Polybrominated Diphenyl Ethers Research Articles

Dermal exposure assessment of formal e-waste dismantlers to flame retardants and plasticizers using passive sampling methodologies

The recycling of e-waste can lead to the release of organic chemicals when materials containing additives are subjected to dismantling and grinding. In this context, the exposure of workers from a Catalonian e-waste facility to flame retardants and plasticizers (including organophosphate esters (OPEs), polybrominated diphenyl ethers (PBDEs), novel brominated flame retardants (NBFRs) and dechloranes) was assessed using T-shirts and wristbands as passive samplers. The study area includes an area exclusively dedicated to cathodic ray-tube (CRT) TVs dismantling, and a grinding area where the rest of e-waste is ground. All the families of compounds were detected in both T-shirts and wristbands, with the highest concentration levels corresponding to OPEs, followed by PBDEs, NBFRs, and dechloranes. The CRT area presented higher concentration levels than the grinding area. The compounds with higher concentrations in T-shirts were 2-ethylhexyl diphenyl phosphate (EHDPP), diphenyl cresyl phosphate (DCP) and triphenyl phosphate (TPHP), and the total concentration of all groups ranged between 293 and 8324 ng/dm2-h (hour). In the case of the wristbands, the most abundant compounds were DCP, TPHP, and BDE-209, with total concentrations between 188 and 2248 ng/dm2-h. The two sampling methods appear to be complementary, as T-shirts collect coarser particles, while wristbands also capture volatile compounds. Based on normalized surface and time concentrations, the estimated daily intake (EDI) through dermal contact was calculated and carcinogenic and non-carcinogenic risks (CR and non-CR) associated with this activity assessed. The results show median CR 29 and 16 times below the threshold in CRT and grinding areas respectively. The non-CR medians were 2 and 3 times below the threshold, although in the CRT area one exceptional value surpassed the threshold, suggesting that risk can exist for some workers in the facility.

Distribution and co-occurrence of microplastics and co-existing pollutants in bottom water and sediment of the East China Sea

Microplastics (MPs) contamination in marine environment has been an emerging issue worldwide, notably due to the potential ecological risks of MPs with co-existing environmental contaminants and released toxic plastic additives. To verify the co-occurrence characteristics of MPs and co-existing pollutants in the benthic boundary layer (BBL), the distribution characteristics of MPs, and selected heavy metals (HMs) and halogenated flame retardants (Polybrominated diphenyl ethers, PBDEs, and Dechlorane Plus) in the bottom water and sediment were comprehensively investigated in the East China Sea (ECS). The sampling sites were selected along the coast of ECS, where might be significantly affected by terrigenous inputs and anthropogenic sources. MPs were abundant in the bottom water (62.8–480.2 items/L) and sediment (80.1–1346.7 items/kg d.w.) with polyester, polyethylene, and polypropylene being as the most abundant types and characterized as fiber/line, particle size 200–500 μm, and transparent/white. The abundance and characteristics of MPs demonstrated strong correlations within the bottom water and sediment, which might be due to the frequent exchange of materials. In addition, the abundance of MPs was significantly positively correlated with HMs (Cd, Cr, Pb) in the bottom water and PBDEs in sediment, respectively. According to the scanning electron microscopy/energy dispersive X-ray spectrometry analysis, MPs might act as carriers to transport and co-sediment the co-existing pollutants in water, and physically adsorb or chemically bind with pollutants in sediment. These results could help to elucidate the sources, migration, and fate, and verify the occurrence and potential risks of MPs and their co-existing pollutants in BBL, thus realize the management and control of MPs contamination in marine.

In Vitro Potential of Antioxidant Extracts from Gracilaria gracilis Cultivated in Integrated Multi-Trophic Aquaculture (IMTA) for Marine Biobased Sector

This study aimed to evaluate the antioxidant activity of bioactive compounds extracted from Gracilaria gracilis cultivated in an integrated multi-trophic aquaculture (IMTA) system by different extraction solvents and to investigate the potential capacity of the extracts in cellular systems against environmental pollutants. The global yields, total polyphenol contents, and antioxidant activity were assessed on G. gracilis by DPPH radical scavenging activity, comparing the antioxidant extraction efficiency of the different solvents (ethanol 80%, acetone 70%, N-hexane, and water). Ethanol extract, granted by the highest extractive yield and antioxidant capacity, was tested in vitro in the Sparus aurata fibroblast (SAF-1) cell line to evaluate its protective role against oxidative stress induced by the chemical flame retardant 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47). The results demonstrate that the cells pretreated with G. gracilis extract were protected against oxidative stress and had improved cell viability, cellular antioxidant defense system, and cell cycle control, as demonstrated by the gene expression on some biomarkers related to the cell cycle (p53) and oxidative stress (nrf2, sod, and cat). These results confirm that bioactive compounds obtained from seaweeds cultivated in IMTAs could contribute to producing high-value ingredients that are able to counteract environmental stressors, for the growth of the marine biobased industrial sector and the expansion of new value chains.

Long-term contamination of decabromodiphenyl ether reduces sediment multifunctionality: Insights from nutrient cycling, microbial ecological clusters, and microbial co-occurrence patterns

Despite the widespread detection of polybrominated diphenyl ethers in aquatic ecosystems, their long-term effects on sediment multifunctionality remain unclear. Herein, a 360-day microcosm experiment was conducted to investigate how decabromodiphenyl ether (BDE-209) contamination at different levels (0.2, 2, and 20 mg/kg dry weight) affects sediment multifunctionality, focusing on carbon (C), nitrogen (N), phosphorus (P), and sulfur (S) cycling. Results showed that BDE-209 significantly increased sediment total organic carbon, nitrate, ammonium, available phosphorus, and sulfide concentrations, but decreased sulfate. Additionally, BDE-209 significantly altered key enzyme activities related to nutrient cycling. Bacterial community dissimilarity was positively correlated with nutrient variability. Long-term BDE-209 exposure inhibited C degradation, P transport and regulation, and most N metabolic pathways, but enhanced C fixation, methanogenesis, organic P mineralization, inorganic P solubilization, and dissimilatory sulfate reduction pathways. These changes were mainly regulated by microbial ecological clusters and keystone taxa. Overall, sediment multifunctionality declined under BDE-209 stress, primarily related to microbial co-occurrence network complexity and ecological cluster diversity. Interestingly, sediment C and N cycling had greater impacts on multifunctionality than P and S cycling. This study provides crucial insights into the key factors altering multifunctionality in contaminated sediments, which will aid pollution control and mitigation in aquatic ecosystems.

Developmental exposures to common environmental pollutants result in long-term Reprogramming of hypothalamic-pituitary axis in mice

Humans are exposed to a range of endocrine disrupting chemicals (EDCs). Many studies demonstrate that exposures to EDCs during critical windows of development can permanently affect endocrine health outcomes. Most experimental studies address changes in secretion of hormones produced by gonads, thyroid gland and adrenals, and little is known about the ability of EDCs to produce long-term changes in the hypothalamic-pituitary (HP) control axes. Here, we examined the long-term effects of three common EDCs on male mouse HP gene expression, following developmental exposures. Pregnant mice were exposed to 0.2 mg/ml solutions of bisphenol S (BPS), 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47), or 3,3′,5,5′-tetrabromobisphenol A (TBBPA) from pregnancy day 8 through lactation day 21 (weaning day). Male offspring were left untreated until postnatal day 140, where pituitaries and hypothalami were collected. Pituitaries were assed for gene expression via RNA sequencing, while specific genes were assessed for expression in hypothalami via RT-qPCR. Differential expression, as well as gene enrichment and pathway analysis, indicated that all three chemicals induced long-term changes, (mostly suppression) in pituitary genes involved in its endocrine function. BPS and BDE-47 produced effects overlapping significantly at the level of effected genes and pathways. All three chemicals altered pathways of gonad and liver HP axes, while BPS altered HP-adrenal and BDE-47 altered HP-thyroid pathways specifically. All three chemicals reduced expression of immune genes in the pituitaries. Targeted gene expression in the hypothalamus indicates down regulation of hypothalamic endocrine control genes by BPS and BDE-47 groups, concordant with changes in the pituitary, suggesting that these chemicals suppress overall HP endocrine function. Interestingly, all three chemicals altered pituitary genes of GPCR-mediated intracellular signaling molecules, key signalers common to many pituitary responses to hormones. The results of this study show that developmental exposures to common EDCs have long-term impacts on hormonal feedback control at the hypothalamic-pituitary level.

P21-23 First data on polybrominated diphenyl ethers occurrence and a follow-up on polychlorinated biphenyl levels in European brown bear as a bioindicator of terrestrial environment contamination

P21-23 First data on polybrominated diphenyl ethers occurrence and a follow-up on polychlorinated biphenyl levels in European brown bear as a bioindicator of terrestrial environment contamination

Polybrominated diphenyl ethers in paired dust-breast milk samples: Levels, predictors of contamination, and health risk assessment for infants and mothers

An integrated study on the levels of 7 polybrominated diphenyl ethers (PBDEs) in house dust and breast milk samples from women (N = 30) living in these households was conducted. ∑PBDEs ranged from <LOD to 523 ng g−1 dust (median 4.9 ng g−1 dust), and from 0.16 to 6.3 ng g−1 lipid weight (lw) (median 0.49 ng g−1 lw), in house dust and breast milk samples, respectively. Statistically significant correlations were observed between the mass fractions of BDE-153 from breast milk, and BDE-47, BDE-99 and BDE-100 from house dust, congeners that all originate from the “penta” formulation, indicating its dominance as PBDE exposure source in the examined household dusts. The number of electronic and electrical devices, and age of the building were positive, and the number of upholstered furniture and household area were negative predictors of PBDE dust levels. Mothers age was negative predictor of the PBDE levels in breast milk, possibly due to dilution of PBDEs in total body fat accumulated over the years. The results of health risk assessment suggest that detected PBDE levels don’t pose non-carcinogenic risk to the study population.

Occurrence, source identification and risk assessment of polybrominated diphenyl ethers in water and sediments of Osun River, Nigeria

BackgroundIn the present study, the concentrations of polybrominated diphenyl ethers (PBDEs) in water and sediments of Osun River, Nigeria were determined.MethodsThe obtained water samples were subjected to liquid-liquid extraction while the sediment samples were subjected to extraction using n-hexane and acetone. The extracts were quantified using a Gas Chromatography-Mass Spectrometer to assess their distribution, source identification, and ecological risk assessments.ResultsThe results of the study indicated that BDE-99, BDE-183, and BDE-209 were not detected in the water samples while BDE-28 had the most significant mean contribution (0.057 mg/L w.w) to the total PBDEs in the water samples. The sediment samples were dominated by enhanced concentrations of BDE-100 congener (mean concentration 0.184 mg/kg d.w). The compositional profiles of the PBDE congeners indicated the abundance of higher BDEs in the sediment samples compared to the water samples, a phenomenon attributed to the lower reduction rate and lower water solubility of the higher BDEs. Source identification indicated that commercial deca-BDE mixtures might represent the major source of PBDEs in the studied river. Risk assessment of PBDEs in water samples showed that the mean concentrations of tri-BDE, tetra-BDE, penta-BDE, and hexa-BDE exceeded the acceptable limits, suggesting adverse health risks to the public. Ecological risk assessment of PBDEs in sediment samples showed medium ecological risk by hexa-BDE (0.1 ≤ RQ ≤ 1) and high ecological risks due to tri-, tetra-, penta-, and deca-BDEs (RQ > 1).ConclusionThe study concludes that efficient and cost-effective remediation strategies should be developed and employed in the abatement of these persistent organic pollutants from the environment.

Persistent endocrine-disrupting chemicals and incident uterine leiomyomata: A mixtures analysis

BackgroundUterine leiomyomata (UL; fibroids) are hormone-dependent neoplasms that can cause significant gynecologic morbidity. Studies have documented associations between concentrations of persistent endocrine-disrupting chemicals (EDCs) and UL incidence; however, few have assessed the effects of EDC mixtures on UL. MethodsIn the Study of Environment, Lifestyle, and Fibroids, a prospective cohort study, participants attended study visits at baseline and approximately every 20 months for up to 10 years; at each visit, they completed questionnaires, provided blood samples, and underwent standardized ultrasound examinations. In baseline plasma samples (n = 1155), we quantified concentrations of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and organochlorine pesticides using high-resolution mass spectrometry. We selected nine EDCs detected in >60 % of samples (4 PCBs, 4 PBDEs, and 2,2-bis(4-chlorophenyl)-1,1-dichloroethene (p,p’-DDE)) and conducted probit Bayesian kernel machine regression with hierarchical variable selection to estimate effects of the EDC mixture and individual EDCs on UL incidence, adjusting for potential confounders. ResultsDuring 10 years of follow-up, 32 % of participants developed ultrasound-detected UL. The EDC mixture was not appreciably associated with the probit of UL (β comparing all EDCs at their 75th vs. 50th percentile:= − 0.01, 95 % credible interval [CrI]: −0.11, 0.10). However, individual EDC concentrations were associated with UL in opposing directions: PCB138/158 was positively associated with UL (β for 25th-to-75th-percentile increase when all other chemicals were set to their 50th percentile = 0.18, 95 % CrI: −0.09, 0.44), whereas PBDE99 and p,p’-DDE were inversely associated with UL (β = −0.06, 95 % CrI: −0.21, 0.10 and β = −0.12, 95 % CrI: −0.34, 0.10, respectively). There was little evidence of interaction between EDCs. ConclusionIn this prospective ultrasound study, a mixture of persistent EDCs was not appreciably associated with incident UL during 10 years of follow-up, but individual EDCs were associated with UL in opposite directions.

Uptake of Typical Hydrophobic Organic Contaminants in Vegetables: Evidence From Passive Samplers.

Quantifying the root uptake of hydrophobic organic contaminants (HOCs) by plants remains challenging due to the lack of data on the freely available fractions of HOCs in soil porewater. We therefore hypothesized that a passive sampler could act as a useful tool to evaluate the root uptake potential and pathways of HOCs by plants in soil. We tested this hypothesis by exploring the uptake of polybrominated diphenyl ethers (PBDEs) and organophosphate esters (OPEs) by carrot and lettuce with the codeployment of passive samplers in a contaminated soil system. The results showed that the amounts of PBDEs enriched in carrot and lettuce were positively correlated with those in a passive sampler (r2 = 0.46-0.88). No concentration correlation was observed for OPEs between lettuce and passive samplers, due to possible degradation of OPEs in lettuce. The root-to-porewater ratios of PBDEs and OPEs, respectively, were 6.2 to 11 and 0.05 to 0.88 L g-1 for carrot, and 8.8 to 130 and less than reporting limits to 1.2 L g-1 for lettuce. The ratios were negatively correlated with log KOW values for carrot, but increased with increasing log KOW values over a range of 1.97 to 6.80, and then decreased with log KOW values greater than 6.80 for lettuce. This finding indicated that passive transport and partition were the accumulation pathways of PBDEs and OPEs in carrot and lettuce, respectively. Overall, passive samplers performed adequately in assessing the available fractions of persistent HOCs in plants, and can serve as a viable tool for exploring the pathways for plant root uptake of HOCs. Environ Toxicol Chem 2024;43:2338-2349. © 2024 SETAC.

Identification of serum metabolites associated with polybrominated diphenyl ethers (PBDEs) exposure in papillary thyroid carcinoma: a case–control study

As the most common endocrine cancer, thyroid cancer (TC) has sharply increased globally over the past three decades. The growing incidence of TC might be counted by genetics, radiation, iodine, autoimmune disease, and exposure to environmental endocrine–disrupting chemicals (EDCs). Polybrominated diphenyl ethers (PBDEs), being typical EDCs, have been widely utilized in plastics, electronics, furniture, and textiles as flame retardants since the 1980s, and research has indicated a significant correlation between their exposure and the risk of TC. Even so, PBDEs exposure impact on the metabolic signature for TC remains unexplored. In this study, eight congeners of PBDEs were determined in serum from 111 patents with papillary thyroid cancer (PTC) and 111 healthy participants based on case–control epidemiology using gas chromatography–atmospheric pressure chemical ionization–tandem mass spectrometry (GC-APCI–MS/MS). Based on the tertile distribution of total PBDEs concentrations in 59 participants, metabolomics analysis was further performed by ultra-high performance liquid chromatography coupled to hybrid quadrupole–Orbitrap MS. In the partial correlation analysis, the 29 identified metabolites were correlated with PBDEs exposure (P < 0.05). In addition, PBDEs disrupted the metabolism of glycerophospholipids, sphingolipids, taurine, and hypotaurine, indicating that neurotransmitters, oxidative stress, and inflammation are the vulnerable pathways affected in PTC. Furthermore, (±)-octopamine and 5-hydroxyindole, both of which modulate the actions of neurotransmitters, emerged as potential disturbed metabolite markers for TC following exposure to PBDEs. This study analyzed the impact of PBDEs on PTC in terms of the metabolic changes and further explored possible biomarkers, which helped us have a deep understanding of the possible mechanism of the effects of PBDEs on TC.

Biofilm formation on MgFe-LDH@quartz sand as novel wetland substrate under varied C/N ratios for BDE-47 removal

Layered double hydroxide (LDH)-coated substrates could enhance the removal of various wastewater-born pollutants. However, research on biofilms attached to LDH-coatings and their synergistic purification effects on strongly hydrophobic persistent organic pollutants (POPs) remains limited. This study aims to investigate biofilm formation on MgFe-LDH@quartz sand and its effectiveness in removing tetrabromodiphenyl ether (BDE-47), an emerging halogenated POP in municipal wastewater. Under different C/N ratios (3, 5, and 10), BDE-47 removal rates ranged from 28.0% to 41.6% after 72 h. The optimal performance was achieved with LDH coating at C/N = 5, when substrate biofilm reached its highest extracelluar polymer substances (EPS) content, dehydrogenase activity and relative hydrophobicity. Moreover, distinct distribution patterns of EPS components’ fluorescence peaks were observed in the LDH-coating treatment using three dimensional excitation-emission matrix (3D-EEM). While substrate adsorption was the primary mechanism for BDE-47 removal, accounting for 59.6%–83.4% of the total, biofilm adsorption and degradation contributed a relatively lower amount, ranging from 11.5% to 21.4%, and were more dependent on the C/N ratio. Notably, the maximum carrying capacity of protein predicted by the logistic growth model exhibited a strong positive correlation with the total BDE-47 removal rate (R2 = 0.82, p < 0.05), highlighting the importance of biofilm extracelluar proteins.

Screening persistent organic pollutants for effects on testosterone and estrogen synthesis at human-relevant concentrations using H295R cells in 96-well plates.

Many persistent organic pollutants (POPs) are suspected endocrine disruptors and it is important to investigate their effects at low concentrations relevant to human exposure. Here, the OECD test guideline #456 steroidogenesis assay was downscaled to a 96-well microplate format to screen 24 POPs for their effects on viability, and testosterone and estradiol synthesis using the human adrenocortical cell line H295R. The compounds (six polyfluoroalkyl substances, five organochlorine pesticides, ten polychlorinated biphenyls and three polybrominated diphenyl ethers) were tested at human-relevant levels (1 nM to 10 µM). Increased estradiol synthesis, above the OECD guideline threshold of 1.5-fold solvent control, was shown after exposure to 10 µM PCB-156 (153%) and PCB-180 (196%). Interestingly, the base hormone synthesis varied depending on the cell batch. An alternative data analysis using a linear mixed-effects model that include multiple independent experiments and considers batch-dependent variation was therefore applied. This approach revealed small but statistically significant effects on estradiol or testosterone synthesis for 17 compounds. Increased testosterone levels were demonstrated even at 1 nM for PCB-74 (18%), PCB-99 (29%), PCB-118 (16%), PCB-138 (19%), PCB-180 (22%), and PBDE-153 (21%). The MTT assay revealed significant effects on cell viability after exposure to 1 nM of perfluoroundecanoic acid (12%), 3 nM PBDE-153 (9%), and 10 µM of PCB-156 (6%). This shows that some POPs can interfere with endocrine signaling at concentrations found in human blood, highlighting the need for further investigation into the toxicological mechanisms of POPs and their mixtures at low concentrations relevant to human exposure.

Determination of Anthropogenic Pollutants in Adipose Tissue of the Caspian Seal Pusa caspica Gmelin, 1788 by High-Resolution Accurate Mass Spectrometry.

Tissue contamination with persistent organic pollutants (POPs) in organisms proved possible to comprehensively characterize in a single test by combining gas chromatography and high-resolution accurate mass spectrometry. Adipose tissue samples were collected from two Caspian seals (Pusa caspica Gmelin, 1788) found dead on the Caspian Sea shore in 2020. Organochlorine pesticides, primarily DDT and HCH, and polychlorinated biphenyls (PCBs) were major pollutants found in the Caspian seals. The distribution of metabolites indicated the absence of recent pesticide use. The PCB content was relatively high, but still at the lower limit of the range of values determined previously, as was also the case with pesticides. Chlordanes, polychlorinated naphthalenes, and polybrominated diphenyl ethers were detected in minor quantities and were therefore not considered to be major pollutants of the Caspian seal. The pollutant levels were below a threshold at which a distinct effect on seal health can be expected. High-resolution accurate mass (HRAM) spectrometry was found to provide a convenient tool for both targeted and nontargeted analyses of a wide range of organic pollutants in a single experiment.

Visual toxicity in zebrafish larvae following exposure to 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47), triphenyl phosphate (TPhP), and isopropyl phenyl diphenyl phosphate (IPPP)

TPhP and IPPP, alternatives to PBDEs as flame retardants, have been studied for their developmental toxicity, but their visual toxicities are less understood. In this study, zebrafish larvae were exploited to evaluate the potential ocular impairments following exposure to BDE-47, TPhP, and IPPP. The results revealed a range of ocular abnormalities, including malformation, vascular issues within the eyes, and histopathological changes in the retina. Notably, the visually mediated behavioral changes were primarily observed in IPPP and TPhP, indicating that they caused more severe eye malformations and vision impairment than BDE-47. Molecular docking and MD simulations showed stronger binding affinity of TPhP and IPPP to RAR and RBP receptors. Elevated ROS and T3 levels induced by these compounds led to apoptosis in larvae eyes, and increased GABA levels induced by TPhP and IPPP hindered retinal repair. In summary, our results indicate TPhP and IPPP exhibit severer visual toxicity than BDE-47, affecting eye development and visually guided behaviors. The underlying mechanism involves disruptions in RA signaling, retinal neurotransmitters imbalance, thyroid hormones up-regulation, and apoptosis in larvae eyes. This work highlights novel insights into the need for cautious use of these flame retardants due to their potential biological hazards, thereby offering valuable guidance for their safer applications.

Mitigation of PBDE net discharge in hazardous waste thermal treatment system through reintroducion of sludge and fly ash into GASMILD operations

The presence of polybrominated diphenyl ethers (PBDEs) in consumer products, waste treatment processes, and treated ashes poses a significant environmental threat. Due to the lack of research on the removal of PBDEs during waste incineration, this study investigated the effectiveness of a Hazardous Waste Thermal Treatment System (HAWTTS) utilizing reburning of sludge and fly ash (SFA) with gasification-moderate or intense low-oxygen dilution (GASMILD) combustion for PBDE removal. The closed-loop treatment of sludge and ash within the HAWTTS provides a potential pathway for near-zero PBDE emissions. The GASMILD combustion addresses potential combustion issues associated with fly ash recirculation. The system achieved an impressive overall removal efficiency of 98.4% for PBDEs, with minimal stack emissions (2.45 ng/Nm³) and a negative net discharge rate (−1.02 μg/h). GASMILD combustion played a crucial role (92.7%–97.6% destruction) in addressing challenges associated with high-moisture feedstocks and SFA residues. Debromination of highly brominated PBDEs occurred within the incinerator, resulting in an increased proportion of lower brominated PBDEs in the bottom slag compared to the feedstock. Air Pollution Control Devices (APCDs) achieved a total PBDE removal efficiency of 74.4%. However, the hydrophobic nature of PBDEs limited removal efficiency in scrubbers (36.0%) and cyclonic demisters (37.86%). This study demonstrates that reintroducing SFA into the GASMILD combustion process offers an effective and environmentally sustainable strategy for reducing net PBDE levels in hazardous waste. This approach also provides additional benefits such as energy conservation, reduced carbon emissions, and lower operating costs associated with secondary treatment of thermally treated byproducts.

Maternal Exposure to Low-Dose BDE-47 Induced Weight Gain and Impaired Insulin Sensitivity in the Offspring.

Polybrominated diphenyl ethers (PBDEs), commonly used as synthetic flame retardants, are present in a variety of consumer products, including electronics, polyurethane foams, textiles, and building materials. Initial evidence from epidemiological and experimental studies suggests that maternal PBDE exposure may be associated with a higher BMI in children, with disturbance of energy metabolism and an increased risk of Type 2 diabetes. However, the causality between early exposure to real-life PBDE concentrations and increased weight as well as mechanisms underlying impaired metabolic pathways in the offspring remain elusive. Here, using a mouse model we examined the effect of maternal exposure to 2,2',4,4'-tetrabrominated diphenyl ether (BDE-47), the most abundant congener in human samples, on offspring weight gain and energy homeostasis using a mouse model. Maternal exposure to BDE-47 at low dose resulted in weight gain in female offspring together with an impaired glucose and insulin tolerance in both female and male mice. In vitro and in vivo data suggest increased adipogenesis induced by BDE-47, possibly mediated by DNA hypermethylation. Furthermore, mRNA data suggest that neuronal dysregulation of energy homeostasis, driven via a disturbed leptin signaling may contribute to the observed weight gain as well as impaired insulin and glucose tolerance.

Plastisphere Microbiomes Respiring Persistent Organohalide Pollutants.

Plastics are invading nearly all ecosystems on earth, acting as emerging repositories for toxic organic pollutants and thereby imposing substantial threats to ecological integrity. The colonization of plastics by microorganisms, forming the plastisphere, has garnered attention due to its potential influence on biogeochemical cycles. However, the capability of plastisphere microorganisms to attenuate organohalide pollutants remains to be evaluated. This study revealed that the plastisphere, collected from coastal ecosystems, harbors unique microbiomes, while the natural accumulation of organohalide pollutants on plastics may favor the proliferation of organohalide-respiring bacteria (OHRB). Laboratory tests further elucidated the high potential of plastisphere microbiota to reductively dehalogenate a variety of organohalide pollutants. Notably, over 70% tested plastisphere completely debrominated tetrabromobisphenol A (TBBPA) and polybrominated diphenyl ethers (PBDEs) to nonhalogenated products, whereas polychlorinated biphenyls (PCBs) were converted to lower congeners under anaerobic conditions. Dehalococcoides, Dehalogenimonas, and novel Dehalococcoidia populations might contribute to the observed dehalogenation based on their growth during incubation and positive correlations with the quantity of halogens removed. Intriguingly, large fractions of these OHRB populations were identified in a lack of the currently known TBBPA/PBDEs/PCBs reductive dehalogenase (RDase) genes, suggesting the presence of novel RDase genes. Microbial community analyses identified organohalides as a crucial factor in determining the composition, diversity, interaction, and assembly of microbes derived from the plastisphere. Collectively, this study underscores the overlooked roles of the plastisphere in the natural attenuation of persistent organohalide pollutants and sheds light on the unignorable impacts of organohalide compounds on the microbial ecology of the plastisphere.

A review on e-waste contamination, toxicity, and sustainable clean-up approaches for its management

Ecosystems and human health are being negatively impacted by the growing problem of electrical waste, especially in developing countries. E-waste poses a significant risk to ecological systems because it can release a variety of hazardous substances into the environment, containing polybrominated diphenyl ethers and heavy metals, brominated flame retardants, polychlorinated dibenzofurans and polycyclic aromatic hydrocarbons, and dioxins. This review article provides a critical assessment of the toxicological consequences of e-waste on ecosystems and human health and data analyses from scientific journals and grey literature on metals, BFRs, PBDEs, PCDFs, and PAHs in several environmental compartments of commercial significance in informal electronic trash recycling. The currently available techniques and tools employed for treating e-waste are sustainable techniques such as bioremediation, chemical leaching, biological leaching, and pyrometallurgy have been also discussed along with the necessity of implementing strong legislation to address the issue of unregulated exports of electronic trash in recycling practices. Despite the ongoing hurdles, implementing environmentally sustainable recycling methods have the potential to address the detrimental impacts of e-waste and foster positive economic development.

Contaminant levels versus toxicity bioassays in ecological risk assessment of sediments from the southern Baltic Sea

Surface sediments collected in 2021 from six locations in the southern Baltic Sea (Polish district) were examined by chemical and toxicological methods. Chemical analyses included polybrominated diphenyl ethers (PBDEs), polycyclic aromatic hydrocarbons (PAHs), and their alkylated derivatives, butyltin compounds and 16 major and trace elements. The toxicity was measured using Ostracodtoxkit F and Microtox. The ecological risk of sediment was estimated by hazard quotient (HQ) calculation. Some PAHs, alkylated PAHs and metals (Zn, Hg, Cd and As) could pose a moderate risk in the sediments from the Gdańsk Deep and in the vicinity of the wrecks, but the risk resulting from the presence of all analyzed compounds was considered high for these sediments. In studies using biotests, sediments from the vicinity of the t/s Franken wreck and the Słupsk Furrow were highly toxic to test organisms. Ostracodtoxkit F, compared to Microtox, appeared a more sensitive test for measured compounds.