Optimization and uncertainty assessment of a gas chromatography coupled to Orbitrap mass spectrometry method to determine organic contaminants in blood: A case study of an endangered seabird.

Birds are excellent bioindicators of environmental pollution, and blood provides information on contaminant exposure, although its analysis is challenging because of the low volumes that can be sampled. The objective of the present study was to optimize and validate a miniaturized and functional extraction and analytical method based on gas chromatography coupled to Orbitrap mass spectrometry (GCOrbitrap-MS) for the trace analysis of contaminants in avian blood. Studied compounds included 25 organochlorine pesticides (OCPs), 6 polychlorinated biphenyls (PCBs), 8 polybrominated diphenyl ethers (PBDEs) and 15 polycyclic aromatic hydrocarbons (PAHs). Four extraction and clean-up conditions were optimized and compared in terms of efficiency, accuracy, and uncertainty assessment. Extraction with hexane:dichloromethane and miniaturized Florisil pipette clean-up was the most adequate considering precision and accuracy, time, and costs, and was thereafter used to analyse 20 blood samples of a pelagic seabird, namely the Bermuda petrel (Pterodroma cahow). This species, endemic to the Northwest Atlantic, is among the most endangered seabirds of the region that in the '60 faced a decrease in the breeding success likely linked to a consistent exposure to dichloro-diphenyl-trichloroethane (DDT). Indeed, p,p'-DDE, the main DDT metabolite, was detected in all samples and ranged bewteen 1.13 and 6.87 ng/g wet weight. Other ubiquitous compounds were PCBs (ranging from 0.13 to 6.76 ng/g ww), hexachlorobenzene, and mirex, while PAHs were sporadically detected at low concentrations, and PBDEs were not present. Overall, the extraction method herein proposed allowed analysing very small blood volumes (∼ 100 µL), thus respecting ethical principles prioritising the application of less-invasive sampling protocols, fundamental when studying threatened avian species.

Exposure to Polybrominated Diphenyl Ethers and Risk of All-Cause and Cause-Specific Mortality.

Importance: Polybrominated diphenyl ethers (PBDEs) are an important group of persistent organic pollutants with endocrine-disrupting properties. However, prospective cohort studies regarding the association of PBDE exposure with long-term health outcomes, particularly mortality, are lacking. Objective: To examine the association of environmental exposure to PBDEs with risk of all-cause and cause-specific mortality. Design, Setting, and Participants: This nationally representative cohort study used data from the National Health and Nutrition Examination Survey 2003 to 2004 and linked mortality information through December 31, 2019. Adults aged 20 years or older with available data on PBDE measurements and mortality were included. Statistical analysis was performed from February 2022 to April 2023. Exposures: PBDE analytes in serum samples were measured using solid phase extraction and isotope dilution gas chromatography high-resolution mass spectrometry. Main Outcomes and Measures: All-cause mortality, cancer mortality, and cardiovascular mortality. Results: This study included 1100 participants (mean [SE] age, 42.9 [0.6] years; proportion [SE] female, 51.8% [1.6%]; proportion [SE] Hispanic, 12.9% [2.7%]; proportion [SE] non-Hispanic Black, 10.5% [1.6%]; proportion [SE] non-Hispanic White, 70.8% [3.7%]; proportion [SE] other race and ethnicity, 5.8% [1.1%]). During 16 162 person-years of follow-up (median [IQR] follow-up, 15.8 [15.2-16.3] years; maximum follow-up, 17 years), 199 deaths occurred. Participants with higher serum PBDE levels were at higher risk for death. After adjustment for age, sex, and race and ethnicity, lifestyle and socioeconomic factors, and body mass index, participants with the highest tertile of serum PBDE levels had an approximately 300% increased risk of cancer mortality (HR, 4.09 [95% CI, 1.71-9.79]) compared with those with the lowest tertile of serum PBDE levels. No significant association of PBDE exposure with all-cause mortality (HR, 1.43 [95% CI, 0.98-2.07]) or cardiovascular mortality (HR, 0.92 [95% CI, 0.41-2.08]) was observed. Conclusions and Relevance: In this nationally representative cohort study, PBDE exposure was significantly associated with an increased risk of cancer mortality. Further studies are needed to replicate the findings and determine the underlying mechanisms.

Variations in thyroid hormone levels in endangered St. Lawrence Estuary belugas: Potential linkage with stress and organohalogen contaminant exposure.

The St. Lawrence Estuary (SLE) beluga (Delphinapterus leucas) population is highly exposed to an array of contaminants that were identified as one of the causes to the non-recovery of this endangered and declining population. In the last decade, an increasing number of parturition-associated complications and calf mortality has been reported in this population. It was suggested that elevated exposure to organohalogens (e.g., the halogenated flame retardants polybrominated diphenyl ethers [PBDEs]) and stress could play a role in this phenomenon by perturbing thyroid hormones. The objective of this study was to investigate the impact of concentrations of organohalogen contaminants and stress (cortisol levels) on thyroid hormone variations in adult male and female SLE belugas. Because plasma could not be collected in SLE belugas for ethical reasons, skin biopsy (n = 40) was used as a less-invasive alternative matrix to determine organohalogens (PBDEs and other halogenated flame retardants, polychlorinated biphenyls, and organochlorine pesticides), cortisol, and thyroid hormones (triiodothyronine [T3] and thyroxine [T4]), and their metabolites reverse T3 and 3,5-diiodothyronine [3,5-T2]). Cortisol and thyroid hormones were analyzed by ultra-performance liquid chromatography-multiple reactions monitoring mass spectrometry (UPLC-MRM/MS). This method was compared using skin and plasma samples obtained from Arctic belugas. Comparisons of linear models showed that cortisol was a weak predictor for T4, rT3 and 3,5-T2. Specifically, there was a weak significant negative association between T4 and cortisol levels. Moreover, in male SLE belugas, a weak significant positive association was found between T3 and Σ34PBDE concentrations in skin. Our findings suggest that stress (i.e., elevated skin cortisol levels) along with organohalogen exposure (mainly PBDEs) may be associated with thyroid hormone level perturbations in skin of cetaceans.

Assessment of human dermal absorption of flame retardant additives in polyethylene and polypropylene microplastics using 3D human skin equivalent models.

To overcome ethical and technical challenges impeding the study of human dermal uptake of chemical additives present in microplastics (MPs), we employed 3D human skin equivalent (3D-HSE) models to provide first insights into the dermal bioavailability of polybrominated diphenyl ether (PBDEs) present in MPs; and evaluated different factors influencing human percutaneous absorption of PBDEs under real-life exposure scenario. PBDEs were bioavailable to varying degrees (up to 8 % of the exposure dose) and percutaneous permeation was evident, albeit at low levels (≤0.1 % of the exposure dose). While the polymer type influenced the release of PBDEs from the studied MPs to the skin, the polymer type was less important in driving the percutaneous absorption of PBDEs. The absorbed fraction of PBDEs was strongly correlated (r2 = 0.88) with their water solubility, while the dermal permeation coefficient Papp of PBDEs showed strong association with their molecular weight and logKOW. More sweaty skin resulted in higher bioavailability of PBDEs from dermal contact with MPs than dry skin. Overall, percutaneous absorption of PBDEs upon skin contact with MPs was evident, highlighting, for the first time, the potential significance of the dermal pathway as an important route of human exposure to toxic additive chemicals in MPs.

Contamination levels, influencing factors, and risk assessment of polybrominated diphenyl ethers in house dust of northern Serbia.

Polybrominated diphenyl ethers (PBDEs) are a group of compounds that, due to their applications, are considered mainly indoor contaminants. To obtain the first information about the presence of PBDEs in Serbia, dust samples (n = 50) were collected in settlements in the northern Serbian province of Vojvodina. The selected/target congeners (BDE-28, 47, 99, 100, 153, 154, and 183) were extracted from house dust by microwave-assisted extraction technique, and purified extracts were analyzed on a dual-column gas chromatograph with micro-electron capture detectors. A wide range of ΣPBDEs was detected (0.295 to 394 ng g-1 dust), which reflects large differences in contamination among the examined homes. For the majority of samples (72%), ΣPBDEs were lower than 5 ng g-1 indicating that people living in Vojvodina province are exposed to low concentrations of PBDEs present in their households. Based on principal component analysis (PCA), balcony areas and age of the house positively correlate with the PBDE congeners with higher detection frequencies (≥ 50%), namely, with BDE-99, BDE-153, and BDE-183. Statistically significant positive correlation (p < 0.01) was obtained for BDE-99 and the number of household's members. Estimated daily intakes (EDItot) were calculated for ingestion and dermal absorption of dust for two age groups-adults and toddlers. These are the first data on PBDE status in the area of the Western Balkan, and the health risk assessment indicates that PBDE levels obtained in household dust do not pose a risk for human health.

BDE-47-induced damage prevented by melatonin in grass carp hepatocytes (L8824).

Polybrominated diphenyl ethers (PBDEs) are toxic to organisms with melatonin (MT) providing protection for tissues and cells against these. This study investigates the mechanism of damage of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) and the cellular protection of MT on grass carp hepatocytes. Grass carp hepatocytes were exposed to 25 µmol/L BDE-47 and/or 40 µmol/L MT for 24 h before testing. Acridine orange/ethidium bromide (AO/EB) double fluorescence staining results showed that BDE-47 could induce cell apoptosis. The expression levels of the endoplasmic reticulum (ER) stress-related genes ire1, atf4, grp78, perk, and chop were also significantly up-regulated (P < 0.01). The levels of the apoptosis-related genes caspase3, bax, and caspase9 were significantly up-regulated (P < 0.0001), while the level of bcl-2 was significantly down-regulated (P < 0.01). Compared with the BDE-47 group, the BDE-47 + MT group showed reduced levels of ER and apoptosis of hepatocytes, while the expression of the ER stress-related genes ire1, atf4, grp78, perk, and chop and the apoptosis-related genes caspase3, bax, and caspase9 were down-regulated (P < 0.05), and the level of bcl-2 was up-regulated (P < 0.01). In conclusion, BDE-47 can activate ER and apoptosis in grass carp hepatocytes, while MT can reduce these responses.

Tourmaline-enhanced bioremediation of Cd/BDE-153 co-contaminated soil: Migration, soil microorganism structure and enzyme activities.

The efficient remediation of the soil co-contaminated with heavy metals and polybrominated diphenyl ethers (PBDEs) from electronic disassembly zones is a new challenge. Here, we screened a fungus of F. solani (F.s) can immobilize Cd and remove PBDEs. wIt combined with tourmaline enhances the remediation of co- pollutants in the soil. Furthermore, the environment risks of the enhanced technology were assessed through the amount of Cd/BDE-153 in Amaranthus tricolor L. (amaranth) migrated from soil, as well as the changes of soil microorganism communities and enzyme activities. The results showed the combined treatment of tourmaline and F.s made the removal percentage of BDE-153 in rhizosphere soil co-contaminated with BDE-153 and Cd reached 46.5%. And the weak acid extractable Cd in rhizosphere soil decreased by 33.7% compared to control group. In addition, the combined remediation technology resulted in a 32.5% (22.8%), 45.5% (37.2%), and 50.7% (38.1%) decrease in BDE-153 (Cd) content in the roots, stems, and leaves of amaranth, respectively. Tourmaline combined with F.s can significantly increase soil microorganism diversity, soil dehydrogenase and urease activities, further improving the remediation rate of Cd and BDE-153co-pollutants in soil and the biomass of amaranth. This study provides the remediation technology of soil co-contaminated with heavy metal and PBDEs and ensure the maintenance of food security.

The role of Sertoli cells-secreted factors in different stages of germ cells development in mice exposed to BDE-209.

Decabromodiphenyl ether (BDE-209), a frequently used brominated flame retardant, readily enters the environment and is difficult to degrade with bioaccumulation. BDE-209 could cause male reproductive toxicity, but the regulatory functions of Sertoli cells-secreted factors remain uncertain. In present study, male mice were treated with 75 mg/kg BDE-209 and then stopped exposure for 50 days. Exogenous Glial cell line-derived neurotrophic factor (GDNF), a Sertoli cell-secreted factor, was injected into testes of mice treated with BDE-209 for 50 days to explore the role of GDNF in BDE-209-induced reproductive toxicity. The mouse spermatogonia cell line GC-1 spg was used in vitro to further verify regulatory effects of Sertoli cells-secreted factors on meiotic initiation. The results showed that BDE-209 inhibited expressions of the self-renewal pathway GFRα-1/RAS/ERK1/2 in spermatogonial stem cells (SSCs), and reduced expressions of spermatogonia proliferation-related pathway NRG3/ERBB4 and meiosis initiation factor Stra8. Furthermore, BDE-209 decreased the levels of both GDNF and retinoic acid (RA) secreted by Sertoli cells in testes. Importantly, the alterations of above indicators induced by BDE-209 did not recover after 50-day recovery period. After exogenous GDNF injection, the decreased expression of GFRα-1/RAS/ERK in SSCs was reversed. However, the level of RA and expressions of NRG3/ERBB4/Stra8 were not restored. The in vitro experimental results showed that exogenous RA reversed the reductions in NRG3/ERBB4/Stra8 and ameliorated inhibition of GC-1 spg cells proliferation induced by BDE-209. These results suggested that Sertoli cells-secreted factors play roles in regulating various stages of germ cell development. Specifically, BDE-209 affected the self-renewal of SSCs by decreasing GDNF secretion resulting in the inhibition of GFRα-1/RAS/ERK pathway; BDE-209 hindered the proliferation of spermatogonia and initiation of meiosis by inhibiting the secretion of RA and preventing RA from binding to RARα, resulting in the suppression of NRG3/ERBB4/Stra8 pathway. As a consequence, spermatogenesis was compromised, leading to persistent male reproductive toxicity.

Toxicity of persistent organic pollutants: a theoretical study.

CONTEXT: Polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) are two families of persistent organic pollutants that are dangerous as they remain in the atmosphere for long periods and are toxic for humans and animals. They are found all over the world, including the penguins of Antarctica. One of the mechanisms that explains the toxicity of these compounds is related to oxidative stress. The main idea of this theoretical research is to use conceptual density functional theory as a theory of chemical reactivity to analyze the oxidative stress that PCBs and PBDEs can produce. The electron transfer properties as well as the interaction with DNA nitrogenous bases of nine PCBs and ten PBDEs found in Antarctic penguins are investigated. From this study, it can be concluded that compounds with more chlorine or bromine atoms are more oxidizing and produce more oxidative stress. These molecules also interact directly with the nitrogenous bases of DNA, forming hydrogen bonds, and this may be an explanation for the toxicity. Since quinone-type metabolites of PCBs and PBDEs can cause neurotoxicity, examples of quinones are also investigated. Condensed Fukui functions are included to analyze local reactivity. These results are important as the reactivity of these compounds helps to explain the toxicity of PCBs and PBDEs. METHODS: All DFT computations were performed using Gaussian16 at M06-2x/6-311 + g(2d,p) level of theory without symmetry constraints. Electro-donating (ω-) and electro-accepting (ω +) powers were used as global response functions and condensed Fukui functions as local parameters of reactivity.

Novel flame retardants detected in marine plastic litter in coastal areas in Central Chile.

Flame retardants (FRs) are released throughout the plastic life cycle, potentially impacting the environment, biodiversity, and human health. This study analyzed novel flame retardants (NFR) in marine plastic litter (MPL) from six coastal areas in central Chile in November 2017. Target chemicals (n = 19) were analyzed using ultrasonic extraction with hexane, gas chromatography, and mass spectrometry (GC-MS). From all nineteen NFRs analyzed, only ten (53 %) were routinely detected. BTBPE (1,2-bis(2,4,6-tribromophenoxy) ethane) showed the highest concentrations at the Bellavista site (618 to 424,000 pg g-1), and HBB (Hexabromobiphenyl), banned since 1970, was detected in Coliumo (2630 to 13,700 pg g-1). These results show emerging transport patterns and underscore the critical need for enhanced waste management practices for MPL in coastal regions to prevent adverse impacts on marine biodiversity.

Characterization of two novel hydrolases from Sphingopyxis sp. DBS4 for enantioselective degradation of chiral herbicide diclofop-methyl.

Diclofop-methyl, an aryloxyphenoxypropionate (AOPP) herbicide, is a chiral compound with two enantiomers. Microbial detoxification and degradation of various enantiomers is garnering immense research attention. However, enantioselective catabolism of diclofop-methyl has been rarely explored, especially at the molecular level. This study cloned two novel hydrolase genes (dcmA and dcmH) in Sphingopyxis sp. DBS4, and characterized them for diclofop-methyl degradation. DcmA, a member of the amidase superfamily, exhibits 26.1-45.9% identity with functional amidases. Conversely, DcmH corresponded to the DUF3089 domain-containing protein family (a family with unknown function), sharing no significant similarity with other biochemically characterized proteins. DcmA exhibited a broad spectrum of substrates, with preferential hydrolyzation of (R)-(+)-diclofop-methyl, (R)-(+)-quizalofop-ethyl, and (R)-(+)-haloxyfop-methyl. DcmH also preferred (R)-(+)-quizalofop-ethyl and (R)-(+)-haloxyfop-methyl degradation while displaying no apparent enantioselective activity towards diclofop-methyl. Using site-directed mutagenesis and molecular docking, it was determined that Ser175 was the fundamental residue influencing DcmA's activity against the two enantiomers of diclofop-methyl. For the degradation of AOPP herbicides, DcmA is an enantioselective amidase that has never been reported in research. This study provided novel hydrolyzing enzyme resources for the remediation of diclofop-methyl in the environment and deepened the understanding of enantioselective degradation of chiral AOPP herbicides mediated by microbes.

Relationship between flame retardants and respiratory health- A systematic review and meta-analysis of observational studies.

Chronic respiratory diseases are a dealing cause of death and disability worldwide. Their prevalence is steadily increasing and the exposure to environmental contaminants, including Flame Retardants (FRs), is being considered as a possible risk factor. Despite the widespread and continuous exposure to FRs, the role of these contaminants in chronic respiratory diseases is yet not clear. This study aims to systematically review the association between the exposure to FRs and chronic respiratory diseases. Searches were performed using the Cochrane Library, MEDLINE, EMBASE, PUBMED, SCOPUS, ISI Web of Science (Science and Social Science Index), WHO Global Health Library and CINAHL EBSCO. Among the initial 353 articles found, only 9 fulfilled the inclusion criteria and were included. No statistically significant increase in the risk for chronic respiratory diseases with exposure to FRs was found and therefore there is not enough evidence to support that FRs pose a significantly higher risk for the development or worsening of respiratory diseases. However, a non-significant trend for potential hazard was found for asthma and rhinitis/rhinoconjunctivitis, particularly considering urinary organophosphate esters (OPEs) including TNBP, TPHP, TCEP and TCIPP congeners/compounds. Most studies showed a predominance of moderate risk of bias, therefore the global strength of the evidence is low. The limitations of the studies here reviewed, and the potential hazardous effects herein identified highlights the need for good quality large-scale cohort studies in which biomarkers of exposure should be quantified in biological samples.

BDE-99 stimulates generation of aberrant brown/beige adipocytes.

Adipose tissue compromises one of the principal depots where brominated flame retardants (BFR) accumulate in vivo, yet whether BFR disturb thermogenic brown/beige adipocytes is still not referred to date. Herein, effects of BDE-99, a major congener of polybrominated diphenyl ethers (PBDEs) detected in humans, on brown/beige adipocytes were explored for the first time, aiming to provide new knowledge evaluating the obesogenic and metabolic disrupting effects of BFR. Our results firstly demonstrated that exposure to BDE-99 during the lineage commitment period significantly promoted C3H10T1/2 MSCs differentiating into brown/beige adipocytes, evidenced by the increase of brown/beige adipocyte marker UCP1, Cidea as well as mitochondrial membrane potential and basal respiration rate, which was similar to pharmacological PPARγ agonist rosiglitazone. Unexpectedly, the mitochondrial maximal respiration rate of BDE-99 stimulated brown/beige adipocytes was not synchronously enhanced and resulted in a significant reduction of mitochondrial spare respiration capacity (SRC) compared to control or rosiglitazone stimulated adipocytes, indicating a deficient energy-dissipating capacity of BDE-99 stimulated thermogenic adipocytes. Consistently with compromised mitochondrial SRC, lipidomic analysis further revealed that the lipids profile of mitochondria derived from BDE-99 stimulated brown/beige adipocytes were quite different from control or rosiglitazone stimulated cells. In detail, BDE-99 group contains more free fatty acid (FFA) and lyso-PE in mitochondria. In addition to energy metabolism, our results also demonstrated that BDE-99 stimulated brown/beige adipocytes were deficient in endocrine, which secreted more adverse adipokine named resistin, coinciding with comparable beneficial adipokine adiponectin compared with that of rosiglitazone. Taken together, our results showed for the first time that BDE-99 stimulated brown/beige adipocytes were aberrant in energy metabolism and endocrine, which strongly suggests that BDE-99 accumulated in human adipose tissue could interfere with brown/beige adipocytes to contribute to the occurrence of obesity and relevant metabolic disorders.

Dietary exposure to 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) induces oxidative damage promoting cell apoptosis primarily via mitochondrial pathway in the hepatopancreas of carp, Cyprinus carpio.

To investigate the mechanisms of BDE-47 on hepatotoxicity in fish, this study examined the effects of dietary exposure to BDE-47 (40 and 4000 ng/g) on carp for 42 days. The results showed that BDE-47 significantly increased carp's condition factor and hepatosomatic index. Pathological results revealed unclear hepatic cord structure, hepatocytes swelling, cellular vacuolization, and inflammatory cell infiltration in the hepatopancreas of carp. Further investigation showed that ROS levels significantly increased on days 7, 14, and 42. Moreover, the activities of antioxidant enzymes SOD, GSH, CAT, and GST increased significantly from 1 to 7 days, and the transcription levels of antioxidant enzymes CAT, Cu-Zn SOD, Mn-SOD, GST, and GPX, and antioxidant pathway genes Keap1, Nrf2, and HO-1 changed significantly at multiple time-points during the 42 days. The results of apoptosis pathway genes showed that the mitochondrial pathway genes Bax, Casp3, and Casp9 were significantly upregulated and Bcl2 was significantly downregulated, while the transcription levels of FADD and PERK were significantly enhanced. These results indicate that BDE-47 induced oxidative damage in hepatopancreas, then it promoted cell apoptosis mainly through the mitochondrial pathway. This study provides a foundation for analyzing the mechanism of hepatotoxicity induced by BDE-47 on fish.

Chromoproduct approach to achieve environmentally sound management of e-waste plastics: Colombian project case.

Research to prevent releases of brominated flame retardants listed as persistent organic pollutants by the Stockholm Convention (POP-BFRs) was conducted through an international cooperation project in Colombia. Six waste electrical and electronic equipment (WEEE) management facilities implemented: 1) sorting e-waste by product type and color (black, white, and other; henceforth called chromoproducts), 2) sampling test products and their plastic fraction (called sets, separated by polymer type), 3) monitoring mass, bromine and antimony contents by hand-held X-ray fluorescence (XRF) and POP-BFRs such as polybrominated diphenyl ethers (PBDEs) by gas chromatography and mass spectrometry (GC-MS), and 4) differentiated treatment according to categories that used the Restriction of Hazardous Substances in Electrical and Electronic Equipment Directive (RoHS) hazardousness threshold of 1000 mg ∑PBDEs/kg. This scheme led to the proposal of a methodology for WEEE management called the "chromoproduct approach". 994,230 products were managed and grouped into 222 chromoproducts, from which 77 were analyzed: 50 below RoHS hazardousness (BRH), 16 above RoHS hazardousness (ARH), and 11 unknown RoHS hazardousness (URH). XRF indicators using bromine and antimony contents could rule out pollution in BRH chromoproducts; however, categorization still required GC-MS. One ARH plastics sample had 3620 mg ∑PBDEs/kg, while no POP-BFRs were found in the BRH plastics sample. The implementation of the chromoproduct approach traced 153.6 tonnes of ARH plastics. BRH plastics composition was estimated and used in a pilot-scale closed-loop economic activity. The chromoproduct approach seems promising for avoiding POP-BFR releases and promoting the upcycling of recyclable e-waste plastics.

Bioaccumulation and Trophodynamics of Novel Brominated Flame Retardants (NBFRs) in Marine Food Webs from the Arctic and Antarctic Regions.

The pervasive contamination of novel brominated flame retardants (NBFRs) in remote polar ecosystems has attracted great attention in recent research. However, understanding regarding the trophic transfer behavior of NBFRs in the Arctic and Antarctic marine food webs is limited. In this study, we examined the occurrence and trophodynamics of NBFRs in polar benthic marine sediment and food webs collected from areas around the Chinese Arctic Yellow River Station (n = 57) and Antarctic Great Wall Station (n = 94). ∑7NBFR concentrations were in the range of 1.27-7.47 ng/g lipid weight (lw) and 0.09-1.56 ng/g lw in the Arctic and Antarctic marine biota, respectively, among which decabromodiphenyl ethane (DBDPE) was the predominant compound in all sample types. The biota-sediment bioaccumulation factors (g total organic carbon/g lipid) of NBFRs in the Arctic (0.85-3.40) were 4-fold higher than those in the Antarctica (0.13-0.61). Trophic magnification factors (TMFs) and their 95% confidence interval (95% CI) of individual NBFRs ranged from 0.43 (95% CI: 0.32, 0.60) to 1.32 (0.92, 1.89) and from 0.34 (0.24, 0.49) to 0.92 (0.56, 1.51) in the Arctic and Antarctic marine food webs, respectively. The TMFs of most congeners were significantly lower than 1, indicating a trophic dilution potential. This is one of the very few investigations on the trophic transfer of NBFRs in remote Arctic and Antarctic marine ecosystems, which provides a basis for exploring the ecological risks of NBFRs in polar regions.

Organohalogen compounds in a hotspot for chemical pollution: Assessment in free-ranging Atlantic spotted dolphins (Stenella frontalis).

The assessment of chemical pollution in free-ranging living mammals is viable using remote biopsies and portrays a comprehensive scenario of environmental health. The Southwestern Atlantic Ocean holds incredible biodiversity, but it is under the constant and invisible threat of persistent organic pollutants (POPs) of anthropogenic origin, such as pesticides, brominated flame retardants, and industrial-use compounds (e.g., PCBs). Thus, this study aimed to assess the bioaccumulation of POPs (PCBs, DDTs, HCB, mirex and PBDEs) and natural organobromine compounds (MeO-BDEs) using gas-chromatography coupled to mass spectrometry in biopsy samples of Atlantic spotted dolphins (Stenella frontalis, n = 20) that inhabit and forage both inside and in adjacent areas to degraded (Guanabara Bay) and conserved (Ilha Grande Bay) coastal bays in the Southeastern Brazil. Among the studied compounds, PCBs were predominant in the contamination profile with median concentration of 97.0 µg.g-1 lipid weight (lw), followed by the sum of the p,p' isomers of DDT, DDD, and DDE of 11.0 µg.g-1 lw, the brominated flame retardants PBDEs of 1.6 µg.g-1 lw, and the other organochlorine pesticides mirex of 0.78 µg.g-1 lw, and HCB of 0.049 µg.g-1 lw. The MeO-BDEs were detected with a median concentration of 22.8 µg.g-1 lw. 85 % of the Atlantic spotted dolphins analyzed in this study presented PCB concentration that exceeded even the less conservative threshold limits for adverse health effects (41 µg.g-1 lw). This study shows that despite the conservation status of preserved bays, cetacean species foraging in these locations are still under increased threat. Hence chemical pollution demands local and global efforts to be mitigated.

The impact of brominated flame retardants (BFRs) on pulmonary function in US adults: a cross-sectional study based on NHANES (2007-2012).

Brominated flame retardants (BFRs) are a group of chemicals widely used in various applications to prevent or slow down the spread of fire. However, they have adverse effects on human health. There is a relative scarcity of population-based studies regarding BFRs, particularly their impact on the respiratory system. This study aimed to investigate the influence of BFRs on pulmonary function using data from the National Health and Nutrition Examination Survey. The study found that elevated serum concentrations of certain BFRs were associated with pulmonary ventilatory dysfunction. Adjusted analyses revealed positive correlations between PBDE47, PBDE183, and PBDE209 concentrations and ventilatory dysfunction. The analysis of mixed BFRs showed a positive relationship with pulmonary ventilation dysfunction, with PBDE47 making the most significant contribution. Our study demonstrates that both individual and combined BFRs exposure can lead to impaired pulmonary ventilation function. These findings provide evidence of the adverse effects of BFRs on lung function, emphasizing the importance of further investigating the potential health consequences of these compounds. Further large-scale longitudinal studies are needed to investigate this relationship in the future.

Dynamics of leaching of POPs and additives from plastic in a Procellariiform gastric model: Diet- and polymer-dependent effects and implications for long-term exposure.

Procellariiform seabirds are known to have high rates of plastic ingestion. We investigated the bioaccessibility of plastic-associated chemicals [plastic additives and sorbed persistent organic pollutants (POPs)] leached from plastic over time using an in vitro Procellariiform gastric model. High-density polyethylene (HDPE) and polyvinyl chloride (PVC), commonly ingested by Procellariiform seabirds, were manufactured with one additive [decabrominated diphenyl ether (PBDE-209) or bisphenol S (BPS)]. HDPE and PVC added with PBDE-209 were additionally incubated in salt water with 2,4,4'-trichloro-1,1'-biphenyl (PCB-28) and 2,2',3,4,4',5'-hexachlorobiphenyl (PCB-138) to simulate sorption of POPs on plastic in the marine environment. Our results indicate that the type of plastic (nature of polymer and additive), presence of food (i.e., lipids and proteins) and gastric secretions (i.e., pepsin) influence the leaching of chemicals in a seabird. In addition, 100% of the sorbed POPs were leached from the plastic within 100 hours, while only 2-5% of the additives were leached from the matrix within 100 hours, suggesting that the remaining 95% of the additives could continue to be leached. Overall, our study illustrates how plastic type, diet and plastic retention time can influence a Procellariform's exposure risk to plastic-associated chemicals.

Selected legacy and emerging organic contaminants in sediments of China's Yangtze - the world's third longest river: Response to anthropogenic activities.

To explore contaminant concerns as a result of anthropogenic disturbance of the river system, this study provided the first extensive investigation of the contamination profiles, possible driving factors, and ecological risks of 40 target compounds including pharmaceuticals and personal care products (PPCPs), neonicotinoid pesticides (NNIs), polybrominated diphenyl ethers (PBDEs), and polychlorinated biphenyls (PCBs) in sediments of the whole Yangtze River (the world's third longest river). Among these target compounds, PPCPs were the dominant contaminants with a total concentration (∑15PPCPs) of 2.13-14.99 ng/g, followed by ∑7PCBs (