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Chemical Research in Toxicology Sep 2021Exposure to polychlorinated biphenyls (PCBs) is implicated in adverse neurotoxic outcomes. However, the impact of PCBs on the adolescent nervous system has received... (Review)
Review
Exposure to polychlorinated biphenyls (PCBs) is implicated in adverse neurotoxic outcomes. However, the impact of PCBs on the adolescent nervous system has received inadequate attention. We conducted a comprehensive review to identify studies of neurotoxic outcomes following PCB exposure during the adolescent period in rodents. Only four papers were found to meet all inclusion criteria. PCB exposure in adolescent rats caused disruptions in the main functions of the prefrontal cortex, resulting in cognitive deficits. This comprehensive review demonstrates that more research is needed to characterize how PCB exposure adversely affects the adolescent nervous system.
Topics: Adolescent; Animals; Humans; Nervous System; Polychlorinated Biphenyls
PubMed: 34491731
DOI: 10.1021/acs.chemrestox.1c00226 -
Cells Jul 2022It is increasingly recognized that hypoxia may develop in adipose tissue as its mass expands. Adipose tissue is also the main reservoir of lipophilic pollutants,...
It is increasingly recognized that hypoxia may develop in adipose tissue as its mass expands. Adipose tissue is also the main reservoir of lipophilic pollutants, including polychlorinated biphenyls (PCBs). Both hypoxia and PCBs have been shown to alter adipose tissue functions. The signaling pathways induced by hypoxia and pollutants may crosstalk, as they share a common transcription factor: aryl hydrocarbon receptor nuclear translocator (ARNT). Whether hypoxia and PCBs crosstalk and affect adipokine secretion in human adipocytes remains to be explored. Using primary human adipocytes acutely co-exposed to different levels of hypoxia (24 h) and PCB126 (48 h), we observed that hypoxia significantly inhibits the PCB126 induction of cytochrome P450 (CYP1A1) transcription in a dose-response manner, and that Acriflavine (ACF)-an HIF1α inhibitor-partially restores the PCB126 induction of CYP1A1 under hypoxia. On the other hand, exposure to PCB126 did not affect the transcription of the vascular endothelial growth factor-A (VEGFA) under hypoxia. Exposure to hypoxia increased leptin and interleukin-6 (IL-6), and decreased adiponectin levels dose-dependently, while PCB126 increased IL-6 and IL-8 secretion in a dose-dependent manner. Co-exposure to PCB126 and hypoxia did not alter the adipokine secretion pattern observed under hypoxia and PCB126 exposure alone. In conclusion, our results indicate that (1) hypoxia inhibits PCB126-induced CYP1A1 expression at least partly through ARNT-dependent means, suggesting that hypoxia could affect PCB metabolism and toxicity in adipose tissue, and (2) hypoxia and PCB126 affect leptin, adiponectin, IL-6 and IL-8 secretion differently, with no apparent crosstalk between the two factors.
Topics: Adipocytes; Adipokines; Adiponectin; Aryl Hydrocarbon Receptor Nuclear Translocator; Cytochrome P-450 CYP1A1; Environmental Pollutants; Humans; Hypoxia; Interleukin-6; Interleukin-8; Leptin; Polychlorinated Biphenyls; Vascular Endothelial Growth Factor A
PubMed: 35892579
DOI: 10.3390/cells11152282 -
Journal of Internal Medicine Feb 2020Co-exposure to environmental contaminants present in fish could mitigate the beneficial effects of fish consumption and possibly explain the lack of association observed...
Cardiovascular and cancer mortality in relation to dietary polychlorinated biphenyls and marine polyunsaturated fatty acids: a nutritional-toxicological aspect of fish consumption.
BACKGROUND
Co-exposure to environmental contaminants present in fish could mitigate the beneficial effects of fish consumption and possibly explain the lack of association observed for mortality in some geographical regions.
OBJECTIVE
To assess the independent associations of dietary exposure to polychlorinated biphenyls (PCBs) and long-chain omega-3 fish fatty acids intake with cardiovascular and cancer mortality.
METHODS
We used the prospective population-based Swedish Mammography Cohort and the Cohort of Swedish Men comprising 32 952 women and 36 545 men, free from cancer, cardiovascular disease and diabetes at baseline in 1998. Validated estimates of dietary PCBs and long-chain omega-3 fish fatty acids [i.e. eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)] intake were obtained via a food frequency questionnaire at baseline. Information on death was ascertained through register linkage.
RESULTS
During a mean follow-up of 15.5 years, we ascertained 16 776 deaths. We observed for cardiovascular mortality, comparing extreme quintiles in multivariable models mutually adjusted for PCBs and EPA-DHA, dose-dependent associations for dietary PCB exposure, hazard ratio (HR) 1.31 (CI 95%: 1.08 to 1.57; P-trend 0.005) and for dietary EPA-DHA intake, HR 0.79 (CI 95%: 0.66 to 0.95; P-trend 0.041). For cancer mortality, no clear associations were discerned.
CONCLUSION
The beneficial effect of fish consumption on the cardiovascular system seems compromised by co-exposure to PCBs - one likely explanation for the inconsistent associations observed between fish consumption and mortality.
Topics: Animals; Cardiovascular Diseases; Diet; Fatty Acids, Unsaturated; Female; Fishes; Humans; Male; Middle Aged; Neoplasms; Polychlorinated Biphenyls; Prospective Studies; Sweden
PubMed: 31628875
DOI: 10.1111/joim.12995 -
Environment International May 2015Whereas it is well established that prenatal exposure to polychlorinated biphenyls (PCBs) can disrupt children's behavior, early postnatal exposure has received...
BACKGROUND
Whereas it is well established that prenatal exposure to polychlorinated biphenyls (PCBs) can disrupt children's behavior, early postnatal exposure has received relatively little attention in environmental epidemiology.
OBJECTIVES
To evaluate prenatal and postnatal exposures to PCB-153, a proxy of total PCB exposure, and their relation to inattention and activity in 5-year-old Inuits from the Cord Blood Monitoring Program.
METHODS
Prenatal exposure to PCBs was informed by cord plasma PCB-153 levels. We used a validated pharmacokinetic model to estimate monthly infants' levels across the first year of life. Inattention and activity were assessed by coding of video recordings of children undergoing fine motor testing. We used multivariable linear regression to evaluate the association between prenatal and postnatal PCB-153 levels and inattention (n=97) and activity (n=98) at 5years of age.
RESULTS
Cord plasma PCB-153 was not associated with inattention and activity. Each interquartile range (IQR) increase in estimated infant PCB-153 levels at 2months was associated with a 1.02% increase in the duration of inattention (95% CI: 0.04, 2.00). Statistical adjustment for the duration of breastfeeding slightly increased regression coefficients for postnatal level estimates, some of which became statistically significant for inattention (months: 2-4) and activity (months: 2-5).
CONCLUSIONS
Our study adds to the growing evidence of postnatal windows of development during which children are more susceptible to neurotoxicants like PCBs.
Topics: Attention; Attention Deficit Disorder with Hyperactivity; Child, Preschool; Environmental Exposure; Environmental Pollutants; Female; Fetal Blood; Humans; Infant; Inuit; Male; Models, Theoretical; Neurotoxins; Polychlorinated Biphenyls; Pregnancy; Prenatal Exposure Delayed Effects; Regression Analysis
PubMed: 25796081
DOI: 10.1016/j.envint.2015.02.004 -
Regulatory Toxicology and Pharmacology... Mar 2021Non-dioxin like polychlorinated biphenyls (NDL PCB) are recognized neurotoxicants with implications on altered neurodevelopment and neurodegeneration in exposed...
Non-dioxin like polychlorinated biphenyls (NDL PCB) are recognized neurotoxicants with implications on altered neurodevelopment and neurodegeneration in exposed organisms. NDL PCB neurotoxic relative potency schemes have been developed for a single mechanism, namely activity toward the ryanodine receptor (RyR), or combined mechanisms including, but not limited to, alterations of RyR and dopaminergic pathways. We compared the applicability of the two neurotoxic equivalency (NEQ) schemes and applied each scheme to PCB mixtures found in environmental and human serum samples. A multiple mechanistic NEQ predicts higher neurotoxic exposure concentrations as compared to a scheme based on the RyR alone. Predictions based on PCB ortho categorization, versus homologue categorization, lead to a higher prediction of neurotoxic exposure concentrations, especially for the mMOA. The application of the NEQ schemes to PCB concentration data suggests that PCBs found in fish from US lakes represent a considerable NEQ exposure to fish consuming individuals, that indoor air of schools contained high NEQ concentrations representing an exposure concern when inhaled by children, and that levels already detected in the serum of adults and children may contribute to neurotoxicity. With further validation and in vivo exposure data the NEQ scheme would help provide a more inclusive measure of risk presented by PCB mixtures.
Topics: Animals; Dioxins; Environmental Monitoring; Fishes; Humans; Neurotoxicity Syndromes; Polychlorinated Biphenyls; United States; United States Environmental Protection Agency; Water Pollutants, Chemical
PubMed: 33346014
DOI: 10.1016/j.yrtph.2020.104842 -
Scientific Reports Feb 2016Aerobic mineralization of PCBs, which are toxic and persistent organic pollutants, involves the upper (biphenyl, BP) and lower (benzoate, BZ) degradation pathways. The...
Aerobic mineralization of PCBs, which are toxic and persistent organic pollutants, involves the upper (biphenyl, BP) and lower (benzoate, BZ) degradation pathways. The activity of different members of the soil microbial community in performing one or both pathways, and their synergistic interactions during PCB biodegradation, are not well understood. This study investigates BP and BZ biodegradation and subsequent carbon flow through the microbial community in PCB-contaminated soil. DNA stable isotope probing (SIP) was used to identify the bacterial guilds involved in utilizing (13)C-biphenyl (unchlorinated analogue of PCBs) and/or (13)C-benzoate (product/intermediate of BP degradation and analogue of chlorobenzoates). By performing SIP with two substrates in parallel, we reveal microbes performing the upper (BP) and/or lower (BZ) degradation pathways, and heterotrophic bacteria involved indirectly in processing carbon derived from these substrates (i.e. through crossfeeding). Substrate mineralization rates and shifts in relative abundance of labeled taxa suggest that BP and BZ biotransformations were performed by microorganisms with different growth strategies: BZ-associated bacteria were fast growing, potentially copiotrophic organisms, while microbes that transform BP were oligotrophic, slower growing, organisms. Our findings provide novel insight into the functional interactions of soil bacteria active in processing biphenyl and related aromatic compounds in soil, revealing how carbon flows through a bacterial community.
Topics: Bacteria; Benzoates; Biodegradation, Environmental; Biphenyl Compounds; Environmental Pollution; Hazardous Waste; Hydrocarbons, Aromatic; Polychlorinated Biphenyls; RNA, Ribosomal, 16S; Soil; Soil Microbiology; Soil Pollutants
PubMed: 26915282
DOI: 10.1038/srep22145 -
The Science of the Total Environment Feb 2023Most fish consumption advisories in the United States (U.S.) are issued for mercury and polychlorinated biphenyls (PCBs), and recently per- and polyfluoroalkyl...
Most fish consumption advisories in the United States (U.S.) are issued for mercury and polychlorinated biphenyls (PCBs), and recently per- and polyfluoroalkyl substances (PFAS) have become a contaminant group that warrants fish consumption advice. An unequal probability survey design was developed to allow a comprehensive characterization of mercury, PCB, and PFAS contamination in fish from U.S. rivers on a national scale. During 2013-14 and 2018-19, fish fillet samples were collected from 353 and 290 river sites, respectively, selected randomly from the target population of rivers (≥5th order in size) in the conterminous U.S. These comprised nationally representative samples, with results extrapolated to chemical-specific sampled populations of 48,826-79,448 river kilometers (km) in 2013-14 and 66,142 river km in 2018-19. National distribution estimates were developed for total mercury, all 209 PCB congeners, and up to 33 PFAS (including perfluorooctane sulfonate or PFOS) in river fish. All fillet tissue samples contained detectable levels of mercury and PCBs. One or more PFAS were detected in 99.7 % and 95.2 % of the fillet samples from fish collected in 2013-14 and 2018-19, respectively. Fish tissue screening levels applied to national contaminant probability distributions allowed an estimation of the percentage of the sampled population of river lengths that contained fish with fillet concentrations above a level protective of human health. Fish tissue screening level exceedances for an average level of fish consumption ranged from 23.5 % to 26.0 % for mercury, 17.3 % to 51.6 % for PCBs, and 0.7 % to 9.1 % for PFOS.
Topics: Animals; Fishes; Fluorocarbons; Mercury; Polychlorinated Biphenyls; United States; Water Pollutants, Chemical
PubMed: 36574550
DOI: 10.1016/j.scitotenv.2022.160557 -
Ecotoxicology and Environmental Safety Mar 2024Whether and to what extent the impact of exposure to various polychlorinated biphenyls (PCBs) congeners on diabetes, as well as the important contributors, have remained...
BACKGROUND
Whether and to what extent the impact of exposure to various polychlorinated biphenyls (PCBs) congeners on diabetes, as well as the important contributors, have remained unclear.
OBJECTIVE
We aimed to investigate the association patterns between PCBs mixture and diabetes, identify the critical congeners, and explore the potential modifiers.
METHODS
The present study included 5900 U.S. adults from the National Health and Nutrition Examination Survey (NHANES) conducted between 2007 and 2016. Weighted logistic regression, restricted cubic spline regression, weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR) were applied to estimate the linear and non-linear associations of single and mixed PCB exposure with diabetes. Subgroup analyses were also conducted to explore potential sex differences.
RESULTS
In the weighted logistic regression model, total PCBs were positively associated with diabetes (OR = 1.33, P < 0.025), and significant non-linear associations were observed using RCS analyses. The non-linear positive association between PCBs mixed exposure and diabetes was likewise found in the WQS and BKMR results. PCB180, PCB194, PCB196, and PCB167 were with the highest weights in the WQS, and PCB209 and PCB66 were with the highest posterior inclusion probabilities in the BKMR. Additionally, exposure to total PCBs and most of individual PCB congeners were significantly associated with elevated risk of in females (OR = 1.74; P for trend < 0.001), while fewer significant associations were observed in males.
CONCLUSION
The present study highlighted the importance of the long-term surveillance of PCBs and the need to enhance protective measures against them. Notably, these associations were non-linear, congener-specific, and significantly stronger in females than males, especially at relatively high levels of PCBs exposure. Further prospective and mechanistic studies were warranted to ascertain the causal effects between PCBs mixture and diabetes.
Topics: Adult; Female; Humans; Male; Polychlorinated Biphenyls; Environmental Pollutants; Environmental Exposure; Nutrition Surveys; Bayes Theorem; Diabetes Mellitus
PubMed: 38340600
DOI: 10.1016/j.ecoenv.2024.116091 -
Reviews on Environmental Health Mar 2022Persistent Organic Pollutants (POPs) are exogenous, artificially made chemicals that can disrupt the biological system of individuals and animals. POPs encompass a... (Review)
Review
Persistent Organic Pollutants (POPs) are exogenous, artificially made chemicals that can disrupt the biological system of individuals and animals. POPs encompass a variety of chemicals including, dioxins, organochlorines (OCs), polychlorinated biphenyl (PCBs), and perfluoroalkyl substances (PFASs) that contain a long half-life and highly resistant to biodegradation. These environmental pollutants accumulate over time in adipose tissues of living organisms and alter various insulin function-related genes. Childhood Metabolic Syndrome (MetS) consists of multiple cardiovascular risk factors, insulin function being one of them. Over the years, the incidence of the syndrome has increased dramatically. It is imperative to explore the role of persistent organic pollutants in the development of Childhood Metabolic Syndrome. Some epidemiological studies have reported an association between prenatal exposure to POPs and offspring MetS development throughout childhood. These findings have been replicated in animal studies in which these pollutants exercise negative health outcomes such as obesity and increased waist circumference. This review discusses the role of prenatal exposure to POPs among offspring who develop MetS in childhood, the latest research on the MetS concept, epidemiological and experimental findings on MetS, and the POPs modes of action. This literature review identified consistent research results on this topic. Even though the studies in this review had many strengths, one major weakness was the usage of different combinations of MetS criteria to measure the outcomes. These findings elucidate the urgent need to solidify the pediatric MetS definition. An accurate definition will permit scientists to measure the MetS as a health outcome properly and allow clinicians to diagnose pediatric MetS and provide individualized treatment appropriately.
Topics: Animals; Environmental Pollutants; Female; Humans; Metabolic Syndrome; Persistent Organic Pollutants; Polychlorinated Biphenyls; Pregnancy; Prenatal Exposure Delayed Effects; Risk Factors
PubMed: 33866704
DOI: 10.1515/reveh-2020-0113 -
Environment International Jun 2020Polychlorinated biphenyls (PCBs) and their biotransformation products, hydroxylated (OH-PCBs) and methoxylated derivatives (MeO-PCBs), have been detected in the...
Polychlorinated biphenyls (PCBs) and their biotransformation products, hydroxylated (OH-PCBs) and methoxylated derivatives (MeO-PCBs), have been detected in the environment and biota, especially crops. However, to date, little information is available on the phytotoxicity and metabolic responses induced by these chemicals in crops. In this study, we exposed rice (Oryza sative L.) seedlings to 2,3,4,5-tetrachlorobiphenyl (CB-61) and its hydroxylated (4'-OH-CB-61) and methoxylated derivatives (4'-MeO-CB-61) at 0, 10, 50, 100 and 500 μg/L, respectively. After exposure for 14 days, significantly growth inhibition and oxidative damage were observed, among which the toxicities of 4'-OH-CB-61 and 4'-MeO-CB-61 were greater than that of the parent PCBs. Metabolomics analysis indicated that exposure to the three chemicals induced different metabolic responses. 4'-MeO-CB-61 mainly affected the saccharide catabolism, including pyruvate metabolism, the TCA cycle, the transfer of acetyl groups into mitochondria and the Warburg effect, resulting in a greater energy consumption. Moreover, both CB-61 and 4'-OH-CB-61 promoted several amino acid metabolism and fatty acid biosynthesis, thereby alleviating the potential ROS damage. This study for the first time evaluates and reveals the phytotoxicity of OH-PCBs and MeO-PCBs at the metabolic level, which attempts to provide important information for accurately evaluating the environmental risks of PCBs from the perspective of metabolism.
Topics: Biotransformation; Hydroxylation; Oryza; Polychlorinated Biphenyls
PubMed: 32272295
DOI: 10.1016/j.envint.2020.105695