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Race-specific associations of urinary phenols and parabens with adipokines in midlife women: The Study of Women's Health Across the Nation (SWAN) Full text
2022
Lee, Seulbi | Karvonen-Gutierrez, Carrie | Mukherjee, Bhramar | Herman, William H. | Park, Sung Kyun
Adipokines, cytokines secreted by adipose tissue, may contribute to obesity-related metabolic disease. The role of environmental phenols and parabens in racial difference in metabolic disease burden has been suggested, but there is limited evidence. We examined the cross-sectional associations of urinary phenols and parabens with adipokines and effect modification by race. Urinary concentrations of 6 phenols (bisphenol-A, bisphenol-F, 2,4-diclorophenol, 2,5-diclorophenol, triclosan, benzophenone-3) and 4 parabens (methyl-paraben, ethyl-paraben, propyl-paraben, butyl-paraben) were measured in 2002–2003 among 1200 women (mean age = 52.6) enrolled in the Study of Women's Health Across the Nation Multi-Pollutant Study. Serum adipokines included adiponectin, high molecular weight (HMW)-adiponectin, leptin, soluble leptin receptor (sOB-R). Linear regression models were used to estimate the adjusted percentage change in adipokines per inter-quantile range (IQR) increase in standardized and log-transformed levels of individual urinary phenols and parabens. Bayesian kernel machine regression (BKMR) was used to evaluate the joint effect of urinary phenols and parabens as mixtures. Participants included white (52.5%), black (19.3%), and Asian (28.1%) women. Urinary 2,4-dichlorophenol was associated with 6.02% (95% CI: 1.20%, 10.83%) higher HMW-adiponectin and urinary bisphenol-F was associated with 2.60% (0.48%, 4.71%) higher sOB-R. Urinary methyl-paraben was associated with lower leptin in all women but this association differed by race: 8.58% (−13.99%, −3.18%) lower leptin in white women but 11.68% (3.52%, 19.84%) higher leptin in black women (P interaction = 0.001). No significant associations were observed in Asian women. Additionally, we observed a significant positive overall effect of urinary phenols and parabens mixtures in relation to leptin levels in black, but not in white or Asian women. Urinary bisphenol-F, 2,4-dichlorophenol and methyl-paraben may be associated with favorable profiles of adipokines, but methyl-paraben, widely used in hair and personal care products, was associated with unfavorable leptin levels in black women. Future studies are needed to confirm this racial difference.
Show more [+] Less [-]Bioaccumulation of per- and polyfluoroalkyl substance in fish from an urban river: Occurrence, patterns and investigation of potential ecological drivers Full text
2022
Macorps, Nicolas | Le Menach, Karyn | Pardon, Patrick | Guérin-Rechdaoui, Sabrina | Rocher, Vincent | Budzinski, Hélène | Labadie, Pierre
Per- and polyfluoroalkyl substances (PFAS) are ubiquitous in aquatic environments and a recent shift toward emerging PFAS is calling for new data on their occurrence and fate. In particular, understanding the determinants of their bioaccumulation is fundamental for risk assessment purposes. However, very few studies have addressed the combined influence of potential ecological drivers of PFAS bioaccumulation in fish such as age, sex or trophic ecology. Thus, this work aimed to fill these knowledge gaps by performing a field study in the Seine River basin (France). Composite sediment and fish (European chub, Squalius Cephalus) samples were collected from four sites along a longitudinal transect to investigate the occurrence of 36 PFAS. Sediment molecular patterns were dominated by fluorotelomer sulfonamidoalkyl betaines (i.e. 6:2 and 8:2 FTAB, 46% of ∑PFAS on average), highlighting the non-negligible contribution of PFAS of emerging concern. C₉–C₁₄ perfluoroalkyl carboxylic acids, perfluorooctane sulfonic acid (PFOS), perfluorooctane sulfonamide (FOSA) and 10:2 fluorotelomer sulfonate (10:2 FTSA) were detected in all fish samples. Conversely, 8:2 FTAB was detected in a few fish from the furthest downstream station only, suggesting the low bioaccessibility or the biotransformation of FTABs. ∑PFAS in fish was in the range 0.22–3.8 ng g⁻¹ wet weight (ww) and 11–140 ng g⁻¹ ww for muscle and liver, respectively. Fish collected upstream of Paris were significantly less contaminated than those collected downstream, pointing to urban and industrial inputs. The influence of trophic ecology and biometry on the interindividual variability of PFAS burden in fish was examined through analyses of covariance (ANCOVAs), with sampling site considered as a categorical variable. While the latter was highly significant, diet was also influential; carbon sources and trophic level (i.e. estimated using C and N stable isotope ratios, respectively) equally explained the variability of PFAS levels in fish.
Show more [+] Less [-]Mercury can be transported into marine copepod by polystyrene nanoplastics but is not bioaccumulated: An increased risk? Full text
2022
Xie, Dongmei | Wei, Hui | Lee, Jae-seong | Wang, Minghua
Plastic pollution is a serious problem in the global marine environment because it can produce negative effects at the biological and ecological levels. Due to large surface-area-to-volume ratio and inherent hydrophobicity, nanoplastics can serve as carriers of contaminants, and may affect their fate and toxicity in marine environments. However, the combined effects of nanoplastics and mercury (Hg) in marine organisms have not been well characterized. In this study, after verifying the ingestion of polystyrene nano-size plastics (PS NPs, 50 nm) by the copepod Tigriopus japonicus and adsorption of Hg to PS NPs, we investigated the effects of PS NPs and Hg exposure (alone or in combination) for 48 h on the copepods. Specifically, a 72-h depuration was performed after 48 h exposure. The results showed that after 48 h exposure, the copepod's Hg concentration was significantly increased in the combined exposure group compared to that in the Hg treatment group, but these differences did not persist following 24 h of depuration. Therefore, PS NPs transported Hg into the copepods but did not promote Hg bioaccumulation. Treatment with PS NPs alone did not induce toxicity in T. japonicus, but co-exposure to PS NPs and Hg resulted in elevated transcription of genes related to energy production, antioxidant response, and detoxification/stress defense when compared with Hg treatment alone, demonstrating the synergistic interaction between PS NPs and Hg. Our findings contribute to a comprehensive understanding about the combined toxicity of nanoplastics and metals and the potential ecological risks of associated with these effects in marine environments.
Show more [+] Less [-]Yielding hydroxyl radicals in the Fenton-like reaction induced by manganese (II) oxidation determines Cd mobilization upon soil aeration in paddy soil systems Full text
2022
Wang, Meng | Liu, Yongbing | Shi, Huading | Li, Shanshan | Chen, Shibao
As a redox-sensitive element, manganese (Mn) plays a critical role in Cd mobilization, especially in paddy soil. In an anoxic environment, the precipitation of Mn(II)-hydroxides specifically favors Cd retention, while draining the paddy fields results in substantial remobilization of Cd. However, how the change in Mn redox states during the periodical transit of anoxic to oxic systems affects Cd mobility remains unclear. In this study, we demonstrate that the radical effect generated during the oxidation of Mn(II)-hydroxides exerts a significant effect on the oxidative dissolution of Cd during the aeration of paddy soils. The extractable Cd concentration decreased rapidly during the reduction phases but increased upon oxidation, while Cd availability produced the opposite effect with soil pe + pH and the extractable Mn concentration. Inhibiting the oxidation of Mn(II)-containing phases by microbes suppressed the production of hydroxyl free radicals (•OH) and Cd mobilization in the drainage phase. Analysis of X-ray absorption spectroscopy and sequential extraction demonstrated that the transformation from the Mn phase of Mn(II) to Mn(III/IV) determines Cd solubility. Altogether, the oxidization of Mn(II)-hydroxides was associated with the generation of significant amounts of •OH. The dissolution of Mn(II)- incorporating phases lead to a net release of Cd into soils during soil aeration.
Show more [+] Less [-]Microbial interactions enhanced environmental fitness and expanded ecological niches under dibutyl phthalate and cadmium co-contamination Full text
2022
Wang, Xuejun | Wu, Hao | Dai, Chuhan | Wang, Xiaoyu | Wang, Lvjing | Xu, Jianming | Lu, Zhenmei
Co-contamination of organic pollutants and heavy metals is universal in the natural environment. Dibutyl phthalate (DBP), a typical plasticizer, frequently coexists with cadmium (Cd) in nature. However, little attention has been given to the impacts of co-contamination by DBP and Cd on microbial communities or the responses of microbes. To address this, a microcosm experiment was conducted by supplying the exogenous DBP-degrading bacterium Glutamicibacter nicotianae ZM05 to investigate the interplay among DBP-Cd co-contamination, the exogenous DBP-degrading bacterium G. nicotianae ZM05, and indigenous microorganisms. To adapt to co-contamination stress, microbial communities adjust their diversity, interactions, and functions. The stability of the microbial community decreased under co-contamination, as evidenced by lower diversity, simpler network, and fewer ecological niches. Microbial interactions were strengthened, as evidenced by enriched pathways related to microbial communications. Meanwhile, interactions between microorganisms enhanced the environmental fitness of the exogenous DBP-degrading bacterium ZM05. Based on co-occurrence network prediction and coculture experiments, metabolic interactions between the non-DBP-degrading bacterium Cupriavidus metallidurans ZM16 and ZM05 were proven. Strain ZM16 utilized protocatechuic acid, a DBP downstream metabolite, to relieve acid inhibition and adsorbed Cd to relieve toxic stress. These findings help to explain the responses of bacterial and fungal communities to DBP-Cd co-contamination and provide new insights for the construction of degrading consortia for bioremediation.
Show more [+] Less [-]Biomedical and catalytic applications of agri-based biosynthesized silver nanoparticles Full text
2022
Garg, Rajni | Rani, Priya | Garg, Rishav | Khan, Mohammad Amir | Khan, Nadeem Ahmad | Khan, Afzal Husain | Américo-Pinheiro, Juliana Heloisa Pinê
Nanotechnology has been recognized as the emerging field for the synthesis, designing, and manipulation of particle structure at the nanoscale. Its rapid development is also expected to revolutionize industries such as applied physics, mechanics, chemistry, and electronics engineering with suitably tailoring various nanomaterials. Inorganic nanoparticles such as silver nanoparticles (Ag-NPs) have garnered more interest with their diverse applications. In correspondence to green chemistry, researchers prioritize green synthetic techniques over conventional ones due to their eco-friendly and sustainable potential. Green-synthesized NPs have proven more beneficial than those synthesized by conventional methods because of capping by secondary metabolites. The present study reviews the various means being used by the researchers for the green synthesis of Ag-NPs. The morphological characteristics of these NPs as obtained from numerous characterization techniques have been explored. The potential applications of bio-synthesized Ag-NPs viz. Antimicrobial, antioxidant, catalytic, and water remediation along with the plausible mechanisms have been discussed. In addition, toxicity analysis and biomedical applications of these NPs have also been reviewed to provide a detailed overview. The study signifies that biosynthesized Ag-NPs can be efficiently used for various applications in the biomedical and industrial sectors as an environment-friendly and efficient tool.
Show more [+] Less [-]Sensitive inflammatory biomarkers of acute fine particulate matter exposure among healthy young adults: Findings from a randomized, double-blind crossover trial on air filtration Full text
2022
Wen, Fuyuan | Huang, Jing | Sun, Yanyan | Zhao, Yan | Li, Bingxiao | Wu, Ziyuan | Zhang, Ling
The short-term alteration of peripheral cytokines may be an early adverse health effect of PM₂.₅ exposure and may be further associated with cardiovascular disease. We conducted a randomized, double-blind crossover trial using true or sham air filtration among 54 healthy college students in Beijing to investigate the potential benefits of short-term indoor air filtration and the adverse health effects of time-weighted personal PM₂.₅ exposure through inflammatory cytokines. The participants randomly received true or sham air filtration intervention for a week, and the treatment was changed after a two-week washout period. Peripheral blood samples were collected after each intervention period to measure 38 inflammatory cytokines. A linear mixed-effects model was applied to estimate the impacts of air purification or a 10 μg/m³ PM₂.₅ exposure increase on cytokines. Lag effects of PM₂.₅ exposure were analyzed using single-day and moving average lag models. Air filtration reduced indoor and time-weighted average personal PM₂.₅ concentrations by 69.0% (from 33.6 to 10.4 μg/m³) and 40.3% (from 40.6 to 24.3 μg/m³), respectively. We observed a significant association of PM₂.₅ exposure with growth-regulated alpha protein (GRO-α) of −11.3% (95%CI: 17.0%, −5.4%). In the lag models, significant associations between personal PM₂.₅ exposure and interleukin-1 receptor antagonist (IL-1Ra), monocyte chemotactic protein (MCP-1), and eotaxin were obtained at lag0, while associations with cytokines including vascular endothelial growth factor (VEGF), epidermal growth factor (EGF), fibroblast growth factor-2 (FGF-2), granulocyte colony-stimulating factor (G-CSF), macrophage inflammatory protein-1β (MIP-1β), IL-4, tumor necrosis factor-α (TNF-α), and interferon-γ (IFN-γ) were noted at relatively long lagged exposure windows (lag5-lag6). No significant alteration in cytokines was observed under true air filtration intervention. Our study indicates the effectiveness of air filtration on indoor PM₂.₅ reduction. PM₂.₅ exposure may decrease GRO-α levels and change different cytokine levels time-varyingly. Further study is still needed to explore the mechanisms of PM₂.₅ exposure on the inflammatory response.
Show more [+] Less [-]Leaching of PBDEs from microplastics under simulated gut conditions: Chemical diffusion and bioaccumulation Full text
2022
Sun, Bingbing | Zeng, E. Y. (Eddy Y.)
Considerable efforts on exposure assessment of microplastics (MPs) as an agent in transport of toxic contaminants have been performed in organisms. However, chemical diffusion of inherent hydrophobic organic contaminants from MPs under simulated gut conditions is poorly examined. The present study examined the transfer kinetics of polybrominated diphenyl ethers (PBDEs) from polystyrene (PS), acrylonitrile butadiene styrene (ABS), and polypropylene (PP) MPs under gut surfactants (sodium taurocholate) at two relevant body temperatures of marine organisms, and evaluated the importance of MP ingestion in bioaccumulation of PBDEs in lugworm by a biodynamic model. Diffusion coefficients of PBDEs range from 5.82 × 10⁻²³ to 7.96 × 10⁻²⁰ m² s⁻¹ in PS, 5.49 × 10⁻²³ to 3.45 × 10⁻²⁰ m² s⁻¹ in ABS, and 5.58 × 10⁻²¹ to 5.79 × 10⁻¹⁷ m² s⁻¹ in PP, with apparent activation energies in the range of 33–148 kJ mol⁻¹. The biota–plastic accumulation factors of PBDEs leached from these plastics range from 1.44 × 10⁻⁸ to 7.15 × 10⁻⁵. Although ingestion of MPs with the common size (>0.5 mm) showed the negligible contribution to bioaccumulation of PBDEs in lugworm, their contribution in PBDEs transfer can be increased with gradual breakdown of MPs.
Show more [+] Less [-]Facile nanoplastics formation from macro and microplastics in aqueous media Full text
2022
Peller, Julie R. | Mezyk, Stephen P. | Shidler, Sarah | Castleman, Joe | Kaiser, Scott | Faulkner, Richard F. | Pilgrim, Corey D. | Wilson, Antigone | Martens, Sydney | Horne, Gregory P.
The immense production of plastic polymers combined with their discordancy with nature has led to vast plastic waste contamination across the geosphere, from the oceans to freshwater reservoirs, wetlands, remote snowpacks, sediments, air and multiple other environments. These environmental pollutants include microplastics (MP), typically defined as small and fragmented plastics less than 5 mm in size, and nanoplastics (NP), particles smaller than a micrometer. The formation of micro and nanoplastics in aqueous media to date has been largely attributed to fragmentation of plastics by natural (i.e., abrasion, photolysis, biotic) or industrial processes. We present a novel method to create small microplastics (≲ 5 μm) and nanoplastics in water from a wide variety of plastic materials using a small volume of a solubilizer liquid, such as n-dodecane, in combination with vigorous mixing. When the suspensions or solutions are subjected to ultrasonic mixing, the particle sizes decrease. Small micro- and nanoparticles were made from commercial, real world and waste (aged) polyethylene, polystyrene, polycarbonate and polyethylene terephthalate, in addition to other plastic materials and were analyzed using dark field microscopy, Raman spectroscopy and particle size measurements. The presented method provides a new and simple way to create specific size distributions of micro- and nanoparticles, which will enable expanded research on these plastic particles in water, especially those made from real world and aged plastics. The ease of NP and small MP formation upon initial mixing simulates real world environments, thereby providing further insight into the behavior of plastics in natural settings.
Show more [+] Less [-]Comprehensive efficiency evaluation of wastewater treatment plants in northeast Qinghai–Tibet Plateau using slack–based data envelopment analysis Full text
2022
Feng, Zhaohui | Liu, Xiaojie | Wang, Lingqing | Wang, Yong | Yang, Jun | Wang, Yazhu | Huan, Yizhong | Liang, Tao | Yu, Qiming Jimmy
Comprehensive efficiency analysis of wastewater treatment plants (WWPTs) in the alpine region with harsh environment and poor techniques as well as managing experience could provide targeted and effective improvement evidences for local wastewater treatment industry and help to improve the water quality of downstream reaches. In this paper, slack–based data envelopment analysis (SBM–DEA) was adopted to assess the operating efficiencies of WWPTs in northeast Qinghai–Tibet Plateau (QTP). Results showed that the average efficiency score for all WWPTs was 0.608, and 32.5% of WWPTs were efficient. Some WWPTs had large improvement potentials in operating costs and pollutant removal rates. Lowering expenditures and promoting facility construction for WWPTs to overcome the climate difficulties and improve management level was necessary according to their improvement potentials. In addition, the relative importance of the quantitative influential factors to efficiencies scores calculated by random forest regression (RFR) indicated that design capacity and temperature were important quantitative factors affecting the performance of WWPTs. Furthermore, geographical location and design capacity also had significant influence on the comprehensive efficiency of WWPTs verified by Kruskal–Wallis test. Our results highlight the importance of facilities upgrading, scientific management for WWPTs. And the relative improvement suggestions on overcoming the high and cold environment should also be considered for the efficient operations of WWTPs as well as the protection the aquatic environment.
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