Association between Total and Individual PCB Congener Levels in Maternal Serum and Birth Weight of Newborns: Results from the Chiba Study of Mother and Child Health Using Weighted Quantile Sum Regression

Maternal exposure to polychlorinated biphenyls (PCBs) during pregnancy is associated with a low birth weight; however, the congener-specific effects of PCB congeners are not well defined. In this study, we used maternal serum samples from the Chiba Study of Mother and Child Health (C-MACH) cohort, collected at 32 weeks of gestational age, to analyze the effects of PCB congener exposure on birth weight by examining the relationship between newborn birth weight and individual PCB congener levels in maternal serum (n = 291). The median total PCB level in the serum of mothers of male and female newborns at approximately 32 weeks of gestation was 39 and 37 ng g−1 lipid wt, respectively. The effect of the total PCB levels and the effects of PCB congener mixtures were analyzed using a linear regression model and a generalized weighted quantile sum regression model (gWQS). The birth weight of newborns was significantly associated with maternal exposure to PCB mixtures in the gWQS model. The results suggest that exposure to PCB mixtures results in low newborn birth weight. However, specific impacts of individual PCB congeners could not be related to newborn birth weight.

Passive-Sampler-Based Bioavailability Assessment of PCB Congeners Associated with Aroclor-Containing Paint Chips in the Presence of Sediment

This is the first investigation of the bioavailability of PCBs associated with paint chips (PC) dispersed in sediment. Bioavailability of PCB-containing PC in sediment was measured using ex situ polyethylene passive samplers (PS) and compared to that of PCBs from field-collected sediments. PC were mixed in freshwater sediment from a relatively uncontaminated site with no known PCB contamination sources and from a contaminated site with non-paint PCB sources. PC < 0.045 mm generated concentrations in the PS over one order of magnitude higher than coarser chips. The bioavailable fraction was represented by the polymer-sediment accumulation factor (PSAF), defined as the ratio of the PCB concentrations in the PS and organic carbon normalized sediment. The PSAF was similar for both field sediments. The PSAFs for the field sediments were ~ 50–60 and ~ 5 times higher than for the relatively uncontaminated sediment amended with PC for the size fractions 0.25–0.3 mm and < 0.045 mm, respectively. These results indicate much lower bioavailability for PCBs associated with PC compared to PCBs associated with field-collected sediment. Such information is essential for risk assessment and remediation decision-making for sites where contamination from non-paint PCBs sources is co-located with PCB PC.

Combination of methods of thermal and radiation treatment of sediments associated with PCBs – the Delor type

An efficient method of burning polychlorinated biphenyls (PCBs) is often used to remove the environmental burden of PCBs. However, combustion produces toxic dioxins and furans (PCDD/F), so residents are increasingly rejecting this method. The heat treatment (HT) method does not burn PCBs but evaporates it from sediments. Even in this process, PCDD/Fs are formed to a lesser extent, which are destroyed by radiation processing (RP) following the HT. At the same time, the RP method degrades PCB congeners down to biphenyls, which decompose easily in the environment. A block assembly of a complex synergistic combination of equipment for methods of thermal (HT) and radiation (RP) destruction of PCBs in sediments is proposed. The efficacy of this complex was preliminarily determined at a level of 70-fold reduction in PCB concentration in sediments. To achieve a higher reduction factor in the concentration of PCBs, possible procedures for optimizing the settings of individual devices of this complex are presented.

Inhalation Exposure to PCB from Contaminated Indoor Air—How Much Is Absorbed into the Blood?

Polychlorinated biphenyls (PCBs) were used in many construction products until their banning in the 1970s and 1980s. Nonetheless, exposure to PCBs from contaminated indoor air is still an important public health issue. The aim of our study was to estimate the contribution of PCB congeners in indoor air to the levels of PCBs in human blood. We analyzed all 209 PCB congeners in the blood of 35 individuals exposed to PCBs from contaminated indoor air. For each individual, we measured the six marker indicators PCB28, PCB52, PCB101, PCB138, PCB153 and PCB180 in indoor air at the workplace. Statistically significant correlations between PCB-contaminated indoor air and the existence of the sum of mono-, di-, tri-, tetra- and pentachlorinated biphenyls (∑PCB1–127) in the blood of the exposed individuals were found. We quantified the proportions of PCBs that are absorbed into the blood via inhalation of contaminated indoor air. Inhalation of PCBs from contaminated indoor air, especially in children, adolescents and younger adults, may lead to PCB blood burdens that are higher than general PCB background levels or in approximately the same range.

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.

Efficient simultaneous removal of heavy metals and polychlorobiphenyls from a polluted industrial site by washing the soil with natural humic surfactants

We evaluated the effectiveness of natural organic surfactants such as humic acids (HA) from lignite to simultaneously wash heavy metals (HM) and polychlorobiphenyls (PCB) from a heavily contaminated industrial soil of northern Italy. Supramolecular HA promote in solution a micelle-like structure, where recalcitrant apolar organic xenobiotics are repartitioned from surfaces of soil particles during soil washing process. Concomitantly, the HA acidic functional groups enable a simultaneous complexation of HM. A single soil washing with HA removed 68 and 75% of PCB congeners for 1:1 and 10:1 solution/soil ratios, respectively. The same HA washing simultaneously and efficiently removed a cumulative average of 47% of total HM, with a maximum of 57 and 67% for Hg and Cu, respectively. We showed that washing a highly polluted soil with HA solution not only is an effective and rapid soil remediation technique but also simultaneously removes both HM and persistent organic pollutants (POP). Soil washing by humic biosurfactants is also a sustainable and eco-friendly technology, since, contrary to synthetic surfactants and solvents used in conventional washing techniques, it preserves soil biodiversity, promotes natural attenuation of unextracted POP, and accelerates further soil reclamation techniques such as bio- or phytoremediation.