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Organophosphate ester and phthalate ester metabolites in urine from primiparas in Shenzhen, China: Implications for health risks Texte intégral
2019
Chen, Yi | Jiang, Lei | Lu, Shaoyou | Kang, Li | Luo, Xianru | Liu, Guihua | Cui, Xinyi | Yu, Yingxin
Organophosphate esters (OPEs) and phthalate esters (PAEs) are extensively used as additives in commercial and household products. However, knowledge on human exposure to OPEs and PAEs remains limited in China. This study aimed to investigate OPE and PAE metabolites in urine samples of primiparas and to evaluate the cumulative risk of OPE and PAE exposure. A total of 8 OPE metabolites and 11 PAE metabolites were measured in urine samples of 84 primiparas from Shenzhen, China. The OPE metabolites were found in at least 72% of the urine samples with bis(2-chloroethyl) phosphate (BCEP) being the dominant analogue. Among the 11 PAE metabolites, mono-n-butyl phthalate (mBP) was the most abundant analogue and had a median concentration (139 μg/L) greater than those reported in urine samples from other countries and regions. A significant, positive correlation was found between Σ₈OPEMs (the sum of 8 OPE metabolites) and body mass index (BMI). The urinary concentration of Σ₁₁PAEMs (the sum of 11 PAE metabolites) was positively associated with the time of computer using by the primiparas. The estimated daily intakes (EDI) of tris(2-chlorethyl) phosphate (TCEP, the parent chemical of BCEP) and di-n-butyl phthalate (DnBP, the parent chemical of mBP) were determined to be 0.47 and 9.14 μg/kg bw/day, respectively. The 95th percentile EDI values for TCEP and DnBP both exceeded their corresponding reference doses. Twelve and fifty-five percentage of the primiparas were estimated to have HIRfD (hazard index corresponding to reference doses) and HITDI (hazard index corresponding to tolerable daily intake) values exceeding 1 for OPEs and PAEs, respectively, suggesting a relatively high exposure risk.
Afficher plus [+] Moins [-]Microplastics in the environment: A critical review of current understanding and identification of future research needs Texte intégral
2019
Akdogan, Zeynep | Guven, Basak
Microplastics (plastic particles <5 mm) are a contaminant of increasing ecotoxicological concern in aquatic environments, as well as for human health. Although microplastic pollution is widespread across the land, water, and air, these environments are commonly considered independently; however, in reality are closely linked. This study aims to review the scientific literature related microplastic research in different environmental compartments and to identify the research gaps for the assessment of future research priorities. Over 200 papers involving microplastic pollution, published between 2006 and 2018, are identified in the Web of Science database. The original research articles in ‘Environmental Sciences’, ‘Marine/Freshwater Biology’, ‘Toxicology’, ‘Multidisciplinary Sciences’, ‘Environmental Studies’, ‘Oceanography’, ‘Limnology’ and ‘Ecology’ categories of Web of Science are selected to investigate microplastic research in seas, estuaries, rivers, lakes, soil and atmosphere. The papers identified for seas, estuaries, rivers and lakes are further classified according to (i) occurrence and characterization (ii) uptake by and effects in organisms, and (iii) fate and transport issues. The results reveal that whilst marine microplastics have received substantial scientific research, the extent of microplastic pollution in continental environments, such as rivers, lakes, soil and air, and environmental interactions, remains poorly understood.
Afficher plus [+] Moins [-]Tartaric acid-induced photoreductive dissolution of schwertmannite loaded with As(III) and the release of adsorbed As(III) Texte intégral
2019
Zhang, Jian | Li, Wei | Li, Ying | Zhou, Lixiang | Lan, Yeqing
Schwertmannite (SCH) has strong adsorption ability to As(III). However, there are few reports on the stability of SCH load with As(III) (SCH-As(III)). In this study, the effects of tartaric acid (TA), pH and coexisting ions including K+, Ca2+, Al3+ and CO32− on the photoreductive dissolution of SCH- As(III) and the release of the adsorbed As (III) were investigated. The results showed that under UV irradiation TA could greatly enhance the release of total Fe and total As from SCH-As(III). Nevertheless, the total Fe and total As in the solution decreased when TA was consumed up. Compared to SCH, the reductive dissolution of SCH-As(III) was obviously suppressed. In the dark, TA could slowly enhance the dissolution of SCH-As(III), but its effect on the release of adsorbed As(III) was weak. Low pH was conducive to the release of iron and arsenic. Ca2+, K+, and CO32− promoted the decrease of the dissolved total Fe in the later reaction. However, Al3+ inhibited the decrease of the dissolved total Fe and total As. The analyses of FTIR and XRD demonstrated that the mineralogical phase of SCH-As(III) after reaction changed. With light, the dissolved total Fe and total As existed mainly as Fe(II) and As(V), respectively. This is because Fe(II) was generated via ligand to metal charge transfer and As(III) was oxidized to As(V) by ·OH produced during the reaction. Thus, this study provides us with a comprehensive understanding of the stability of SCH-As(III) and the release of adsorbed As(III) in natural environments.
Afficher plus [+] Moins [-]An integrated approach using AHP and DEMATEL for evaluating climate change mitigation strategies of the Indian cement manufacturing industry Texte intégral
2019
Balsara, Sachin | Jain, Pramod Kumar | Ramesh, Anbanandam
Concrete, a cement-based product is the highest manufactured and second highest consumed product after water on earth. Across the world, production of cement is the most energy and emission intensive industry hence, the cement industry is currently under pressure to reduce greenhouse gases emissions (GHGEs). However, reducing the GHGEs of the cement industry especially for developing country like India is not an easy task. Cement manufacturing industry needs to focus on significant climate change mitigation strategies to reduce the GHGEs to sustain its production. This study aims at identifying significant climate change mitigation strategies of the cement manufacturing industry in the context of India. Extant literature review and expert opinion are used to identify climate change mitigation strategies of the cement manufacturing industry. In the present study, a model projects by applying both AHP and DEMATEL techniques to assess the climate change mitigation strategies of the cement industry. The AHP technique help in establishing the priorities of climate change mitigation strategies, while the DEMATEL technique forms the causal relationships among them. Through AHP, the results of this research demonstrate that Fuel emission reduction is on top most priority while the relative importance priority of the main remaining factors is Process emission reduction - Electric energy-related emission - Emission avoidance and reduction - Management mitigation measures. The findings also indicate that the main factors, Process emission reduction, and Fuel emission reduction are categorized in cause group factors, while the remaining factors, Electric energy-related emission, Emission avoidance and reduction and Management mitigation measures are in effect group factors. Present model will help supply chain analysts to develop both short-term and long-term decisive measures for effectively managing and reducing GHGEs.
Afficher plus [+] Moins [-]Prenatal aluminum exposure is associated with increased newborn mitochondrial DNA copy number Texte intégral
2019
Liu, Bingqing | Song, Lulu | Zhang, Lina | Wu, Mingyang | Wang, Lulin | Cao, Zhongqiang | Zhang, Bin | Xu, Shunqing | Wang, Youjie
Aluminum is a widely distributed metal that has been reported to have embryotoxicity and fetotoxicity in animal studies. However, there has been no study of the association between prenatal aluminum exposure and newborn mitochondrial DNA copy number (mtDNAcn). We aimed to investigate the effect of prenatal aluminum exposure on newborn mtDNAcn. A total of 762 mother-newborn pairs were recruited between November 2013 and March 2015 in Wuhan city, China. We measured maternal urinary aluminum concentrations at three trimesters of pregnancy. Relative mtDNAcn was measured in DNA extracted from umbilical cord blood samples. We used generalized estimating equations to assess the relationship between prenatal aluminum exposure and newborn mtDNAcn. The geometric means of creatinine corrected aluminum concentrations were 31.0 μg/g Cr (95% CI: 27.6, 34.7), 40.9 μg/g Cr (95% CI: 35.7, 46.8) and 58.4 μg/g Cr (95% CI: 51.2, 67.4) for the first, second and third trimesters, respectively. After adjustment for potential confounding factors, a doubling of maternal urinary aluminum concentrations during the second and third trimesters was related to 3.16% (95% CI: 0.88, 5.49) and 4.20% (95% CI: 1.64, 6.81) increases in newborn mtDNAcn, respectively, while the association between maternal urinary aluminum concentration during the first trimester and newborn mtDNAcn was not significant (percent difference: 0.70%, 95% CI: −2.25, 3.73). Prenatal aluminum exposure during the second and third trimesters was positively associated with newborn mtDNAcn. Further studies are essential to elucidate on the potential health consequences of newborn mtDNAcn.
Afficher plus [+] Moins [-]Enhancement of aqueous sulfate formation by the coexistence of NO2/NH3 under high ionic strengths in aerosol water Texte intégral
2019
Chen, Tianzeng | Chu, Biwu | Ge, Yanli | Zhang, Shuping | Ma, Qingxin | He, Hong | Li, Shao-Meng
Current air quality models usually underestimate the concentration of ambient air sulfate, but the cause of this underestimation remains unclear. One reason for the underestimation is that the sulfate formation mechanism in the models is incomplete, and does not adequately consider the impact of the synergistic effects of high concentrations of multiple pollutants on sulfate formation. In this work, the roles of gaseous NO₂, NH₃ and solution ionic strength in the formation of sulfate in the aqueous phase were quantitatively investigated using a glass reactor and a 30 m³ smog chamber, separately. The results showed that sulfate formation was enhanced to different degrees in the presence of gas-phase NO₂, NH₃ and their coexistence as solutes in both liquid solution and aerosol water. NH₃ enhances the aqueous oxidation of SO₂ by NO₂ mainly by accelerating the uptake of SO₂ through increased solubility. More importantly, we found that high ionic strength in aerosol water could significantly accelerate the aqueous oxidation of SO₂, resulting in unexpectedly high S(VI) formation rates. We estimate that under severe haze conditions, heterogeneous oxidation of SO₂ by NO₂ on aerosols may be much shorter than that through gas phase oxidation by OH, aided by high ionic strengths in aerosols. Considering the existence of complex air pollution conditions with high concentrations of NO₂, NH₃ and aerosol water, as expected in typical urban and suburban settings, the sulfate formation mechanisms revealed in the present work should be incorporated into air quality models to improve the prediction of sulfate concentrations.
Afficher plus [+] Moins [-]Association between urinary concentration of phthalate metabolites and impaired renal function in Shanghai adults Texte intégral
2019
Chen, Jingsi | Zhou, Xiaofeng | Zhang, Han | Liu, Yueming | Cao, Chen | Dong, Ruihua | Yuan, Yaqun | Wang, Min | Lu, Yuanan | Wu, Min | Li, Shuguang | Chen, Bo
Exposure to phthalates is reported to be associated with increased incidence of microalbuminuria and low-grade albuminuria in children and adolescents. However, this phenomenon of phthalate-related nephrotoxicity is unknown in adults.Urine samples of 1663 adults from the 2012 Shanghai Food Consumption Survey (SHFCS) were measured for 10 metabolites of 6 phthalates and for renal function parameters. Their associations were explored by linear and logistic regression models.Multivariate linear regression analysis showed that all three renal function parameters (albumin-to-creatinine ratio (ACR), β2-microglobulin (B2M), and N-acetyl-β-d-glucosaminidase (NAG)) are positively associated with six metabolites, including mono-benzylphthalate (MBzP), mono-2-ethylhexylphthalate (MEHP), mono-2-ethyl-5-oxohexyphthalate (MEOHP), mono-2-ethyl-5-hydroxyhexylphthalate (MEHHP), mono-2-ethyl-5-carboxypentylphthalate (MECPP), and mono-2-carboxymethyl-hexyl phthalate (MCMHP) (P < 0.05). Logistic analysis showed that the prevalence of hyperALBuria, hyperB2Muria, hyperNAGuria, or potentially impaired renal function (PIRF) were positively associated with urinary levels of MBzP, MEOHP, and MECPP, respectively (P < 0.05). Co-exposure to identified risk metabolites monoethylphthalate (MEP), MBzP, MEHP, MEOHP, MECPP, MEHHP, and MCMHP increased the risk of having impaired renal function.Certain metabolites of phthalates, including bis (2-ethylhexyl) phthalate (DEHP) and benzyle butyl phthalate (BBzP), were associated with impaired renal function in Shanghai adults.
Afficher plus [+] Moins [-]Adaptive shifts of bacterioplankton communities in response to nitrogen enrichment in a highly polluted river Texte intégral
2019
Yang, Yuzhan | Gao, Yangchun | Huang, Xuena | Ni, Ping | Wu, Yueni | Deng, Ye | Zhan, Aibin
Anthropogenic activity-mediated nutrient pollution, especially nitrogen enrichment, poses one of the major threats to river ecosystems. However, it remains unclear how and to which extent it affects aquatic microbial communities, especially in heavily polluted rivers. In this study, a significant environmental gradient, particularly nitrogen gradient, was observed along a wastewater receiving river, the North Canal River (NCR). The pollution level was highest, moderate, and lowest in the up-, middle, and down-streams, respectively. The community composition of bacterioplankton transitioned from being Betaproteobacteria-dominated upstream to Gammaproteobacteria-dominated downstream. Copiotrophic groups, such as Polynucleobacter (Betaproteobacteria) and Hydrogenophaga (Betaproteobacteria), were dominant in the upstream. Multiple statistical analyses indicated that total nitrogen (TN) was the most important factor driving the adaptive shifts of community structure. Analyses of co-occurrence networks showed that the complexity of networks was disrupted in the up- and middle streams, while enhanced in the downstream. Our findings here suggested that microbial interactions were reduced in response to the aggravation of nutrient pollution. Similar to these changes, we observed significant dissimilarity of composition of functional groups, with highest abundance of nitrogen metabolism members under the highest level of nitrogen enrichment. Further analyses indicated that most of these functional groups belonged to Betaproteobacteria, suggesting the potential coupling of community composition and function diversity. In summary, adaptive shifts of bacterioplankton community composition, as well as species interactions, occurred in response to nutrient pollution in highly polluted water bodies.
Afficher plus [+] Moins [-]Investigation of emission characteristics of NMVOCs over urban site of western India Texte intégral
2019
Yadav, Ravi | Sahu, L.K. | Tripathi, Nidhi | Pal, D. | Beig, G. | Jaaffrey, S.N.A.
This is the first study to characterize the variation and emission of C₂-C₅ non-methane volatile organic compounds (NMVOCs) in a semi-urban site of western India based on measurements during February–December 2015. Anthropogenic NMVOCs show clear seasonal dependence with highest in winter and lowest in monsoon season. Biogenic NMVOCs likes isoprene show highest mixing ratios in the pre-monsoon season. The diurnal variation of NMVOC species can be described by elevated values from night till morning and lower values in the afternoon hours. The elevated levels of NMVOCs during night and early morning hours were caused mainly by weaker winds, temperature inversion and reduced chemical loss. The correlations between NMVOCs, CO and NOx indicate the dominant role of various local emission sources. Use and leakage of liquefied petroleum gas (LPG) contributed to the elevated levels of propane and butanes. Mixing ratios of ethylene, propylene, CO, NOx, etc. show predominant emissions from combustion of fuels in automobiles and industries. The Positive Matrix Factorization (PMF) source apportionments were performed for the seven major emission sectors (i.e. Vehicular exhaust, Mixed industrial emissions, Biomass/Fired brick kilns/Bio-fuel, Petrochem, LPG, Gas evaporation, Biogenic). Emissions from vehicle exhaust and industry-related sources contributed to about 19% and 40% of the NMVOCs, respectively. And the rest (41%) was attributed to the emissions from biogenic sources, LPG, gasoline evaporation and biomass burning. Diurnal and seasonal variations of NMVOCs were controlled by local emissions, meteorology, OH concentrations, long-range transport and planetary boundary layer height. This study provides a good reference for framing environmental policies to improve the air quality in western region of India.
Afficher plus [+] Moins [-]Environmental risks associated with contaminants of legacy and emerging concern at European aquaculture areas Texte intégral
2019
Aminot, Yann | Sayfritz, Stephen J. | Thomas, Kevin V. | Godinho, Lia | Botteon, Elena | Ferrari, Federico | Boti, Vasiliki | Albanis, Triantafyllos | Köck-Schulmeyer, Marianne | Díaz-Cruz, M. Silvia | Farré, Marinella | Barceló, Damià | Marques, António | Readman, James W.
Environmental risks associated with contaminants of legacy and emerging concern at European aquaculture areas Texte intégral
2019
Aminot, Yann | Sayfritz, Stephen J. | Thomas, Kevin V. | Godinho, Lia | Botteon, Elena | Ferrari, Federico | Boti, Vasiliki | Albanis, Triantafyllos | Köck-Schulmeyer, Marianne | Díaz-Cruz, M. Silvia | Farré, Marinella | Barceló, Damià | Marques, António | Readman, James W.
The contamination of marine ecosystems by contaminants of emerging concern such as personal care products or per- and polyfluoroalkyl substances is of increasing concern. This work assessed the concentrations of selected contaminants of emerging concern in water and sediment of European aquaculture areas, to evaluate their co-variation with legacy contaminants (polycyclic aromatic hydrocarbons) and faecal biomarkers, and estimate the risks associated with their occurrence. The 9 study sites were selected in 7 European countries to be representative of the aquaculture activities of their region: 4 sites in the Atlantic Ocean and 5 in the Mediterranean Sea. Musks, UV filters, preservatives, per- and polyfluoroalkyl substances and polycyclic aromatic hydrocarbons were detected in at least one of the sites with regional differences. While personal care products appear to be the main component of the water contamination, polycyclic aromatic hydrocarbons were mostly found in sediments. As expected, generally higher levels of personal care products were found in sewage impacted sites, urbanised coasts and estuaries. The risk assessment for water and sediment revealed a potential risk for the local aquatic environment from contaminants of both legacy and emerging concern, with a significant contribution of the UV filter octocrylene. Despite marginal contributions of per- and polyfluoroalkyl substances to the total concentrations, PFOS (perfluorooctane sulfonate) aqueous concentrations combined to its low ecotoxicity thresholds produced significant hazard quotients indicating a potential risk to the ecosystems.
Afficher plus [+] Moins [-]Environmental risks associated with contaminants of legacy and emerging concern at European aquaculture areas Texte intégral
2019
Aminot, Yann | Sayfritz, Stephen J. | Thomas, Kevin V. | Godinho, Lia | Botteon, Elena | Ferrari, Federico | Boti, Vasiliki | Albanis, Triantafyllos | Köck-schulmeyer, Marianne | Diaz-cruz, Silvia | Farré, Marinella | Barceló, Damià | Marques, António | Readman, James W.
The contamination of marine ecosystems by contaminants of emerging concern such as personal care products or per- and polyfluoroalkyl substances is of increasing concern. This work assessed the concentrations of selected contaminants of emerging concern in water and sediment of European aquaculture areas, to evaluate their co-variation with legacy contaminants (polycyclic aromatic hydrocarbons) and faecal biomarkers, and estimate the risks associated with their occurrence. The 9 study sites were selected in 7 European countries to be representative of the aquaculture activities of their region: 4 sites in the Atlantic Ocean and 5 in the Mediterranean Sea. Musks, UV filters, preservatives, per- and polyfluoroalkyl substances and polycyclic aromatic hydrocarbons were detected in at least one of the sites with regional differences. While personal care products appear to be the main component of the water contamination, polycyclic aromatic hydrocarbons were mostly found in sediments. As expected, generally higher levels of personal care products were found in sewage impacted sites, urbanised coasts and estuaries. The risk assessment for water and sediment revealed a potential risk for the local aquatic environment from contaminants of both legacy and emerging concern, with a significant contribution of the UV filter octocrylene. Despite marginal contributions of per- and polyfluoroalkyl substances to the total concentrations, PFOS (perfluorooctane sulfonate) aqueous concentrations combined to its low ecotoxicity thresholds produced significant hazard quotients indicating a potential risk to the ecosystems.
Afficher plus [+] Moins [-]Environmental risks associated with contaminants of legacy and emerging concern at European aquaculture areas Texte intégral
2019
Aminot, Yann | Sayfritz, Stephen J. | Thomas, Kevin V. | Godinho, Lia | Botteon, Elena | Ferrari, Federico | Boti, Vasiliki | Albanis, Triantafyllos | Köck-Schulmeyer, Marianne | Diaz-Cruz, Silvia | Farré, Marinella | Barceló, Damià | Marques, Antonio | Readman, James W. | European Commission | Diaz-Cruz, M. Silvia [0000-0003-3331-4076] | Barceló, Damià [0000-0002-8873-0491] | Consejo Superior de Investigaciones Científicas [https://ror.org/02gfc7t72]
The contamination of marine ecosystems by contaminants of emerging concern such as personal care products or per- and polyfluoroalkyl substances is of increasing concern. This work assessed the concentrations of selected contaminants of emerging concern in water and sediment of European aquaculture areas, to evaluate their co-variation with legacy contaminants (polycyclic aromatic hydrocarbons) and faecal biomarkers, and estimate the risks associated with their occurrence. The 9 study sites were selected in 7 European countries to be representative of the aquaculture activities of their region: 4 sites in the Atlantic Ocean and 5 in the Mediterranean Sea. Musks, UV filters, preservatives, per- and polyfluoroalkyl substances and polycyclic aromatic hydrocarbons were detected in at least one of the sites with regional differences. While personal care products appear to be the main component of the water contamination, polycyclic aromatic hydrocarbons were mostly found in sediments. As expected, generally higher levels of personal care products were found in sewage impacted sites, urbanised coasts and estuaries. The risk assessment for water and sediment revealed a potential risk for the local aquatic environment from contaminants of both legacy and emerging concern, with a significant contribution of the UV filter octocrylene. Despite marginal contributions of per- and polyfluoroalkyl substances to the total concentrations, PFOS (perfluorooctane sulfonate) aqueous concentrations combined to its low ecotoxicity thresholds produced significant hazard quotients indicating a potential risk to the ecosystems. | This study was financially supported by the SEA-on-a-CHIP project, funded from European Union Seventh Framework Programme (FP7-OCEAN-2013) under grant agreement No. 614168. Antonio Marques is supported through the FCT Investigator program (IF). | Peer reviewed
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