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Metabolites Aug 2022As a high trophic-level species, ringed seals () and beluga whales () are particularly vulnerable to elevated concentrations of biomagnifying contaminants, such as...
As a high trophic-level species, ringed seals () and beluga whales () are particularly vulnerable to elevated concentrations of biomagnifying contaminants, such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and mercury (Hg). These species also face climate-change-related impacts which are leading to alterations in their diet and associated contaminant exposure. The metabolomic profile of marine mammal tissues and how it changes to environmental stressors is poorly understood. This study characterizes the profiles of 235 metabolites across plasma, liver, and inner and outer blubber in adult ringed seals and beluga whales and assesses how these profiles change as a consequence of contaminants and dietary changes. In both species, inner and outer blubber were characterized by a greater proportion of lipid classes, whereas the dominant metabolites in liver and plasma were amino acids, carbohydrates, biogenic amines and lysophosphatidylcholines. Several metabolite profiles in ringed seal plasma correlated with δC, while metabolite profiles in blubber were affected by hexabromobenzene in ringed seals and PBDEs and Hg in belugas. This study provides insight into inter-matrix similarities and differences across tissues and suggests that plasma and liver are more suitable for studying changes in diet, whereas liver and blubber are more suitable for studying the impacts of contaminants.
PubMed: 36144217
DOI: 10.3390/metabo12090813 -
Ecotoxicology and Environmental Safety Oct 2022Bisphenols, including Bisphenol A (BPA), Tetrabromobisphenol A (TBBPA), and Tetrabromobisphenol S (TBBPS), have been widely applied in the production of polycarbonate...
Bisphenols, including Bisphenol A (BPA), Tetrabromobisphenol A (TBBPA), and Tetrabromobisphenol S (TBBPS), have been widely applied in the production of polycarbonate plastics and epoxy resins and have been detected in the environment worldwide. The frequent detection of bisphenols in maternal and fetal samples has raised concerns about their toxic effects on human embryonic development, especially on the development of the central nervous system. However, the effect of bisphenols on human retinal development is still unknown. In this study, to evaluate the toxicity of bisphenols on early retinal development, human embryonic stem cells were induced to differentiate into retinal organoids that responded to BPA, TBBPA, and TBBPS, at human exposure relevant concentrations. The global gene expression of retinal organoids was analyzed by RNA sequencing (RNA-seq). A set of retinal development-related biological processes, including neuron differentiation, phototransduction, axon guidance, and retina layer formation, were identified in retinal organoids corresponding to different developmental stages. The RNA-seq data also showed that BPA, TBBPA, and TBBPS influenced retinal development by interfering with the Cytokine-cytokine receptor interaction pathway. HSPA6, HIF1A-AS3, CDC20B, IL19, OAS1, HSPA7, and RN7SK were dysregulated by these chemicals. Additionally, BPA, TBBPA, and TBBPS exhibited different toxic effects on neural retina development, with TBBPA appearing to exert more toxicity than BPA and TBBPS. Furthermore, three bisphenols exhibited different effects at different stages of neural retina development. The sensitivity of retinal development to bisphenols depends on their developmental stage. This study provides new insights into the deep dissection of retinotoxicity after prenatal bisphenol exposure.
Topics: Benzhydryl Compounds; Cytokines; Epoxy Resins; Female; HSP70 Heat-Shock Proteins; Humans; Organoids; Phenols; Polybrominated Biphenyls; Pregnancy; Receptors, Cytokine; Retina
PubMed: 36126549
DOI: 10.1016/j.ecoenv.2022.114094 -
Neuroendocrinology 2023Flame retardants (FRs) are common bodily and environmental pollutants, creating concern about their potential toxicity. We and others have found that the commercial...
INTRODUCTION
Flame retardants (FRs) are common bodily and environmental pollutants, creating concern about their potential toxicity. We and others have found that the commercial mixture FireMaster® 550 (FM 550) or its individual brominated (BFR) and organophosphate ester (OPFR) components are potential developmental neurotoxicants. Using Wistar rats, we previously reported that developmental exposure to FM 550 or its component classes produced sex- and compound-specific effects on adult socioemotional behaviors. The underlying mechanisms driving the behavioral phenotypes are unknown.
METHODS
To further mechanistic understanding, here we conducted transcriptomics in parallel with a novel lipidomics approach using cortical tissues from newborn siblings of the rats in the published behavioral study. Inclusion of lipid composition is significant because it is rarely examined in developmental neurotoxicity studies. Pups were gestationally exposed via oral dosing to the dam to FM 550 or the BFR or OPFR components at environmentally relevant doses.
RESULTS
The neonatal cortex was highly sexually dimorphic in lipid and transcriptome composition, and males were more significantly impacted by FR exposure. Multiple adverse modes of action for the BFRs and OPFRs on neurodevelopment were identified, with the OPFRs being more disruptive than the BFRs via multiple mechanisms including dysregulation of mitochondrial function and disruption of cholinergic and glutamatergic systems. Disrupted mitochondrial function by environmental factors has been linked to a higher risk of autism spectrum disorders and neurodegenerative disorders. Impacted lipid classes included ceramides, sphingomyelins, and triacylglycerides. Robust ceramide upregulation in the OPFR females could suggest a heightened risk of brain metabolic disease.
CONCLUSIONS
This study reveals multiple mechanisms by which the components of a common FR mixture are developmentally neurotoxic and that the OPFRs may be the compounds of greatest concern.
Topics: Male; Female; Rats; Animals; Rats, Wistar; Organophosphates; Polybrominated Biphenyls; Flame Retardants; Lipids
PubMed: 36075192
DOI: 10.1159/000526959 -
Environmental Research Nov 2022In 1973-74, a polybrominated biphenyl (PBB) flame retardant mixture was shipped to Michigan livestock feed mills in place of a nutritional supplement and contaminated...
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.
Topics: Birth Weight; Child; Environmental Pollutants; Fathers; Female; Humans; Infant; Infant, Newborn; Male; Polybrominated Biphenyls; Polychlorinated Biphenyls; Premature Birth; Semen
PubMed: 36041536
DOI: 10.1016/j.envres.2022.114215 -
Environmental Science and Pollution... Jan 2023Tetrabromobisphenol A (TBBPA) is adsorbed on sediments in river environments, and various environmental factors have distinct effects on its adsorption behaviour....
Tetrabromobisphenol A (TBBPA) is adsorbed on sediments in river environments, and various environmental factors have distinct effects on its adsorption behaviour. Investigating the adsorption behaviour of TBBPA on the sediments in Weihe River Basin is critical for protecting the water environment and providing a theoretical basis for the prevention and control of brominated flame retardant pollution. In this study, the adsorption behaviour of TBBPA on Weihe River sediment was investigated by conducting batch equilibrium experiments, and the effects of pH, dissolved organic matter, and ionic strength on the adsorption of TBBPA were discussed. The obtained results revealed that rapid adsorption was the main mechanism of the TBBPA kinetic adsorption process. The isothermal adsorption behaviour of TBBPA was well fitted by Freundlich model (R 99.21%) than Langmuir model (R 98.59%). The adsorption capacity for TBBPA is 34.13 mg/kg. The thermodynamic results revealed that the adsorption process of TBBPA by the sediment was a spontaneous endothermic reaction. The increase in pH and ionic strength inhibited the adsorption of sediments on TBBPA. With the increase in the humic acid concentration, the adsorption of TBBPA initially increased and subsequently decreased. Synchrotron radiation-Fourier transform infrared spectroscopy indicated that the adsorption mechanism of TBBPA on the surface of sediment was mainly π-π and hydrogen bonds. The obtained results are useful for understanding of TBBPA migration and transformation in river water bodies.
Topics: Rivers; Adsorption; Water Pollutants, Chemical; Polybrominated Biphenyls; China; Water
PubMed: 36001257
DOI: 10.1007/s11356-022-22259-7 -
Environmental Monitoring and Assessment Aug 2022River otters (Lontra canadensis) are apex predators that bioaccumulate contaminants via their diet, potentially serving as biomonitors of watershed health. They reside...
River otters (Lontra canadensis) are apex predators that bioaccumulate contaminants via their diet, potentially serving as biomonitors of watershed health. They reside throughout the Green-Duwamish River, WA (USA), a watershed encompassing an extreme urbanization gradient, including a US Superfund site slated for a 17-year remediation. The objectives of this study were to document baseline contaminant levels in river otters, assess otters' utility as top trophic-level biomonitors of contaminant exposure, and evaluate the potential for health impacts on this species. We measured a suite of contaminants of concern, lipid content, nitrogen stable isotopes (δN), and microsatellite DNA markers in 69 otter scat samples collected from twelve sites. Landcover characteristics were used to group sampling sites into industrial (Superfund site), suburban, and rural development zones. Concentrations of polychlorinated biphenyls (PCBs), polybrominated diphenyl ether flame-retardants (PBDEs), dichlorodiphenyl-trichloroethane and its metabolites (DDTs), and polycyclic aromatic hydrocarbons (PAHs) increased significantly with increasing urbanization, and were best predicted by models that included development zone, suggesting that river otters are effective biomonitors, as defined in this study. Diet also played an important role, with lipid content, δN or both included in all best models. We recommend river otter scat be included in evaluating restoration efforts in this Superfund site, and as a potentially useful monitoring tool wherever otters are found. We also report ΣPCB and ΣPAH exposures among the highest published for wild river otters, with almost 70% of samples in the Superfund site exceeding established levels of concern.
Topics: Animals; Environmental Monitoring; Environmental Pollutants; Halogenated Diphenyl Ethers; Lipids; Otters; Water Pollutants, Chemical
PubMed: 35970905
DOI: 10.1007/s10661-022-10272-9 -
Microorganisms Jul 2022Decabromodiphenyl ether (BDE-209), a polybrominated diphenyl ether (PBDE) homolog, seriously threatens human health. In this study, a strain with high BDE-209...
Decabromodiphenyl ether (BDE-209), a polybrominated diphenyl ether (PBDE) homolog, seriously threatens human health. In this study, a strain with high BDE-209 degradation activity, named TAW-CT127, was isolated from Tong'an Bay, Xiamen. Under laboratory conditions, the strain's optimal growth temperature, pH, and salinity are 45 °C, 7.0, and 0-2.5%, respectively. Scanning electron microscopy (SEM) analysis shows that TAW-CT127 is damaged when grown in manual marine culture (MMC) medium with BDE-209 as the sole carbon source instead of eutrophic conditions. In the dark, under the conditions of 28 °C, 160 rpm, and 3 g/L (wet weight) TAW-CT127, the degradation rate of 50 mg/L BDE-209 is 81.07%. The intermediate metabolites are hexabromo-, octabromo-, and nonabromo-diphenyl ethers. Through whole-genome sequencing, multiple dehalogenases were found in the genome of TAW-CT127; these may be involved in the production of lower-brominated diphenyl ethers. Additionally, biphenyl-2,3-dioxygenase (BDO) in TAW-CT127 may catalyze the debromination reaction of BDE-209. Our research provides a new high-efficiency strain for bioremediation of BDE-209 pollution, and lays the foundation for the preliminary exploration of genes associated with BDE-209 degradation.
PubMed: 35889160
DOI: 10.3390/microorganisms10071441 -
Environmental Pollution (Barking, Essex... Oct 2022Tetrabromobisphenol A (TBBPA) is the most used flame retardant worldwide and has become a threat to aquatic ecosystems. Previous research into the degradation of this...
Tetrabromobisphenol A (TBBPA) is the most used flame retardant worldwide and has become a threat to aquatic ecosystems. Previous research into the degradation of this micropollutant in anaerobic bioreactors has suggested several identities of putative TBBPA degraders. However, the organisms actively degrading TBBPA under in situ conditions have so far not been identified. Protein-stable isotope probing (protein-SIP) has become a cutting-edge technique in microbial ecology for enabling the link between identity and function under in situ conditions. Therefore, it was hypothesized that combining protein-based stable isotope probing with metagenomics could be used to identify and provide genomic insight into the TBBPA-degrading organisms. The identified C-labelled peptides were found to belong to organisms affiliated to Phytobacter, Clostridium, Sporolactobacillus, and Klebsilla genera. The functional classification of identified labelled peptides revealed that TBBPA is not only transformed by cometabolic reactions, but also assimilated into the biomass. By application of the proteogenomics with labelled micropollutants (protein-SIP) and metagenome-assembled genomes, it was possible to extend the current perspective of the diversity of TBBPA degraders in wastewater and predict putative TBBPA degradation pathways. The study provides a link to the active TBBPA degraders and which organisms to favor for optimized biodegradation.
Topics: Anaerobiosis; Biodegradation, Environmental; Bioreactors; Ecosystem; Isotopes; Polybrominated Biphenyls; Proteogenomics
PubMed: 35872283
DOI: 10.1016/j.envpol.2022.119786 -
Environmental Pollution (Barking, Essex... Sep 2022Contracting Parties to the OSPAR Convention for the Protection of the Maine Environment of the North-East Atlantic are required to undertake monitoring and assessment of...
Contracting Parties to the OSPAR Convention for the Protection of the Maine Environment of the North-East Atlantic are required to undertake monitoring and assessment of both inorganic and organic contaminants. There is a requirement to assess contaminants across different trophic levels on an ecosystem-specific basis. However, this is currently constrained by the availability of relevant samples to cover the full range of trophic levels. This study investigates the variability (inter- and intra-species variation) of the concentrations and distributions of thirty-two polychlorinated biphenyl (PCB) congeners and nine polybrominated diphenyl ether (PBDE) congeners in twenty-six species covering four trophic levels from different geographic locations around Scotland. Trophic magnification factors (TMFs) were calculated using a traditional method and a balanced method for both the ICES-7 PCBs and BDE47, to refine and improve the application of TMFs to assess and predict biomagnification risk to biota in the marine environment. There were clear differences in congener percentage distribution between sample categories and species, with differences influenced by physiological processes and eco-biological parameters. Trophic magnification was found to occur for the ICES-7 PCBs and BDE47 using the traditional method, with the highest degree of trophic magnification reported for CB52. An unbalanced dataset was found to influence the calculated TMF and in some cases, the overall conclusion of the trophic transfer of PCB and PBDE congeners. The balanced method is highly recommended for calculating TMFs to ensure that the TMF is a true indication of the biomagnification potential, particularly when conducting regional comparisons for which sampling requirements are difficult to achieve.
Topics: Animals; Bioaccumulation; Ecosystem; Environmental Monitoring; Fishes; Food Chain; Halogenated Diphenyl Ethers; Polychlorinated Biphenyls; Water Pollutants, Chemical
PubMed: 35841989
DOI: 10.1016/j.envpol.2022.119752 -
Environment International Aug 2022After the PBBs pollution incident in Michigan, a large number of studies focused on the exposure of people to 2,2',4,4',5,5'-hexabromobiphenyl (BB-153), but paid less...
After the PBBs pollution incident in Michigan, a large number of studies focused on the exposure of people to 2,2',4,4',5,5'-hexabromobiphenyl (BB-153), but paid less attention to other PBBs congeners in human serum. In this study, three monobromobiphenyls (BB-1, BB-2 and BB-3), five dibromobiphenyls (BB-4, BB-7, BB-9, BB-10 and BB-15), decabromobiphenyl (BB-209) and BB-153 in the serum of the general population in Wuxi from 2012 to 2016 were detected by GC-MS/MS. The most abundant congeners in serum samples were BB-1(median 254 ng·g lw), BB-10 (median 141 ng·g lw) and BB-209 (median 68.4 ng·g lw). The detection rate of BB-153 is less than 10%, and the concentration is far lower than that in other areas. The concentrations of BB-1, BB-10 and BB-209 are 3-4 orders of magnitude higher than the maximum concentration of BB-153. Serum concentrations of BB-209 increased significantly from 2012 to 2016 (p = 0.025). In addition, the concentrations of BB-1 in serum of females were significantly higher than that of males, and the concentrations of BB-1, BB-10 and BB-209 in serum of young adults were significantly higher than that of middle-aged adults. Finally, we found that BB-1 and BB-10 may have similar disruption on the binding of T3 and TRβ as BB-153, while BB-209 has little effect on the binding of T3 and TRβ. This suggests that we should pay more attention to the damage of BB-1 and BB-10 to thyroid in the future.
Topics: Male; Female; Middle Aged; Young Adult; Humans; Thyroid Hormone Receptors beta; Tandem Mass Spectrometry; Polybrominated Biphenyls; Thyroid Gland
PubMed: 35810546
DOI: 10.1016/j.envint.2022.107390