Exposure to polychlorinated biphenyls in residents near a chemical factory in Italy: the food chain as main source of contamination

Factors affecting the polychlorinated biphenyl signatures in serum of adults living in a highly polluted area in eastern Slovakia

Introduction

Over the years eastern Slovakia has been subject to consistent monitoring of high levels of polychlorinated biphenyls (PCBs) in both the environment and human populations attributed to the former production of PCBs at the Chemko Strážske plant. We aimed to investigate the extent to which dietary habits and residential location could affect the concentrations of PCBs in the blood serum samples of subjects.

Methods

We enrolled 602 adult subjects from eastern Slovakia with an average age of 45.14 (±8.49) years. To determine the concentrations of 21 PCB congeners, we used solid phase extraction along with gas chromatography coupled with high-resolution mass spectrometry. Based on questionnaire data, the assessment of dietary habits and residential location was performed using score calculations and creating a map.

Results and discussion

Through principal component analysis, the 20 PCB congeners were classified into three groups: PC1, comprising highly chlorinated PCBs, and PC2 and PC3, consisting primarily of low chlorinated PCBs. Stepwise multivariate regression revealed positive and negative associations between PCB congeners represented by PC1-3 and scores related to the residential location and scores related to food consumption, respectively. We confirmed that levels of PCBs represented by PC1-3 increased with age. The geographical proximity to pollution sources proved to be a key contributing factor to the observed PCB levels in individuals residing in eastern Slovakia.

Human biomonitoring of PCDDs, PCDFs, and PCBs in women living in a Northern Italy industrial area

In Brescia , a highly industrialized city in the Lombardy Region (Northern Italy) classified as a SIN (Contaminated Site of National Interest), a human biomonitoring study was carried out on breast milk of two groups of women residing in areas with presumably different levels of exposure to polychlorodibenzo-p-dioxins, polychlorodibenzofurans, and polychlorobiphenyls. This study was aimed at evaluating the possible difference between women living in Brescia and women living far from it but in the same Region. Between 2016 and 2018, 82 women were enrolled (41 "exposed" subjects and 41 "not exposed"), breast milk samples were collected, and a specific questionnaire was administered to the donors. Data obtained were processed by robust regression and Principal Component Factor Analysis. The differences in concentration between the two groups were significant for all the classes of analytes (except for PCDDs). The concentration increase rates from the not exposed to the exposed group resulted highly significant: some PCB congeners showed increase rates more than 1000 ng/g lb per one-unit change of the independent variable. Among the variables significantly associated with the observed concentrations, age showed the greatest influence, while BMI showed a counteracting effect. Consumption of vegetable oil and fruit resulted to possibly influence the chemicals body burden. For the not exposed group, the levels appear to be in line with the decreasing trend (2001-2018) observed for these contaminants in Italy.

Combined process of chemically enhanced sedimentation and rapid filtration for urban wastewater treatment for potable reuse

The objective of this study is to propose a new post-treatment of effluents from Upflow Anaerobic Sludge Blanket (UASB) using rapid filtration, aiming at the production of water for potable reuse. The final quality of the effluent produced by the treatment using gravel, sand, clinoptilolite and activated carbon associated with disinfection was evaluated by physical chemical analysis, heavy metals and persistent organic contaminants. Experiments were carried out in jar test, filter operation time, evaluation of the efficiency using peracetic acid and free chlorine as disinfectant and all results were statistically analysed. The best conditions were those using 20 mg/L of ferric chloride and natural pH of the effluent (≈ 7.0), which resulted in less reagent consumption. The use of intermediate fund discharges made it possible to obtain approximately 91% of recovered water efficiency. The effluent treated under these conditions showed DOC <2.0 mg/L, COD <1.0 mg/L, BOD <1.0 mg/L, turbidity <1.0 NTU, TSS <1.0 mg/L, ammonia <0.1 mg/L, total phosphorus <0.1 mg/L and surfactants <0.1 mg/L. The disinfection process with free chlorine and PAA allowed the total inactivation of faecal coliforms and total coliforms. The treatment using rapid filtration with disinfection by chlorine reached the appropriate level for urban, environmental, industrial and indirect potable water reuse.

Polychlorinated Biphenyls and Semen Quality in Healthy Young Men Living in a Contaminated Area

Polychlorinated biphenyls (PCBs) are persistent organic pollutants and endocrine disruptors that have been implicated in potential damage to human semen. However, the studies conducted so far provide contrasting results. Our study aimed to investigate the associations between PCB serum and semen levels and semen quality in high school and university students living in a highly PCB-polluted area of Italy. Subjects with a normal body mass index who did not make daily use of tobacco, alcohol, drugs, or medication were selected. All participants provided a fasting blood and a semen sample. Gas chromatography-mass spectrometry was used to determine the concentrations of 26 PCB congeners. The concentrations of PCB functional groups and total PCBs were also computed. A total of 143 subjects (median age 20, range 18-22 years) were enrolled. The median total PCB concentrations were 3.85 ng/mL (range 3.43-4.56 ng/mL) and 0.29 ng/mL (range 0.26-0.32 ng/mL) in serum and semen, respectively. The analysis of the associations between sperm PCB concentration and semen parameters showed (a) negative associations between some PCB congeners, functional groups and total PCBs and sperm total motility; (b) negative associations of total PCBs with sperm normal morphology; and (c) no association of PCBs with sperm concentration. Subjects at the highest quartile of semen total PCB concentration had 19% and 23% mean reductions in total motility and normal morphology, respectively, compared to those at the lowest quartile. The analysis of the associations of serum PCB levels with sperm parameters yielded null or mixed (some positive, other negative) results. In conclusion, the present study provides evidence of a negative effect of some PCB congeners and total PCBs in semen on sperm motility and normal morphology. However, the associations between the concentration of serum and semen PCB congeners and functional groups and sperm quality parameters were inconsistent.

Comparison between Macro and Trace Element Concentrations in Human Semen and Blood Serum in Highly Polluted Areas in Italy

Macro and trace elements are important regulators of biological processes, including those ones linked to reproduction. Among them, Ca, Cu, Fe, K, Mg, Mn, Na, Se, and Zn ensure normal spermatic functions. Hence, the aim of this study was to evaluate the concentrations of 26 macro and trace elements (Al, As, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Li, Mg, Mn, Na, Ni, Pb, Rb, Sb, Se, Sn, Sr, U, V, and Zn) in blood serum and also in semen of healthy young men, homogeneous for age, anthropometric characteristics, and lifestyle, living in three highly polluted areas in Italy. Furthermore, a comparison among three geographical areas was performed to highlight any difference in the investigated parameters and, overall, to speculate any correlations between chemical elements and semen quality. Statistically significant differences (p < 0.05) among the three areas were found for each investigated element, in both semen and serum samples, where inter-area differences were more evident in semen than in blood serum, suggesting human semen as an early environmental marker. Considering the homogeneity of three cohorts, these differences could be due more to environmental conditions in the recruiting areas, suggesting that variations in those involved in reproductive-associated pathways can have an impact on male fertility. Nevertheless, more research is needed to evaluate threshold values for sperm dysfunction and male infertility. Actually, the role of different dietary intake and environmental exposure underlying the observed differences in the recruiting areas is under further investigation for the same cohort.

BMI modifies the association between dietary intake and serum levels of PCBs

Polychlorinated biphenyls (PCBs) are a group of persistent organic pollutants that are carcinogenic, neurotoxic, and endocrine disrupting in humans. Although diet is the primary source of exposure, there is no consensus on the association between dietary intake and serum PCBs. Additionally, body mass index (BMI) - with its inverse association with serum PCBs - may play a role in the association, which has never been studied. Therefore, we aimed to examine the association between dietary intake and serum levels of PCBs, and whether the association was modified by BMI. We used data from the National Health and Nutrition Examination Survey (NHANES) 2003-2004, including 1531 participants. We estimated dietary intake of PCBs using the 24-hour diet recall, USDA Food Composition Intake Database, and PCB content in foods from the Canada Total Diet Study. Serum PCBs were measured by high-resolution gas chromatography-mass spectrometry (HRGC-HRMS). We used linear regression to examine the associations of dietary PCB intake with serum levels of seven PCB congeners and six PCB metrics. Further, we explored the role of BMI in the associations. We found that participants who were older and non-Hispanic tended to have a higher serum level of ∑37-PCB. In addition, we observed positive associations between dietary intake and serum PCBs for: PCB 105, 118, 126, 138 + 158, and 153 (P value ranges 0.005-0.03); seven PCB indicators (P value = 0.03) and the sum of 37 PCBs (P value = 0.04). Furthermore, we observed an effect modification by BMI (P for interaction = 0.01 for ∑37-PCBs), with stronger associations in underweight or normal-weight individuals, and no association in overweight and obese individuals. In conclusion, within a cross-sectional, nationally representative sample of the US population, dietary PCB intake was positively associated with serum PCBs and the association was modified by BMI. Additional studies are warranted to replicate and confirm this effect modification.

Polychlorinated biphenyls and risk of hepatocellular carcinoma in the population living in a highly polluted area in Italy

Polychlorinated biphenyls (PCBs) are human carcinogens, based on sufficient evidence for melanoma and limited evidence for non-Hodgkin lymphoma and breast cancer. Few data are available for liver cancer, although PCBs cause it in rats and determined liver damage in poisoned people. We investigated the association between PCB serum levels and hepatocellular carcinoma (HCC) with a case-control study in a PCB-polluted area in North Italy. We enrolled prospectively 102 HCC incident cases and 102 age and gender-matched hospital controls. Serum concentrations of 33 PCB congeners were determined by a gas chromatograph coupled to mass spectrometry. Of 102 HCC cases, 62 who had lost < 3 kg of body weight in past 3 years were included in the analysis (67.7% males, mean age 68 years). The odds ratio (OR) for HCC for 3rd compared to 1st tertile of PCB distribution was 1.76 (95% confidence interval 0.62-5.03) for total PCB, adjusting for socio-demographic variables and risk factors for HCC by logistic regression. For most PCB congeners, ORs > 1.5 or 2 were found, although the 95% CIs included the null value for almost all of them. This preliminary study suggests that PCBs might play a role in HCC development.

Polychlorinated biphenyls (PCBs) and risk of dementia and Parkinson disease: A population-based cohort study in a North Italian highly polluted area

BACKGROUND

Serum polychlorinated biphenyls (PCBs) have been associated with some chronic diseases, but little evidence exists on their possible relationship with neurodegenerative diseases. We aimed to assess the relationship between PCB exposure and the occurrence of dementia and Parkinson disease in a prospective cohort study in a highly polluted area (Brescia-Caffaro).

METHODS

PCB exposure was assessed by measuring serum levels of 24 congeners. Data on the onset of dementia and Parkinson disease were retrieved by the Brescia Health Protection Agency Database. We used Poisson regression models adjusted for possible confounders to calculate rate ratios (RRs). A mediation analysis was performed to evaluate the mediatory role of cardiovascular diseases.

RESULTS

699 subjects without neurologic diseases at baseline were enrolled (48.1% males, 63.2 years of mean age) in 2001-2013 and followed up to 2018. During a mean follow-up of 8.8 years, 36 and 20 subjects developed dementia and Parkinson disease. Subjects in the 2nd and 3rd tertiles of the total PCBs distribution, compared with those in the 1st tertile, had a higher risk of dementia (RR = 2.30 and RR = 4.35). The estimates for Parkinson disease included the null value with wide confidence intervals. In the mediation analysis, the association between PCB exposure and dementia was dominated by the direct pathway and not by the hypertension-mediated pathway.

CONCLUSIONS

We observed a positive association between total PCBs serum levels and the onset of dementia not mediated by hypertension. For Parkinson, the unstable risk estimates did not allow to draw a conclusion on a possible association.

Short-chain chlorinated paraffins in various foods from Republic of Korea: Levels, congener patterns, and human dietary exposure

Short-chain chlorinated paraffin (SCCP) concentrations in 419 food samples (from 59 species) from Republic of Korea were determined. The SCCP concentrations and lipid contents in whole foods positively correlated and the highest SCCP concentration (891 ng/g wet weight) was observed in fats and oils. The SCCP concentrations were higher in benthic fish/shellfish and demersal fish than other fish and shellfish. The SCCP concentrations were higher in duck meat and eggs than meat and eggs of other species. The chlorine-based congener group patterns were related to the lipid contents of the foods. SCCPs in eggs (high lipid content) were dominated by more-chlorinated SCCPs (particularly Cl₈-SCCPs, which contributed 43% of the total) but SCCPs in seaweed (low lipid content) were dominated by less-chlorinated SCCPs (particularly Cl₆-SCCPs, which contributed 46%). Dietary SCCP intakes were calculated using the median SCCP concentrations and estimated 888 and 781 ng/kg/d for male and female Korean adults, respectively. The predominant contributing foods to SCCP dietary exposure differed according to sex and age. Dairy products contributed most (about 50%) for infants/children (1-5 y old), but meat and dairy products contributed most for adult males and females, respectively. Grain contributed most for ≥65 y old.

Polychlorinated biphenyls (PCBs) and risk of hypertension: A population-based cohort study in a North Italian highly polluted area

This study aimed to assess the longitudinal association between PCB exposure and the subsequent occurrence of hypertension in a highly polluted area. The study subjects had at least one PCB serum measurement between 2003 and 2014 and were followed up to the end of 2017. Hypertension cases were obtained from the Brescia Health Protection Agency database. Risk ratios of hypertension for total PCBs, high-, middle- and low-chlorinated groups and some common congeners were estimated using Poisson regression models. 1031 subjects were included (43.4% males, mean age 45.3 years). 229 subjects developed hypertension during the follow-up. Total PCBs, middle- and high-chlorinated PCBs, and particularly PCB congeners 138, 153 and 180 were associated with an about 2-fold increased risk of hypertension comparing the third with first tertile of distribution. After lipid-standardization of PCB serum values, the excess risk showed only a slight attenuation. A dose-response linear relationship of the risk of hypertension by PCB serum concentrations as continuous variables was also observed. The PCBs-hypertension association was stronger in overweight/obese subjects than those with normal body mass index. In this prospective cohort study the serum levels of total and middle to high chlorinated (≥6 Cl) PCBs were associated with an increased risk of hypertension, particularly among overweight/obese subjects.

Health risks and source identification of dietary exposure to indicator polychlorinated biphenyls (PCBs) in Lanzhou, China

Polychlorinated biphenyls (PCBs) are widely present in multiple environmental media even long after the phaseout, posing a health risk to the general population. Dietary intake is the major exposure route of PCBs; however, information is limited regarding PCBs in food that people directly consume. This study aims to measure personal exposure to indicator PCBs, evaluate the health risks, and identify their sources in a typical metropolitan city in China. Multi-day food samples were collected from 21 subjects in Lanzhou, Gansu Province, in two seasons using the duplicate plate method. Samples were extracted and analyzed for seven indicator PCBs using gas chromatography/mass spectrometry. Average daily doses (ADDs) of ∑7PCBs were estimated using Monte Carlo analysis with food intake information. Results show that PCB-118 and PCB-180 were the major congeners in food samples with average concentrations of 1.42 and 1.11 ng/g, respectively. The average (± SD) ADD of ∑7PCBs was 26.47 ± 22.10 ng/kg day among adults aged 18-69 years and displayed small variation across age groups. Comparing with the chronic RfD of 7 ng/kg day, 67% of people had their ADDs exceeding this threshold. The median cancer risk was 5.52 × 10^-5, and 51% of residents had risks exceeding the action level of 10^-4. The principal component analysis identified waste incineration, gasoline engine production, and leakage of #1 PCBs as the major PCBs sources. In conclusion, a large portion of Lanzhou residents has high non-cancer and cancer risks from dietary exposure to PCBs, which warrants control actions targeting these major sources.

Serum levels of polychlorinated biphenyls and risk of non-Hodgkin lymphoma: A hospital-based case-control study

Polychlorinated biphenyls (PCB) have been classified by the International Agency for Research on Cancer (IARC) in Group 1 as carcinogenic to human, based on sufficient evidence in humans of an increased risk of cutaneous malignant melanoma and limited evidence for non-Hodgkin lymphoma (NHL). However present findings on the association of PCB exposure and NHL are still controversial. This study examined the relationship between PCB serum levels and risk of NHL in a Northern Italy area (Brescia province), where a chemical factory produced PCBs from 1938 to 1984, causing human contamination. A case-control study of 215 NHL patients and 215 control subjects was conducted. Cases and controls were assayed for serum levels of 33 PCB congeners. No associations were found between risk of NHL and serum levels of total PCBs (OR = 0.51; 95% CI: 0.25-1.04 for highest vs lowest quartile) or specific PCB congeners. The study confirmed a strong association of NHL with HCV infection (OR = 3.60; 95% CI: 1.30-10.02). This case-control study does not support the hypothesis of an association between current serum levels of PCBs and NHL development in the general population.

Polychlorinated biphenyl serum levels, thyroid hormones and endocrine and metabolic diseases in people living in a highly polluted area in North Italy: A population-based study

Polychlorinated biphenyls (PCBs) are persistent organic pollutants produced until the 1980s, which they are still present worldwide. They have been associated with metabolic and endocrine diseases and hypertension in humans, but definite evidence is lacking. A chemical factory producing PCBs caused a heavy pollution in an urban area in Northern Italy. We aimed to evaluate present PCBs serum levels according to demographic and lifestyle variables and their associations with endocrine and metabolic diseases and hypertension in the resident general population. A random sample of 816 adults aged 20–79 years (mean ± SD: 49.1 ± 16.5 years) was enrolled in a cross-sectional population-based study. The participants provided a fasting blood sample for laboratory analysis and were face-to-face interviewed about the presence of chronic diseases. The serum level of total PCBs was computed as the sum of 33 PCB congeners. The median serum level of lipid-adjusted total PCBs was 435.2 and 95^th centile was 2154.9 ng/g lipid. Medium and high chlorinated PCBs with immunotoxic and endocrine disrupting activity contributed most to total PCB serum levels, particularly PCBs 138, 153, 170, 180 and 194. The serum levels of total PCBs and of PCB functional groups were positively associated with age and negatively with female gender, education, smoking habit and BMI, and not associated with serum levels of thyroid hormones and TSH and glycaemia and with presence of endocrine diseases, diabetes and hypertension by multivariable analysis. Subgroup analyses according to gender, age and BMI provided similar results. In conclusion, this study shows a long-term persistence of past exposure to PCBs and does not support the hypothesis of an association between PCB exposure and prevalence of endocrine and metabolic diseases and hypertension.

The spatial distribution of congener-specific human PCB concentrations in a PCB-polluted region

Serum PCB congener concentrations were measured in 602 adults living near a PCB pollution source in eastern Slovakia. We created isoconcentration maps for 21 PCB congeners by geocoding each participant's place of residence and kriging. Concentrations of PCB congeners were inversely associated with the distance of the participants' residence from the source of pollution. Congener-specific risk factors were derived, particularly for PCBs 52 and 153. We observed that the spatial distribution of serum concentrations was influenced by micro-climatic parameters and physicochemical properties of the congeners. PCB congener profiles strongly correlated with that of the PCB commercial product Delor 106, which was manufactured in the region. The isoconcentration maps indicate that the zones with the highest predicted congener concentration have a mean area of approximately 235.75±188.56km² and the mean enrichment of concentration of congeners in serum in these zones is about 5.12±1.36. We estimate that depending on congener approximately 23,457±18,762 individuals with PCB concentrations exceeding health-based guidance values live in these zones.

Polychlorinated biphenyls (PCBs) exposure and cardiovascular, endocrine and metabolic diseases: A population-based cohort study in a North Italian highly polluted area

BACKGROUND AND AIMS

Exposure to polychlorinated biphenyls (PCBs) has been linked to the onset of cardiovascular, endocrine, and metabolic diseases, but no conclusive evidence has been provided so far. A chemical factory produced PCBs from 1938 to 1984 in Brescia (North Italy) resulting in environmental contamination and human exposure. We aimed to evaluate the association between PCB serum levels and subsequent incidence of chronic diseases through a prospective cohort study design.

METHODS

Based on surveys conducted in Brescia province between 2001 and 2013, a cohort of 1331 subjects with at least one measure of PCB serum levels during the period was selected and followed longitudinally. Serum concentration of total PCBs was computed summing up the levels of 24 PCB congeners determined by gas chromatography. The data on incidence of hypertension, cardiovascular diseases, and endocrine and metabolic chronic diseases were retrieved from the Brescia Health Protection Agency database. Poisson regression models adjusted for age, level of education, BMI, cholesterol level, tobacco smoking and alcohol drinking were employed to calculate rate ratios (RRs).

RESULTS

1331 subjects were enrolled (45.7% males, mean age 50.6 years) contributing to 10,006 person-years of follow-up. A dose-response relationship was observed between PCB serum levels and the onset of hypertension (RR for 2nd and 3rd tertiles of serum PCB distribution: 2.07, 95% CI 1.18-3.63, and 2.41, 1.30-4.47, respectively). A possible, though not statistically significant, increase of the risk of cardiovascular disease was also found (RR for 2nd and 3rd tertiles of serum PCB distribution: 1.61, 0.72-3.64, and 1.96, 0.86-4.48, respectively). The results based on lipid-standardized PCBs were slightly attenuated. No association was found between PCB serum levels and occurrence of diabetes and endocrine disorders. Stratified analysis by body mass index showed an increased risk of hypertension in subjects at 2nd and 3rd tertile of serum PCB distribution in overweight/obese subjects only.

CONCLUSIONS

These results suggest that PCBs might play a role in the development of hypertension and possibly cardiovascular disease, though alternative explanations are to be considered too.

Plasma levels of polychlorinated biphenyls and risk of cutaneous malignant melanoma: A hospital-based case-control study

Polychlorinated biphenyls (PCB) have been classified by the International Agency for Research on Cancer (IARC) in Group 1 as carcinogenic to human, based on sufficient evidence in humans of an increased risk of cutaneous malignant melanoma (CMM), however few studies have been done in the general population. This study examined the relationship between PCB plasma levels and risk of CMM adjusting for sun sensitivity and sun exposure in a province of Northern Italy (Brescia), where a chemical factory produced PCBs from 1938 to 1984 causing human contamination. A case-control study of 205 CMM patients and 205 control subjects was conducted. Cases and controls were assayed for plasma levels of 33 PCB congeners. No associations was found between risk of CMM and plasma levels of total PCB (OR = 0.81; 95% CI: 0.34-1.96 for highest vs lowest quartile) or specific congeners. The study confirmed the association with light skin colour (OR = 3.00; 95% CI: 1.91-4.73), cumulative lifetime UV exposure (OR = 2.56; 95% CI: 1.35-4.85) and high level of education (OR = 1.45; 95% CI: 1.03-2.05). This case-control study does not support the hypothesis of an association between current plasma levels of PCBs and CMM development in the general population.

Do environmental dynamics matter in fate models? Exploring scenario dynamics for a terrestrial and an aquatic system

Nowadays, there is growing interest in inserting more ecological realism into risk assessment of chemicals. On the exposure evaluation side, this can be done by studying the complexity of exposure in the ecosystem, niche partitioning, e.g. variation of the exposure scenario. Current regulatory predictive approaches, to ensure simplicity and predictive ability, generally keep the scenario as static as possible. This could lead to under or overprediction of chemical exposure depending on the chemical and scenario simulated. To account for more realistic exposure conditions, varying temporally and spatially, additional scenario complexity should be included in currently used models to improve their predictive ability. This study presents two case studies (a terrestrial and an aquatic one) in which some polychlorinated biphenyls (PCBs) were simulated with the SoilPlusVeg and ChimERA models to show the importance of scenario variation in time (biotic and abiotic compartments). The results outlined the importance of accounting for planetary boundary layer variation and vegetation dynamics to accurately predict air concentration changes and the timing of chemical dispersion from the source in terrestrial systems. For the aquatic exercise, the results indicated the need to account for organic carbon forms (particulate and dissolved organic carbon) and vegetation biomass dynamics. In both cases the range of variation was up to two orders of magnitude depending on the congener and scenario, reinforcing the need for incorporating such knowledge into exposure assessment.

Endocrine Disrupters and the Safety of Food Chains

Endocrine disrupters (ED) are a heterogeneous group of chemicals including persistent contaminants, pesticides, as well as compounds present in consumer products and natural substances. For most ED, the food chain is a current major exposure route for the general population. ED can enter the food chain through the living environment (e.g., feeds, fertilizers) of food-producing organisms, be directly employed in food production (e.g., pesticides) or be released from food contact materials (such as bisphenol A or phthalates); in addition, the endocrine disruption potential of some natural compounds in edible plants, including the so-called phytoestrogens, should not be overlooked. An exposure assessment has to consider the specific liability of food commodities to contamination with specific ED (e.g., polychlorinated and polybrominated chemicals in lipid-rich foods). The paper discusses the main toxicological research issues in order to support the risk assessment of ED in food chains, including: the potential for additive, 'cocktail' effects (as from multiple pesticide residues); the long-term effects on target body systems (e.g., reproductive, nervous) elicited by exposure during prenatal as well as postnatal life stage windows, and toxicant/nutrient interactions (e.g., thyroid-targeting ED and iodine status). Food safety systems should exploit the available knowledge to improve prevention of long-term risks along the whole food chain.

Food contamination by PCBs and waste disposal crisis: Evidence from goat milk in Campania (Italy)

AIM

The study aims at investigating whether, and if so, to what extent the strong presence of urban and industrial waste in a territory may cause PCB contamination in goat milk produced therein.

METHODS

We compared PCB concentrations in goat milk from three different locations in the Campania region (Italy). One of the three locations, together with its surrounding area, has long suffered from illegal waste disposal and burning mainly by the so-called Ecomafia. The other locations, not involved in these illegal activities, allowed us to create a control group of goats with characteristics very similar to those of main interest.

RESULTS

In milk from the waste contaminated area we identified high PCB concentrations (six indicator PCBs amounted to 170 ng g^-1 on lipid weight, on average), whereas there was an almost total absence of such pollutants in milk from the control group. Concentrations of the six indicator PCBs were above the current European maximum residue limit fixed by the EU. At the same time, we found a lower average value of lipid content and a negative relationship between lipid content and PCB concentrations.

CONCLUSION

Evidence indicates the potential health risk for consumers living in areas involved in illegal dumping of waste.

Differential neurotoxic effects of in utero and lactational exposure to hydroxylated polychlorinated biphenyl (OH-PCB 106) on spontaneous locomotor activity and motor coordination in young adult male mice

We investigated whether in utero or lactational exposure to 4-hydroxy-2',3,3',4',5'-pentachlorobiphenyl (OH-PCB 106) affects spontaneous locomotor activity and motor coordination in young adult male mice. For in utero exposure, pregnant C57BL/6J mice received 0.05 or 0.5 mg/kg body weight of OH-PCB 106 or corn oil vehicle via gavage every second day from gestational day 10 to 18. For lactational exposure, the different groups of dams received 0.05 or 0.5 mg/kg body weight of OH-PCB 106 or corn oil vehicle via gavage every second day from postpartum day 3 to 13. At 6-7 weeks of age, the spontaneous locomotor activities of male offspring were evaluated for a 24-hr continuous session in a home cage and in an open field for 30-min. Motor coordination function on an accelerating rotarod was also measured. Mice exposed prenatally to OH-PCB 106 showed increased spontaneous locomotor activities during the dark phase in the home cage and during the first 10-min in the open field compared with control mice. Mice exposed lactationally to OH-PCB 106, however, did not show a time-dependent decrease in locomotor activity in the open field. Instead, their locomotor activity increased significantly during the second 10-min block. In addition, mice exposed lactationally to OH-PCB 106 displayed impairments in motor coordination in the rotarod test. These results suggest that perinatal exposure to OH-PCB 106 affects motor behaviors in young adult male mice. Depending on the period of exposure, OH-PCB 106 may have different effects on neurobehavioral development.

Differentiating current and past PCB and PCDD/F sources: The role of a large contaminated soil site in an industrialized city area

Cities and contaminated areas can be primary or secondary sources of polychlorinated biphenyls (PCBs), dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and other chemicals, into air and soil and can influence the regional level of some of these pollutants. In a contaminated site, the evaluation of such emissions can be crucial in the choice of the remediation technology to be adopted. In the city of Brescia (Northern Italy), more than 100 ha of agricultural areas were contaminated with PCBs, PCDD/Fs and heavy metals, originating from the activities of a former PCB factory. In order to evaluate the current emissions of PCBs and PCDD/Fs from the contaminated site, in a location where other current sources are present, we compared measured and predicted air concentrations, resulting from chemical volatilization from soils as well as fingerprints of Brescia soils and of soils contaminated by specific sources. The results confirm that the contaminated area is still a current and important secondary source of PCBs to the air, and to a lesser extent of PCDFs (especially the more volatile), but not for PCDDs. PCBs in soils have fingerprints similar to highly chlorinated mixtures, indicating contamination by these mixtures and/or a long weathering process. PCB 209 is also present at important levels. PCDD fingerprints in soil cannot be related to current emission sources, while PCDFs are compatible to industrial and municipal waste incineration, although weathering and/or natural attenuation may have played a role in modifying such soil fingerprints. Finally, we combined chemical and microbiological analyses to provide an integrated approach to evaluate soil fingerprints and their variation in a wider perspective, which accounts for the mutual effects between contamination and soil microbiota, a pivotal hint for addressing in situ bioremediation activities.

Substantial decline of polychlorinated biphenyls serum levels 10years after public health interventions in a population living near a contaminated site in Northern Italy

INTRODUCTION

Polychlorinated biphenyls (PCBs) are persistent pollutants classified among endocrine disruptors and human carcinogens. In an urban area in Northern Italy (Brescia), a chemical factory producing PCBs from 1938 to 1984 caused soil and food pollution. Since the discovering of the environmental pollution in the area in 2001, various public health interventions have been implemented to avoid human contamination.

METHODS

Two independent surveys were carried out in 2003 and 2013 using the same study design and methods. A random sample of the adult general population living in four areas of the town with different soil contamination level was enrolled in both surveys. Investigation included serum levels of 24 PCB congeners and of other common clinical-chemical parameters and questions about residential and occupational history as well as current and past diet and consumption of locally produced food. 537 subjects were tested in the 2003 and 488 in the 2013 survey.

RESULTS

Total PCB serum levels showed a strong correlation with age (Spearman r=0.71 in 2003 and r=0.80 in 2013), but not with gender. Consumers of food produced in the most polluted area had higher total PCB serum levels (median 15.6 and 4.7ng/ml in 2003 and 2013, respectively) than non-consumers (4.1 and 2.3ng/ml) and consumers of food produced in non-polluted areas (6.5 and 1.9ng/ml), with increasing trend of PCB serum levels with cumulative local food intake. PCB serum levels from 2003 to 2013 survey declined by around half in all age groups, especially among the youngest people. The total PCB reduction was found to be due to a combination of a birth cohort effect (-41% every 10years) and survey period effect (-18% in 2013 versus 2003), with medium chlorinated CB congeners showing the most relevant reduction (-30%) between the two surveys. High chlorinated CBs were more strongly associated with birth cohort (-46% every 10years): in the 2013 survey they represented 58% of total PCBs in 60-79years old while they were 37% among the under 40s with a median value 20 times higher in the oldest than in the youngest (3.1 versus 0.16ng/ml).

CONCLUSIONS

PCBs serum levels declined from the 2003 to 2013 survey though they are still high in the elderly mainly because of past intake of locally produced contaminated food. Present findings suggest that PCBs food chain contamination and human absorption have been interrupted successfully in the area since discovery of the pollution in 2001.

Human Serum from Urban and Rural Adolescents and Their Mothers Shows Exposure to Polychlorinated Biphenyls Not Found in Commercial Mixtures

Although polychlorinated biphenyls are no longer sold as commercial mixtures, they are still being produced through modern manufacturing processes. We have previously shown that non-Aroclor PCB 11 is prevalent in indoor and outdoor air and sediment and detected in human serum. Here we report the prevalence of non-Aroclor PCB congeners (≤0.20 wt % in Aroclor) in human serum collected from urban and rural adolescents and their mothers. We hypothesized that additional non-Aroclor congeners are present in serum. Sera were extracted and detected for 209 PCBs using gas chromatography-tandem mass spectrometry. A list of 70 non-Aroclor PCB congeners was determined by measurement of original Aroclors. PCB 11, 14, 35, and 209 are the major dominating and most frequently detected congeners. PCB 14 and 35 have not been previously reported for environmental matrices. Adolescents have significantly lower total non-Aroclor PCB concentrations than mothers in East Chicago (p < 0.001) and Columbus Junction (p = 0.008). There are significant differences in non-Aroclor PCBs between East Chicago community and Columbus Junction community (p < 0.001). Non-Aroclor PCBs represent an average of 10% (and up to 50%) of total PCBs measured in serum. An average of 50% (and up to 100%) of these concentrations may be attributed to aryl azo and phthalocyanine paint pigments.

Case-study and risk management of dioxins and PCBs bovine milk contaminations in a high industrialized area in Northern Italy

Milk supplied to a dairy plant in Brescia City (Northern Italy) was found to be contaminated by dioxin like PCBs at levels above the European (EU) action limit (2 pg WHO-TEQ/g fat). As a consequence, 14 dairy farms were sampled individually, in order to identify and possibly eliminate the source of contamination. All the farms were located in Brescia or just nearby, an area that is characterized by a strong industrialization. Four out of the 14 farms showed contamination levels above the legal maximum limit set by European Commission at 5.5 pg WHO-TEQ/g fat for the sum of dioxins and DL-PCBs. Concentrations of 8.16, 6.83, 5.71 and 5.65 pg WHO-TEQ/g fat were detected. In the three most polluted farms, cow ration was substituted with feed coming from uncontaminated areas and the time needed to reduce milk pollution was evaluated. In all the three farms, contamination levels dropped below the EU legal limit after only 1 month from the removal of the pollution source. In each sampled farm, DL-PCBs were the major contributors to the total WHO-TEQ level, with percentages up to 87% in the most contaminated one. PCB 126 WHO-TEQ value explained by itself large part of this contamination, and its decrease was fundamental for the reduction of milk contamination levels. This study provides an example of an on-field successful emergency intervention that succeeded in decontamination of dairy cows, allowing a fast restart of their production activity.

Polychlorinated biphenyls and selected organochlorine pesticides in serum of Slovak population from industrial and non-industrial areas

The concentrations of indicator polychlorinated biphenyls (PCBs No. 28, 52, 101, 138, 153 and 180) and organochlorine pesticides (HCB, p,p'-DDE and p,p'-DDT) in 121 blood serum specimens collected from non-occupationally exposed adults living in contaminated and comparison areas were determined using high-resolution gas chromatography/electron capture detection (HRGC/ECD). The sum of the serum concentrations of the three most abundant PCB congeners (No. 138, 153 and 180) found in participants (N = 81) living in industrial areas near incinerators, metallurgical and chemical plants (Krompachy, Kosice, Nemecka and Sala) was significantly higher (p < 0.001) than in participants living in villages and towns without known sources causing persistent organic pollutant (POP) contamination (N = 40). Similarly, significant differences were observed for p,p'-DDE (p < 0.0001) and p,p'-DDT (p < 0.002). However, a Mann-Whitney U test between groups showed that the difference for HCB was not statistically significant (p = 0.089). Age was positively correlated with the sum of PCBs (No. 138, 153 and 180), HCB and the sum of p,p'-DDE and p,p'-DDT (p < 0.01 for all).

Study of penetration behavior of PCB-DNAPL in a sand layer by a column experiment

To better understand the infiltration performances of high concentration PCB oils (KC-300 and KC-1000 polychlorinated biphenyl (PCB) mixtures), representative dense non-aqueous phase liquid (DNAPL), under both saturated and unsaturated conditions, we conducted experiments on a sand column filled with Toyoura Standard Sand. When PCB oil with the volume comparable to the total porosity in the column was supplied, the residual PCB concentrations under PCB-water conditions were 4.9×10(4)mgkg(-1) in KC-300 and 3.9×10(4)mgkg(-1) in KC-1000. Under PCB-air conditions, residual PCB concentrations were 6.0×10(4)mgkg(-1) and 2.4×10(5)mgkg(-1) in the upper and lower parts for KC-300 and 3.6×10(4)mgkg(-1) and 1.5×10(5)mgkg(-1) in those for KC-1000, respectively, while the rest of the PCBs were infiltrated. On the other hand, when a small amount of PCB oil with the volume far smaller than the total porosity in the column was supplied, the original PCBs were not transported via water permeation. However, lower-chlorinated PCB congeners-e.g., di- or tri-chlorinated biphenyls-preferentially dissolved and were infiltrated from the bottom of the column. These propensities on PCB oil infiltration can be explained in conjunction with the degree of PCB saturation in the sand column.

Persistent organic pollutants distribution in lipoprotein fractions in relation to cardiovascular disease and cancer

Persistent organic pollutants (POPs) are lipophilic environmental toxins that have been associated with cardiovascular disease (CVD) and cancer. The aim of this study was to investigate the concentrations of POPs in human high and low/very low-density lipoproteins (HDL and LDL/VLDL) and the possible association with CVD and cancer occurrence in individuals living in a contaminated area. Lipoproteins from 28 individuals (7 healthy controls, 8 subjects with cancer, 13 subjects with CVD) were isolated and the fraction-specific concentration of 20 different POPs was analyzed by high resolution gas chromatography/high resolution mass spectrometry. The activity of Paraoxonase 1 (PON1), an anti-oxidant in HDL, was determined in plasma of these 28 subjects and additional 50 subjects from the same area excluding diseases other than cancer or CVD. Fourteen polychlorinated biphenyls (PCBs) and three organochlorine pesticides were detected, and especially highly chlorinated PCBs were enriched in lipoproteins. Significantly higher concentrations of POPs were found among individuals with CVD or cancer compared to controls. Principal component analyses showed that POP concentrations in HDL were more associated with CVD, while POP concentrations in LDL/VLDL were more associated with cancer. PON1 activity was negatively correlated to sumPCB and a co-variation between decreased arylesterase-activity, increased PCB concentrations and CVD was found. This study shows that POPs are present in lipoproteins and were more abundant in individuals with CVD or cancer compared to healthy controls. The results also indicate that PCB exposure is accompanied by reduced PON1 activity that could impair the HDL function to protect against oxidation.

PCBs levels and indicator congeners in children's and adolescents' hair

Thirty polychlorinated biphenyl (PCB) congeners were determined in the hair samples collected from children (4-12) and adolescents (13-18) of Changchun city, Northeastern China. The mean concentrations of total PCBs and dioxin-like PCBs (dl-PCBs) in the adolescents' hair samples were 161.0 ng g(-1) and 61.7 ng g(-1), which were relatively higher than 43.7 ng g(-1) and 14.6 ng g(-1) in the children's ones. Considering gender difference, the mean concentrations in the girls' hair samples were approximately two times higher than those in the boys' ones for most PCB congeners. The pentachlorinated biphenyl was the dominant homologue. It was found that the levels of total PCBs and dl-PCBs were highly correlated with PCB 118 level in the children's hair samples, and with PCB 114 level in the adolescents' ones. The result demonstrated that the two PCB congeners could be applied as the indicators to evaluate the concentrations of total PCBs and dl-PCBs in children's and adolescents' hair, respectively.

Environmental determinants of polychlorinated biphenyl concentrations in residential carpet dust

Polychlorinated biphenyls (PCBs), banned in the United Sates in the late 1970s, are still found in indoor and outdoor environments. Little is known about the determinants of PCB levels in homes. We measured concentrations of five PCB congeners (105, 138, 153, 170, and 180) in carpet dust collected between 1998 and 2000 from 1187 homes in four sites: Detroit, Iowa, Los Angeles, and Seattle. Home characteristics, occupational history, and demographic information were obtained by interview. We used a geographic information system to geocode addresses and determine distances to the nearest major road, freight route, and railroad; percentage of developed land; number of industrial facilities within 2 km of residences; and population density. Ordinal logistic regression was used to estimate the associations between the covariates of interest and the odds of PCB detection in each site separately. Total PCB levels [all congeners < maximum practical quantitation limit (MPQL) vs at least one congener ≥ MPQL to < median concentration vs at least one congener > median concentration] were positively associated with either percentage of developed land [odds ratio (OR) range 1.01-1.04 for each percentage increase] or population density (OR 1.08 for every 1000/mi(2)) in each site. The number of industrial facilities within 2 km of a home was associated with PCB concentrations; however, facility type and direction of the association varied by site. Our findings suggest that outdoor sources of PCBs may be significant determinants of indoor concentrations.

Exposure to priority organochlorine contaminants in the Italian general population. Part 2

Concentrations of 36 polychlorinated biphenyl (PCB) congeners were measured in serum of 372 Italian residents of general population living in Novafeltria, Pavia, and Milan. Total PCB level differed significantly between these sites ( p < 0.0001) with median concentrations of 836.50, 1354.57, and 2062.08 pmol/g lipid, respectively. However, there is no evidence for the difference in distribution of total PCB levels by genders. Total dioxin-like PCBs differed significantly ( p < 0.0001) between the sites (median 109.78, 50.88, and 166.99 pmol/g lipid, respectively) and genders of Novafeltria and Pavia ( p = 0.011 and 0.009, respectively). PCB 138, 153, 170, and 180 differed significantly between the places of residence ( p < 0.0001) with higher values in Milan population. In the overall population, total PCB and PCB 138, 153, 156, 170, and 180 correlated positively with age (correlations range between 0.320 and 0.569, p < 0.0001). In Novafeltria, the correlations ranged between 0.545 and 0.670, and in Pavia, the correlations ranged between 0.516 and 0.666. In Milan, correlations with age range between 0.327 and 0.417 for total PCB and congeners 138, 153, and 180. With an exception of PCB 170, there was no evidence of significant difference in the distribution of most abundant PCB congeners and total PCB across the body mass index categories.

Polychlorinated Biphenyls, Glycaemia and Diabetes in a Population Living in a Highly Polychlorinated Biphenyls-Polluted Area in Northern Italy: a Cross-sectional and Cohort Study

Conflicts of interests: the authors declare no potential conflict of interests.

Polychlorinated biphenyls in human hair at an e-waste site in China: composition profiles and chiral signatures in comparison to dust

We analyzed the polychlorinated biphenyls (PCBs) in human hair collected from an electronic waste (e-waste) recycling area in southern China and compared their composition profiles and chiral signatures to those of workplace and domestic dust. The PCB concentrations showed significant age dependence in dismantling workers' hair but not in residents' hair. Among residents, PCB concentrations decreased in the following order: elderly people>students>pre-school children>adults. The PCB homologue and congener profiles of the workers' hair were similar to those of the workplace dust. However, the PCB homologue profile of the residents' hair was clearly different from that of the domestic dust. The chiral congener CB95 generally exhibited a racemic or near-racemic composition in both hair and dust, with enantiomer fractions (EFs) ranging from 0.485 to 0.525 in hair and from 0.479 to 0.504 in dust. The EFs of CB132 in dust (0.477-0.513) were closer to a racemic chiral signature than those in hair (0.378-0.521), but this difference was not significant. Our results suggest that the chiral signature of PCBs may be a better tool than the PCB composition profile for identifying the external and internal sources of organic contaminants in human hair. Further measurements of chiral PCB signatures in hair and blood from the same individuals are needed to identify the external and internal sources of PCBs in human hair.

Polychlorinated biphenyls in serum, liver and adipose tissue of subjects with hepatocellular carcinoma living in a highly polluted area

Brescia (North Italy) is located in a highly industrialized area with diffuse environmental pollution by polychlorinated biphenyls (PCBs) and with a high incidence of hepatocellular carcinoma (HCC). We aimed to investigate the concentration of PCBs congeners in serum, liver and adipose tissue of patients with HCC living in this area. We enrolled prospectively 101 HCC incident cases. Lipid-adjusted PCBs concentration of single congeners and total PCBs concentration, computed as the sum of 24 PCBs congeners, were measured in the serum of all subjects and in the liver and abdominal fat of 59 HCC cases undergoing surgery. A high correlation was found between PCBs serum and liver (Spearman r=0.79), serum and fat (r=0.91), and liver and fat (r=0.75) concentrations. Serum PCBs concentration in HCC patients did not vary according to demographical, clinical or epidemiological variables, apart from age, as PCBs concentration increased linearly with the subject's age. This study confirms that serum lipid-adjusted PCBs concentration is a valid measure of PCBs body storage and is highly correlated with PCBs concentration detected in other biological samples.

Occupational exposure to PCDDs, PCDFs, and PCBs of metallurgical workers in some industrial plants of the Brescia area, northern Italy

BACKGROUND

The study was carried out in order to respond to public concern on the occupational exposure of metallurgical workers to highly toxic PCDDs, PCDFs, and PCBs in the area of the city of Brescia, northern Italy.

OBJECTIVES

The study investigated the effects on the haematic burden of occupational exposures to the aforesaid contaminants in different work environments, attempting to establish causal relationships and providing indications for occupational health preventive measures.

METHODS

Chemical concentrations were measured in blood serum of "professionally exposed" (PE) and "not professionally exposed" (NPE) subjects. NPE subjects included industrial administrative employees, Brescia inhabitants, and remote rural people.

RESULTS

The central tendency indexes of contaminant cumulative concentrations were higher in PE than in NPE samples (for the mean values: PCDDs+PCDFs, 22.9 vs. 19.5 pgWHO-TEQ(1997)/g lb; DL-PCBs, 26.0 vs. 23.6 pgWHO-TEQ(1997)/g lb; PCDDs+PCDFs+DL-PCBs (TEQ(TOT)), 48.9 vs. 43.1 pgWHO-TEQ(1997)/g lb; Σ(6)[NDL-PCBs], 427 vs. 401 ng g(-1)lb); however, no statistical differences were detected at P=0.05. A significant difference for PCDDs+PCDFs and TEQ(TOT) was observed as the NPE data were progressively reduced to those of the remote rural people. The existence of a differential occupational exposure due to different environments was detected by applying the factor analysis to congener-specific data (analytical profiles).

CONCLUSIONS

Findings indicate that metallurgical workers may be exposed to PCDD, PCDF, and PCB more than the general population, in particular due to non-negligible contributions to exposure from workplace ambient air. Findings also suggest that an improvement of preventive measures may be required to avoid chemical overexposure in certain metallurgical workplaces. To identify exposure groups, the DL- and NDL-PCB analytical profiles seemed to be more sensitive to environmental exposure sources/pathways than those of PCDDs and PCDFs.

Polychlorinated biphenyls and cancer: an epidemiological assessment

Polychlorinated biphenyls (PCBs) are toxic and persistent chemicals produced between 1930s and 1980s primarily for insulating fluids in heavy-duty electrical equipment in power plants, industries, and large buildings. They persist in the environment and accumulate in plants and animals, and have been classified as probable carcinogens to humans. We performed a systematic review and meta-analysis of scientific literature on the relationship between PCB exposure and human cancer. Two cohorts of people highly exposed to PCBs through ingestion of contaminated rice oil and some cohorts of occupationally exposed workers failed to show a definite increase in total cancer mortality and provided inconsistent results regarding single cancers. Several cohort and case-control studies investigated the association between PCBs and specific cancers, showing an association between PCB serum levels and non-Hodgkin lymphomas (NHL), with a summary odds ratio of 1.5 (95% confidence interval: 1.1-1.7), but no consistent results for the other cancer sites and types. In conclusion, this review provides some evidence for the role of PCBs in the development of NHL, although the inconsistent results of studies performed on highly polluted people and occupationally exposed workers do not allow a firm conclusion to be drawn.

Serum concentrations of persistent organic pollutants (POPs) in the inhabitants of a Sicilian city

BACKGROUND

Polychlorinated biphenyls (PCBs) and organochlorine pesticides are common environmental contaminants that have been associated with human health problems.

OBJECTIVES

To assess serum concentrations of several organochlorine contaminants in general population living in a city with an ancient agricultural tradition and to identify possible exposure sources in Sicily.

METHODS

A cross-sectional study was conducted on 101 individuals. Each participant answered a face-to-face questionnaire submitted by well-trained personnel and provided a serum sample which was analyzed for the concentrations of PCBs, HCB, HCHs and DDTs by using gas-chromatography coupled with mass spectrometry.

RESULTS

HCB, p,p'-DDE, PCB 138, PCB 153 and PCB 180 were detected in more than 80% of the study participants. The ng g(-1) lipid median concentrations were: 18.6 for HCB; 175.1 for p,p'-DDE; 22. for PCB 138; 32.5 for PCB 153 and 23.0 for PCB 180. PCB 153 and PCB 138, PCB 138 and PCB 180, PCB 153 and PCB 180, and p,p'-DDE and HCB showed a high correlation each other (p<0.05). HCB and p,p'-DDE concentrations were significantly higher in subjects >49 years old (adj-p=0.03 in 50-69 years old and adj-p<0.001 in >69 years old, respectively) whereas PCB 138, PCB 153 and PCB 180 concentrations were higher in males (adj-p=0.03), in subjects >69 years old (adj-p=0.04) and in current smokers (adj-p=0.04).

CONCLUSIONS

The present study shows that serum concentrations of organochlorine compounds detected in subjects living in a small Sicilian city with ancient agricultural tradition are similar to those found in subjects living in urban areas of other countries. However, further investigations are needed to compare data from rural/urban areas in the same country, assessing correlations between serum concentrations of several chemical compounds and potential health effects in general population.

Assessment of the daily intake of 62 polychlorinated biphenyls from dietary exposure in South Korea

The dietary intake of polychlorinated biphenyls (PCBs) was estimated using the sum of 62 PCB congeners (∑(62)PCBs), including seven indicator PCBs and 12 dioxin-like PCBs, in the South Korea. In this study, 200 individual food samples belonging to 40 different foodstuffs were investigated to estimate the distribution of PCB congeners in five sampling cities. PCB exposure was estimated using Korean dietary habits as established by the National Health and Nutrition Examination Survey (NHANES). The PCB concentrations in rice, the most frequently consumed food in Korea, was relatively low in whole food samples. The mean PCB levels measured in fish were the highest in this study, but each fish is consumed in relatively small amounts by the general population. Therefore, the daily dietary intake should also be considered with regard to human exposure to PCBs, especially with the consumption of contaminated foods. Dioxin-like PCB levels were also calculated using TEF values that were established in 2005. The average levels (pg TEQ/g) were 0.0002 for rice and 0.0098 for fish. The dioxin-like PCBs accounted for a relatively small percentage of the total PCBs, compared to previous studies. According to our research, the health risks associated with exposure to PCBs could be estimated using the tolerable daily intake (TDI) of the general population.

Common classification schemes for PCB congeners and the gene expression of CYP17, CYP19, ESR1 and ESR2

BACKGROUND

Reliable techniques to measure polychlorinated biphenyl (PCB) congeners make the clearer definition of their effects on human health possible. Given that PCBs are classified as endocrine disrupters, we sought to explore the expression of some key genes involved in sex steroid metabolism.

OBJECTIVES

To examine common classification schemes of PCB congeners and determine whether exposure to groups classified by mechanism of action alter the gene expression (GE) of CYP17, CYP19, and ESR1 and ESR2.

METHODS

GE and exposure to various classifications of lipid-adjusted PCB congeners were examined in 139 daughters of the Michigan Fisheaters' Cohort. Using mixed models analyses and adjusting for age, menopausal status, and current use of oral contraceptives and hormone replacement therapy, GE data were regressed on exposure to PCB congener groupings based on mechanism of action.

RESULTS

Three novel findings are elucidated: first, that up-regulation of CYP19 expression is associated with exposure to PCB groupings containing dioxin-like, potentially anti-estrogenic, immunotoxic congeners, including PCB IUPAC #74, #105, #118, #138, #156, #157, #158, #167, and #170 from this cohort. Second, that exposure to similar congeners (PCB IUPAC #105, #156, #157, #158, and #167 in this cohort) but using a classification based solely on hormonal mechanisms of action is associated with increased expression of ESR2. Third, that increased expression of CYP17 is of borderline significance when associated with exposure to PCB IUPAC #118, #138, and #156.

CONCLUSIONS

These findings are both counter-intuitive and intriguing. Rather than exhibiting anti-estrogenic effects alone, they suggest that these congeners up-regulate the major enzyme involved in estrogen synthesis and tend to confirm previous findings of links between AhR and ER signaling pathways. Replication of these findings, expansion of the number of genes examined, exploration of mixtures of environmental chemicals, and subsequent study of health outcomes in a larger cohort are future priorities.

Gene expression and inducibility of the aryl hydrocarbon receptor-dependent pathway in cultured bovine blood lymphocytes

The exposure to dioxin-like (DL) compounds, an important class of persistent environmental pollutants, results in the altered expression of target genes. This occurs through the binding to the aryl hydrocarbon receptor (AhR), the subsequent dimerization with the AhR nuclear translocator (ARNT), and the binding of the complex to DNA responsive elements. A number of genes are up-regulated, including, among others, the AhR repressor (AHRR) and several biotransformation enzymes, such as the members of CYP1 family and NAD(P)H-quinone oxidoreductase (NOQ1). The expression and the inducibility of the above genes were investigated in mitogen-stimulated cultured blood lymphocytes from cattle, which represent a notable source of DL-compound human exposure through dairy products and meat. As assessed by real-time PCR, all the examined genes except CYP1A2 and NQO1 were detected under basal conditions. Cell exposure to the DL-compounds PCB126 or PCB77 in the 10(-6)-10(-9)M concentration range resulted in a 2-4-fold induction of CYPIA1 and CYP1B1, which was antagonized by α-naphthoflavone or PCB153. This study demonstrates for the first time the presence and inducibility of the AhR pathway in easily accessible cells like bovine peripheral lymphocytes and prompts further investigations to verify whether similar changes could occur under in vivo conditions.

Persistent organochlorine compounds in fetal and maternal tissues: evaluation of their potential influence on several indicators of fetal growth and health

Some organochlorine compounds, such as polychlorinated biphenyls (PCBs), have a tendency to bioaccumulate in humans and predators at the top of the food chain. We have recently confirmed the transplacental transfer of these compounds and the present study has been designed on the same material with the aim of investigating their potential health effects on newborns from 70 pregnant women, resident in a Northern Italy industrial town. Organochlorine compounds [namely, p,p'-dichlorodiphenyltrichloroethane (p,p'-DDT), p,p'-dichlorodiphenyldichloroethene (p,p'-DDE), hexachlorobenzene (HCB), and PCBs] have been analyzed both in cord and maternal serum, placenta, and maternal subcutaneous adipose tissue by GC-MSD. p,p'-DDT levels in the adipose tissue resulted significantly (p<0.05) related to birth length. Mothers of neonates born by preterm programmed caesarean delivery showed significantly (p<0.005 for both) higher serum p,p'-DDE serum concentrations and p,p'-DDT levels in the adipose tissue, as compared to mothers delivering at term.

Polychlorinated biphenyls and non-Hodgkin's lymphoma: a case-control study in Northern Italy

BACKGROUND

Polychlorinated biphenyls (PCBs) have been hypothesized to increase the risk of non-Hodgkin lymphoma (NHL), although conclusive evidence is still lacking. High levels of PCBs were found in soil in some areas close to a PCB-producing factory in Brescia, North Italy. We conducted a population-based case-control study among residents of the town to investigate the possible association between PCB pollution and NHL in this area.

METHODS

We included both incident and deceased NHL cases, and a random sample of the town residents as controls, frequency matched to cases as regards age and gender. Exposure to PCBs was estimated on the basis of the lifetime residential history of cases and controls in four different areas of the town-A, B and C (polluted areas) and D (control area).

RESULTS

A total of 495 cases (287 incident cases) and 1467 controls were enrolled. Positive associations were found between NHL and having resided for at least 10 years in the area A, the most polluted area (odds ratio, OR=1.8; p=0.02) and for having resided in any of the polluted areas considered together (A+B+C) (OR=1.4; p=0.08). However, no associations were evident for having resided 20 years or longer in the polluted areas or when analyzing the association with each subject's main residence in his/her lifetime.

CONCLUSION

This study provides some evidence for an association between PCB exposure and NHL, though results should be considered with caution in the absence of individual biological measures of exposure.

Background levels of polychlorinated biphenyls in the population of the Canary Islands (Spain)

Polychlorinated biphenyls (PCBs) are persistent and toxic compounds that have been detected in human serum or tissues worldwide. The objective of our study was to determine serum PCB levels in a representative sample of the general population of the Spanish Archipelago of the Canary Islands (607 serum samples from subjects aged between 6 and 75 years) in order to establish the main causes of this contamination and to evaluate the potential risks posed by these chemicals on the population through the use of toxicity equivalence to dioxins (TEQs). PCB congeners (28, 52, 77, 81, 101, 105, 114, 118, 123, 126, 138, 153, 156, 157, 167, 169, 180, and 189) were measured by gas chromatography-mass spectrometry (GC/MS). Our results showed that PCB residues were found in 76% of serum samples analyzed, with the congeners 153 and 180 being the most frequently detected and having the highest median values (21.8 and 6.7 ng/g lipid, respectively). Serum levels of non-dioxin-like PCBs increased with age, body mass index (BMI), urban habitat, and smoking. The median concentration of the sum of PCBs considered as markers of environmental contamination by these chemicals (M-PCBs) was 46.4 ng/g lipid. Levels of the sum of dioxin-like PCBs (DL-PCBs) were 48.5 ng/g lipid in the 95th percentile, and were also positively associated with age. As a consequence, age seemed to be positively associated with TEQs levels, reaching values as high as 58.6 pg/g lipid in the serum samples from oldest people. Our results indicate that the inhabitants of the Canary Archipelago show levels of PCB contamination lower than other populations present on the Spanish mainland, as well as many populations from developed countries. Nevertheless, as these compounds may induce adverse health effects even at very low doses, our findings should be considered by local Public Health authorities in order to establish measures for diminishing the exposure of the population of these islands to PCBs.

Association of caffeine consumption and smoking status with the serum concentrations of polychlorinated biphenyls, dioxins, and furans in the general U.S. population: NHANES 2003-2004

Smoking appears to enhance the body's clearance of dioxins and dioxin-like polychlorinated biphenyls (PCB) by inducing CYP1A2 activity based on studies with a limited number of participants. This hypothesis was evaluated by using data from National Health and Nutrition Examination Survey. Specifically, adult participants were identified and the sums of their serum lipid-adjusted concentrations of 12 polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDD/PCDF) congeners, 33 PCB (total), 26 non-dioxin-like PCB, and 6 mono-ortho (dioxin-like) PCB were determined. In addition to evaluating the association of smoking, the association of caffeine consumption and the interaction between them was evaluated. Data analysis included regression models that were fitted with age, gender, race/ethnicity, and body mass index (BMI). R(2) varied from 34.8 to 66%. Smokers had significantly lower concentrations of total PCDD/PCDF than nonsmokers. New to this study, a siginificant interaction between caffeine consumption and smoking for total PCB was found. When caffeine was consumed less than once a day, smokers had higher concentrations of total PCB than nonsmokers. However, when caffeine was consumed at least once a day, smokers had lower concentrations than nonsmokers. A significant interaction between age and caffeine consumption frequency for each of the PCB groups was also observed. The differences in concentration between younger and older age groups were greater when caffeine was consumed at least once a day than when caffeine was consumed less frequently. Smoking and caffeine consumption need to be considered in the interpretation of human biomonitoring data because they appear to affect the serum concentrations of these chemicals.

The impacts of organochlorines and other persistent pollutants on thyroid and metabolic health

High prevalence of thyroid and metabolic disorders has been repeatedly observed in the population living in the area of eastern Slovakia highly polluted by a mixture of PCBs, DDE and HCB since about 50 years ago. Among thyroid disorders, increase of thyroid volume as measured by ultrasound volumetry may be suggested as one of notable findings which appeared possibly related to increased OCs levels and to autoimmunity signs (e.g. positive thyroperoxidase antibodies in blood and/or hypoechogenicity image obtained by ultrasound), while some participation of individual susceptibility and also of immunogenic effect of OCs and iodine in this iodine replete country cannot be excluded. Another notable finding has been the increase of blood FT4 and TT3 positively related to high PCBs level. Such increased FT4 level has been found associated with TSH level in hyperthyroid range in about 2% of examined population from polluted area. High prevalence of thyroid autoimmune disorders strongly supported the assumption on impaired immune system and thus also on presumably increased prevalence of other autoimmune disorders in highly exposed population. In addition, markedly increased prevalence of prediabetes and diabetes significantly related to major OCs (PCBs, DDE and HCB) levels and accompanied by increasing level of cholesterol and triglycerides has been observed. The observations also suggested a role of prenatal exposure to OCs in the development of several adverse health signs (e.g. increased prevalence of thyroid antibodies, impaired fasting glucose level, increased thyroid volume, decreased thymus volume, decreased neurobehavioral performance, increased hearing and dental disorders) in young generation born to highly exposed mothers in polluted area.

Occurrence and distribution of polycyclic aromatic carbons in sludges from wastewater treatment plants in Guangdong, China

In this study, the occurrence and distribution of polycyclic aromatic hydrocarbons (PAHs) were investigated in six sludge samples collected from Guangdong Province, China. Concentrations of PAHs varying from 2,534.1 to 6,926.6 microg kg(-1) (dry sludge) were observed in three municipal wastewater treatment plants with phenanthrene (Phe), fluoranthene, and pyrene being the main compounds. In addition, 682.6 microg kg(-1) PAHs were detected in one sludge sample from a food processing plant, with fluorene, Phe, and chrysene being the main components. No PAHs were detected in sludge samples obtained from two cosmetic plants. The levels and distributional characteristics of PAHs, polychlorinated biphenyls (PCBs), and polycyclic musks (PMs) from the samples were also compared. The results of this comparison indicated that petrochemical refineries and road traffic played important roles in the PAH loads in sludge, while PMs primarily originated from domestic wastewater and industrial wastewater from cosmetic plants. Finally, the presence of 98.8 microg kg(-1) PCBs in sludge suggested diffusional emission sources from electrical components containing PCBs.

Distribution of persistent organochlorine pollutants in maternal and foetal tissues: data from an Italian polluted urban area

This study was designed to evaluate both levels and distributions of organochlorine pollutants in placenta and other maternal-foetal tissues, from women resident in an Italian highly industrialized urban area with demonstrated PCB pollution. To this end, 30 polychlorinated biphenyl congeners (PCBs), p,p'-dichlorodiphenyltrichloroethane (p,p'-DDT), p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) and hexachlorobenzene (HCB), were determined in placenta, both maternal and cord blood serum and adipose tissue of Caucasian pregnant women (n=70) undergoing to programmed caesarean delivery. Median placental concentrations of PCBs, p,p'-DDE and HCB (0.89 ng g(-1), 0.63 ng g(-1) and 0.19 ng g(-1) on wet tissue weight basis, respectively), were lower than previously published data. p,p'-DDT could be detected in most of adipose tissue samples, but very rarely in the other compartments. Distributions of investigated compounds in biological matrices showed significant relationships, confirming their transplacental transfer. It is worthy of note that HCB tended to be transferred more easily from maternal to foetal tissues. Maternal serum levels of these pollutants can allow a reliable estimation of organochlorine compound body burden, and can be useful markers of prenatal exposure, given their relationships with placental and umbilical cord serum levels.