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Background: Polycyclic aromatic hydrocarbons (PAHs) and metals were associated with decreased lung function, but co-exposure effects and underlying mechanism remained unknown. Methods: Among 1,123 adults from National Health and Nutrition Examination Survey 2011–2012, 10 urinary PAHs, 11 urinary metals, and peripheral white blood cell (WBC) count were determined, and 5 lung function indices were measured. Least absolute shrinkage and selection operator, Bayesian kernel machine regression, and quantile-based g-computation were used to estimate co-exposure effects on lung function. Mediation analysis was used to explore mediating role of WBC. Results: These models demonstrated that PAHs and metals were significantly associated with lung function impairment. Bayesian kernel machine regression models showed that comparing to all chemicals fixed at median level, forced expiratory volume in 1 s (FEV1)/forced vital capacity, peak expiratory flow, and forced expiratory flow between 25 and 75% decreased by 1.31% (95% CI: 0.72%, 1.91%), 231.62 (43.45, 419.78) mL/s, and 131.64 (37.54, 225.74) mL/s respectively, when all chemicals were at 75th percentile. In the quantile-based g-computation, each quartile increase in mixture was associated with 104.35 (95% CI: 40.67, 168.02) mL, 1.16% (2.11%, 22.40%), 294.90 (78.37, 511.43) mL/s, 168.44 (41.66, 295.22) mL/s decrease in the FEV1, FEV1/forced vital capacity, peak expiratory flow, and forced expiratory flow between 25% and 75%, respectively. 2-Hydroxyphenanthrene, 3-Hydroxyfluorene, and cadmium were leading contributors to the above associations. WBC mediated 8.22%-23.90% of association between PAHs and lung function. Conclusions: Co-exposure of PAHs and metals impairs lung function, and WBC could partially mediate this relationship. Our findings elucidate co-exposure effects of environmental mixtures on respiratory health and underlying mechanisms, suggesting that focusing on highly prioritized toxicants would effectively attenuate adverse effects. [ABSTRACT FROM AUTHOR]

Currently, many countries and regions worldwide face the challenge of declining population growth due to persistently low rates of female reproduction. Since 2017, China's birth rate has hit historic lows and continued to decline, with the death rate now equaling the birth rate. Concerns have emerged regarding the potential impact of environmental contaminants on reproductive health, including pregnancy loss. Endocrine-disrupting chemicals (EDCs) like phthalate esters (PAEs), bisphenol A (BPA), triclosan (TCS), and perfluoroalkyl substances (PFASs) have raised attention due to their adverse effects on biological systems. While China's 14th Five-Year Plan (2021–2025) for national economic and social development included the treatment of emerging pollutants, including EDCs, there are currently no national appraisal standards or regulatory frameworks for EDCs and their mixtures. Addressing the risk of EDC mixtures is an urgent matter that needs consideration from China's perspective in the near future. In this Perspective, we delve into the link between EDC mixture exposure and pregnancy loss in China. Our focus areas include establishing a comprehensive national plan targeting reproductive-aged women across diverse urban and rural areas, understanding common EDC combinations in women and their surrounding environment, exploring the relationship between EDCs and pregnancy loss via epidemiology, and reconsidering the safety of EDCs, particularly in mixtures and low-dose scenarios. We envision that this study could aid in creating preventive strategies and interventions to alleviate potential risks induced by EDC exposure during pregnancy in China.

Abstract Background Polycyclic aromatic hydrocarbons (PAHs) and metals were associated with decreased lung function, but co-exposure effects and underlying mechanism remained unknown. Methods Among 1,123 adults from National Health and Nutrition Examination Survey 2011–2012, 10 urinary PAHs, 11 urinary metals, and peripheral white blood cell (WBC) count were determined, and 5 lung function indices were measured. Least absolute shrinkage and selection operator, Bayesian kernel machine regression, and quantile-based g-computation were used to estimate co-exposure effects on lung function. Mediation analysis was used to explore mediating role of WBC. Results These models demonstrated that PAHs and metals were significantly associated with lung function impairment. Bayesian kernel machine regression models showed that comparing to all chemicals fixed at median level, forced expiratory volume in 1 s (FEV1)/forced vital capacity, peak expiratory flow, and forced expiratory flow between 25 and 75% decreased by 1.31% (95% CI: 0.72%, 1.91%), 231.62 (43.45, 419.78) mL/s, and 131.64 (37.54, 225.74) mL/s respectively, when all chemicals were at 75th percentile. In the quantile-based g-computation, each quartile increase in mixture was associated with 104.35 (95% CI: 40.67, 168.02) mL, 1.16% (2.11%, 22.40%), 294.90 (78.37, 511.43) mL/s, 168.44 (41.66, 295.22) mL/s decrease in the FEV1, FEV1/forced vital capacity, peak expiratory flow, and forced expiratory flow between 25% and 75%, respectively. 2-Hydroxyphenanthrene, 3-Hydroxyfluorene, and cadmium were leading contributors to the above associations. WBC mediated 8.22%-23.90% of association between PAHs and lung function. Conclusions Co-exposure of PAHs and metals impairs lung function, and WBC could partially mediate this relationship. Our findings elucidate co-exposure effects of environmental mixtures on respiratory health and underlying mechanisms, suggesting that focusing on highly prioritized toxicants would effectively attenuate adverse effects.

Fluoride, a global environmental pollutant, is ubiquitous in aquatic environments and coexists with selenium, which can cause complex effects on exposed organisms. However, data on the interaction of fluoride and selenium remain scarce. In this study, female zebrafish (Danio rerio) were exposed to fluoride (80 mg/L sodium fluoride) and/or dietary selenomethionine (Se-Met) for 30, 60 and 90 days, the effects on the liver of zebrafish were investigated. The results indicated that an increase in fluoride burden, inhibited growth and impaired liver morphology were recorded after fluoride exposure. Furthermore, fluoride alone caused oxidative stress and inflammation in the liver, as reflected by the increase in ROS and MDA contents, the reduction of anti-oxidative enzymes, the altered immune related enzymes (ACP, AKP, LZM and MPO) and the expression of IL-6, IL-1β, TNF-α, IL-10 and TGF-β. In contrast, co-exposure to fluoride and Se-Met decreased fluoride burden and restored growth. Furthermore, dietary Se-Met alleviated oxidative stress, inflammation and impaired morphology in liver trigger by fluoride. However, dietary Se-Met alone increased the activities of SOD and CAT. These results demonstrate that the protective effect of dietary Se-Met against chronic fluoride toxicity at a certain level. [ABSTRACT FROM AUTHOR]

Background: As the global aging process accelerates, the health challenges posed by sarcopenia among middle-aged and older adults are becoming increasingly prominent. However, the available evidence on the adverse effects of air pollution on sarcopenia is limited, particularly in the Western Pacific region. This study aimed to explore relationships of multiple air pollutants with sarcopenia and related biomarkers using the nationally representative database. Methods: Totally, 6585 participants aged over 45 years were enrolled from the China Health and Retirement Longitudinal Study (CHARLS) in 2011 and 3443 of them were followed up until 2015. Air pollutants were estimated from high-resolution satellite-based spatial-temporal models. In the cross-sectional analysis, we used generalized linear regression, unconditional logistic regression analytical and restricted cubic spline (RCS) methods to assess the single-exposure and non-linear effects of multiple air pollutants on sarcopenia and related surrogate biomarkers (serum creatinine and cystatin C). Several popular mixture analysis techniques such as Bayesian kernel machine regression (BKMR), weighted quantile sum (WQS) regression, and quantile-based g-computation (Qgcomp) were further used to examinate the combined effects of multiple air pollutants. Logistic regression was used to further analyze the longitudinal association between air pollution and sarcopenia. Results: Each interquartile range increase in PM2.5, PM10 and NO2 was significantly associated with an increased risk of sarcopenia, with adjusted odds ratios (aORs) of 1.09 [95 % confidence interval (CI): 1.01, 1.20], 1.24 (95 % CI: 1.14, 1.35) and 1.18 (95 % CI: 1.08, 1.28), respectively. Our findings also showed that five air pollutants were significantly associated with the sarcopenia index. In addition, employing a mixture analysis approach, we confirmed significant combined effects of air pollution mixtures on sarcopenia risk and associated biomarkers, with PM10 and PM2.5 identified as major contributors to the combined effect. The results of the exposure-response (E-R) relationships, subgroup analysis, longitudinal analysis and sensitivity analysis all showed the unfavorable impact of air pollution on sarcopenia risk and related vulnerable populations. Conclusions: Single-exposure and co-exposure to multiple air pollutants were positively associated with sarcopenia among middle-aged and older adults in China. Our study provided new evidence that air pollution mixture was significantly associated with sarcopenia related biomarkers.

Adsorption is one of the most feasible and effective methods to alleviate the volatile organic compounds (VOCs) pollution. However, the mixture effect and mechanism for competitive adsorption of VOCs on zeolites are barely addressed. In this study, toluene, acetone, and ethyl acetate as prevalent VOCs species were removed by four potential zeolites (13X, USY, Beta, ZSM-5) in both single- and multi-component systems. The structure-property relationship between adsorbate-adsorbent pairs was revealed by X-ray diffraction, scanning electron microscopy, energy dispersive spectrometer, X-ray fluorescence, N 2 adsorption and density function theory calculation. The molecular polarity and volatility of VOCs species played key roles in adsorption and the dynamic uptakes were generally listed as follows: ethyl acetate > toluene > acetone. As for the above VOCs mixtures, 13X zeolite selectively adsorbed oxygenated VOCs rather than toluene. In contrast, USY exhibited a preference to trap toluene. Ethyl acetate could be readily enriched by ZSM-5 and Beta selectively. The possible explanations and implications are discussed based on the subtle change in electron density. The results obtained are vital for understanding the mixture effect of VOCs adsorption and may guide the selection of proper adsorbent for real applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Farmland soil organisms frequently encounter pesticide mixtures presented in their living environment. However, the underlying toxic mechanisms employed by soil animals to cope with such combined pollution have yet to be explored. This investigation aimed to reveal the changes in cellular and mRNA levels under chlorpyrifos (CPF) and lambda-cyhalothrin (LCT) co-exposures in earthworms (Eisenia fetida). Results exhibited that the combination of CPF and LCT triggered an acute synergistic influence on the animals. Most exposures resulted in significant alterations in the activities of total superoxide dismutase (T-SOD), copper/zinc superoxide dismutase (Cu/Zn-SOD), caspase 3, and carboxylesterase (CarE) compared to the basal level. Moreover, when exposed to chemical mixtures, the transcription levels of four genes [heat shock protein 70 (hsp70), gst, sod, and calreticulin (crt)] also displayed more pronounced changes compared with their individual exposures. These changes in determined parameters indicated the occurrence of oxidative stress, cell death, detoxification dysfunction, and endoplasmic reticulum damage after co-exposure to CPF and LCT in E. fetida. The comprehensive examination of mixture toxicities of CPF and LCT at different endpoints would help to understand the overall toxicity they cause to soil invertebrates. The augmented deleterious effect of these pesticides in a mixture suggested that mixture toxicity assessment was necessary for the safety evaluation and application of pesticide mixtures.

Abstract Objective Little is known about the magnitude of the relation of ambient fine particulate matter (PM2.5) constituents with hyperuricemia and serum uric acid (SUA) levels. Therefore, we aimed to assess the associations and to identify the most hazardous constituent. Methods This study included 72,840 participants from the China Multi-Ethnic Cohort. Annual average concentrations of PM2.5 mass and its major 7 constituents were matched to individuals by residential address. SUA levels exceeding 7.0 mg/dL (417 μmol/L) for men and 6.0 mg/dL (357 μmol/L) for women were considered to be hyperuricemia. Multiple logistic and linear regressions were performed on the association of single exposure to PM2.5 constituents with hyperuricemia and SUA, separately. The weighted quantile sum method was applied to examine the joint effect of PM2.5 constituents on hyperuricemia/SUA. Results Significant positive associations were discovered between PM2.5 constituents and SUA/hyperuricemia. For example, the odds ratio (95% confidence interval) of hyperuricemia for per standard deviation increase of PM2.5 mass, black carbon, organic matter, ammonium, and nitrate concentrations were 1.22 (1.12–1.32), 1.17 (1.08–1.27), 1.20 (1.10–1.31), 1.21 (1.11–1.31), and 1.28 (1.18–1.40), respectively. The joint exposure to PM2.5 constituents was significantly positively correlated with hyperuricemia (1.09, 1.05–1.14) and SUA (1.05, 1.03–1.06). And the weight of nitrate was the largest (0.668 for hyperuricemia, 0.586 for SUA). Conclusions Our findings suggest that long-term exposure to PM2.5 constituents is associated with increased SUA levels and a higher risk of hyperuricemia. In particular, nitrate seems to be the main contributor. This study may help prevent hyperuricemia by promoting the introduction of precise preventive measures. Graphical Abstract

Objective: Little is known about the magnitude of the relation of ambient fine particulate matter (PM2.5) constituents with hyperuricemia and serum uric acid (SUA) levels. Therefore, we aimed to assess the associations and to identify the most hazardous constituent. Methods: This study included 72,840 participants from the China Multi-Ethnic Cohort. Annual average concentrations of PM2.5 mass and its major 7 constituents were matched to individuals by residential address. SUA levels exceeding 7.0 mg/dL (417 μmol/L) for men and 6.0 mg/dL (357 μmol/L) for women were considered to be hyperuricemia. Multiple logistic and linear regressions were performed on the association of single exposure to PM2.5 constituents with hyperuricemia and SUA, separately. The weighted quantile sum method was applied to examine the joint effect of PM2.5 constituents on hyperuricemia/SUA. Results: Significant positive associations were discovered between PM2.5 constituents and SUA/hyperuricemia. For example, the odds ratio (95% confidence interval) of hyperuricemia for per standard deviation increase of PM2.5 mass, black carbon, organic matter, ammonium, and nitrate concentrations were 1.22 (1.12–1.32), 1.17 (1.08–1.27), 1.20 (1.10–1.31), 1.21 (1.11–1.31), and 1.28 (1.18–1.40), respectively. The joint exposure to PM2.5 constituents was significantly positively correlated with hyperuricemia (1.09, 1.05–1.14) and SUA (1.05, 1.03–1.06). And the weight of nitrate was the largest (0.668 for hyperuricemia, 0.586 for SUA). Conclusions: Our findings suggest that long-term exposure to PM2.5 constituents is associated with increased SUA levels and a higher risk of hyperuricemia. In particular, nitrate seems to be the main contributor. This study may help prevent hyperuricemia by promoting the introduction of precise preventive measures. Highlights: Considering the constituents of PM2.5 in assessing its toxicity and health effects. Exposure to PM2.5 constituents was related with serum uric acid and hyperuricemia. Nitrate contributed most to serum uric acid levels and hyperuricemia. The results of joint effects were verified by two different statistical methods. A large-scale sample of nearly 100,000 subjects from diverse ethnic backgrounds. [ABSTRACT FROM AUTHOR]

Isolated effects of single endocrine-disrupting chemicals (EDCs) on male reproductive health have been studied extensively, but their mixture effect remains unelucidated. Previous research has suggested that consuming diet enriched in omega-3 polyunsaturated fatty acids (PUFA) might be beneficial for reproductive health, whether omega-3 PUFA could moderate the effect of EDCs mixture on semen quality remains to be explored. In this study of 155 male recruited from a reproductive health center in China, we used targeted-exposomics to simultaneously measure 55 EDCs in the urine for exposure burden. Regression analyses were restricted to highly detected EDCs (≥55%, n = 34), and those with consistently elevated risk were further screened and brought into mixture effect models (Bisphenol A, ethyl paraben, methyl paraben [MeP], benzophenone-1 [BP1], benzophenone-3, mono(3-carboxypropyl) phthalate [MCPP]). Bayesian Kernel Machine Regression (BKMR) and quantile-based g-computation (QGC) models demonstrated that co-exposure to top-ranked EDCs was related to reduced sperm total (β = −0.18, 95%CI: −0.29 – −0.07, P = 0.002) and progressive motility (β = −0.27, 95%CI: −0.43 – −0.10, P = 0.002), but not to lower semen volume. BP1, MeP and MCPP were identified as the main effect driver for deteriorated sperm motion parameters using mixture model analyses. Seminal plasma fatty acid profiling showed that high omega-3 PUFA status, notably elevated docosapentaenoic acid (DPA, C22:5n-3) status, moderated the association between MCPP and sperm motion parameters (total motility: β = 0.26, 95%CI: 0.01 – −0.51, Pinteraction = 0.047; progressive motility: β = 0.64, 95%CI: 0.23 – 1.05, Pinteraction = 0.003). Co-exposure to a range of EDCs is mainly associated with deteriorated sperm quality, but to a lesser extent on sperm quantity, high seminal plasma DPA status might be protective against the effect. Our work emphasizes the importance of exposomic approach to assess chemical exposures and highlighted a new possible intervention target for mitigating the potential adverse effect of EDCs on semen quality.

Catalytic destruction is an ascendant technology for the abatement of volatile organic compounds (VOCs) originating from solvent-based industrial processes. The varied composition tends to influence each VOC's catalytic behavior in the reaction mixture. We investigated the catalytic destruction of multi-component VOCs including dichloromethane (DCM) and ethyl acetate (EA), as representatives from pharmaceutical waste gases, over co-supported H x PO 4 -RuO x /CeO 2 catalyst. A mutual inhibitory effect relating to concentrations because of competitive adsorption was verified in the binary VOCs oxidation and EA posed a more negative effect on DCM oxidation owing to EA's superior adsorption capacity. Preferential adsorption of EA on acidic sites (H x PO 4 /CeO 2) promoted DCM activation on basic sites (O2−) and the dominating EA oxidation blocked DCM's access to oxidation centers (RuO x /CeO 2), resulting in boosted monochloromethane yield and increased chlorine deposition for DCM oxidation. The impaired redox ability of Ru species owing to chlorine deposition in turn jeopardized deep oxidation of EA and its by-products, leading to increased gaseous by-products such as acetic acid originating from EA pyrolysis. Notably, DCM at low concentration slightly promoted EA conversion at low temperatures with or without water, consistent with the enhanced EA adsorption in co-adsorption analyses. This was mainly due to that DCM impeded the shielding effect of hydrolysate deposition from rapid EA hydrolysis depending on the decreased acidity. Moreover, water benefited EA hydrolysis but decreased CO 2 selectivity while the generated water derived from EA was likely to affect DCM transformation. This work may provide theoretical guidance for the promotion of applied catalysts toward industrial applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Litter decomposition is a key step in global biogeochemical cycling. In forest ecosystems, litter from different tree spec1ies often decompose together. Although species diversity is widely acknowledged to accelerate decomposition through the regulation of nutrient transfer between litter and decomposer communities, the underlying mechanism remains unclear. To explore the association between the bacterial community and mixed-litter chemical transformation, we conducted a one-year litter mixing decomposition experiment using leaf litter from four dominant tree species in Mount Tai (Eastern China), Robinia pseudoacacia, Quercus acutissima, Pinus tabulaeformis, and Pinus densiflora. Our results showed that: 1) Mass loss of leaf litter mixtures was significantly faster than that of leaf litter monocultures, except for R. pseudoacacia. Litter mixtures without R. pseudoacacia showed non-additive synergistic effects, whereas litter mixtures with R. pseudoacacia exerted additive effects; 2) Litter species in the absence of R. pseudoacacia significantly decreased the nutrient retention rates of litter mixtures compared to those of monocultures; 3) Litter mixtures with or without R. pseudoacacia showing additive and non-additive effects in monocultures had a distinct bacterial community structure; 4) Bacterial community structure was also modified by initial litter traits; carbon (C), nitrogen (N), and phosphorus (P) concentrations in monocultures; N/P and C/N ratios of mixtures with R. pseudoacacia; and the lignin/N ratio of mixtures without R. pseudoacacia. Overall, these findings indicate that tree species diversity controls decomposition and nutrient cycling, implying that an appropriate species community composition is beneficial to maintaining forest ecosystems.

Heavy metals and pesticides are significant pollutants in aquatic environments, often leading to combined pollution and exerting toxic effects on aquatic organisms. With the rapid growth of modern industry and agriculture, heavy metal cadmium (Cd) and pesticide triazophos (TRI) are frequently detected together in various water bodies, particularly in agricultural watersheds. However, the combined toxic mechanisms of these pollutants on fish remain poorly understood. This experiment involved a 21-day co-exposure of Cd and TRI to the hook snout carp Opsariichthys bidens to investigate the toxic effects on liver tissues at both enzymatic and transcriptional levels. Biochemical analysis revealed that both individual and combined exposures significantly increased the content or activity of caspase-3 (CASP-3) and malondialdehyde (MDA). Moreover, the impact on these parameters was greater in the combined exposure groups compared to the corresponding individual exposure groups. These findings suggested that both individual and combined exposures could induce mitochondrial dysfunction and lipid peroxidation damage, with combined exposure exacerbating the toxicological effects of each individual pollutant. Furthermore, at the molecular level, both individual and combined exposures upregulated the expression levels of cu-sod , cat , and erβ , while downregulating the expression of il-1. Similar to the patterns observed in the biochemical parameters, the combined exposure group exhibited a greater impact on the expression of these genes compared to the individual exposure groups. These results indicated that exposure to Cd, TRI, and their combination induced oxidative stress, endocrine disruption, and immunosuppression in fish livers, with more severe effects observed in the combined exposure group. Overall, the interaction between Cd and TRI appeared to be synergistic, shedding light on the toxic mechanisms by which fish livers responded to these pollutants. These findings contributed to the understanding of mixture risk assessment of pollutants and were valuable for the conservation of aquatic resources. [Display omitted] • Triazophos exhibited higher acute toxicity to the hook snout carps than cadmium. • Combination of cadmium and triazophos showed synergistic acute toxicity. • Cadmium and triazophos exposures induced changes in caspase-9 and MDA levels. • Expressions of ap , klf2α , il-1 , and erα were obviously altered by the co-exposure. [ABSTRACT FROM AUTHOR]

Mycotoxins and pesticides frequently coexist in agricultural commodities on a global scale. The potential transgenerational consequences induced by these substances pose a significant threat to human health. However, there is a lack of data concerning the effects of co-contamination by these chemicals in the F1 generation following parental exposure. This investigation delved into the mixture effects of T-2 toxin (T-2) and epoxiconazole (EPO) on the offspring of zebrafish (Danio rerio). The findings revealed that exposure across generations to a combination of T-2 and EPO resulted in toxicity in the larvae of the F1 generation. This was demonstrated by a significant increase in the levels or activities of malondialdehyde (MDA), thyroxine (T4), Caspase3, and cas9 , along with a decrease in the levels of cyp19a , ERα , and ERβ. These outcomes suggested that cross-generational exposure to T-2 and EPO in D. rerio disrupted oxidative balance, induced cell apoptosis, and affected the endocrine system. Moreover, these effects were magnified when the F1 generation was continuously exposed to these compounds. Notably, these adverse effects could persist in subsequent generations without additional exposure. This study underscored the potential dangers associated with the simultaneous presence of T-2 and EPO on the development of fish offspring and the resulting environmental hazards to aquatic ecosystems. These findings emphasized the significant health risks posed by cross-generational exposure and highlighted the need for additional legislative measures to address these concerns. [Display omitted] • T-2 toxin mixed with epoxiconazole exhibited synergistic acute effects on zebrafish. • Co-effects of T-2 toxin and epoxiconazole can be transmitted by parental exposure. • Oxidative stress was affected in all the single and mixture exposures. • Co-exposure of T-2 and epoxiconazole mainly affected gene expression of HPG axis. [ABSTRACT FROM AUTHOR]

As the global aging process accelerates, the health challenges posed by sarcopenia among middle-aged and older adults are becoming increasingly prominent. However, the available evidence on the adverse effects of air pollution on sarcopenia is limited, particularly in the Western Pacific region. This study aimed to explore relationships of multiple air pollutants with sarcopenia and related biomarkers using the nationally representative database. Totally, 6585 participants aged over 45 years were enrolled from the China Health and Retirement Longitudinal Study (CHARLS) in 2011 and 3443 of them were followed up until 2015. Air pollutants were estimated from high-resolution satellite-based spatial-temporal models. In the cross-sectional analysis, we used generalized linear regression, unconditional logistic regression analytical and restricted cubic spline (RCS) methods to assess the single-exposure and non-linear effects of multiple air pollutants on sarcopenia and related surrogate biomarkers (serum creatinine and cystatin C). Several popular mixture analysis techniques such as Bayesian kernel machine regression (BKMR), weighted quantile sum (WQS) regression, and quantile-based g-computation (Qgcomp) were further used to examinate the combined effects of multiple air pollutants. Logistic regression was used to further analyze the longitudinal association between air pollution and sarcopenia. Each interquartile range increase in PM 2.5 , PM 10 and NO 2 was significantly associated with an increased risk of sarcopenia, with adjusted odds ratios (aORs) of 1.09 [95 % confidence interval (CI): 1.01, 1.20], 1.24 (95 % CI: 1.14, 1.35) and 1.18 (95 % CI: 1.08, 1.28), respectively. Our findings also showed that five air pollutants were significantly associated with the sarcopenia index. In addition, employing a mixture analysis approach, we confirmed significant combined effects of air pollution mixtures on sarcopenia risk and associated biomarkers, with PM 10 and PM 2.5 identified as major contributors to the combined effect. The results of the exposure-response (E-R) relationships, subgroup analysis, longitudinal analysis and sensitivity analysis all showed the unfavorable impact of air pollution on sarcopenia risk and related vulnerable populations. Single-exposure and co-exposure to multiple air pollutants were positively associated with sarcopenia among middle-aged and older adults in China. Our study provided new evidence that air pollution mixture was significantly associated with sarcopenia related biomarkers. [Display omitted] • Ambient PM 2.5 , PM 10 , and NO 2 were positively associated with risk of sarcopenia. • Positive joint effect of air pollution mixtures with sarcopenia risk was revealed. • Both individual and mixed air pollutants were negatively associated with sarcopenia index. • PM 10 and PM 2.5 dominated the joint effects on sarcopenia and sarcopenia index. • New findings were based on nationally representative Chinese adults (age ≥ 45 years). [ABSTRACT FROM AUTHOR]

The growing use of Lanthanides in new technologies has increased their anthropogenic releases into the aquatic environment over the last decades. However, knowledge on their ecotoxicological impacts is still incomplete, especially with regard to biological effects of Lanthanides mixtures and the possible regular variation in toxicity along the Lanthanides series. The present study evaluated the individual toxicity of all Lanthanides and the toxicity of mixtures of three of them, namely Neodymium (Nd3+), Gadolinium (Gd3+), and Ytterbium (Yb3+) on Danio rerio fibroblast-like cells (ZF4). Individual and mixtures toxicity of Neodymium (Nd3+) and Ytterbium (Yb3+) were also assessed on Danio rerio hepatic cells (ZFL) and Oncorhynchus mykiss epithelial cells (RTgill-W1). The measured Lanthanide concentrations were close to the nominal ones in the culture media of ZF4, ZFL, and RTgill-W1 cells (85–99%). A toxic impact was observed on the three fish cell lines exposed to all Lanthanides tested individually. RTgill-W1 appeared as the less sensitive cells, compared to the two others. Four Lanthanides, Erbium (Er3+), Thulium (Tm3+), Ytterbium (Yb3+) and Lutetium (Lu3+) showed a higher toxicity than the others on ZF4 cells but no correlation could be established between the toxicity of Lanthanides and the order of the elements within the Lanthanides series. Exposures to binary mixtures highlighted the presence of synergistic effects on cell viability for all cell lines. [ABSTRACT FROM AUTHOR]

Environmental chemicals have been indicated to cause disruption of thyroid homeostasis in human populations. However, previous studies mostly focused on single group of chemicals. Herein, we investigate the independent and combined effects of multiple pollutants on thyroid homeostasis, including thyroid-stimulating hormone (TSH), total and free thyroxine (tT4 and fT4) and total and free triiodothyronine (tT3 and fT3) in elderly people. These environmental pollutants (n = 144) are from ten categories, including phenols, parabens, perfluoroalkyl substances (PFASs), polychlorinated biphenyls (PCBs), phthalate esters (PAEs), polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), organophosphate pesticides (OPPs), synthetic pyrethroids (SPs), herbicides, and metals. Few studies have evaluated the health risks of these 144 chemicals, especially their joint effects. In single-pollutant evaluations, multiple linear regression (MLR) models were used to estimate the independent associations between multiple exposures and thyroid biomarkers. In multi-pollutant evaluations, elastic net regression and Bayesian kernel machine regression (BKMR) models were used to estimate the combined associations. The MLR models showed that 41 chemicals were significantly related to THs levels. BKMR models revealed the most important chemical groups: metals for TSH, PAHs, SPs and PCBs for tT4, herbicides and SPs for tT3. This study will contribute to the understanding of multipollutant exposure and help prioritize specific chemical groups related to thyroid hormone disruption. [Display omitted] • The independent and joint effects of 144 chemicals on THs were assessed. • Single models observed 41 chemicals significantly associated with THs levels. • Metals most contributed to decreased TSH, SP mixtures contributed to increased tT3. • SP and PCB mixtures contributed to decreased tT4。. • Cumulative exposure to mixtures may play an important role in thyroid homeostasis. [ABSTRACT FROM AUTHOR]

Early-life exposure to phthalates alters behaviors in animals. However, epidemiological evidence on childhood phthalate exposure and attention-deficit/hyperactivity disorder (ADHD) behaviors is limited. This study included 243 children from the ReCHARGE (Revisiting Childhood Autism Risks from Genetics and Environment) study, who were previously classified as having autism spectrum disorder (ASD), developmental delay, other early concerns, and typical development in the CHARGE case-control study. Twenty phthalate metabolites were measured in spot urine samples collected from children aged 2–5 years. Parents reported on children's ADHD symptoms at ages 8–18 years using Conners-3 Parent Rating Scale. Covariate-adjusted negative binomial generalized linear models were used to investigate associations between individual phthalate metabolite concentrations and raw scores. Weighted quantile sum (WQS) regression with repeated holdout validation was used to examine mixture effects of phthalate metabolites on behavioral scores. Effect modification by child sex was evaluated. Among 12 phthalate metabolites detected in >75% of the samples, higher mono-2-heptyl phthalate (MHPP) was associated with higher scores on Inattentive (β per doubling = 0.05, 95% confidence interval [CI]: 0.02, 0.08) and Hyperactive/Impulsive scales (β = 0.04, 95% CI: 0.00, 0.07), especially among children with ASD. Higher mono-carboxy isooctyl phthalate (MCiOP) was associated with higher Hyperactivity/Impulsivity scores (β = 0.07, 95% CI: −0.01, 0.15), especially among typically developing children. The associations of the molar sum of high molecular weight (HMW) phthalate metabolites and a phthalate metabolite mixture with Hyperactivity/Impulsivity scores were modified by sex, showing more pronounced adverse associations among females. Exposure to phthalates during early childhood may impact ADHD behaviors in middle childhood and adolescence, particularly among females. Although our findings may not be broadly generalizable due to the diverse diagnostic profiles within our study population, our robust findings on sex-specific associations warrant further investigations. • Phthalate metabolites at 2–5 years and ADHD behaviors at 8–18 years were studied. • MHPP was associated with more ADHD behaviors, especially among children with ASD. • Associations of a phthalate mixture with ADHD behaviors were modified by child sex. • Among females, HMW phthalates were associated with more hyperactivity/impulsivity. [ABSTRACT FROM AUTHOR]

Farmland soil organisms frequently encounter pesticide mixtures presented in their living environment. However, the underlying toxic mechanisms employed by soil animals to cope with such combined pollution have yet to be explored. This investigation aimed to reveal the changes in cellular and mRNA levels under chlorpyrifos (CPF) and lambda -cyhalothrin (LCT) co-exposures in earthworms (Eisenia fetida). Results exhibited that the combination of CPF and LCT triggered an acute synergistic influence on the animals. Most exposures resulted in significant alterations in the activities of total superoxide dismutase (T-SOD), copper/zinc superoxide dismutase (Cu/Zn-SOD), caspase 3, and carboxylesterase (CarE) compared to the basal level. Moreover, when exposed to chemical mixtures, the transcription levels of four genes [heat shock protein 70 (hsp70), gst , sod , and calreticulin (crt)] also displayed more pronounced changes compared with their individual exposures. These changes in determined parameters indicated the occurrence of oxidative stress, cell death, detoxification dysfunction, and endoplasmic reticulum damage after co-exposure to CPF and LCT in E. fetida. The comprehensive examination of mixture toxicities of CPF and LCT at different endpoints would help to understand the overall toxicity they cause to soil invertebrates. The augmented deleterious effect of these pesticides in a mixture suggested that mixture toxicity assessment was necessary for the safety evaluation and application of pesticide mixtures. [Display omitted] • Lambda -cyhalothrin held a lower acute effect on the earthworms than chlorpyrifos. • Co-exposure of chlorpyrifos and lambda -cyhalothrin triggered synergistic toxicity. • Activity of caspase3 was significantly inhibited in the co-exposure of pesticides. • Hsp70 was a potential biomarker for chlorpyrifos mixed with lambda -cyhalothrin. [ABSTRACT FROM AUTHOR]

Background: The replanting of broadleaved trees in pure coniferous plantations is widely implemented, as mixed plantations are generally more stable and functional. However, the effect of interspecific interactions between broadleaved and coniferous trees on internal nutrient cycles of conifers remains unclear. Methods: We selected pure coniferous plantations of a native (Pinus massoniana) and an exotic (P. elliottii) pine species and their corresponding mixed plantations with broadleaved trees (Schima superba) in subtropical China, and measured the nitrogen (N) and phosphorus (P) contents in the rhizosphere soils, fine roots, twigs, needles and needle litter of pines. We calculated the root capture, needle resorption and translocation of N and P by pines to determine the mobility of nutrients in trees. Results: Although the N and P in the rhizosphere soils increased due to the replanting of broadleaved trees, the N and P contents in the aboveground tissues of the two pine species did not increase in mixed plantations. Mixed planting had a negative effect on the N and P capture of native pine and a positive effect on that of exotic pine. The N and P resorption efficiencies increased in native pine but were unchanged in exotic pine after the replanting of S. superba. Native pine preferentially employed an aboveground nutrient resorption strategy, whereas exotic pine tended to adopt a belowground nutrient capture strategy after replanting. Translocation of N and P in trees was detected, which reflected the trade-offs between root nutrient capture and needle nutrient resorption. Conclusions: The effect of mixed planting varied between the species of native and exotic pines, and the internal nutrient cycles of both pine species might be dominated by interspecific interaction effects on nutrients rather than soil nutrients. Our study highlights the importance of selecting suitable broadleaved species for replanting in coniferous plantations. [ABSTRACT FROM AUTHOR]

Background: Increased use of renewable resources like sustainably produced wood in construction or for all sorts of long-lived products is considered to contribute to reducing society's carbon footprint. However, as a natural, biological material, wood and wood products emit specific volatile organic compounds (VOCs). Therefore, the evaluation of possible health effects due to wood emissions is of major interest. Objectives: We investigated the effects of an exposure to multiple wood-related VOCs on asthma development. Methods: A murine asthma model was used to evaluate possible allergic and inflammatory effects on the lung after short- or long-term and perinatal exposure to pinewood or oriented strand board (OSB). In addition, wood-related VOCs were measured within the German prospective mother–child cohort LINA and their joint effect on early wheezing or asthma development in children until the age of 10 was estimated by Bayesian kernel machine regression (BKMR) stratifying also for family history of atopy (FHA). Results: Our experimental data show that neither pinewood nor OSB emissions even at high total VOC levels and a long-lasting exposure period induce significant inflammatory or asthma-promoting effects in sensitized or non-sensitized mice. Moreover, an exposure during the vulnerable time window around birth was also without effect. Consistently, in our mother–child cohort LINA, an exposure to multiple wood-related VOCs during pregnancy or the first year of life was not associated with early wheezing or asthma development in children independent from their FHA. Conclusion: Our findings indicate that emissions from wood and wood products at levels commonly occurring in the living environment do not exert adverse effects concerning wheezing or asthma development.

Some prenylated polyphenols originating from hops, which are thus natural constituents of beer, have been discussed critically for their agonistic potential toward estrogen receptors. So far, little attention has been attributed to the fact that humans are typically not exposed to isolated compounds, but to mixtures which for example might comprise in addition to hop flavonoids further xenoestrogens, e.g., certain pesticides used for plant protection of hops and barley. Thus, we used the alkaline phosphatase assay to assess combinatory estrogenic effects of three signature compounds – xanthohumol, 8-prenylnaringenin and iso-xanthohumol–on Ishikawa cells in a combination that resembled the concentration ratios observable in beer. Moreover, we added this natural flavonoid pattern to a mixture of representative estrogenic pesticides to assess their combined effects. Using state-of-the-art statistical tools, we observed cumulative to slightly synergistic effects between isolated flavonoids as well as the flavonoid and the pesticide mixture. Of potential importance, these effects were found at low nanomolar hop polyphenol concentrations that one can reasonably expect to occur in vivo after the consumption of strongly hopped beer. Taken together, our results imply that cumulative/synergistic estrogenicity should be explored in detail and urgently be incorporated into risk assessment of prenylated chalcones.

[Display omitted] • A total of 55 urinary EDCs were measured in the study population. • Co-exposure to EDCs was strongly related to diminished sperm quality, not quantities. • High seminal plasma fatty acid DPA status attenuated the negative association. Isolated effects of single endocrine-disrupting chemicals (EDCs) on male reproductive health have been studied extensively, but their mixture effect remains unelucidated. Previous research has suggested that consuming diet enriched in omega-3 polyunsaturated fatty acids (PUFA) might be beneficial for reproductive health, whether omega-3 PUFA could moderate the effect of EDCs mixture on semen quality remains to be explored. In this study of 155 male recruited from a reproductive health center in China, we used targeted-exposomics to simultaneously measure 55 EDCs in the urine for exposure burden. Regression analyses were restricted to highly detected EDCs (≥55%, n = 34), and those with consistently elevated risk were further screened and brought into mixture effect models (Bisphenol A, ethyl paraben, methyl paraben [MeP], benzophenone-1 [BP1], benzophenone-3, mono(3-carboxypropyl) phthalate [MCPP]). Bayesian Kernel Machine Regression (BKMR) and quantile-based g-computation (QGC) models demonstrated that co-exposure to top-ranked EDCs was related to reduced sperm total (β = −0.18, 95%CI: −0.29 – −0.07, P = 0.002) and progressive motility (β = −0.27, 95%CI: −0.43 – −0.10, P = 0.002), but not to lower semen volume. BP1, MeP and MCPP were identified as the main effect driver for deteriorated sperm motion parameters using mixture model analyses. Seminal plasma fatty acid profiling showed that high omega-3 PUFA status, notably elevated docosapentaenoic acid (DPA, C22:5n-3) status, moderated the association between MCPP and sperm motion parameters (total motility: β = 0.26, 95%CI: 0.01 – −0.51, P interaction = 0.047; progressive motility: β = 0.64, 95%CI: 0.23 – 1.05, P interaction = 0.003). Co-exposure to a range of EDCs is mainly associated with deteriorated sperm quality, but to a lesser extent on sperm quantity, high seminal plasma DPA status might be protective against the effect. Our work emphasizes the importance of exposomic approach to assess chemical exposures and highlighted a new possible intervention target for mitigating the potential adverse effect of EDCs on semen quality. [ABSTRACT FROM AUTHOR]

The association between oxidative stress and exposure to bisphenols, parabens, phenols, polycyclic aromatic hydrocarbons (PAH), and volatile organic compounds (VOCs) has been investigated by many in vitro and in vivo studies. However, most of these findings are based on cross-sectional studies, as a result of which the combined effects of these compounds have been rarely analyzed. In this study, our objective was to assess urinary bisphenols, parabens, PAHs, and VOCs, in relation to oxidative stress during pre-and postpartum periods, analyze the association between these chemicals and oxidative stress via repeated measurements using a linear mixed model (LMM), and evaluate the combined effects exerted by these chemicals on oxidative stress using Bayesian Kernel Machine Regression (BKMR). A total 529 urine samples were collected from 242 pregnant women during the 1st and 2nd trimesters, as well as postpartum follow-ups. Three bisphenols, four parabens, benzopheone-3 (BP-3), triclosan (TCS), four PAHs, two VOCs, and 3- phenoxy-benzoic acid (3-PBA) were analyzed. We also measured 8-hydroxydeoxyguanosine (8-OHdG) and malondialdehyde (MDA), which serve as oxidative stress biomarkers in maternal urine samples. During this period, 8-OHdG decreased steadily, whereas MDA increased during pregnancy and decreased after childbirth. LMM indicated that Bisphenol A, Prophyl-paraben, BP-3, and 1-hydroxypyrene (1-OHP) showed a significant association with increased MDA levels. The BKMR models revealed that the mixture effect exerted by these 16 chemicals had changed MDA levels, which indicate oxidative stress, and that both Butyl Paraben (BP) and 1-hydroxypyrene (1-OHP) had contributed to such oxidative stress. Mixtures of each subgroup (bisphenols, parabens, and PAHs) were associated with increased MDA levels. These findings suggest that exposure to some phenols and PAHs during pre- and post-partum stages may cause oxidative stress, and that exposure to these chemicals should be minimized during this period. [Display omitted] • 8-OHdG levels decreased steadily during prepartum and postpartum periods. • BPA, PP, BP-3, and 1-OHP were linked to increased oxidative stress, especially MDA. • A mixture of 16 chemicals associated with the MDA of oxidative stress. • BP and 1-OHP were contributors to oxidative stress in mixture effect model. [ABSTRACT FROM AUTHOR]

The main aim of the present research is to measure the nucleate boiling heat transfer coefficient (BHTC) of aqueous glycol nano-suspension as a coolant around a horizontal heater. Alumina nanoparticles were added to the base fluid at a volumetric concentration of 1% to improve the thermal conductivity of the nano-suspension. The pressure of the system was set to the atmospheric pressure, and the coolant was tested at different applied heat fluxes (HF) ranged from 0 to 90 kW m−2 and volumetric concentration of 0–40% of the heavier component. Two zones of heat transfer were identified, including a natural convection zone and nucleate boiling one mixed with bubble formation and bubble interactions. Results also showed that the HTC of the nano-suspension is smaller than those recorded for the pure water. A rough comparison was made to examine the accuracy of the developed equations for estimating the BHTC value against the experimental data. It was found that the developed equations are not accurate for the data measured in the free convection region. Thus, the Churchill-Chu correlation was recommended for estimating the BHTC in the free convection area of heat transfer. Also, the effect of operating parameters such as HF and volumetric concentration on the pool boiling HTC of the solution was studied. [ABSTRACT FROM AUTHOR]

Chirality plays a fundamental role in nature, but its detection and quantification still face many limitations. To date, the enantiospecific analysis of mixtures necessarily requires prior separation of the individual components. The simultaneous enantiospecific detection of multiple chiral molecules in a mixture represents a major challenge, which would lead to a significantly better understanding of the underlying biological processes; for example, via enantiospecifically analysing metabolites in their native environment. Here, we report on the first in situ enantiospecific detection of a thirty‐nine‐component mixture. As a proof of concept, eighteen essential amino acids at physiological concentrations were simultaneously enantiospecifically detected using NMR spectroscopy and a chiral solvating agent. This work represents a first step towards the simultaneous multicomponent enantiospecific analysis of complex mixtures, a capability that will have substantial impact on metabolism studies, metabolic phenotyping, chemical reaction monitoring, and many other fields where complex mixtures containing chiral molecules require efficient characterisation. [ABSTRACT FROM AUTHOR]

The mixture effect of the long-term variations is a main challenge in single channel singular spectrum analysis (SSA) for the reconstruction of the annual signal from GRACE data. In this paper, a nonlinear long-term variations deduction method is used to improve the accuracy of annual signal reconstructed from GRACE data using SSA. Our method can identify and eliminate the nonlinear long-term variations of the equivalent water height time series recovered from GRACE. Therefore the mixture effect of the long-term variations can be avoided in the annual modes of SSA. For the global terrestrial water recovered from GRACE, the peak to peak value of the annual signal is between 1.4 cm and 126.9 cm, with an average of 11.7 cm. After the long-term and the annual term have been deducted, the standard deviation of residual time series is between 0.9 cm and 9.9 cm, with an average of 2.1 cm. Compared with the traditional least squares fitting method, our method can reflect the dynamic change of the annual signal in global terrestrial water, more accurately with an uncertainty of between 0.3 cm and 2.9 cm. [ABSTRACT FROM AUTHOR]

Environmental exposure to arsenic (As) and fluoride (F) in the recent year has been increased because of excessive use of naturally contaminated ground water. Surface water is also regularly contaminated with these elements in various industrial areas. Arsenicosis and fluorosis upon individual exposure of As and F are reported in many studies. A syndrome of endemic As poisoning and fluorosis occurs during concurrent exposure of As and F. Previous reports showed synergistic, antagonistic and independent effects of these two compounds, although few recent reports also revealed antagonistic effects after co‐exposure. Interaction during intestinal absorption and influence of F on As metabolism might be the cause of antagonism. The synergism/antagonism is thought to depend on the dose and duration of the co‐exposure. However, the detailed mechanism is still not fully understood and needs further studies. Removal technologies of As and F from contaminated water is available but removal of such contaminants from food is yet to be developed. Antioxidants are useful to mitigate the toxic effects of As and F. This review focused on the effect of co‐exposure, amelioration as well as removal techniques of As and F. Several parts of the world are facing serious problems due to detrimental effects of arsenic (As) and fluoride (F). Mixture effects of As and F have shown ambiguity based on dose of exposure, duration of exposure and types of model organism. Use of ameliorative agents and removal techniques are the best options of obtaining relief from such toxicity. [ABSTRACT FROM AUTHOR]

The study on mixture effect of karst groundwater and surface water in karst groundwater system is essential for rational development, utilization and protection of karst groundwater resources. On the basis of field investigation and sampling data, mixture effect of karst groundwater and surface water in the Liulin Spring area was explored using hydrogeochemical simulation methods and environmental isotopes tracing techniques, then the mixture ratio was calculated. The results were utilized to estimate quantity of rainfall infiltration in typical recharge area. The results show that the mixture between groundwater and surface water occurred near the surface water leakage belts during karst groundwater flowing from recharge area to runoff area and from runoff area to discharge area with a ratio of 3∶1 and 2∶3. In the recharge area near Tianjiahui, the mean annual quantity of rainfall infiltration is estimated with a value of about 0.07 m3/s. [ABSTRACT FROM AUTHOR]

Catalytic total oxidation is an efficient technique for treating VOCs, which are mainly emitted by solvent-based industrial processes. However, studies of the catalytic oxidation of VOCs in combination with other pollutants are very limited, despite the fact that this is a key step of knowledge before industrial application. During the oxidation reaction, the behavior of a molecule may change depending on the reaction mixture. For the treatment of an effluent loaded with VOCs, it is necessary to carefully select not only the catalytic material to be used but also the reaction conditions. Indeed, the catalytic oxidation of a component in a VOCs mixture is not predicted solely from the behavior of individual component. Thus, the objective of this small review is to carry out a study on the effect observed in the case of the oxidation of a VOCs mixture or in the presence of water, NOX or sulfur compounds.

Light availability is a crucial resource determining seedling survival, establishment, and growth. Competition for light is asymmetric, giving the taller individuals a competitive advantage for obtaining light resources. Species-specific traits, e.g., shade tolerance, rooting depth, and leaf morphology, determine their strategical growth response under limited resource availability and different competitive interactions. We established a controlled pot experiment using European beech, Norway spruce, and Douglas fir seedlings and applying three different light availability levels—10%, 20%, and 50%. The experiment’s main aim was to better understand the effects of light availability and competition type on the growth, growth allocation, and biomass production of recently planted seedlings. We planted four seedlings per pot in either monocultures or mixtures of two species. Relative height and diameter growth and aboveground woody biomass of seedlings increased with increasing light availability. All seedlings allocated more growth to height than diameter with decreasing light availability. Seedlings that reached on average greater height in the previous year allocated less growth to height in the following year. Additionally, there were general differences in growth allocation to the height between gymnosperms and angiosperms, but we did not find an effect of the competitor’s identity. Our mixture effect analysis trends suggested that mixtures of functionally dissimilar species are more likely to produce higher biomass than mixtures of more similar species such as the two studied conifers. This finding points towards increased productivity through complementarity.

Abstract Perfluoroalkyl acids (PFAAs) are environmental contaminants of concern in both food and drinking water. PFAA fate in agricultural soil is an important determinant of PFAA contamination of groundwater and crops. The fate of C4-C14 perfluorinated carboxylic acids (PFCAs) and two perfluorinated sulfonic acids (PFSAs) in an agricultural soil was studied in a field lysimeter experiment. Soil was spiked with PFAAs at four different levels and crops were planted. PFAA concentrations in soil were measured at the beginning and end of the growing season. Lysimeter drainage water was collected and analysed. The concentrations of all PFAAs decreased in the surface soil during the growing season, with the decrease being negatively correlated with the number of fluorinated carbons in the PFAA molecule. PFAA transfer to the drainage water was also negatively correlated with the number of fluorinated carbons. For the C11-C14 PFCAs most of the decrease in soil concentration was attributed to the formation of non-extractable residues. For the remaining PFAAs leaching was the dominant removal process. Leaching was concentration dependent, with more rapid removal from the soils spiked with higher PFAA levels. Model simulations based on measured K d values under-predicted removal by leaching. This was attributed to mixture effects that reduced PFAA sorption to soil. Highlights • K d for C4-C14 PFCAs increased by 0.39–0.48 log units per perfluorinated carbon atom. • C4-C7 PFAAs were almost completely removed from the 60 cm deep lysimeter after 72 days. • Leaching (%) increased with the initial concentration of the PFAA mixture in the soil. • Modeling using measured K d values underestimated observed loss of PFAAs from soil. • Accelerated leaching was attributed to competition with other PFAS for sorption sites. [ABSTRACT FROM AUTHOR]

This work reports on gas phase catalytic ozonation of a binary mixture of toluene and acetone and compares it with catalytic ozonation of single component acetone and toluene. Catalytic ozonation was conducted at 25-90 °C on MnOx/γ-Al2O3 catalyst. XANES and EXAFS were used to identify formal oxidation state of Mn and local structure of manganese oxide in the catalyst. Absorption energy of Mn K-edge of the catalyst was determined to be 6553.86 eV indicating that the majority of manganese in the catalyst was in 3+ oxidation state. Catalytic ozonation in the mixture was favourable for removal of toluene, and repressive for removal of acetone. This was due to (a) lower apparent activation energy of catalytic ozonation of toluene (Ea, Toluene = 31 kJ mol−1 < Ea, Acetone = 40 kJ mol−1) that led to higher reactivity of toluene with active oxygen species, and (b) inhibitory effect of accumulated carbonaceous byproducts on the acetone removal. Increase of reaction temperature enhanced conversion of both compounds, decreased the gap between toluene and acetone conversions, and improved COx yield. Overall degradation pathway of toluene and acetone in the mixture was determined by identifying the reaction intermediates and carbonaceous deposits on the catalyst. The observed mixture effects helped to understand potentials and limitations of catalytic ozonation in treating mixture of VOCs, which will aid in developing commercial air treatment systems.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Evidence on liver injury and non-alcoholic fatty liver disease (NAFLD) from volatile organic compounds (VOCs) exposure is insufficient. A cross-sectional study including 3011 US adults from the National Health and Nutrition Examination Survey was conducted to explore the associations of urinary exposure biomarkers (EBs) for 13 VOCs (toluene, xylene, ethylbenzene, styrene, acrylamide, N,N-dimethylformamide, acrolein, crotonaldehyde, 1,3-butadiene, acrylonitrile, cyanide, propylene oxide, and 1-bromopropane) with liver injury biomarkers and the risk of NAFLD by performing single-chemical (survey weight regression) and mixture (Bayesian kernel machine regression [BKMR] and weighted quantile sum [WQS]) analyses. We found significant positive associations of EBs for toluene and 1-bromopropane with alanine aminotransferase (ALT), EBs for toluene, crotonaldehyde, and 1,3-butadiene with asparate aminotransferase (AST), EBs for 1,3-butadiene and cyanide with alkaline phosphatase (ALP), EBs for xylene and cyanide with hepamet fibrosis score (HFS), EBs for the total 13 VOCs (except propylene oxide) with United States fatty liver index (USFLI), and EBs for xylene, N,N-dimethylformamide, acrolein, crotonaldehyde, and acrylonitrile with NALFD; and significant inverse associations of EBs for ethylbenzene, styrene, acrylamide, acrolein, crotonaldehyde, 1,3-butadiene, acrylonitrile, cyanide, and propylene oxide with total bilirubin, EBs for ethylbenzene, styrene, acrylamide, acrolein, 1,3-butadiene, acrylonitrile, and cyanide with albumin (ALB), EBs for ethylbenzene, styrene, acrylamide, N,N-dimethylformamide, acrolein, crotonaldehyde, 1,3-butadiene, acrylonitrile, cyanide, and propylene oxide with total protein (TP), and EB for 1-bromopropane with AST/ALT (all P -FDR<0.05). In BKMR and WQS, the mixture of VOC-EBs was significantly positively associated with ALT, AST, ALP, HFS, USFLI, and the risk of NAFLD, while significantly inversely associated with TBIL, ALB, TP, and AST/ALT. VOCs exposure was associated with liver injury and increased risk of NAFLD in US adults. These findings highlight that great attention should be paid to the potential risk of liver health damage from VOCs exposure. [Display omitted] • Multiple VOCs exposure biomarkers were associated with liver injury and NAFLD • Mixture of 13 VOCs exposure biomarkers was associated with liver injury and NAFLD • Interaction effects existed among different VOCs on liver injury and NAFLD [ABSTRACT FROM AUTHOR]

It remains unclear whether manganese (Mn) exposure affects working memory (WM) in a sexually dimorphic manner. Further, no gold standard media exists to measure Mn, suggesting a combined blood and urinary Mn index may better capture the totality of exposure. We investigated the modification effect of child sex on the influence of prenatal Mn exposure on WM in school-age children, exploring two methodological frameworks to integrate exposure estimates across multiple exposure biomarkers. Leveraging the PROGRESS birth cohort in Mexico City, children (N = 559) ages 6–8 completed the between errors and strategy measures of the CANTAB Spatial Working Memory (SWM) task. Mn levels were assayed in blood and urine of mothers during the 2nd and 3rd trimesters and in umbilical cord blood from mothers and children at delivery. Weighted quantile sum regression estimated the association of a multi-media biomarker (MMB) mixture with SWM. We applied a confirmatory factor analysis to similarly quantify a latent blood Mn burden index. We then used an adjusted linear regression to estimate the Mn burden index with SWM measures. Interaction terms were used to estimate the modification effect by child sex for all models. Results showed that the between-errors-specific MMB mixture (i.e., this model demonstrates the impact of the MMB mixture on the between-error scores.) was associated (β = 6.50, 95% CI: 0.91, 12.08) with fewer between errors for boys and more between errors for girls. The strategy-specific MMB mixture (i.e., this model demonstrates the impact of the MMB mixture on the strategy scores) was associated (β = −1.36, 95% CI: 2.55, - 0.18) with less efficient strategy performance for boys and more efficient strategy performance for girls. A higher Mn burden index was associated (β = 0.86, 95% CI: 0.00, 1.72) with more between errors in the overall sample. The vulnerability to prenatal Mn biomarkers on SWM differs in the directionality by child sex. An MMB mixture and composite index of body burden are stronger predictors than a single biomarker for Mn exposure on WM performance. [Display omitted] • Associations between MMB mixture and SWMs differ in the directionality by child sex. • A higher Mn burden index was related to more between errors in the overall sample. • Mn exposure as an MMB is a stronger predictor than using a single biomarker. [ABSTRACT FROM AUTHOR]

Current evidence demonstrated that ambient fine particulate matter with an aerodynamic diameter ≤2.5 μm (PM 2.5) and its constituents may be obesogenic in children, but evidence from adults is lacking. Our aim was to characterize the association between PM 2.5 and its constituents and obesity in adults. We included 68,914 participants from the China Multi-Ethnic Cohort (CMEC) baseline survey. Three-year average concentrations of PM 2.5 and its constituents were evaluated by linking pollutant estimates to the geocoded residential addresses. Obesity was defined as body mass index (BMI) ≥ 28 kg/m2. Logistic regression was used to examine the relationship between PM 2.5 and its constituents and obesity. We performed weighed quantile sum (WQS) regression to get the overall effect of PM 2.5 and its constituents and the relative contribution of each constituent. Per-SD increase in PM 2.5 (odds ratio [OR] = 1.43, 95% confidence interval [CI]: 1.37–1.49), black carbon (BC) (1.42, 1.36–1.48), ammonium (1.43, 1.37–1.49), nitrate (1.44, 1.38–1.50), organic matter (OM) (1.45, 1.39–1.51), sulfate (1.42, 1.35–1.48), and soil particles (SOIL) (1.31, 1.27–1.36) were positively associated with obesity, and SS (0.60, 0.55–0.65) was negatively associated with obesity. The overall effect (OR = 1.34, 95% CI: 1.29–1.41) of the PM 2.5 and its constituents was positively associated with obesity, and ammonium made the most contribution to this relationship. Participants who were older, female, never smoked, lived in urban areas, had lower income or higher levels of physical activity were more significantly adversely affected by PM 2.5 , BC, ammonium, nitrate, OM, sulfate and SOIL compared to other individuals. Our study revealed that PM 2.5 constituents except SS were positively associated with obesity, and ammonium played the most important role. These findings provided new evidence for public health interventions, especially the precise prevention and control of obesity. [Display omitted] • Chemical constituents of PM 2.5 were positively related to obesity. • Ammonium played the most important role. • Effects were modified by age, sex, smoking, income, and physical activity. • Participants living in urban areas were more susceptible. [ABSTRACT FROM AUTHOR]

Hypertensive disorders in pregnancy (HDP) have heterogeneous etiologies. Previous studies have linked individual air pollutants to overall HDP with inconsistent results. Moreover, it has not been explored how exposure to a mixture of multiple air pollutants may affect the risks of the subtypes of the disorders. To investigate the associations of exposure to air pollutant mixture in the 1st and 2nd trimesters of pregnancy with the risks of HDP and its subtypes. Pregnancy data were obtained from the China Labor and Delivery Survey, a nationwide cross-sectional survey in 2015 and 2016. Levels of air pollutants [including fine particulate matter (PM 2.5), carbon monoxide (CO), nitrogen dioxide (NO 2), ozone (O 3), and sulfur dioxide (SO 2)] in the 1st and 2nd trimesters were estimated based on the model developed by the Institution of Atmospheric Physics, Chinese Academy of Science. Generalized linear mixed models were built to assess the single-exposure effects of air pollutants in early gestation on HDP. The restricted cubic spline function was further applied to assess the potential non-linearity. The weighted quantile sum (WQS) regression was used to investigate the effects of co-exposure to multiple air pollutants. A total of 67,512 pregnancies were included, and 2,834 were HDP cases. The single-effect analysis showed that CO, PM 2.5 , and SO 2 exposure in the 2nd trimester was positively associated with the risks of gestational hypertension (GH), with adjusted odds ratios (aORs) and 95% confidence intervals (CI) of 1.16 (1.04, 1.28), 1.19 (1.04, 1.37), and 1.13 (1.04, 1.22), respectively. The first-trimester O 3 exposure was also associated with an increased preeclampsia/eclampsia (PE) risk (aOR = 1.17; 95%CI: 1.02, 1.33). WQS regression confirmed positive associations of air pollutant mixture with HDP subtypes, with PM 2.5 as the main contributing pollutant to GH, and CO and O 3 as the main pollutants to PE. Exposure to multiple air pollutant mixtures in early pregnancy was associated with increased risks of hypertensive disorders in pregnancy. [ABSTRACT FROM AUTHOR]

Phosphorus (P) is a key limiting nutrient in subtropical forests and mixed forests with broadleaved species have been expected to stimulate P cycling, compared to pure conifer plantations. However, the mixture effect of Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) and broadleaved species on rhizosphere soil and coniferous tree P dynamics is unclear. In our study, eight plots of a single species of a Chinese fir plantation (pure plantation, PP) and eight mixed plantations (mixed plantation, MP) with broadleaved tree species (Michelia macclurei Dandy in Hunan Province or Schima superba Gardn. et Champ. in Fujian Province) were selected in subtropical China. Six P fractions in the rhizosphere and bulk soils were analyzed by a modified Hedley P fractionation method. Phosphorus fractions and nitrogen (N) concentrations in different root orders, different age fresh needles and twigs, and needle and twig litter of Chinese fir were measured. Our results showed that available P, slowly released P, occluded P, and the total extractable P in rhizosphere soil were significantly higher in MP than PP (p < 0.05). In contrast, P and N concentrations in the transportive roots and two-year old needles were generally higher in PP than MP. Meanwhile, the slowly released P, occluded P, total extractable P, and residual P in rhizosphere soil were negatively correlated with P concentrations in young (absorptive and transportive roots, one- and two-year old needles) but not old tissues (storative roots, three-year old needles and litters). In conclusion, mixture may increase soil P availability through the rhizosphere effect, but can decrease P and N concentration of Chinese fir tissues by competition between Chinese fir and broadleaved species. Clearly, the mixture effect may differ in soil and plant nutrients, and this issue needs be taken into consideration when converting a pure conifer plantation into a mixed-species forest.

Dielectric barrier discharge DBD-plasma based technologies have been widely investigated for the abatement of air pollutants. More recently, photocatalysis (TiO 2 /UV-lamp) has also showed promising results for air pollution abatement. In this work, these two methods were used separately and combined (TiO 2 /UV-lamp/DBD-plasma) in order to enhance the performance of the process for air pollutants degradation/mineralization. Ammonia (NH 3 ) and butyraldehyde (C 4 H 8 O) have been firstly treated alone and then an equimolar mixture (NH 3 /C 4 H 8 O) was monitored in a continuous reactor. Effect of operational parameters such as pollutants inlet concentration, flowrate, humidity and specific energy of plasma were thoroughly determined. Results showed that coupling both methods in the same reactor improves removal efficiency for single pollutant or a mixture of two pollutants. This processes combination showed a synergy between DBD-plasma and photocatalytic oxidation. Moreover, pollutant mineralization and potential intermediate byproducts have been characterized and discussed. Coupling both processes contributes to enhanced mineralization in comparison with DBD-plasma alone regarding the CO 2 selectivity. As for selectivity of byproducts: (i) Relative Humidity (RH), (ii) mixture effect and (iii) (TiO 2 /UV-lamp/DBD-plasma) combined processes inhibit ozone production during the pollutants removal/oxidation. [ABSTRACT FROM AUTHOR]