Exposure to polybrominated diphenyl ethers (PBDEs) in American and Canadian workers: Biomonitoring data from two national surveys

Bioaccumulation of polystyrene nanoplastics and BDE-209 induced oxidative stress, photosynthesis and growth impairments in floating fern Salvinia natans

Aquatic ecosystems are facing increasing exposure to pollutants, posing potential threats to the stability and wellness of aquatic species. This study focused on evaluating the impacts of single and combined exposure to 80 nm polystyrene nanoplastics (PS-NPs, 0.1, 1, 10, 20 mg/L) and decabromodiphenyl ether (BDE-209, 300 ng/L) for 14 days on the bioaccumulation, growth, photosynthesis and oxidative stress in the free-floating fern Salvinia natans. PS-NPs primarily accumulated in the epidermis and trichomes of S. natans. Meanwhile, the levels of superoxide dismutase (SOD) and malondialdehyde (MDA) were significantly increased, while those for peroxidase (POD), catalase (CAT), total antioxidant capacity (T-AOC), and relative growth rate (RGR) decreased. Furthermore, the chlorophyll contents in submerged leaves were decreased, while those in floating leaves were increased at PS-NPs concentrations of 0.1 and 1 mg/L. However, the chlorophyll contents in both submerged and floating leaves displayed a decreasing trend with increasing concentrations of PS-NPs. Under the co-exposure of PS-NPs and BDE-209, the contents of MDA were significantly elevated, whereas CAT, POD, SOD, T-AOC and RGR were significantly decreased (p < 0.05). Our results revealed that, compared to single exposure, more pronounced ecotoxic effects are observed in S. natans under co-exposure to PS-NPs and BDE-209. These findings offer valuable perspectives into the possible environmental risks of BDE-209 and PS-NPs in freshwater ecosystems, contributing to the development of effective management strategies for protecting aquatic organisms and ecosystems. This research highlights the urgent need to understand the toxic effects of emerging contaminants on different aquatic organisms, emphasizing the importance of protecting and preserving aquatic ecosystems.

Assessment of the effects of solvents on lung function among paint industry workers in Mauritius

The study aimed to determine the respiratory effects of solvents among workers in the Mauritius paint industry. A total of 388 participants were selected using simple random sampling, and were subjected to a questionnaire for data collection. Lung function test was performed using a spirometer. Multiple regression was used to analyze the relationship between hours of exposure to solvents, while adjusting for socio-demographic factors. Independent t-test was also used to identify any difference between the means of lung function tests and the two exposed groups. Male participants were found less likely exposed to solvents compared to females (AOR, 3.39, CI 1.97-5.81). Those with secondary and lower secondary education, and worked for ≤12 hours per week, had an increased likelihood of being exposed to solvents (AOR 2.95, CI 1.20-7.28) (AOR 2.48, CI 1.19-5.16). Participants who were aware of occupational hazards (AOR 0.15, CI (0.05-0.46), and have used PPE (AOR 0.14, CI 0.08-0.25) were less likely to be less exposed to solvents. This study highlights the adverse effects of workplace exposures on respiratory health among paint factory workers. .

Lysmeral Exposure in Children and Adolescences Participating in the German Environmental Survey (2012-2015): Integrating Sex/Gender into Analysis

Comprehensive consideration of the biological and social diversities of sex and gender as well as their interdependencies is mostly missing in human biomonitoring (HBM) studies. Using the INGER sex/gender concept as theoretical background, we analyzed differences in exposure to lysmeral, a compound commonly found as a fragrance in cosmetics, personal care, and household products, in 2294 children and adolescents in Germany using decision tree, regression, and mediation analysis. The variables "sex assigned at birth" and "age", as well as well as use of personal care products and fabric conditioner proved to have the highest explanatory value. Mediating effects of behaviour associated with societal gender expectations were observed, as the use of cosmetics correlated highly with lysmeral metabolites concentrations in girls between 6 and 17 years, with the strongest effect in adolescents between 14 and 17 years old. In the youngest age group (3-5 years) boys showed higher concentration of the metabolite tert-butylbenzoic acid (TBBA) compared to girls of the same age but only if TBBA urine concentrations were normalized on creatinine. Our study offers the first retrospective sex/gender assessment of HBM data. It demonstrates the possibilities to rethink and broaden sex/gender analysis in existing HBM-studies and highlights the need for inclusion of new sex/gender concepts in the design of new studies.

Persistent organic pollutants and β-cell toxicity: a comprehensive review

Persistent organic pollutants (POPs) are a diverse family of contaminants that show widespread global dispersion and bioaccumulation. Humans are continuously exposed to POPs through diet, air particles, and household and commercial products; POPs are consistently detected in human tissues, including the pancreas. Epidemiological studies show a modest but consistent correlation between exposure to POPs and increased diabetes risk. The goal of this review is to provide an overview of epidemiological evidence and an in-depth evaluation of the in vivo and in vitro evidence that POPs cause β-cell toxicity. We review evidence for six classes of POPs: dioxins, polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), organophosphate pesticides (OPPs), flame retardants, and per- and polyfluoroalkyl substances (PFAS). The available data provide convincing evidence implicating POPs as a contributing factor driving impaired glucose homeostasis, β-cell dysfunction, and altered metabolic and oxidative stress pathways in islets. These findings support epidemiological data showing that POPs increase diabetes risk and emphasize the need to consider the endocrine pancreas in toxicity assessments. Our review also highlights significant gaps in the literature assessing islet-specific endpoints after both in vivo and in vitro POP exposure. In addition, most rodent studies do not consider the impact of biological sex or secondary metabolic stressors in mediating the effects of POPs on glucose homeostasis and β-cell function. We discuss key gaps and limitations that should be assessed in future studies.

Sex and Gender Differences in Occupational Hazard Exposures: a Scoping Review of the Recent Literature

PURPOSE OF REVIEW

Comparative research on sex and/or gender differences in occupational hazard exposures is necessary for effective work injury and illness prevention strategies. This scoping review summarizes the peer-reviewed literature from 2009 to 2019 on exposure differences to occupational hazards between men and women, across occupations, and within the same occupation.

RECENT FINDINGS

Fifty-eight studies retrieved from eight databases met our inclusion criteria. Of these, 30 studies were found on physical hazards, 38 studies on psychological/psychosocial hazards, 5 studies on biological hazards, and 17 studies on chemical hazards. The majority of studies reported that men were exposed to noise, vibration, medical radiation, physically demanding work, solar radiation, falls, biomechanical risks, chemical hazards, and blood contamination; while women were exposed to wet work, bullying and discrimination, work stress, and biological agents. Within the same occupations, men were more likely to be exposed to physical hazards, with the exception of women in health care occupations and exposure to prolonged standing. Women compared to men in the same occupations were more likely to experience harassment, while men compared to women in the same occupations reported higher work stress. Men reported more exposure to hazardous chemicals in the same occupations as women. The review suggests that men and women have different exposures to occupational hazards and that these differences are not solely due to a gendered distribution of the labor force by occupation. Findings may inform prevention efforts seeking to reduce gender inequalities in occupational health. Future research is needed to explain the reasons for sex/gender inequality differences in exposures within the same occupation.

Polybrominated diphenyl ethers (PBDEs) in the Danjiangkou Reservoir, China: identification of priority PBDE congeners

Although the production of polybrominated diphenyl ethers (PBDEs) has been phased out over the past decade worldwide, they are still potentially hazardous to the environment due to their persistence and toxicity. This study investigated the levels of 55 PBDEs in water and sediments from the Danjiangkou Reservoir, China. The levels of PBDEs were in the range of not detected (ND)-286.67 ng/L in water and ND-236.04 ng/g in sediments. BDE209 was the predominant PBDE congener and constituted 15-50% and 44-68% of the total PBDEs in water and sediments, respectively. Commercial pentaBDE products (70-5DE, DE-71) were the dominant source of tetraBDE, pentaBDE, and hexaBDE, while commercial octaBDE (79-8DE) and decaBDE (102E and 82-0DE) products were the main sources of nonaBDE and decaBDE in water. PBDEs in sediments mainly stemmed from commercial decaBDE products and combustion sources. BDE-209 posed high ecological risks to aquatic organisms and dominated the total ecological risks of PBDEs. No cancer risks and non-cancer risks were observed for PBDEs. A ranking method based on four criteria, i.e., detection frequency, concentration, ecological risk, and health risks, was proposed, and 17 PBDEs were identified as high priority PBDEs for future monitoring and management in the Danjiangkou Reservoir.

Prenatal exposure to polybrominated diphenyl ethers (PBDEs) and cognitive ability in early childhood

BACKGROUND

Prenatal exposure to polybrominated diphenyl ethers (PBDEs) has been associated with adverse neurodevelopmental outcomes in children, but evidence remains mixed regarding sex differences in this association.

OBJECTIVE

To examine the prospective association between prenatal PBDE exposure and cognitive ability in young children, as well as potential sex differences.

METHODS

The study was conducted in a multi-site Canadian pregnancy cohort recruited in 2008-11. PBDEs were measured in maternal plasma samples collected early in pregnancy. Cognitive ability was assessed using the Wechsler Preschool and Primary Scale of Intelligence (WPPSI-III) in children at age 3 years (mean = 3.4). Multiple linear regression was used to analyze the association between maternal PBDE plasma concentrations (lipid-standardized and log10-transformed) and Verbal, Performance, and Full Scale IQ scores on the whole sample and stratified by sex, adjusting for confounders.

RESULTS

The sample was composed of 592 children (291 boys and 301 girls). A tenfold increase in maternal blood PBDE concentration (sum of BDE-47, -99, -100, and -153) was associated with lower Full Scale scores in boys (-3.4 points; 95% CI: -7.0, 0.1), after adjusting for confounders. BDE-47 was the congener with the highest concentrations in maternal blood and a tenfold increase in exposure was associated with significantly lower Full Scale IQ scores in boys (-4.4 points; 95% CI: -7.9, -0.9), after adjusting for confounders. Verbal and Performance IQ scores were similarly associated with PBDE exposure. Maternal blood PBDE concentrations were not associated with IQ scores in girls.

CONCLUSIONS

Prenatal exposure to background levels of PBDEs, especially BDE-47, was associated with lower IQ scores in boys, but not in girls. Our results support that exposure to PBDEs during early development may be sex-dependent and detrimental to a child's neurodevelopmental trajectory.

Debromination of polybrominated diphenyl ethers (PBDEs) by palladized zerovalent zinc particles: Influence factors, pathways and mechanism

We synthesized a novel material, namely palladized zero-valent zinc (Pd/ZVZ), and investigated its efficiency for the degradation of polybrominated diphenyl ethers (PBDEs). The plated Pd significantly enhances the degradation rate of PBDEs by ZVZ at the optimum loading of 1% by weight. In the Pd/ZVZ system, very few lower BDEs were accumulated during the degradation of 2,2',4,4'- tetrabromodiphenyl ether (BDE-47) and the final product is diphenyl ether, whereas the ZVZ system only debrominates BDE-47 to di-BDE and further debromination becomes very difficult. The degradation rates of BDEs by ZVZ greatly decreased with decreased bromination level, while in Pd/ZVZ system, the degradation rates of PBDEs did not show a significant difference. These indicate different mechanisms. This was confirmed by investigating the debromination pathways of the PBDEs in both systems. We determined that a H-transfer was the dominant mechanism in the Pd/ZVZ system. In addition, the reactivity of Pd/ZVZ to BDE-47 is pH-independent, which has a great advantage for various applications over ZVZ alone. Our study provides a new approach for the remediation of the PBDEs pollution.

Dried blood spots for the identification of bio-accumulating organic compounds: current challenges and future perspectives

The exposome is a concept that underlines the critical relationship between health and environmental exposures, including environmental toxicants. Currently, most environmental exposures that contribute to the exposome have not been characterized. Dried-blood spots (DBS) offer a cost-effective, reliable approach to characterize the blood exposome, which consists of diverse endogenous and exogenous chemicals, including persistent and bioaccumulating organic compounds. Current challenges involve prioritizing the identification by state-of-the-art mass spectrometry of likely up to tens of thousands of compounds present in blood; characterizing substances that represent a mixture of myriad constituent compounds; and detecting trace level contaminants, especially in quantity-limited matrices like DBS. This contribution reviews recent trends in DBS analysis of chemical pollutants and highlights the need for continued research in analytical chemistry to advance the field of exposomics.

Levels and congener profiles of halogenated persistent organic pollutants in human serum and semen at an e-waste area in South China

Typical halogenated persistent organic pollutants (Hal-POPs), including polybrominated diphenyl ethers (PBDEs), polybrominated biphenyls (PBBs), polychlorinated biphenyls (PCBs), and dichlorodiphenyltrichloroethane (DDT), are a group of ubiquitous organic pollutants with an endocrine disrupting effect. This study evaluated the accumulation and congener profiles of Hal-POPs in the bodies of men who live/work in areas of South China where electronic wastes are collected and managed, especially in their semen samples. The results show that the detection frequency and serum concentrations of Hal-POP congeners within the high-exposure group (HEG) were higher than those of the low-exposure group (LEG). Furthermore, an identical trend was observed for the seminal plasma concentrations of Hal-POPs. The distribution characteristics, such as their mean, median, and discrete values, of PBDE congeners in serum and semen samples from the same subjects were consistent with each other. However, the distribution characteristics of PCB congeners in serum samples were different from those in semen samples. BDE153 was one of the most abundant congeners found in the serum and semen samples; hence, it can be identified as an indicator PBDE congener. Further research is needed to explore the mechanism of Hal-POPs distribution in human semen and serum samples.

Assessment of Occupational Exposure to Organic Flame Retardants: A Systematic Review

BACKGROUND

Flame retardants (FRs) are widespread in common goods, and workers in some industries can be exposed to high concentrations. Numerous studies describe occupational exposure to FRs, but the diversity of methods and of reported results renders their interpretation difficult for researchers, occupational hygienists, and decision makers.

OBJECTIVES

The objectives of this paper are to compile and summarize the scientific knowledge on occupational exposure to FRs as well as to identify research gaps and to formulate recommendations.

METHODS

Five databases were consulted for this systematic literature review (Embase, Medline [Pubmed], Global health, Web of Science, and Google Scholar), with terms related to occupational exposure and to FRs. Selected studies report quantitative measurements of exposure to organic FRs in a workplace, either in air, dust, or in workers' biological fluids. The Preferred Reporting Items for Systematic reviews and Meta-Analyses statement guidelines were followed.

RESULTS

The search yielded 1540 published articles, of which 58 were retained. The most frequently sampled FRs were polybrominated diphenyl ethers and novel brominated FRs. Offices and electronic waste recycling facilities were the most studied occupational settings, and the highest reported exposures were found in the latter, as well as in manufacturing of printed circuit boards, in aircrafts, and in firefighters. There were recurrent methodological issues, such as unstandardized and ill-described air and dust sampling, as well as deficient statistical analyses.

CONCLUSIONS

This review offers several recommendations. Workplaces such as electronic waste recycling or manufacturing of electronics as well as firefighters and aircraft personnel should be granted more attention from researchers and industrial hygienists. Methodical and standardized occupational exposure assessment approaches should be employed, and data analysis and reporting should be more systematic. Finally, more research is needed on newer chemical classes of FRs, on occupational exposure pathways, and on airborne FR particle distribution.

Temporal trends in serum polybrominated diphenyl ether concentrations in the Australian population, 2002-2013

In Australia, systematic biomonitoring of persistent organic pollutants (POPs) in pooled serum samples stratified by age and sex has occurred every two years between 2002/03 and 2012/13. Multiple regression modeling on log10-transformed serum pool concentrations of BDEs 47, 99, 100 and 153 and on the sum of these (Σ₄PBDE) was conducted to examine trends by sex and time since baseline, stratified by age group. Temporal trends were age- and congener-specific, with the largest changes per year of observation in the 0-4 year old group, with β (SE) = -0.098 (0.013) for log₁₀BDE47; -0.119 (0.012) for log₁₀BDE99; -0.084 (0.014) for log₁₀BDE100, and -0.053 (0.013) for log₁₀BDE153, all p < 0.001. Adults over age 16 showed much smaller decreasing temporal trends for BDE47 and BDE99, no significant changes in BDE100, and, for the oldest age groups, slight increases in BDE153. As a result, Σ₄PBDE concentrations were stable over the entire time period in adults older than 16. Concentrations of each BDE in pools from females aged 31-60 were significantly lower compared to males. Relative proportions of BDE47 declined, while BDE153 accounted for a greater share of Σ₄PBDE over time. Whereas previously we saw a large elevation in the youngest age groups compared to older children and adults, this is no longer the case. This may be due to a decline in infant and toddler exposures in the indoor environment as use of PBDEs in consumer products has been phased out, suggesting temporal changes in the relative sources of exposure for young children in Australia.