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Long-term PM0.1 exposure and human blood lipid metabolism: New insight from the 33-community study in China
2022
Zhang, Wangjian | Gao, Meng | Xiao, Xiang | Xu, Shu-Li | Lin, Shao | Wu, Qi-Zhen | Chen, Gong-Bo | Yang, Bo-Yi | Hu, Liwen | Zeng, Xiao-Wen | Hao, Yuantao | Dong, Guang-Hui
Ambient particles with aerodynamic diameter <0.1 μm (PM₀.₁) have been suggested to have significant health impact. However, studies on the association between long-term PM₀.₁ exposure and human blood lipid metabolism are still limited. This study was aimed to evaluate such association based on multiple lipid biomarkers and dyslipidemia indicators. We matched the 2006–2009 average PM₀.₁ concentration simulated using the neural-network model following the WRF-Chem model with the clinical and questionnaire data of 15,477 adults randomly recruited from 33 communities in Northeast China in 2009. After controlling for social demographic and behavior confounders, we assessed the association of PM₀.₁ concentration with multiple lipid biomarkers and dyslipidemia indicators using generalized linear mixed-effect models. Effect modification by various social demographic and behavior factors was examined. We found that each interquartile range increase in PM₀.₁ concentration was associated with a 5.75 (95% Confidence interval, 3.24–8.25) mg/dl and a 6.05 (2.85–9.25) mg/dl increase in the serum level of total cholesterol and LDL-C, respectively. This increment was also associated with an odds ratio of 1.25 (1.10–1.42) for overall dyslipidemias, 1.41 (1.16, 1.73) for hypercholesterolemia, and 1.90 (1.39, 2.61) for hyperbetalipoproteinemia. Additionally, we found generally greater effect estimates among the younger participants and those with lower income or with certain behaviors such as high-fat diet. The deleterious effect of long-term PM₀.₁ exposure on lipid metabolism may make it an important toxic chemical to be targeted by future preventive strategies.
Show more [+] Less [-]Assessment on the source of geochemical anomalies in the sediments of the Changjiang river (China), using a modified enrichment factor based on multivariate statistical analyses
2022
Dominech, Salvatore | Albanese, Stefano | Guarino, Annalise | Yang, Shouye
Rivers can be sinks for potential toxic elements (PTEs) inputted in their systems by both natural and anthropic processes. Many indices have been proposed to assess the contamination degree of sediments and the environmental conditions of surficial water bodies. Above all, enrichment factor (EF) is the most used tool, but also it is the most debated for its limitations. The need for a reference element and for a background/baseline composition makes the EF method dependent on the researcher's expertise, implying that its repeatability may not be granted. Starting from the awareness that geochemical processes, bringing to compositional changes in the environmental matrices, involve multiple elements rather than individual variables, we developed a modified EF (mEF) based on the use of elemental associations. Different multivariate statistical methods (i.e. Robust Principal Component Analysis and Fuzzy Clustering), in a compositional data analysis (CoDA) perspective, were used to set all the terms of the mEF. The mEF was applied to 101 sediment samples collected from a 2 m-long core, covering a sedimentation period of about 150 years (1850–2007), located in the lower Changjiang River (China). The method resulted effective in recognizing most of the signals proceeding from the main natural and anthropogenic events which affected the lower river basin in the considered timespan. The largest geochemical variations recorded fit well the flooding events occurred; besides, the effects produced on the system by the recent socio-economic development (following the end of the civil war in 1949 and the beginning of economic reforms in 1978) and the start-up of the Three Gorges Dam (the world's largest power station since 2012) were also intercepted. The proposed method represents a step forward to enhance the effectiveness of the EF in discriminating geochemical anomalies that may be significant to assess the human historical impact on the environment.
Show more [+] Less [-]Dermal uptake: An important pathway of human exposure to perfluoroalkyl substances?
2022
Ragnarsdóttir, Oddný | Abdallah, Mohamed Abou-Elwafa | Harrad, Stuart
Per- and polyfluoroalkyl substances (PFAS) have been produced and used in a broad range of products since the 1950s. This class, comprising of thousands of chemicals, have been used in many different products ranging from firefighting foam to personal care products and clothes. Even at relatively low levels of exposure, PFAS have been linked to various health effects in humans such as lower birth weight, increased serum cholesterol levels, and reduced antibody response to vaccination. Human biomonitoring data demonstrates ubiquitous exposure to PFAS across all age groups. This has been attributed to PFAS-contaminated water and dietary intake, as well as inadvertent ingestion of indoor dust for adults and toddlers. In utero exposure and breast milk have been indicated as important exposure pathways for foetuses and nursing infants. More recently, PFAS have been identified in a wide range of products, many of which come in contact with skin (e.g., cosmetics and fabrics). Despite this, few studies have evaluated dermal uptake as a possible route for human exposure and little is known about the dermal absorption potential of different PFAS. This article critically investigates the current state-of-knowledge on human exposure to PFAS, highlighting the lack of dermal exposure data. Additionally, the different approaches for dermal uptake assessment studies are discussed and the available literature on human dermal absorption of PFAS is critically reviewed and compared to other halogenated contaminants, e.g., brominated flame retardants and its implications for dermal exposure to PFAS. Finally, the urgent need for dermal permeation and uptake studies for a wide range of PFAS and their precursors is highlighted and recommendations for future research to advance the current understanding of human dermal exposure to PFAS are discussed.
Show more [+] Less [-]Phthalates released from microplastics inhibit microbial metabolic activity and induce different effects on intestinal luminal and mucosal microbiota
2022
Yan, Zehua | Zhang, Shenghu | Zhao, Yonggang | Yu, Wenyi | Zhao, Yanping | Zhang, Yan
The intestine is not only the main accumulation organ of microplastics (MPs), but also the intestinal environment is very conductive to the release of additives in MPs. However, the kinetics of release process, influence factors, and the related effects on gut microbiota remain largely unknown. In this study, a mucosal-simulator of the human intestinal microbial ecosystem (M-SHIME) was used to investigate the influence of gut microbiota on the release of phthalates (PAEs) from MPs and the effects of MPs on the intestinal luminal microbiota and mucosal microbiota. We found that di-(2-ethylhexyl) phthalate (DEHP), di-n-butyl phthalate (DBP), and dimethyl phthalate (DMP) were the dominant PAEs released in the gut. Gut microbiota accelerated the release of PAEs, with the time to reach the maximum release was shortened from 7 days to 2 days. Moreover, MPs induced differential effects on luminal microbiota and mucosal microbiota. Compared with mucosal microbiota, the luminal microbiota was more susceptible to the leaching of PAEs from MPs, as evidenced by more microbiota alterations. MPs also inhibited the metabolic activity of intestinal flora based on the reduced production of short chain fatty acids (SCFA). These effects were mainly contributed by the release of PAEs. Acidaminococcus and Morganella were simultaneously correlated to the release of PAEs and the inhibition of metabolic activity of intestinal microbiota and can be used as indicators for the intestinal exposure of MPs and additives.
Show more [+] Less [-]Wild fish and seafood species in the western Mediterranean Sea with low safe mercury concentrations
2022
Capodiferro, Marco | Marco, Esther | Grimalt, Joan O.
A total of 1345 specimens belonging to 58 different species of wild fish and seafood from the western Mediterranean Sea were analyzed to assess total mercury levels and to estimate which species meet the EU recommendations for human consumption (0.5 μg g⁻¹ ww) in all cases. All fish species were caught off the Mediterranean coasts and intended for human consumption. All specimens were collected from local markets located in Spain, Italy and France that sell fish caught by local fishermen (Eivissa, Menorca, Mallorca, Alacant, L'Ampolla, Ametlla de Mar, Marseille, Genoa, Civitavecchia, Alghero) at different time periods. Mercury concentrations were measured by thermal decomposition-gold amalgamator-atomic absorption spectrometry. Only thirteen species were found that did not exceed 0.5 μg g⁻¹ ww in any specimen analyzed. These safe species were sardines (Sardina pilchardus), anchovies (Engraulis encrasicolus), blue whiting (Micromesistius poutassou), picarel (Spicara smaris), blackspot seabream (Pagellus bogaraveo), gilthead seabream (Sparus aurata), pearly razorfish (Xyrichtys novacula), surmullet (Mullus surmuletus), painted comber (Serranus scriba), brown meagre (Sciaena umbra), salema (Sarpa salpa), common dolphinfish (Coryphaena hippurus) and squid (Loligo vulgaris). These species occupy different trophic levels, have different lengths and average weights, but show a low mercury concentration than others living in the same environments. Potential human consumption of these species as sole source of fish would imply estimated weekly intakes representing between 49% and 70% of the recommended provisional tolerable weekly intake of methylmercury in the worst case. Health authorities should pay specific attention to species that do not meet EU thresholds and make appropriate precautionary health recommendations, especially for pregnant women and children.
Show more [+] Less [-]Effects of river-lake disconnection and eutrophication on freshwater mollusc assemblages in floodplain lakes: Loss of congeneric species leads to changes in both assemblage composition and taxonomic relatedness
2022
Jiang, Xiaoming | Li, Zhengfei | Shu, Fengyue | Chen, Jing
River floodplain ecosystems host one of the highest freshwater molluscan biodiversity on Earth. However, multiple human disturbances, such as loss of hydrological connectivity and deterioration of water quality, are seriously threatening most floodplain lakes throughout the world. Given the high imperilment rate of freshwater molluscs but the scarcity of studies examining the anthropogenic effects on this fauna, we test the response of mollusc assemblages to river-lake disconnection and eutrophication in 30 lakes in the Yangtze River floodplain, China. The species richness of entire Mollusca, Gastropoda and Bivalvia and 6 dominant families were all much lower at disconnected lakes than that in connected lakes, and decreased with increasing water eutrophication. The assemblage structure differed significantly among four lake groups for datasets based on entire Mollusca, Gastropoda and Bivalvia, indicating the serious impacts of hydrological disconnection and eutrophication. Moreover, the connected lakes showed significantly lower values of average taxonomic distinctness (Δ⁺) but higher values of variation in taxonomic distinctness (Λ⁺) than disconnected lakes. Such variations were triggered by the extirpation of congeneric and endemic species (mainly from families Unionidae and Viviparidae), which giving a waring of the loss of mollusc endemism in this region. In general, the present study showed that river-lake disconnection and deterioration of water quality resulted in serious biodiversity declines of both gastropods and bivalves in the Yangtze River floodplain lakes. A systematic approach including restoration of river-lake connectivity and habitats and improvement of water quality should be implemented in the conservation planning in this large river floodplain.
Show more [+] Less [-]Urban fine particulate matter causes cardiac hypertrophy through calcium-mediated mitochondrial bioenergetics dysfunction in mice hearts and human cardiomyocytes
2022
Zou, Lingyue | Li, Binjing | Xiong, Lilin | Wang, Yan | Xie, Wenjing | Huang, Xiaoquan | Liang, Ying | Wei, Tingting | Liu, Na | Chang, Xiaoru | Bai, Changcun | Wu, Tianshu | Xue, Yuying | Zhang, Ting | Tang, Meng
In recent years, the cardiovascular toxicity of urban fine particulate matter (PM₂.₅) has sparked significant alarm. Mitochondria produce 90% of ATP and make up 30% of the volume of cardiomyocytes. Thus knowledge of myocardial mitochondrial dysfunction due to PM₂.₅ exposure is essential for further cardiotoxic effects. Here, the mechanism of PM₂.₅-induced cardiac hypertrophy through calcium overload and mitochondrial dysfunction was investigated in vivo and in vitro. Male and female BALB/c mice were given 1.28, 5.5, and 11 mg PM₂.₅/kg bodyweight weekly through oropharyngeal inhalation for four weeks and were assigned to low, medium, and high dose groups, respectively. PM₂.₅-induced myocardial edema and cardiac hypertrophy were detected in the high-dose group. Mitochondria were scattered and ruptured with abnormal ultrastructural morphology. In vitro experiments on human cardiomyocyte AC16 showed that exposure to PM₂.₅ for 24 h caused opened mitochondrial permeability transition pore --leading to excessive calcium production, decreased mitochondrial membrane potential, weakened mitochondrial respiratory metabolism capacity, and decreased ATP production. Nevertheless, the administration of calcium chelator ameliorated the mitochondrial damage in the PM₂.₅-treated group. Our in vivo and in vitro results confirmed that calcium overload under PM₂.₅ exposure triggered mTOR/AKT/GSK-3β activation, leading to mitochondrial bioenergetics dysfunction and cardiac hypertrophy.
Show more [+] Less [-]Health impacts of artificial turf: Toxicity studies, challenges, and future directions
2022
Murphy, Maire | Warner, Genoa R.
Many communities around the country are undergoing contentious battles over the installation of artificial turf. Opponents are concerned about exposure to hazardous chemicals leaching from the crumb rubber cushioning fill made of recycled tires, the plastic carpet, and other synthetic components. Numerous studies have shown that chemicals identified in artificial turf, including polycyclic aromatic hydrocarbons (PAHs), phthalates, and per- and polyfluoroalkyl substances (PFAS), are known carcinogens, neurotoxicants, mutagens, and endocrine disruptors. However, few studies have looked directly at health outcomes of exposure to these chemicals in the context of artificial turf. Ecotoxicology studies in invertebrates exposed to crumb rubber have identified risks to organisms whose habitats have been contaminated by artificial turf. Chicken eggs injected with crumb rubber leachate also showed impaired development and endocrine disruption. The only human epidemiology studies conducted related to artificial turf have been highly limited in design, focusing on cancer incidence. In addition, government agencies have begun their own risk assessment studies to aid community decisions. Additional studies in in vitro and in vivo translational models, ecotoxicological systems, and human epidemiology are strongly needed to consider exposure from both field use and runoff, components other than crumb rubber, sensitive windows of development, and additional physiological endpoints. Identification of potential health effects from exposures due to spending time at artificial turf fields and adjacent environments that may be contaminated by runoff will aid in risk assessment and community decision making on the use of artificial turf.
Show more [+] Less [-]Comprehensive investigation of persistent and mobile chemicals and per- and polyfluoroalkyl substances in urine of flemish adolescents using a suspect screening approach
2022
Kim, Da-Hye | Jeong, Yunsun | Belova, Lidia | Roggeman, Maarten | Fernández, Sandra F. | Poma, Giulia | Rémy, Sylvie | Verheyen, Veerle J. | Schoeters, Greet | van Nuijs, Alexander L.N. | Covaci, Adrian
Persistent and mobile chemicals (PMs) and per- and polyfluoroalkyl substances (PFAS) are groups of chemicals that have received recent global attention due to their potential health effects on the environment and humans. In this study, exposure to a broad range of PMs and PFAS was investigated in Flemish adolescents’ urine samples (n = 83) using a suspect screening approach. For this purpose, three sample preparation methods were evaluated, and a basic liquid-liquid extraction was optimized for urine analysis based on the extraction efficiency of PMs (53–80%) and PFAS (>70%). In total, 9 PMs were identified in urine samples at confidence levels (CL) 1–3 and, among them, acetaminophen, 4-aminophenol, 2,2,6,6-tetramethyl-4-piperidone, trifluoroacetic acid (TFAA), sulisobenzone, ethyl sulfate, and 1,2-benzisothiazol-3(2H)-one 1,1-dioxide were confirmed at CL 1 and 2. In addition, the detection and identification of 2,2,6,6-tetramethyl-4-piperidone, 4-aminophenol, TFAA, and m-(2,3-epoxypropoxy)-N,N-bis(2,3-epoxypropyl) aniline (CL 3), has been reported for the first time in human urine in this study. For PFAS, only 2 compounds were identified at CL 4, implying that urine is not a suitable matrix for suspect screening of such compounds. A significant difference between sexes was observed in the detection rate of identified PMs, in particular for acetaminophen, 4-aminophenol, and sulisobenzone. The findings of this study can be used in future human biomonitoring programs, such as by including the newly identified compounds in quantitative methods or monitoring in other human matrices (e.g., serum).
Show more [+] Less [-]Systematic review of human biomonitoring studies of ethylenethiourea, a urinary biomarker for exposure to dithiocarbamate fungicides
2022
Stadler, Katrina | Li, Xueshu | Liu, Buyun | Bao, Wei | Wang, Kai | Lehmler, Hans-Joachim
Toxicological and epidemiological studies implicate exposure to dithiocarbamate (DTC) fungicides in adverse health outcomes. However, there is limited information about human exposure to these chemicals. This systematic review determined to which extent human populations worldwide, including children, pregnant women, and adults, are exposed environmentally or occupationally to DTC pesticides and how these exposures compare to the NHANES 2003–2008 population, using urinary ETU data as an outcome measure. PubMed, Embase, and SciFinder were searched using the keywords “ethylenethiourea” or CAS No.: 96-45-7, and urine or urinary. Duplicates and irrelevant studies were removed from the search results based on predetermined exclusion criteria. This screening process identified 17 relevant papers. One additional paper was found independent of this search. Data from studies were extracted using a pre-established data collection form. Ten, two, and five manuscripts reported urinary levels in environmentally exposed adults, children, and pregnant women, respectively. Median ETU levels ranged from 0.15 to 4.7 μg/g creatinine in adults (1994–2017), 0.24–0.83 μg/g creatinine in children (2011), and 2.6–5.24 ng/ml in pregnant women (2011). Eight studies reported urinary ETU levels in mostly agriculturally exposed populations, with median ETU levels ranging from 0.42 to 49.6 μg/g creatinine (1999–2011). With one exception, all studies were conducted between 1994 and 2011. ETU levels in the NHANES 2003–2008 population appeared to be generally lower than most studies identified in this review. This finding suggests that, historically, DTC fungicide exposures in the general population of high-income countries, such as the US, were low, whereas agricultural populations may have experienced higher exposure. Unfortunately, more recent exposure data are missing, especially in countries where DTC pesticides are not being phased out.
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