Polybrominated Biphenyls Research Articles

Modulated covalent organic frameworks with higher specific surface area for the ultrasensitive detection of polybrominated biphenyls

Controllable construction of covalent organic frameworks (COFs) is fascinating, and full elucidations on the relationships between their microstructures and adsorption performance for persistent organic pollutants (POPs) are imperative and desirable, yet challenging. Herein, the 2,5-dimethoxybenzaldehyde (DB) has been first employed as a modulator to construct COFs with higher specific surface area and enhanced hydrophobicity under the mild conditions, after competing with the building blocks of 2,5-dimethoxyterephaldehyde (DMTP) and 1,3,5-tris(4-aminophenyl)benzene (TAPB). These TAPB-DMTP-DB COFs have been further fabricated as solid phase microextraction (SPME) coatings with uniform morphology and comparative thickness, to investigate their enrichment capacities for POPs systematically. In particular, the DB-modulated COF demonstrated outstanding enrichment factors (4400–11360) for polybrominated biphenyls (PBBs). Moreover, ultrasensitive analytical method has been developed based on the DB-modulated COF-coated fiber and gas chromatography-mass spectrometry (GC–MS), with low limits of detection (0.04–0.28 ng/L), wide linear range (0.25–5000 ng/L), and satisfactory reproducibility, realizing the precise quantifications of ultra-trace PBBs in environmental aqueous samples.

A probabilistic hazard and risk assessment of exposure to metals and organohalogens associated with a traditional diet in the Indigenous communities of Eeyou Istchee (northern Quebec, Canada)

Hunting, trapping, and fishing are part of an Indigenous lifestyle in subarctic Canada. However, this lifestyle may be a route of exposure to contaminants and may pose a risk for the people who rely on a subsistence diet. Monte Carlo simulations for the chemical concentration of eight game species and one fish species were carried out by randomly sampling 10,000 samples from the contaminant measures for each species. We then calculated a probabilistic non-carcinogenic hazard quotient or carcinogenic risk values to estimate the human health risk of exposure to contaminants. Of the species examined, ducks were of concern for potential carcinogenic risk. There was a modeled probabilistic 95th-percentile risk associated with the consumption of ducks and polybrominated biphenyl (PBB) congener 153 in boys, women, and men (1.09 × 10−6, 1.57 × 10−6, and 2.17 × 10−6, respectively) and, to a lesser extent, with geese and polychlorinated biphenyl (PCB) congener 153 in men (1.19 × 10−6). Contaminant concentration in the intake rate (food consumption) for PBB congener 153 exposure risk was more important than that for PCB congener 153, where intake rate had greater relevance. The consumption of waterfowl may increase the exposure to organohalogens; however, there are health and wellness benefits associated with the harvesting and consumption of subsistence foods that must also be considered. We recommend follow-up species-specific studies focused on ducks to clarify and elucidate the results in the present study.

Utility of an alternative method (to USEPA Method 1613) for analysis of priority persistent organic pollutants in soil from mixed industrial-suburban areas of Durban, South Africa.

This study evaluates the adequacy of a USEPA Method 1613 alternative analytical method for analysis of persistent organic pollutants (POPs) in soil from the immediate vicinity of industrialized areas in the eThekwini municipal area in South Africa. The objective of this study is in line with the Stockholm Convention Article 11 on research, development, and monitoring. Furthermore, it became imperative to find an alternative analytical procedure to USEPA Method 1613 that could cater to studies conducted in Africa where recent reviews have indicated that most African countries lack the technical and instrumental capacity for performing analysis of dioxin-like compounds according to USEPA Method 1613, which entails the use of high-resolution chromatography and high-resolution mass spectrometry instrumentation. The study aimed to ascertain the utility of an alternative two-dimensional gas chromatography-time of flight mass spectrometry method for analysis of trace-level priority POPs in soil, along with a fast single quadrupole gas chromatography-mass spectrometry method. The analytical methods were applied to the analysis of POPs on soil samples from industrial areas with oil refineries and a pulp and paper manufacturing company, while other samples were collected near the electricity substations and a landfill site. Analytical results showed BDE 209 as the dominant contaminating polybrominated diphenyl ether (concentration ranges from 0.006 to 5.71 ng g-1 ). Polybrominated biphenyls (PBBs) 9, 10, and 49 were the dominant PBBs detected in 78% of the sites tested, although their concentrations were below the limit of quantification (LOQ). Polychlorinated dibenzo-p-dioxins and furans and dioxin-like polychlorinated biphenyls detected could not be quantified above their respective LOQs, indicating that the Durban area has low priority pollutant contamination levels compared to other regions around the world. The methods developed are a starting point thatwill inform considerations for routine evaluation and management of soil contamination, which plays a vital role in environmental management. IntegrEnviron Assess Manag 2023;19:749-762. © 2022 SETAC.

Metabolic changes associated with polybrominated biphenyls and polychlorinated biphenyls in the Michigan PBB registry

Background: Polybrominated Biphenyls (PBBs) and Polychlorinated Biphenyls (PCBs) are endocrine-disrupting chemicals (EDCs). In Michigan, people were exposed to PBBs during a time-limited contamination event in the 1970s and are continuously exposed to PCBs. Using high-resolution metabolomics (HRM), this study aimed to identify biological mechanisms underlying human health effects of PBB and PCB exposure. Methods: HRM profiling was conducted on serum samples from the Michigan PBB Registry collected from a subset of 500 individuals representing both F0 (directly exposed to PBB) and F1 (exposed through parents) generations from 2011 to 2014. This study measured PBB-153 stratified by generation and ƩPCB (PCB-118, PCB-138, PCB-153, and PCB-180) in the total combined subset (as all experienced direct PCB exposure). Metabolite and metabolic pathway perturbation were evaluated using an untargeted HRM workflow. Results: Both exposure measures had high detection levels. Mean levels were 1.75-ng/mL (SD: 13.9) for PBB-153 and 1.04-ng/mL (SD: 0.788) for ΣPCBs. 124 and 86 metabolomic features were significantly associated with PBB-153 in F0 and F1 (p<0.005), respectively. There were 2,861 features associated with ΣPCB (FDR corrected p<0.2). Pathway enrichment analysis revealed perturbations associated with ΣPCB in numerous oxidative stress and inflammation pathways (e.g., carnitine shuttle, glycosphingolipid, and vitamin B9 metabolism). Perturbations associated with PBB-153 in F0 were related to oxidative stress pathways (e.g., pentose phosphate and vitamin C metabolism) and in F1 were related to energy production (e.g., pyrimidine, aminosugars, and lysine metabolism). Authentic chemical standards were used to confirm the chemical identity of 29 metabolites associated with ΣPCB levels and 10 metabolites associated with PBB-153 levels. Conclusions: Our results demonstrated that serum PBB-153 and ΣPCB levels were associated with perturbations in inflammation and oxidative stress-related pathways, which differed when stratified by generation. These findings support future investigations of molecular mechanisms underlying PBB and PCB exposure on health, emphasizing exposure timing.

Birth outcomes associated with paternal polybrominated and polychlorinated biphenyl exposure

In 1973–74, a polybrominated biphenyl (PBB) flame retardant mixture was shipped to Michigan livestock feed mills in place of a nutritional supplement and contaminated the food supply. Following the accident, the Michigan PBB Registry was established to study the long-term health effects of halogenated compounds and is now led by a community-academic partnership. PBB exposure is associated with altered DNA methylation in sperm, which may lead to adverse birth outcomes in children whose fathers have increased levels of serum PBB or polychlorinated biphenyl (PCB). Paternal PBB and PCB levels of men enrolled in the Michigan PBB Registry (n = 155) were analyzed against matched offspring birthweight and gestational age (n = 336). Birthweight and gestational age were dichotomized at the 25th percentile and 37 weeks, respectively, and paternal PBB and PCB levels were examined as continuous measures and divided into tertiles. Associations of offspring birthweight and gestational age with paternal PBB and PCB serum concentrations were modeled using multivariable linear spline and log-risk regression, adjusting for family clustering, paternal health and lifestyle factors, maternal PBB, and PCB serum concentrations, sex, and offspring gestational age (for birthweight). Fathers in the middle and upper PBB and PCB tertiles had increased risks for lowest quartile birthweight compared to the first tertile, with adjusted risk ratios (aRR) = 1.67 (95% CI: 0.93, 2.99) and aRR = 2.06 (95% CI: 1.12, 3.79) for PBB, and aRR = 1.47 (95% CI: 0.79, 2.75) and aRR = 1.34 (95% CI: 0.70, 2.54) for PCB, respectively. Elevated paternal PBB levels were not associated with an increased risk for preterm birth, while PCB levels were associated with a small, but not significant, decrease in gestational age, β = -0.37 (95% CI: -0.76, 0.03) weeks per log unit increase PCB. The findings suggest that increased paternal PBB and PCB levels negatively impact offspring birthweight, and paternal PCB levels may negatively impact gestational age.

Human developmental toxicity mechanism of polybrominated biphenyl exposure and health risk regulation strategy for special populations

Polybrominated biphenyls (PBBs) can bioaccumulate in nature and are toxic to humans. Long-time exposure to PBBs in pregnant women can lead to the birth of an infant with abnormal conditions. Hence, in this study, we used molecular docking, molecular dynamics, Taguchi experimental design, and fractional factorial experimental design to identify the developmental toxicity characteristics of 10 typical developmental toxic pollutants such as PBBs to which humans are frequently exposed. Furthermore, the correlation and sensitivity analyses of molecular developmental toxicity and structural parameters were performed. The molecular key structural parameters of the pollutants affecting human development were screened. Moreover, the supplementary food factors that could alleviate the developmental toxicity of pollutants were screened to develop supplementary food schemes to prevent or alleviate human developmental toxicity in the special population (e.g., pregnant women, infants) exposed to the pollutants. The results showed that the developmental toxicity was controlled by the main effects of the 10 pollutants. Among the 10 pollutants with developmental toxicity, the most significant pollutant with the main effects was PBB-153 (37.06%). In addition, the correlation and sensitivity analyses of the molecular developmental toxicity of the pollutants and structural parameters showed that the total energy value and infrared C–H vibration frequency of the pollutants were significantly correlated with human developmental toxicity. Accordingly, 15 supplementary food cofactors were selected for the Taguchi experiment design, among which the top seven cofactors were designed by fractional factorial analysis. The most significant cofactor that alleviated the developmental toxicity of PBB-153 exposure was the combination of carotene and docosahexaenoic acid (DHA), with an improvement of 17.28%. The combination of carotene and DHA significantly alleviated the effects of toxicity caused by most of the other pollutants, indicating that the selected supplementary food has certain universality. In this study, we developed a method to identify the characteristics of the developmental toxicity of pollutant exposure and developmental toxicity alleviation. Our study provided theoretical support for the regulation strategy of developmental toxicity caused by pollutants such as PBBs.

Control of extreme brominated persistent organic pollutant emissions from start-ups of waste-to-energy incinerators

Unlike chlorinated persistent organic pollutants (Cl-POPs), few studies have investigated the emissions of brominated POPs (Br-POPs), including polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs), polybrominated biphenyls (PBBs), and polybrominated diphenyl ethers (PBDEs), from start-up processes of municipal solid waste incinerators (MSWIs). Presently, there are no studies published on Br-POP control during this period. This study found that start-up processes could contribute to at least 27%, 55%, and 2% PBDD/F, PBB, and PBDE emissions of an entire year of MSWI operations. High PBDD/F and PBDE emission rates were observed at the beginning of the start-up, indicating that control measures should be conducted before or at the beginning of the start-ups. PBBs behaved like Cl-POPs with high emission rates observed at the POP-formation temperature window (250–450 °C). Unlike Cl-POPs, inhibiting adsorptive memory effects by cleaning the accumulated ash was the most effective control strategy for PBDD/F and PBDE emissions, accounting for 72.8% and 51.3% of total reductions, respectively. Contrarily, inhibiting Br-POP formation by cleaning the accumulated ash and shortening the residence time of the flue gas in 250–450 °C contributed to the highest PBB reduction (67.5%). Overall, the control strategies reduced PBDD/F and PBB emissions by >97% and PBDEs by 61%. This study shows that PBDD/Fs and PBDEs behave differently from their chlorinated equivalents and require different control strategies. In conclusion, the control strategies proposed can reduce Br-POP emissions during start-up successfully, and they require no modifications to existing control devices.

Global interlaboratory assessments on PCBs, organochlorine pesticides and brominated flame retardants in various environmental matrices 2017/2019

In support of the United Nations Environment Programme (UNEP) global monitoring plan under the Stockholm Convention contributing laboratories were offered to take part in a series of interlaboratory assessments on persistent organic pollutants (POPs). The results of two rounds of these assessments are reported. The target compounds were polychlorinated biphenyls, organochlorine pesticides, polybrominated diphenylethers, one polybrominated biphenyl and hexabromocyclododecane diastereomers. The matrices distributed were a test solution, fish, sediment, human milk, and air extracts. The number of participants in each round was well over 100, showing the interest of laboratories worldwide. The results showed that many laboratories still struggle to obtain acceptable standard deviations of around 25% for their determinations. In particular for organochlorine pesticides serious improvement in quality is required. Acceptable results were obtained for the air extracts and for the determination of polybrominated diphenylethers in various matrices.

Survey of bioavailable PCDDs, PCDFs, dioxin-like PCBs, and PBBs in air, water, and sediment media using semipermeable membrane devices (SPMDs) deployed in the Hartbeespoort Dam area, South Africa.

A survey of bioavailable polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like PCBs (dl-PCBs), and polybrominated biphenyls (PBBs) from ambient air, water and sediment was performed in the Hartbeespoort Dam area in South Africa, a region where data on highly toxic Stockholm Convention persistent organic pollutants (POPs) is scanty. The sampling was designed to simulate POP bioaccumulation in benthic and aquatic dwelling organisms as well as ambient air for estimation of ecological risk. The objective was to survey the spatiotemporal distribution and fate of bioavailable priority persistent organic compounds in the Hartbeespoort Dam in summer, autumn and winter seasons and to validate the utility of a comprehensive two-dimensional gas chromatography-time of flight mass spectrometry (GCxGC-TOF) method for PCDD/F, PCB, and PBB analysis. The highest detection rates for bioavailable priority POPs were for PCB 77 and PCB 126 which were detected in 15 and 16 of the 22 samples, though the majority of the detections were < LOQ for PCB 77. Overall, PCB 126, PBB 10 and PBB 49 recorded the highest quantified bioavailable concentrations per site in SPMDs deployed in the Hartbeespoort Dam. The SPMDs deployed in air at the Magalies River site in winter recorded the highest toxic equivalency quotient (TEQ) of 29.77pg TEQ SPMD-1. The highest TEQs recorded for SPMDs deployed in the sediment phase were 10.2, 3.3, and 3.2pg TEQ SPMD-1, recorded at the Harbour site in summer, Dam wall in summer and Harbour in winter respectively. In water, SPMDs deployed at the Crocodile River site recorded the highest TEQ of 0.81pg TEQ SPMD-1 in summer. TEQ data shows that air carries significant bioavailable dl-toxicity compared to the water phase, and sediment generally carries the highest dl-toxicity. Detection rates for bioavailable PBBs were generally very low, with < 3 detections being quantified above the LOQ for the majority of the sites. Statistical analysis of TEQs computed at all sites, using AVOVA shows that the dispersion of TEQs in the Hartbeespoort Dam is largely homogenous as the differences between the TEQs were insignificant (p > 0.05).

Analysis of brominated flame retardants in the aquatic environment: a review.

The most common and consequently analysed brominated flame retardants (BFRs) are polybrominated biphenyls (PBBs), polybrominated diphenyl ethers (PBDEs), tetrabromobisphenol A (TBBPA), tetrabromobisphenol S (TBBPS), and hexabromocyclododecane (HBCD). As these persistent organic pollutants are widespread in the environment and have a number of harmful effects on human health, the production and use of most has been banned for several years. The aquatic environment is polluted by these compounds through their deposition from the atmosphere, sewage sludge, wastewater treatment plants, and landfills, and higher levels are found in areas with developed industry and agriculture and near landfills. Each compound also seems to show preference for specific compartments of the aquatic environment, i.e. water, sediment, or aquatic organisms, according to their physicochemical properties. The aim of this review was to take a closer look at the analysis of BFRs, as without reliable analysis we would not be able to determine their levels and distribution across the aquatic compartments and assess human exposure and health risks. Particularly worrying are the health risks associated with PBDEs in fish, whose levels generally exceed the permitted values.

Using In Vitro and Machine Learning Approaches to Determine Species-Specific Dioxin-like Potency and Congener-Specific Relative Sensitivity among Birds for Brominated Dioxin Analogues.

There is a paucity of experimental data regarding dioxin-like toxicity of polybrominated dibenzo-p-dioxins/dibenzofurans (PBDD/Fs) and non-ortho polybrominated biphenyls (PBBs). In this study, avian aryl hydrocarbon receptor 1 (AHR1)-luciferase reporter gene assays were used to determine their species-specific dioxin-like potencies (DLPs) and congener-specific interspecies relative sensitivities in birds. The results suggested that DLPs of the brominated congeners for chicken-like (Ile324_Ser380) species did not always follow World Health Organization toxicity equivalency factors of their chlorinated analogues. For ring-necked pheasant-like (Ile324_Ala380) and Japanese quail-like (Val324_Ala380) species, the difference in DLP for several congeners was 1 or even 2 orders of magnitude. Moreover, molecular docking and molecular dynamics simulation were performed to explore the interactions between the brominated congeners and AHR1-ligand-binding domain (LBD). The molecular mechanics energy (EMM) between each congener and each individual amino acid (AA) residue in AHR1-LBD was calculated. These EMM values could finely characterize the final conformation of species-specific AHR1-LBD for each brominated congener. Based on this, mechanism-driven generalized linear models were successfully built using machine learning algorithms and the spline approximation method, and these models could qualitatively predict the complex relationships between AHR1 conformations and DLPs or avian interspecies relative sensitivity to brominated dioxin-like compounds (DLCs). In addition, several AAs conserved among birds were found to potentially interact with species-specific AAs, thereby inducing species-specific interactions between AHR1 and brominated DLCs. The present study provides a novel strategy to facilitate the development of mechanism-driven computational prediction models for supporting safety assessment of DLCs, as well as a basis for the ecotoxicological risk assessment of brominated congeners in birds.

Electronic waste and their leachates impact on human health and environment: Global ecological threat and management

Electronic waste is an important part of solid waste management around the world. Being a large part of the solid waste, e-waste contains numerous hazardous components in the form of halogenated compounds like polychlorinated biphenyls (PCBs), tetrabromobisphenol A (TBBPA), polybrominated biphenyl (PBB), etc. along with other toxic materials which cause an adverse impact on the plants, microbes and human beings. One of the major toxic components of e-waste are heavy metals (HMs) like As, Cr, Cd, Cu, and Hg, which needs to be handled carefully at the time of dismantling the e-wastes, being managed by informal sector in developing countries compounds the problem, also, the available disposal/treatment technologies of e-waste are inadequate, and they have a direct as well as indirect impact on human health and the environment. This review deals with the quantity of e-waste generated globally and how its different components affect important factors of the ecosystem like soil, plants, microbes, and animals, including humans. This review also deals the recovery of valuable metals using various methods. This review concludes that, there is a quintessential need to replace conventional traditional procedures with futuristic state of the art eco-friendly approaches to manage e-waste. • The e-waste production generation is expected to increase of 4%–5% annually worldwide. • Toxic effect of E-waste leachate to human health and environment is considered widely. • An environmental friendly methods have been expressed for E-wastes management. • Numerous methods for base and precious metals recovery from the e-waste are reviewed. • Biological method for recovery of metals from e-waste is most efficient and cost effective.

Halogenated flame retardants in wild, prey-sized mud carp from an e-waste recycling site in South China, 2006–2016: Residue dynamics and ecological risk assessment

The crude e-waste recycling has been regulated in China since the late 2000s; however, information on the recent levels and the ecological risks of e-waste derived contaminants such as halogenated flame retardants (HFRs) in the e-waste sites are limited. We therefore examined the concentrations of several HFRs in wild, prey-sized mud carps collected from a typical e-waste site in 2006, 2011 and 2016, to understand the exposure dynamics and ecological risk of these chemicals. Several ecological and biological parameters including δ15N, δ13C, body size and lipid content of the fish were also examined, to ensure an overall uniformity of the sample set among the sampling years. Among the HFRs measured, polybrominated diphenyl ethers (PBDEs) were detected at the highest concentrations (contributing >90% to ∑HFRs), followed by Dechlorane Plus (DPs), polybrominated biphenyls (PBBs), and alternative brominated flame retardants (ABFRs). The fish concentrations of ∑PBDEs, ∑PBBs and ∑DPs significantly dropped by 65%, 57% and 53% from 2006 to 2011, and 12%, 74% and 51% from 2011 to 2016, respectively; likely reflecting the positive impact of the environmental regulations on crude e-waste recycling. The ∑ABFRs concentrations were also decreased by 80% from 2006 to 2011, but increased by 127% from 2011 to 2016; suggesting possible fresh input of these novel HFRs in recent years. In addition to the changes in the HFR concentrations, contaminant profiles in the fish were also changed, possibly due to environmental degradation of the HFRs. Despite our conservative method of risk assessment, we found that PBDEs posed an important risk both for the mud carp and for piscivorous wildlife that inhabit the e-waste site.

Detection of Persistent Organic Pollutants in Omental Adipose Tissue from Patients with Diffuse-Gastric Cancer: A Pilot Study.

Simple SummaryThis pilot study reported the observation that great omentum could be analyzed to detect persistent organic pollutants (POPs). Diffuse gastric cancer is an increasing disease that could be associated with pollutants’ exposition. Here, we report a specific POP profile regarding a patient not affected by cancer, nor by diffuse gastric cancer or other abdominal cancers. The widespread presence of a substantial list of POPs (PCDDs/Fs, PCBs, and brominated flame retardants) was found in the omentum from patients with diffuse gastric cancer with minor presence of some organochlorine pesticides.The greater omentum represents a specific adipose tissue resected with gastric surgery for cancer. Diffuse gastric adenocarcinoma (diffuse-GC) is of major relevance among gastric cancers due to its unknown origin, aggressiveness, and metastasis in the peritoneal cavity. We postulated that persistent organic pollutants (POPs) could be detected in the greater omentum. Great omentum from patients with (i) diffuse-GC, or (ii) with other peritoneal metastatic cancer, and (iii) control group without cancer disease were analyzed for the distribution of a large panel of 96 POPs. POPs include polychlorinated dioxins/furans (PCDD/Fs), polychlorobiphenyls (PCBs), polybrominated diphenyl ethers (PBDE), polybrominated biphenyls (PBB), hexabromocyclododecanes, organochlorine pesticides, and polycyclic aromatic hydrocarbons (PAHs). The widespread presence of a substantial list of POPs (PCDDs/Fs, PCBs, and brominated flame retardants) was found in the omentum from patients with aggressive diffuse-GC, with minor presence of some organochlorine pesticides and PAHs at the low analyzed levels. Some chemicals appeared in larger concentrations in diffuse-GC or other cancer groups, including some PCDDs, PCB105, 123, 138, PBDE209, and PBB153. Overall, the present pilot study provides novel information regarding POPs levels in the omental fat, which is an understudied fat depot in terms of POPs load, and diffuse-GC association.

Birth Outcomes Associated with Paternal Polybrominated and Polychlorinated Biphenyl Exposure

BACKGROUND AND AIM: In 1973, polybrominated biphenyl (PBB) flame retardant was shipped to Michigan feed mills in place of a nutritional supplement and contaminated the food supply. Following the accident, the Michigan PBB Registry was established to study the long-term health effects of halogenated compounds, and is now led by a community-academic partnership. PBB exposure is associated with decreased DNA methylation in sperm regulatory elements controlling imprinted genes, which may lead to adverse birth outcomes in children whose fathers have increased levels of serum PBB or polychlorinated biphenyl (PCB), an analogue of PBB. To further understand the impact of paternal exposures on children, we analyzed paternal PBB and PCB levels and premature birth and low birthweight. METHODS: We investigated the outcomes of birthweight and gestational age of offspring whose fathers enrolled in the PBB Registry and provided serum to measure PBB and PCB concentrations. Birth outcomes were determined by linking paternal PBB records to the Michigan vital records. Birthweight and gestational age were dichotomized at the 25th percentile and 37 weeks respectively, and paternal PBB and PCB levels were divided into tertiles. Offspring birthweight and gestational age were modeled against paternal PBB and PCB serum concentrations using log-risk regression, adjusting for clustering, paternal health and lifestyle factors, and offspring sex. RESULTS:Elevated PBB and PCB levels are associated with an increased risk of low offspring birthweight, but not preterm birth. Fathers in the middle and upper PBB and PCB tertiles illustrated increased risk ratios (RR) for low offspring birthweight, RR=1.42 (CI=0.93-2.17) and RR=1.47 (CI=1.03-2.10) for PBB, and RR=1.73 (CI=1.12-2.67) and RR=1.42 (CI=0.84-2.41) for PCB respectively. Elevated PBB and PCB levels illustrated no significant increased risk for preterm birth in the middle and upper tertiles. CONCLUSIONS:These findings suggest increased paternal PBB and PCB levels may negatively impact offspring birthweight. KEYWORDS: Endocrine disrupting chemicals, Birth outcomes, Children's environmental health, Community outreach, Environmental epidemiology

In-utero exposure to polybrominated biphenyl (PBB) and menstrual cycle function in adulthood

BACKGROUND AND AIM: There is evidence that in-utero exposure to PBBs, and similar chemicals, are associated with several adverse reproductive health outcomes including altered pubertal timing; however, less is known about the effects of in-utero exposure to PBBs on menstrual cycle function and reproductive hormone levels in adulthood. METHODS: For this menstrual cycle study, we recruited reproductive-aged women in the Michigan PBB Registry who were not pregnant, lactating, or taking hormonal medications (2004-2014). A total of 42 women who were born after the PBB contamination incident (1973-1974), who were only exposed in-utero, were included in this analysis. We estimated in-utero PBB exposure using maternal serum PBB measurements taken after exposure and extrapolated to time of pregnancy using a PBB elimination model. Women were followed for up to 6 months during which they provided daily urine samples and completed daily diaries. The urine samples were assayed for estrone 3-glucuronide (E13G), pregnanediol 3-glucuronide (Pd3G), and follicle stimulating hormone (FSH). RESULTS:Women in our study were, on average, 27.5 (SD:5.3) years and contributed 4.9 (SD:1.9) menstrual cycles of follow-up. Compared to women with low in-utero PBB exposure (≤1 ppb), women with medium (1.0-3.0 ppb) and high (3.0 ppb) exposure had significantly higher maximum 3-day mean Pd3G levels during the luteal phase. Specifically, the age- and creatinine-adjusted maximum 3-day mean luteal phase Pd3G levels (95% CI) in increasing categories of in-utero PBB exposure were 9.2 (4.6,13.9), 14.8 (11.6,18.0), and 16.1 (12.9,19.3) μg/mg. There were no significant differences in average cycle length, follicular or luteal phase cycle length, bleed length, or creatinine-adjusted E13G or FSH levels by category of in-utero PBB exposure. CONCLUSIONS:Higher exposure to PBB in-utero was associated with increased progesterone levels across the luteal phase, however, most other menstrual cycle characteristics were largely unassociated with in-utero PBB exposure. Given our modest sample size, our results require cautious interpretation. KEYWORDS: Endocrine disrupting chemicals, Reproductive Outcomes, Chemical exposures, Environmental epidemiology, Long-term exposure

Collaborative Research: Partnering with the community to improve the science and its impact

BACKGROUND AND AIM: The Michigan PBB Research Registry consists of ~7,000 people exposed to polybrominated biphenyls (PBB) following its accidental introduction into Michigan’s animal feed. After nearly forty years, the PBB Registry was transferred to Emory University, allowing the research team to engage this community. METHODS: Community engagement (CE) activities were initiated with goals of disseminating research findings to those affected, responding to educational needs, incorporating community input, and facilitating research participation. CE methods include community meetings, where research results are shared with the affected community and questions/concerns are addressed and documented. At the first community meeting, we asked for volunteers for the Citizens Advisory Board (CAB) to guide us in research and engagement efforts. The CAB joined forces with the Pine River Superfund Citizen Task Force, a community advisory group focused on the remediation of the Superfund sites left from the PBB manufacturer, and the Mid-Michigan District Health Department. RESULTS:These efforts have evolved into a community-research partnership, where the community identified research questions, helped develop the research approach, and is an integral part of research decision-making. This partnership has led to significant changes in outreach activities, research protocols, and research priorities: community health concerns were added to surveys, the age range for participation was expanded, and chemical workers/family who were removed from the Registry (1990s) due to multiple exposures were re-enrolled with exposome methods to evaluate their complex exposures. Community concerns regarding multi-generational effects and continued high-levels of PBB body burden led to a multi-generational epigenetics study, a clinical trial aimed at accelerating PBB elimination, and an oral history study documenting the lived experience of those affected using qualitative methods. This work will be translated in an online continuing medical education course for healthcare providers. CONCLUSIONS:The community-research partnership has enhanced the science and its relevancy and potential benefit to the impacted community. KEYWORDS: Community-engaged research, science communication, exposome, environmental epidemiology, environmental justice

Comparison by Race and Ethnicity of Endocrine Disrupting Chemical levels in the U.S. Military

BACKGROUND AND AIM: Prior studies reported racial/ethnic (R/E) differences in serum concentrations of polyhalogenated aromatic hydrocarbons (PHAHs), an endocrine disrupting chemical class including polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), polybrominated biphenyls (PBBs), and organochlorine pesticides (OCPs). We investigated R/E differences in PHAH serum concentrations in members of the U.S. military. METHODS: Serum samples, obtained 1994-2010, for 742 active-duty military personnel were analyzed by ICP mass-spectrometry. We compared serum concentration levels of 14 PCBs, 4 PBDEs, 1 PBB, and 5 OCPs, for which at least 40% of samples had detectable values. We used a multiple imputation method to replace values below the detection limit. Age-adjusted geometric means (aaGMs) of serum concentrations (ng/g-lipid) of these analytes were compared by R/E between the 467 (66.0%) non-Hispanic (NH) whites (reference), 132 (18.6%) NH blacks, 68 (9.6%) Hispanics, and 41 Asians/Pacific Islanders (APIs) (5.8%) using generalized linear models. RESULTS:The mean participant age was 27.3 (SD=7.4) years. Compared to NH whites, NH blacks had higher aaGMs for all PCBs, while Hispanics had lower aaGMs. PBDE aaGMs were generally higher among NH blacks and Hispanics than NH whites; APIs also had lower levels. For OCPs, APIs had the highest levels of dichloro-diphenyl-trichloroethane (DDT). Yet, Hispanics had the highest levels of DDT’s major metabolite, dichlorodiphenyldichloroethylene (DDE). NH blacks had the highest levels of trans-nonachlor and oxychlordane, while NH whites had the highest levels of hexachlorobenzene. Most differences in aaGMs by R/E were statistically significant (p0.05). CONCLUSIONS:This study found differences in serum concentrations of several endocrine disrupting chemicals by R/E among military personnel. Studies are needed to investigate if these differences exist at entry into the military or are associated with military exposures. Disclaimer: The opinions here are the authors’ and do not reflect the official views of the Uniformed Services University or the Department of Defense. KEYWORDS: Endocrine disrupting chemicals, Pesticides, Chemical exposures, Occupational exposures

Polyhalogenated aromatic hydrocarbon exposure mixture and risk of papillary thyroid cancer in active-duty U.S. military: A nested case-control study

BACKGROUND AND AIM: Exposure to endocrine-disrupting chemicals has been implicated in increasing incidence of papillary thyroid cancer (PTC). The evidence of associations between PTC risk and exposure to polyhalogenated aromatic hydrocarbons (PHAHs), including polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs), is largely limited to single-pollutant studies. We aimed to investigate the relationship between a PHAH exposure mixture and PTC risk. METHODS: We conducted a case-control study nested within the Department of Defense (DoD) cohort including 742 histologically-confirmed PTC cases (54% male) diagnosed 2000-2013 and 742 individually-matched controls. PHAHs were measured in pre-diagnostic sera collected 1994-2010. We used quantile g-computation to estimate the joint effect of a PHAH mixture on PTC risk, adjusting for body mass index and military service branch. Quantile g-computation is appropriate for matched case-control study design and allows the direction of weights among mixture components to vary. Our PHAH mixture included 24 lipid-corrected congeners (four PBDEs, 14 PCBs, five OCPs, and one polybrominated biphenyl). RESULTS:Mean age at PTC diagnosis was 35 (± 8) years. On average, serum samples were collected nine years before PTC diagnosis. Overall, a one-quartile increase in the PHAH mixture was non-significantly associated with 11% increase in PTC risk (95%CI=0.81-1.50). PCB-180 and PCB-118 contributed the largest total mixture weights in the positive direction, while PCB-153, PCB-187, and PBDE-100 contributed the largest total mixture weights in the inverse direction. The risk among women was elevated (OR=1.33; 95%CI=0.79-2.23), while it was relatively null among men (OR=0.90; 95%CI=0.60-1.37). CONCLUSIONS:Our study suggests that exposure to a large mixture of ubiquitous environmental pollutants is non-significantly associated with PTC risk in a young active-duty military population. However, that risk may be higher for women than men. Disclaimer: The views expressed here are the authors’ and do not necessarily reflect official policies/positions of USU, the DoD, or the CDC. KEYWORDS: Endocrine disrupting chemicals, Environmental epidemiology, Mixtures analysis

Biomonitoring of toxic metals, organochlorine pesticides, and polybrominated biphenyl 153 in Michigan urban anglers

The 32-mile Detroit River and surrounding tributaries have been designated as a Great Lakes Area of Concern due to pollution from decades of municipal and industrial discharges, sewer overflows and urban development. The Agency for Toxic Substances and Disease Registry and the Michigan Department of Health and Human Services conducted a biomonitoring study to assess exposures to persistent toxic substances in Detroit urban shoreline anglers who may be at high exposure risk due to consumption of locally caught fish. Using a modified venue-based sampling approach, 287 adult shoreline anglers along the Detroit River were recruited and participated in the program. Study participants provided blood and urine specimens and completed a questionnaire interview. In this report, we examine percentile estimates for blood lead, blood manganese, urine arsenic, urine mercury, urine cadmium, organochlorine pesticides in serum (mirex, hexachlorobenzene, chlordane), and serum polybrominated biphenyl 153 (PBB 153) concentrations among study participants. Multiple linear regression was used to identify predictors of contaminant concentrations. The Detroit urban anglers' blood lead concentrations were 2 times higher than the general adult U.S. population (median (95% CI): 2.9 μg/dL (1.8–2.3) vs. 0.94 μg/dL (0.90–0.98)). PBB 153 levels were 1.8 times higher than the general adult U.S. population at the 95th percentile (95th percentile, 95% CI: 62.7 ng/g of lipid, 53.2–75.2 vs. 34.6 ng/g of lipid, 12.8–66.8). Percentile estimates of the other study pollutants were similar to background levels found in the general U.S. population. Eating more locally caught fish was not associated with increased body burdens for any of the contaminants examined in this report. Higher blood lead was associated with increased age, male sex, current smoking, residing in a home built before 1960, an annual income less than $25,000, and a work history of lead paint removal. Evidence of PBB exposure in our study cohort likely reflects the continued effect of a widespread contamination of livestock feed in 1973 among Michigan's lower peninsula population. These study results help determine if the pollutants examined warrant further consideration in subsequent population-based biomonitoring of frequent consumers of fish from the Detroit River and surrounding waterways. The biomonitoring data from this study also served to inform public health officials regarding the potential need for environmental public health actions to reduce harmful exposures.