Blood Levels Of Polychlorinated Biphenyls Research Articles

Systematic investigation of organochlorine pesticides and polychlorinated biphenyls blood levels in Greek children from the Rhea birth cohort suggests historical exposure to DDT and through diet to DDE

The blood levels of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) have been thoroughly investigated in Greek children from the Rhea birth cohort study. This investigation aimed to assess exposure levels, explore their possible relationship with children's age and sex, and indicate potential sources of exposure. Exposure patterns and common sources of PCBs and OCPs were analyzed using bivariate and multivariate statistics.A total of 947 blood samples from study participants were analyzed for OCP and PCB exposure, with 375 samples collected at 4 years old, 239 at 6.5 years old, and 333 at 11 years old. Elevated levels of DDE were observed in 6.5-year-old children compared to corresponding levels in other European countries. Higher levels of DDE were found in 4-year-old children, with the lowest concentrations in the 11-year-old group. The DDT/DDE ratio was consistently less than 1 among all the examined subjects. These results indicate exposure to DDT and DDE both in utero and through breastfeeding and dietary intake. For the entire cohort population, the highest concentration was determined for PCB 28, followed by PCBs 138, 153, and 180. The sum of the six indicator PCBs implied low exposure levels for the majority of the cohort population. Spearman correlations revealed strong associations between PCBs and OCPs, while principal component analysis identified two different groupings of exposure. DDE exhibited a correlation with a series of PCBs (153, 156, 163, 180), indicating a combined OCP-PCB source, and an anticorrelation with others (52, 28, 101), implying a separate and competing source.

Effect of dioxin-related compounds on oral pigmentation in patients affected by the Yusho incident

Background/aimToxins such as polychlorinated biphenyls (PCBs) and dioxins dramatically affect patients even decades after exposure. Patients with Yusho, a condition caused by exposure to PCBs and dioxins, have diverse mental and physical complaints, even though it is almost 50 years since the Yusho incident. Oral pigmentation is one of the major symptoms in Yusho patients. Patients and methodsA total of 183 participants in the Yusho health study were examined. Oral examinations, including recording the prevalence of oral pigmentation, were performed by two oral surgeons. Demographic and clinical characteristics, including blood concentration of PCB and 2,3,4,7,8-pentachlorodibezofuran (2,3,4,7,8-PeCDF), which are the major causes of Yusho, were obtained from the results of recent surveys conducted by the Yusho Study Group. ResultsThe mean serum PCB and 2,3,4,7,8-PeCDF levels of the 183 Yusho patients were 1.59 ± 1.25 ppb and 29.0 ± 42.9 pg/g lipid, respectively. There was a significant correlation between the levels of PCB and 2,3,4,7,8-PeCDF (r = 0.64, p < 0.01). The rate of oral pigmentation in Yusho patients (25.7%) was significant higher than among potential victims of Yusho (13 of 183, 7.1%) (p < 0.05). ConclusionThe prevalence of oral pigmentation was still significantly higher in Yusho patients, even 50 years after exposure, although blood PCB levels have decreased in that time.

Toxicokinetics of Chiral PCB 136 and Its Hydroxylated Metabolites in Mice with a Liver-Specific Deletion of Cytochrome P450 Reductase.

Exposure to polychlorinated biphenyls (PCBs) has been implicated in adverse human health effects, including developmental neurotoxicity. Several neurotoxic PCBs are chiral and undergo atropisomeric enrichment in vivo due to atropselective metabolism by cytochrome P450 enzymes. Here we study how the liver-specific deletion of the cytochrome P450 reductase ( cpr) gene alters the toxicokinetics of 2,2',3,3',6,6'-hexachlorobiphenyl (PCB 136) in mice. Male and female mice with a liver-specific deletion of cpr (KO) and congenic wild-type (WT) mice were exposed to a single oral dose of racemic PCB 136 (6.63 mg/kg). Levels and chiral signatures of PCB 136 and its hydroxylated metabolites were determined 1-48 h after PCB exposure in whole blood. Blood levels of PCB 136 were typically higher in M-WT compared to F-WT mice. At the later time points, F-KO mice had significantly higher PCB 136 levels than F-WT mice. 2,2',3',4,6,6'-Hexachlorobiphenyl-3-ol (3-150), 2,2',3,3',6,6'-hexachlorobiphenyl-4-ol (4-136), 2,2',3,3',6,6'-hexachlorobiphenyl-5-ol (5-136), and 4,5-dihydroxy-2,2',3,3',6,6'-hexachlorobiphenyl (4,5-136) were detected in blood, with 5-136 and 4-136 being major metabolites. At later time points, the sum of HO-PCB (∑HO-PCB) levels exceeded PCB 136 levels in the blood; however, higher ∑HO-PCB than PCB 136 levels were observed later in KO than WT mice. PCB 136 and its major metabolites displayed atropisomeric enrichment in a manner that depended on the time point, sex, and genotype. Toxicokinetic analysis revealed sex and genotype-dependent differences in toxicokinetic parameters for PCB 136 atropisomers and its metabolites. The results suggest that mice with a liver-specific deletion of the cpr gene can potentially be used to assess how an altered metabolism of neurotoxic PCB congeners affects neurotoxic outcomes following exposure of the offspring to PCBs via the maternal diet.

The role of heavy metals and polychlorinated biphenyls (PCBs) in the oncogenesis of head and neck tumors and thyroid diseases: a pilot study

Previous literature has highlighted the mechanisms of molecular toxicity induced by substances such as arsenic, cadmium, chromium, nickel, lead, barium and PCBs. The research was carried out on 20 volunteers, all the patients gave their consent to the research: the aim of the study was to evaluate the presence of metals and PCBs in these different matrices (blood and hair), correlating the biochemical data to pathological conditions present, and also to the area in which patients resided. Various quantitative determinations were carried out on samples of blood and hair for 14 heavy metals and on blood samples for 12 PCBs. For the 11 patients the results indicated that blood levels for half of the 14 displayed heavy metals measured considerably higher compared to the reference values, whilst the levels measured in hair evidenced some positive values significantly higher than the maximum reference. Of the 12 PCBs assayed in blood some showed higher positive values compared to the maximum tabular reference (although there is no clear reference quantified in the WHO-2005 report). In the 9 healthy patients heavy metals in the blood were within the expected target range, with those showing positive results (≤ 3 out of 14 heavy metals for each patient) having values only slightly higher than the reference maximum. The levels of 14 heavy metals measured in hair were below thresholds, and levels for the 12 PCBs measured in blood showed negativity or positivity with values close to the minimum benchmarks. The analyses carried out on biological matrices have uncovered important and significant differences between healthy and unhealthy subjects, both qualitative and quantitative differences with respect to heavy metals and PCBs. All patients with head and neck cancer enlisted for the study had heavy metal and PCB blood levels at least twice the maximum reference level. The levels of heavy metals in hair were at least double the maximum reference. In contrast, all healthy volunteers enrolled showed no significant levels for either metals or PCBs.

Pollutants and diet influence carotenoid levels and integument coloration in nestlings of an endangered raptor

Carotenoid-based traits or ornaments, such as yellow-red integuments (feathers, beaks, legs or eye-rings) displayed by birds, play key roles in social communication by reliably advertising an individual's quality or health. In some species, these traits are displayed not only by adults but also by nestlings, and function in parent-offspring communication or sibling competition by advertising an individual's physical or physiological condition. Pollutants such as organochlorine compounds (OCs) could have disruptive effects on the coloration of these traits, thereby interfering with communication processes. Such effects have been reported in adult birds, but are still largely unknown for nestlings. Here we investigated associations between polychlorinated biphenyl (PCB) and dichlorodiphenyltrichloroethane (DDT) blood-levels, circulating carotenoid levels and the yellow-orange coloration of the cere and tarsi of wild Black Harrier Circus maurus nestlings, a scarce raptor endemic to southern Africa. As carotenoid pigments must be acquired through the diet, we also tested for an effect of dietary composition. The orangeness-purity of cere and tarsi coloration positively correlated with circulating carotenoid levels, and increased with both nestling age and the proportion of birds consumed in the diet. Circulating carotenoid levels and the orangeness-purity of colored integuments were unrelated to blood PCB levels, although the brightness of integuments (i.e. lack of pigmentation) increased with PCB levels. Nestlings with more DDT had lower levels of circulating carotenoids and reduced carotenoid-based coloration (i.e. higher hue and lower saturation, reflecting a yellow rather than orange and less intense color, respectively). Together, our results are consistent with the hypothesis that OC contaminants, in particular DDT, may disrupt carotenoid-based signaling in exposed nestlings.

Polychlorinated Biphenyls (PCBs) in Human Hair and Serum from E-Waste Recycling Workers in Southern China: Concentrations, Chiral Signatures, Correlations, and Source Identification.

Hair is increasingly used as a biomarker for human exposure to persistent organic pollutants (POPs). However, the internal and external sources of hair POPs remain a controversial issue. This study analyzed polychlorinated biphenyls (PCBs) in human hair and serum from electronic waste recycling workers. The median concentrations were 894 ng/g and 2868 ng/g lipid in hair and serum, respectively. The PCB concentrations in male and female serum were similar, while concentrations in male hair were significantly lower than in female hair. Significant correlations between the hair and serum PCB levels and congener profiles suggest that air is the predominant PCB source in hair and that hair and blood PCB levels are largely dependent on recent accumulation. The PCB95, 132, and 183 chiral signatures in serum were significantly nonracemic, with mean enantiomer fractions (EFs) of 0.440-0.693. Nevertheless, the hair EFs were essentially racemic (mean EFs = 0.495-0.503). Source apportionment using the Chemical Mass Balance model also indicated primary external PCB sources in human hair from the study area. Air, blood, and indoor dust are responsible for, on average, 64.2%, 27.2%, and 8.79% of the hair PCBs, respectively. This study evidenced that hair is a reliable matrix for monitoring human POP exposure.

Polychlorinated Biphenyls and Cancer: Are Telomeres to Blame?

The accumulating epidemiological evidence of elevated cancer risk and mortality in individuals exposed to polychlorinated biphenyls (PCBs) led to their recent classification as human carcinogen by the International Agency for Research on Cancer (IARC) (International Agency for Research on Cancer (IARC), 2015). However, the mechanisms by which PCBs are linked to cancer are still unclear. In this issue, Scinicariello and Buser (Scinicariello, 2015) conducted a study of the association between leukocyte telomere length (LTL) and PCB blood levels in a nationally representative sample of the civilian US adult population using data from the National Health and Nutrition Examination Survey (NHANES). The authors showed that higher PCB blood levels were associated with longer LTL, and hypothesized that there could be a link to PCB-related carcinogenesis. A separate study reported similar relationships between LTL and PCB blood levels in a subset of NHANES participants (Mitro et al., 2015). However, a small study of healthy Koreans (Shin et al., 2010) showed that this relationship was only present at low PCB levels. In contrast, short LTL has been associated with a number of environmental or occupational exposures including particulate matter, black carbon, benzene, toluene, polycyclic aromatic hydrocarbons, N-nitrosamines, pesticides, and lead (reviewed in Zhang et al., 2013), all of which may contribute to PCB blood levels. Telomere shortening in response to chemical exposures may be explained, at least in part, by the induction of an oxidative stress DNA damage response (Zhang et al., 2013). Telomeres, the long (TTAGGG)n nucleotide repeats and an associated protein complex at chromosome ends, are essential for maintaining chromosomal stability. They shorten with each cell division and therefore are markers for cellular replicative capacity, cellular senescence, and aging. Telomere shortening and chromosomal instability has been described at early stages of carcinogenesis, suggesting a role of telomere dysfunction in cancer initiation (Ferguson et al., 2015). Cancer epidemiology studies have shown relationships with short LTL, but differences by cancer site and study design were noted. In a meta-analysis of 27 reports (Wentzensen et al., 2011), short LTL was associated with cancer risk, primarily in case–control studies (OR = 2.9 in case–control studies vs. 1.2 in prospective studies). This suggests that short LTL is a disease marker rather than a risk factor. Recently, a large study linked long LTL to melanoma risk (Iles et al., 2014). The spectrum of cancers associated with long LTL is not clear yet, but suggested to include lung and Non-Hodgkin's lymphoma (NHL). It is of interest that cutaneous melanoma and possibly NHL are the main cancers associated with excess risk in PCBs exposed individuals (International Agency for Research on Cancer (IARC), 2015), suggesting a possible contribution of LTL in PCB-related carcinogenesis. The large sample size, the national representation, and the wealth of collected information NHANES offers are among the strengths of this study. On the other hand, the cross-sectional design restricted its ability to establish a causal inference between LTL, PCB exposure, and cancer risk. The one-time measurement of PCB blood level and LTL may not reflect the full spectrum of the association. Information on the duration and dose of exposure to PCBs would have been useful (reviewed in Zhang et al., 2013) Short-term exposure to ambient particulate matter was associated with long LTL, while longer exposures were associated with short LTL. Exposure dose in relation to LTL was noted in other environmental exposures. For example, exposure to low dose of arsenic resulted in telomerase overexpression and telomere elongation in cord blood cells, while exposure at large doses suppressed telomerase, shortened telomeres, and induced apoptosis. A recent study (Andreotti et al., 2015) evaluating the association between LTL and pesticide exposure suggested a differential effect on LTL in long-term versus recent exposures for certain pesticides. While LTL may present a good surrogate for telomere length in other tissues, it is not clear how good of a surrogate it is for tissues affected by chemical exposures. Measuring telomere length in organs directly affected by PCB exposure, and comparing this to LTL may explain the role telomeres may play in PCB-related carcinogenesis. Also, LTL measurement obtained by quantitative polymerase chain reaction (qPCR) assay may be affected by the cell composition of the sample since telomere length differs by peripheral blood cell subtype. Using a leukocyte cell-type specific TL measurement assay such as flow FISH may provide better insights into such association. Important considerations in epidemiological studies of telomere length are discussed in details elsewhere (Bodelon et al., 2014). In conclusion, the mechanism behind PCB-related carcinogenesis is still unknown. The similarity between cancer sites associated with long LTL, and cancers linked with PCBs provides an interesting hypothesis to test. A large prospective study with serial LTL and PCBs level measurements is required to better understand this relationship.

Assessment of the polychlorinated biphenyls (PCBs) levels in soil samples near an electric capacitor manufacturing industry in Morelos, Mexico

In Mexico, polychlorinated biphenyls (PCBs) were principally used as heat transfer chemicals in electric transformers and capacitors as well as hydraulic fluids and lubricants in heavy electrical equipment since the early 1940s. However, although PCBs have been banned in Mexico, their past and present improper disposal has resulted in environmental contamination. Therefore, the aim of this study was to evaluate the PCBs levels in soil samples in the immediate area of an electric capacitor manufacturing industry, which was established several years ago in Alpuyeca, Morelos, Mexico. To confirm the presence of PCBs, surface soil samples (1–5 cm in depth) were collected from the vicinity of the industry. We determined the concentrations of 40 PCB congeners in soil samples using gas chromatography/mass spectrometry. The total PCBs levels in the soil samples ranged from 6.2 to 108460.6 μg kg−1. Moreover, when we analyzed the results of the congeners (non-dioxin-like PCBs and dioxin-like PCBs), the levels of non-dioxin-like PCB congeners ranged from 5.7 to 103469 μg kg−1 and the levels of dioxin-like PCB congeners ranged from 0.5 to 4992 μg kg−1. Considering that soil is an important pathway of exposure in humans, analysis of PCBs levels in blood (as a biomarker of exposure) is necessary in individuals living in Alpuyeca, Morelos.

Relationship between food intake &amp; geographic information from questionnaire and blood PCB level in birth cohort study

Background: Our previous studies indicated that blood PCB (polychlorinated biphenyl) level was affected by factors regarding age and past delivery experience. In Japan Environment and Children’s Study (JECS, a Japanese national birth cohort study), a detail questionnaire survey regarding food intake and geographic (residences’ address) information has been conducted. Aims: The aim of this study was to examine the relationship between maternal blood PCB level and sea food intake/geographic information from the JECS’s questionnaires. Methods: We measured the serum total PCB from pregnant women in Chiba Prefecture, who participated in the JECS in 2012. The number of the subjects was 352 (age: 17-43). Total PCB was analyzed from serum by using a gas chromatograph equipped with a packed column and electron capture detector (Packed column GC/ECD). Using Spearman's rank correlation coefficient, Fisher's exact test and Geographic Information System (GIS), we examined the relationship between maternal blood PCB level and sea food intake/geographic information. Results: PCB was detected from 95% of nulliparous (average was 0.30 ± 0.14 ng/g-wet) and 90% of multiparas (average was 0.26 ± 0.12 ng/g-wet). The blood PCB level increased with age. We found strong association (P&lt;0.01) between blood PCB level and intake of bonito, yellowtail, saury, cod roe and tuna. Comparing the blood PCB levels between coastal area and other areas, a tendency was found that the PCB level in the region where many fishermen live in coastal area was higher than other areas. Conclusion: Our present study indicated the possibility that sea food intake and geographic information in the questionnaire can sample the high exposure group to PCB and POPs. The answers to the questionnaires can be used to detect potential high risk group in a cost and time effective manner in a large scale cohort study. (The current data of JECS is not the final data but tentative and limited data of Chiba Prefecture)

Polychlorinated biphenyl levels in the blood of Japanese individuals ranging from infants to over 80 years of age

Individuals’ exposure to various persistent organic pollutants (POPs), including polychlorinated biphenyls (PCBs), and its adverse health effects have been a cause of concern. We measured blood PCB concentrations from samples taken from 507 Japanese individuals ranging from infants to those over 80 years of age. The blood PCB levels increased with age for both male (Spearman’s r = 0.69, p < 0.001) and female (Spearman’s r = 0.70, p < 0.001) participants. Adult men and nulliparous women showed similar increases with age. However, the PCB levels of multiparous women were lower than those of nulliparous women in their thirties (p = 0.005), probably because the PCBs were transferred from the mothers to their children during pregnancy and lactation. Among infants (<2 years of age), some had as high levels of accumulated PCB levels as those in adults >30 years of age. In some cases, the PCB levels were over 0.8 ng/g wet weight, similar to levels observed in adults over 50 years of age. In the future, it will be necessary to do research on the health of the children who are exposed by high concentration level of POPs.

Polychlorinated biphenyls (PCBs) in Africa: a review of environmental levels

Several studies have shown an increase in PCB sources in Africa due to leakage and wrongly disposed transformers, continuing import of e-waste from countries of the North, shipwreck, and biomass burning. Techniques used in the recycling of waste such as melting and open burning to recover precious metals make PCBs contained in waste and other semivolatile organic substances prone to volatilization, which has resulted in an increase of PCB levels in air, blood, breast milk, and fish in several regions of Africa. Consequences for workers performing these activities without adequate measures of protection could result in adverse human health effects. Recent biodegradation studies in Africa have revealed the existence of exotic bacterial strains exhibiting unique and unusual PCB metabolic capability in terms of array of congeners that can serve as carbon source and diversity of congeners attacked, marking considerable progress in the development of effective bioremediation strategies for PCB-contaminated matrices such as sediments and soils in tropical regions. Action must be taken to find and deal with the major African sources of these pollutants. The precise sources of the PCB plume should be pinned down and used to complete the pollutant inventories of African countries. These nations must then be helped to safely dispose of the potentially dangerous chemicals.

Correlations of PCBs, DIOXIN, and PBDE with TSH in Children's Blood in Areas of Computer E-waste Recycling

Objective To study correlations of polychlorinated biphenyls (PCBs), DIOXIN, and polybrominated diphenyl ethers (PBDE) with thyroid stimulating hormone(TSH) in children, and assess the impact on children's health. Methods Three hundred and sixty nine children aged from 6 to 8, including 195 from Luqiao, the computer E-waste recycling area, and 174 from Longyou, the control area, were selected for this investigation to elucidate the correlation of PCBs, DIOXIN, and PBDE with TSH in children's blood samples. The children had a physical examination and their blood levels of PCBs, DIOXIN, PBDE, and TSH were detected after sample collection. Results In the E-waste recycling area, the contents of PCBs, PBDE, DIOXIN, and TSH in the blood samples of children were 484.00±84.86 ng·g −1 lipid weight, 664.28±262.38 ng·g −1 lipid weight, 26.00±19.58 ng·g −1 lipid weight and 1.88±0.42 μIU/mL (serum) respectively, while in the control area, the PCBs, PBDE, DIOXIN, and TSH contents were 255.38±95 ng·g −1 lipid weight, 375.81±262.43 ng·g −1 lipid weight, 39.64±31.86 ng·g −1 lipid weight, and 3.31±1.04 μIU/mL respectively. Conclusion The health status of children in the control area are better than that in the contaminated area. Among children who are exposed to persistent organic pollutants, the pollutant content increases significantly in their serum, and the distribution of TSH levels in their bodies are also affected.

Alteration of infant attention and activity by polychlorinated biphenyls: Unravelling critical windows of susceptibility using physiologically based pharmacokinetic modeling

Pre- and postnatal exposure to polychlorinated biphenyls (PCBs) can impair behavioural function in animal models at doses within the range at which humans are commonly exposed. Yet, epidemiologic studies conducted in the US and Europe are inconsistent with regard to the developmental effects of lactational exposure to these chemicals. This inconsistency may be due to limitations in the current methodological approaches for assessing postnatal exposure to PCBs. Our study used a physiologically based pharmacokinetic (PBPK) model to simulate blood PCB levels during specific pre- and postnatal periods and to evaluate the relation of those levels to infant behaviour. A previously validated PBPK model was used to simulate infant blood PCB-153 levels at delivery and on a month-by-month basis during the first year of life for Inuit infants enrolled in a longitudinal birth cohort. Infant behaviour was assessed using the Behaviour Rating Scales (BRS) of the Bayley Scales of Infant Development (BSID-II) at 11 months of age and video coding of inattention and activity measured during the administration of the mental development subscale of the BSID-II. The estimated pre- and postnatal PCB exposure measures predicted significant increases in inattention and activity at 11 months. Whereas inattention was related to prenatal exposure, activity level, measured by non-elicited activity, was best predicted by postnatal exposure, with the strongest association obtained for simulated PCB levels during the 4th month of life. These findings are consistent with previous reports indicating PCB-induced behavioural alteration in attention and activity level. Simulated infant toxicokinetic profiles for the first year of life revealed windows of susceptibility during which PCBs may impair infant attention and activity.

Temporal changes in PCB and DDE levels among a cohort of frequent and infrequent consumers of Great Lakes sportfish

A variety of environmentally persistent contaminants of the Great Lakes Basin are able to bioaccumulate in the aquatic food chain and pose a threat to the health and reproductive success of people and wildlife that depend on locally caught fish as a source of dietary protein. Exposure to polychlorinated biphenyls (PCBs) and 1,1-bis(4-chlorophenyl)-2,2-dichloroethene (DDE) has been linked to higher rates of cancer, reproductive problems, and endocrine disorders. To investigate the effects of exposure to persistent contaminants of the Great Lakes Basin, the health departments of five Great Lakes states formed a health-assessment consortium. Between 1988 and 1994, the consortium collected demographic and fish consumption information from 2548 licensed charter boat captains, 182 anglers, and 1667 referents. Between 1994 and 1995, a subset of 619 participants in this study provided additional fish consumption information and donated blood samples that were analyzed for PCBs and DDE. Follow-up studies conducted between 2001 and 2005 re-assessed fish consumption rates and blood levels of PCBs and DDE in 293 of these individuals. While there was a trend for increasing overall fish consumption among most participant groups, sportfish and Great Lakes sportfish consumption decreased significantly in the captains over the study period. Serum DDE concentrations, which were highest in men in the captain and angler groups, declined in 90% of study participants. Mean DDE levels fell from 5.6 to 3.2 μg/L. Total PCB levels declined in 80% of participants with the mean concentration falling from 4.2 to 2.8 μg/L. Annual declines in serum DDE and PCB concentrations averaged 4.6% and 3.5%, respectively.

Persistent Organic Pollutants: Not Finished Yet

Although polychlorinated biphenyls (PCBs) were banned in the United States in 1977, they persist in the environment. These bioaccumulative chemicals can damage the immune, reproductive, endocrine, and nervous systems. When looking for environmental sources of PCBs, scientists generally measure dietary intake from fish, meat, and milk. However, older wood floor finishes that harbor PCBs may present an underestimated route for exposure, finds Ruthann Rudel, a toxicologist at the nonprofit Silent Spring Institute in Newton, Massachusetts. Animal studies show that PCBs decrease the size of the thymus gland and suppress antibody production and immune responses. People exposed to PCBs can suffer from skin rashes, changes in blood and urine that can indicate liver damage, irregular menstrual cycle, lowered immune response, fatigue, and headache. In children, poor cognitive development is reported. The International Agency for Research on Cancer classifies PCBs as probable human carcinogens. From 1999 to 2001, Rudel and her colleagues monitored 89 indoor pollutants linked to breast cancer in 120 homes on Cape Cod, where breast cancer rates are among the highest in Massachusetts. As reported 13 September 2003 in Environmental Science & Technology, detectable levels of PCBs were found in about a third of the residences, and two houses had exceedingly high levels of PCBs in air and dust. Five years later, Rudel revisited these two houses to measure air and dust concentrations of the congeners PCB52, PCB105, and PCB153 as well as occupants’ blood levels of 10 congeners measured in 1999–2002 as part of the National Health and Nutrition Examination Survey (NHANES). Air and dust levels remained exceptionally high, with dust values ranging from 21 to 190 μg/g—up to 20 times higher than reported in other studies of indoor PCB exposure. Three of the occupants, all of whom had lived in their homes for more than a decade, showed elevated blood levels of PCBs as high as 1,520 ng/g, placing them in the top 5% of people living in the United States. A fourth occupant, who had lived in her house for only six months, had a blood level of 179 ng/g. The study is published as volume 7, article 2 (2008) of the online journal Environmental Health. None of the occupants ate enough fish to account for the high blood levels of PCBs. “We were really stumped,” says Rudel. Then the homeowner with the highest PCB levels recalled that 50 years earlier he had finished his wood floors with high-gloss “Fabulon” varnish. In the 1950s and 1960s, Fabulon was a popular coating sold nationwide to give floors a “bowling-alley shine.” A now-discontinued reference manual, Clinical Toxicology of Commercial Products, confirmed that Fabulon contained PCBs between 1950 and 1969. Before being banned, PCBs were not only added to varnishes but also to caulk, paint, linoleum, and ceiling tiles, where they served as stabilizers, sealants, and adhesives. The same homeowner had sanded one of his floors just before Rudel returned to collect samples for the latest study. However, the floors in the other house had not been refinished in years. Rudel suspects, but has not confirmed, that the floors may be giving off PCBs, with sanding releasing even higher levels of dust packed with PCBs. She hopes to conduct further research—such as whether a peak time for exposure occurs when sanding off PCB-laced finishes, or whether carpets later laid over finished wood floors limit airborne exposure—that might shed light on safer ways to remove PCBs. What can homeowners do, pending further information? “I’m not happy about how little I can tell people,” Rudel admits. Foremost, she advises not sanding old wood floors. PCB analysis is expensive, and Rudel knows of no laboratories that service homeowners. However, some floor-finishing businesses offer a dustless sanding process that pumps toxic dust into outdoor tanks. “Rudel certainly found an unrecognized source of PCBs that underscores the importance of inhalation as an underappreciated but important source of exposure,” says David Carpenter, a public health physician at the University at Albany, State University of New York. The results add to a growing body of awareness that building materials can be a significant source of PCBs indoors. “The assumption that PCBs stay put simply is not true,” Carpenter says.

Is There a Need to Revise Health Canada’s Human PCB Guidelines?

This article assesses if there is a need to revise Health Canada's polychlorinated biphenyl (PCB) guidelines for whole blood given that plasma is typically favoured over whole blood for analysis, technological advancements in analytical methods have occurred, and the congener profiles of PCBs in the environment continue to change due to degradation and re-compartmentalization. Canadian epidemiological and exposure studies within the last 11 years were examined in order to determine the dominant method of PCB reporting and the human tissues or fluids analyzed. In all but one study, PCBs were analyzed on a congener basis. In the cases where an Aroclor equivalency was reported, the result was calculated using an Aroclor estimation equation based on several PCB congeners. To date, a wide variety of tissues and fluids are still being analyzed; however, only one study performed the analysis using whole blood, the basis of Health Canada's guidelines. Additionally, congener profiles in the environment are changing due to degradation and re-compartmentalization; therefore, guidelines should reflect this change. The reporting of whole blood PCB levels in Canada is a rare practice, and reporting PCBs solely as an Aroclor mixture can result in false non-detection; however, the Health Canada guidelines are based on Aroclor 1260 levels in whole blood. PCB congener analysis by gas chromatography/mass spectroscopy results in greater accuracy with greater sensitivity and limit of detection for the samples when compared to gas chromatography alone. Further, Aroclor equivalency can be estimated from congener analysis results. No other nation has yet prescribed PCB guidelines in human fluids or tissues; this is likely due to the uncertainty associated with PCB health risk assessment. Given the findings, whole blood PCB guidelines must be revised in order to reflect advances in the medical sciences.

Fish from industrially polluted freshwater as the main source of organochlorinated pollutants and increased frequency of thyroid disorders and dysglycemia

In a certain area of Michalovce district in East Slovakia, heavy industrial pollution by polychlorinated biphenyls (PCBs) developed in 1955-1984 and very high PCB levels in environmental and human samples are still persisting. Recently, a total of 2045 adults from this and the surrounding background pollution area have been examined using questionnaire data, thyroid volume by ultrasound (ThV), urinary iodine and serum levels of 15 PCB congeners, hexachlorobenzene (HCB), 2,2'-2-bis(4-chlorobiphenyl)-1,1-dichloroethylene (DDE), 2,2'-bis(4-chlorophenyl)-1,1,1-trichloroethane (DDT), alpha-, beta- and gamma-hexachlorocyclohexane (HCH), thyrotropin (TSH), free thyroxine (FT4), anti-thyroperoxidase antibodies (TPOab) and fasting glucose. As based on our previous findings of strikingly high level of PCBs in fish from high pollution area (e.g. mean level of 375430 ng/g lipid) and considerably lower, but still relatively high level in background pollution area (e.g. mean PCB level of 5150 ng/g), the information on the frequency of fish meals and approximate annual consumption of fish from local waters was obtained by questionnaires. The association of contaminated fish consumption with very high blood levels of PCBs, DDE and HCB and increased ThV as well as with increased frequency of positive TPOab, high values of FT4 and impaired fasting glucose (IFG) was found. These associations were also confirmed in 16 marital pairs from high pollution area with very high PCB level in both members associated with high fish consumption. It was concluded that, due to persistent heavy pollution of waters, soil and food chain namely by PCBs, but also by pesticides (e.g. DDE and HCB) resulting from their previous extensive use in agriculture, the fish from local waters still remains the most important source of these toxic pollutants which results in considerable adverse health effects.

Enantioselective disposition of PCB 136 (2,2′,3,3′,6,6′‐hexachlorobiphenyl) in C57BL/6 mice after oral and intraperitoneal administration

Studies of xenobiotic disposition in rodents often employ experimental designs using differing routes of administration. In an effort to investigate the effects of route of administration on enantioselective disposition of xenobiotics, a chiral polychlorinated biphenyl (PCB), racemic PCB 136, was administered as a single dose (50 mg/kg body weight) to male or female C57BL/6 mice either orally or via intraperitoneal injection. Mice were sacrificed after either 3 or 6 days, and blood and organs were collected for PCB analysis. Intraperitoneal injection of PCB 136 produced statistically higher PCB levels in blood and organs than did the oral administration. Tissue levels were higher after 3 days than those after 6 days. Enantioselective analysis showed that (+)-PCB 136 was enriched in most organs, with the most pronounced enrichment found in the liver and the brain of animals dosed orally or by intraperitoneal injection, respectively. Significantly higher retained enantiomeric fractions of PCB 136 were found in the oral treatment groups compared with those found in intraperitoneal treatment groups, possibly as a result of the lower PCB levels in oral treatment groups. Therefore, the choice of administration route may well have implications for the enantioselective disposition of PCB 136 and other chiral substances.

Women’s Health: Endometriosis and PCB Exposure

Vol. 114, No. 7 EnvironewsOpen AccessWomen’s Health: Endometriosis and PCB Exposure Carol Potera Carol Potera Search for more papers by this author Published:1 July 2006https://doi.org/10.1289/ehp.114-a404aCited by:2AboutSectionsPDF ToolsDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InReddit Endometriosis may be related to exposure to persistent pollutants such as polychlorinated biphenyls (PCBs), according to research published in the May 2006 issue of Chemosphere. This gynecological disorder linked to infertility afflicts 10% of U.S. women of reproductive age. Researchers measured blood PCB levels in women undergoing laparoscopy for suspected endometriosis or other gynecological conditions. Higher levels of PCBs were detected in women with histologically confirmed endometriosis compared with controls.Toxicologist Elena De Felip of the Istituto Superiore di Sanità in Rome and her colleagues measured 11 PCB congeners that are most abundant in human tissue. In 80 women aged 20 to 40, the sum of all congeners was 1.6 times higher in the 40 women diagnosed with endometriosis than in controls. Three congeners, PCBs 138, 153, and 180, were particularly higher in women with endometriosis. These three congeners have been reported to have estrogenic activity and to interfere with hormone-regulated processes.PCBs have been used since the 1930s, mainly in electrical equipment. Although no longer manufactured, these persistent chemicals accumulate in the food chain; today meat, fish, eggs, and milk are chief sources of PCBs. But diet seems unable to explain the difference in PCB levels detected in the two groups of women, since “the dietary habits of the women were basically the same,” says De Felip.De Felip suspects that differences in how women detoxify and eliminate PCBs from the body may explain the disparity. These processes are mediated by polymorphic enzymes; therefore, she says, differences in toxicokinetic activity may represent the basis for the higher concentrations detected in women with endometriosis and may also be related to higher or lower susceptibility to that condition.Studies of PCBs and endometriosis face several limitations. Researchers typically measure only a few widespread congeners that are selected because of their toxicological activities, including an association with cancer shown in animal models. “So we’re only getting part of the picture,” says Germaine Buck Louis, chief of the Epidemiology Branch at the National Institute of Child Health and Human Development.In a study described in the January 2005 issue of Human Reproduction, Buck’s team measured 62 congeners in 84 women undergoing laparoscopy. Levels of 4 antiestrogenic congeners were 3.77 times higher in women diagnosed with endometriosis than in controls. “We don’t fully understand the role of estrogenic and antiestrogenic PCBs,” she says, but complex interactions of many PCBs as well as other chemicals may be involved in developing endometriosis.Recent advances in PCB detection methods allow more congeners to be measured at lower concentrations. “Women with endometriosis may have low levels of a particular congener not found in [other women],” says Louis. Moreover, breastfeeding reduces PCB levels in women, so women without endometriosis may have lower blood levels because they become pregnant and breastfeed more often. “There’s no ideal comparison group for endometriosis studies,” says Louis, and “there are no easy answers.”FiguresReferencesRelatedDetailsCited By Wang J, Hülck K, Hong S, Atkinson S and Li Q (2011) Accumulation and maternal transfer of polychlorinated biphenyls in Steller Sea Lions ( Eumetopias jubatus ) from Prince William Sound and the Bering Sea, Alaska, Environmental Pollution, 10.1016/j.envpol.2010.09.022, 159:1, (71-77), Online publication date: 1-Jan-2011. Trenck K, Schilling F and Schmidt D (2007) Bioindikation mit WanderfalkenBioindication with peregrine falcons: New results from Baden-Wuerttemberg, Umweltwissenschaften und Schadstoff-Forschung, 10.1065/uwsf2007.03.187, 19:2, (75-82), Online publication date: 1-Apr-2007. Vol. 114, No. 7 July 2006Metrics About Article Metrics Publication History Originally published1 July 2006Published in print1 July 2006 Financial disclosuresPDF download License information EHP is an open-access journal published with support from the National Institute of Environmental Health Sciences, National Institutes of Health. All content is public domain unless otherwise noted. Note to readers with disabilities EHP strives to ensure that all journal content is accessible to all readers. However, some figures and Supplemental Material published in EHP articles may not conform to 508 standards due to the complexity of the information being presented. If you need assistance accessing journal content, please contact [email protected]. Our staff will work with you to assess and meet your accessibility needs within 3 working days.

Complete blood cell counts and blood chemistry in Yusho

Because of their lipophilic nature, polychlorinated biphenyls (PCBs) bioaccumulate in the food chain and their residues have been detected in foods. Consequently, they accumulate readily in the human body. Reports suggest that PCB blood levels remain constant or increase. Little, however, is known about the long-term hazardous effects of PCBs and dioxins on human health. Yusho is a type of food poisoning caused by PCBs and dioxins that contaminated rice bran oil. We analyzed blood samples of the Yusho patients from 1986 to 2002, and studied changes in blood cell counts, blood chemistry and tumor markers. A population of 1041 patients was divided into patient and control groups based on the diagnostic criteria established for Yusho and participant's blood polychlorinated quarterphenyl (PCQ) levels. In total, 1666 blood and 1652 urine samples from 374 patients in the patient group (PCQ levels = 0.1 ppb), and 373 blood and 302 urine samples from 151 people in the control group (PCQ levels < 0.02 ppb) were analyzed. Blood levels of PCBs, PCQs, polychlorinated dibenzo- p -dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were determined, and we analyzed their correlation with the data of complete blood cell counts, blood chemistry and urinalysis . Blood analyses, blood chemistry and urine values in Yusho patients were not significantly different from those in the control group 34 years after the Yusho incident. PCBs, PCQs or PCDFs may, however, affect hematogenesis, serum potassium, serum phosphorus, protein metabolism and creatine kinase metabolism because these parameters had slight but significant correlations with the levels of PCBs, PCQs or PCDFs. Exposure to PCBs and the related organochlorine compounds should be avoided.