninety-nine human blood samples were collected from the riverine region of northern Sudan and the traditional and mechanized rain-fed areas of western and eastern Sudan, representing areas of limited pesticide use in Sudan. Blood samples were analyzed for organochlorine pesticides by gas liquid chromatography (GLC) followed by electron-capture detection (ECD). p,p′-DDE (a metabolite of DDT), heptachlor epoxide, β-hexachlorocyclohexane (β-HCH), and dieldrin were detected in all locations surveyed. The level of total organochlorine burden was highest in the traditional rain-fed area, followed by the mechanized rain-fed area, and the riverine area. A highly significant correlation was observed between total organochlorine blood burden and the age of the donors (r = 0.608**).