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Public health benefits of optimizing urban industrial land layout - The case of Changsha, China النص الكامل
2020
Xu, Wanjun | Zeng, Zhuotong | Xu, Zhengyong | Li, Xiaodong | Chen, Xuwu | Li, Xin | Xiao, Rong | Liang, Jie | Chen, Gaojie | Lin, Anqi | Li, Jinjin | Zeng, Guangming
In China, ambient fine particulate matter (PM₂.₅) causes a large health burden and raises specific concerns for policymakers. However, assessments of the health effects associated with air pollution from industrial land layouts remain inadequate. This study established a comprehensive assessment framework to quantify the health and economic impacts of PM₂.₅ exposure at different industrial geographical locations. This framework aims to optimize the spatial distribution of industrial emissions to achieve the lowest public health costs in Changsha, a representative industrial city in China. Health effects were estimated by applying the integrated exposure-response model and a long-range pollution dispersion model (CALPUFF). The value of statistical life (VSL) was used to monetize health outcomes. It was found that implementing an optimal industrial land layout can yield considerable social and financial benefits. Compared with the current industrial space layout, in 2030, the averted contribution by Changsha’s industrial sector to PM₂.₅-related mortality and corresponding economic losses will be 60.8% and 0.69 billion US dollars (USD), respectively. The results of optimization analyses highlighted that population density and emission location are significant factors affecting the health burden. This method can identify the optimal geographical allocation of industrial land with minimal expected health and economic burden. These results will also provide policymakers with a measurable assessment of health risks related to industrial spatial planning and the associated health costs to enhance the effectiveness of efforts to improve air quality.
اظهر المزيد [+] اقل [-]Estimating historical [formula omitted] exposures for three decades (1987–2016) in Japan using measurements of associated air pollutants and land use regression النص الكامل
2020
Araki, Shin | Shima, Masayuki | Yamamoto, Kouhei
Accurate estimation of historical PM2.5 exposures for epidemiological studies is challenging when extensive monitoring data are limited in duration. Here, we develop a national-scale PM2.5 exposure model for Japan using measurements recorded between 2014 and 2016 to estimate monthly means for 1987 through 2016. Our objective is to obtain accurate PM2.5 estimates for years prior to implementation of extensive PM2.5 monitoring, using observations from a limited period. We utilize a neural network to convey the non-linear relationship between the target pollutant and predictors, while incorporating the associated air pollutants. We obtain high R² values of 0.76 and 0.73 through spatial and temporal cross validation, respectively. We evaluate estimation accuracy using an independent data set and achieve an R² of 0.75. Moreover, monthly variations for 2000–2013 are well reproduced with correlation coefficients of greater than 0.78, obtained through a comparison with observations. We estimate monthly means at 1 × 1 km resolution from 1987 through 2016. The estimates show decreases in the area and population weighted means beginning in the 1990s. We successfully estimate monthly mean PM2.5 concentrations over three decades with outstanding predictive accuracy. Our findings illustrate that the presented approach achieves accurate long-term historical estimations using observations limited in duration.
اظهر المزيد [+] اقل [-]Associations between exposure to metal mixtures and birth weight النص الكامل
2020
Yang, Xuefen | Li, Yuanyuan | Li, Juxiao | Bao, Shuangshuang | Zhou, Aifen | Xu, Shunqing | Xia, Wei
Previous epidemiological studies have indicated that prenatal exposure to individual metals affect fetal growth. However, the ordinary linear regression has not enough power to assess the mixture effect of multiple metals and cannot capture the possible differences in associations of metal exposures by subgroups of infant birth weight distribution. To investigate the associations of prenatal exposure to metal mixtures with birth weight, and further to assess whether the sensibilities to metal toxicity are dissimilar among infants with poor and normal fetal growth. A total of 16 metals were analyzed in 736 cord samples from a Chinese birth cohort study. Weighted quantile sum regression (WQSR) found the estimate of the metal mixtures was negatively related to birthweight z-score overall [β (95% CI): −0.31 (−0.42, −0.20)], and the major contributors to the mixture index were Cu (39.7%), Ni (18.3%), Mn (14.0%), and Cd (13.1%). Quantile regression showed stronger relations in the tails of birthweight z-score distribution [e.g. the associations of Cu at specific birth weight z-score quantiles were: 10th percentile −0.70 (95% CI: −1.06, −0.35), the 90th percentile −0.35 (95% CI: −0.63, −0.06)]. Our study found that prenatal exposure to Cu, Mn, Ni, and Cd were negatively linked with birthweight z-score. The associations observed were stronger in the tails of birth weight z-score distribution.
اظهر المزيد [+] اقل [-]Dioxins and PCBs – Environment impact on freshwater fish contamination and risk to consumers النص الكامل
2020
Mikolajczyk, Szczepan | Warenik-Bany, Malgorzata | Maszewski, Sebastian | Pajurek, Marek
This paper reports polychlorinated dibenzo-p-dioxins, dibenzofurans (PCDD/F) and polychlorinated biphenyls (PCB) concentrations in sediment and fish collected from Polish rivers in agricultural and urban areas and the associated risk for fish consumers. Total TEQ concentrations in fish muscles were in the range 0.29–7.25 pg WHO-TEQ g⁻¹ wet weight (w.w.). Generally, levels in sediment and fish muscles were low except for in the Vistula River in Cracow. In this fishery, total TEQ concentrations in sediments were high at 7.84 ± 1.73 pg WHO-TEQ g⁻¹ dry matter and fish were non-compliant with Commission Regulation (EU) 1259/2011/EU (3.5 pg WHO-TEQ g⁻¹ w.w. for PCDD/F and 6.5 pg WHO-TEQ g⁻¹ w.w. for total TEQ). Dioxin congener profiles in sediments were dominated by OCDD, and in the most contaminated fisheries in Cracow additionally by OCDF and 1,2,3,4,7,8-HxCDF. The most accumulated PCDD/Fs congeners in fish were 2,3,7,8-TCDF and 2,3,4,7,8-PeCDF except in Cracow, where 1,2,3,4,7,8-HxCDF dominated. The most abundant dioxin-like PCB (DL-PCB) and non-dioxin-like PCB (NDL-PCB) congeners were PCB 118 and PCB 153, respectively, both in sediment and fish muscles. The levels and profiles of contaminants in fish reflected the pollution of their environment. To characterize the potential health risk associated with dioxin and DL-PCB intake, doses ingested in two 100g portions of fish by adults and children were calculated and expressed as percentages of Tolerable Weekly Intake (TWI). Both values of TWI – that of 14 pg WHO-TEQ kg⁻¹ b.w. and the newer value of 2 pg WHO-TEQ kg⁻¹ b.w. established by the EFSA in November 2018 – were taken into account.It appears that regular consumption of some species could pose a health risk, especially those from urban areas.
اظهر المزيد [+] اقل [-]Response of sediment microbial communities to crude oil contamination in marine sediment microbial fuel cells under ferric iron stimulation النص الكامل
2020
Hamdan, Hamdan Z. | Salam, Darine A.
In this study, response of the microbial communities associated with the bioremediation of crude oil contaminated marine sediments was addressed using sediment microbial fuel cells (SMFCs). Crude oil was spiked into marine sediments at 1 g/kg of dry sediment to simulate a heavily contaminated marine environment. Conventional SMFCs were used with carbon fiber brushes as the electrode components and were enhanced with ferric iron to stimulate electrochemically active bacteria. Controls were operated under open circuit with and without ferric iron stimulation, with the latter condition simulating natural attenuation. Crude oil removal in the Fe enhanced SMFCs reached 22.0 ± 5.5% and was comparable to the measured removal in the control treatments (19.2 ± 7.4% in natural attenuation SMFCs and 15.2 ± 2.7% in Fe stimulated open circuit SMFCs), indicating no major enhancement to biodegradation under the applied experimental conditions. The low removal efficiency could be due to limitations in the mass transfer of the electron donor to the microbes and the anodes. The microbial community structure showed similarity between the iron stimulated SMFCs operated under the open and closed circuit. Natural attenuation SMFCs showed a unique profile. All SMFCs showed high relative abundances of hydrocarbon degrading bacteria rather than anode reducers, such as Marinobacter and Arthrobacter in the case of the natural attenuation SMFCs, and Gordonia in the case of iron stimulated SMFCs. This indicated that the microbial structure during the bioremediation process was mainly determined by the presence of petroleum contamination and to a lesser extent the presence of the ferric iron, with no major involvement of the anode as a terminal electron acceptor. Under the adopted experimental conditions, the absence of electrochemically active microbes throughout the biodegradation process indicates that the use of SMFCs in crude oil bioremediation is not a successful approach. Further studies are required to optimize SMFCs systems for this aim.
اظهر المزيد [+] اقل [-]De novo transcriptomic analysis predicts the effects of phenolic compounds in Ba River on the liver of female sharpbelly (Hemiculter lucidus) النص الكامل
2020
Guo, J. (Jiahua) | Mo, Jiezhang | Zhao, Qian | Han, Qizhi | Kanerva, Mirella | Iwata, Hisato | Li, Qi
This work aimed at predicting the toxic effects of phenolic compounds in Ba River on the health of female sharpbelly (Hemiculter lucidus) by the de novo transcriptomic analysis of the liver. Sharpbelly, a native fish living in freshwater ecosystem of East Asia, were sampled upstream, near, and downstream of a wastewater discharge to the Ba river. Based on the occurrence of bisphenol A (BPA), nonylphenol (NP), and 4-tert-octylphenol (4-t-OP) in the water and fish sampled from each site, up-, mid-, and down-stream were interpreted as control, high, and low treatment groups, respectively. In the mid-stream group the Fulton’s condition factor (CF) and body weight were remarkably increased by approximate 20%; the gonado-somatic index (GSI) and hepatosomatic index (HSI) in mid-stream fish showed a similar increasing trend but lacking of statistical difference. Exposure to wastewater effluent caused 160 and 162 differentially expressed genes (DEGs) in up-mid and down-mid stream groups, respectively. Two sets of DEGs were primarily enriched in the signaling pathways of drug metabolism, endocrine system, cellular process, and lipid metabolism in the mid-stream sharpbelly, which may alter the fish behavior, disrupt the reproductive function, and lead to hypothyroidism, hepatic steatosis, etc. Taken together, our results linked the disrupted signaling pathways with activities of phenolic compounds to predict the potential effects of wastewater effluent on the health of wild fish.
اظهر المزيد [+] اقل [-]Remediation of heavy metal contaminated soils by organic acid extraction and electrochemical adsorption النص الكامل
2020
Yang, Xiong | Liu, Lihu | Tan, Wenfeng | Liu, Chengshuai | Dang, Zhi | Qiu, Guohong
Remediation of heavy metal contaminated soils remains a global challenge. Here, low-molecular-weight organic acids were used to extract Cu and Zn from polluted soils, and the extracted heavy metals were subsequently adsorbed by activated carbon electrodes. The electrochemical adsorption mechanism as well as the influence of pH, organic acid type and voltage were investigated, and the soil remediation effect was further evaluated by the cultivation of rape. After extraction by citrate at initial pH 8.3 and electrochemical adsorption at 0.9 V for 7 d, the concentrations of total and bioavailable Cu in soils decreased from 1090 to 281 to 391 and 52 mg kg⁻¹, and those of Zn decreased from 262 to 39 to 208 and 30 mg kg⁻¹, respectively. Cu and Zn ions were mainly electrochemically adsorbed on the carbon cathode and anode, respectively, resulting in decreases of their concentrations to below 1 mg L⁻¹ in the leachate. The presence of organic acids improved the remediation performance in the order of citrate > oxalate > acetate. The decrease in the initial pH of citrate solution enhanced the removal rate of Zn, while seemed to have no effect on that of Cu. The removal capacity for heavy metals decreased with decreasing cell voltage from 0.9 to 0.3 V. In the rape cultivation experiment, the Cu and Zn contents in shoot and root were decreased by more than 50%, validating the soil remediation effect. The present work proposes a facile method for heavy metal removal from contaminated soils.
اظهر المزيد [+] اقل [-]Deoxynivalenol induced spermatogenesis disorder by blood-testis barrier disruption associated with testosterone deficiency and inflammation in mice النص الكامل
2020
Cao, Zheng | Huang, Wanyue | Sun, Yiran | Li, Yanfei
Deoxynivalenol (DON) is an unavoidable cereal crops contaminants and environmental pollutants, which seriously threated the health of human and animal. DON has been reported to exert significant toxicity effects on spermatogenesis, but the underlying mechanisms remain largely inconclusive. The blood-testis barrier (BTB) provides a specialized biochemical microenvironment for maintaining spermatogenesis. Thus, we hypothesized that DON could impair BTB and lead to spermatogenesis disorder. To confirm this hypothesis, sixty male mice were intragastrically administered with 0, 1.2, 2.4 and 4.8 mg/kg body weight DON for 28 days, and several important observations were obtained in present study. First, we found that DON induced spermatogenesis disorder, reflected by the declines of sperm concentration and quality, sperm ultrastructural damage as well as seminiferous tubular damage. Then, we proved that DON induced BTB disruption as well as decreased the expressions of BTB junction proteins, including Occludin, Connexin 43 and N-cadherin. Finally, the present study showed that DON induced inflammation and inhibited T biosynthesis in testis of mice. These results revealed that DON induced spermatogenesis disorder by BTB disruption associated with testosterone deficiency and inflammation in mice, which shed a new light on the potential mechanisms of reproductive toxicity induced by DON.
اظهر المزيد [+] اقل [-]Excretion characteristics and tissue accumulation of tetrabromobisphenol-A in male rats after sub-chronic inhalation exposure النص الكامل
2020
Yu, Yun jiang | Chen, Xi chao | Wang, Zheng-Dong | Liu, Liting | Ge, Qing zhi | Wang, Qiong | Zhang, Yan ping | Yu, Zi ling | Ma, Rui xue
Tetrabromobisphenol-A (TBBPA) is an emerging organic pollutant and a commonly used brominated flame retardant that has received much attention owing to its toxicity. Although TBBPA is ubiquitously detected in atmospheric particulate matter and dust, few studies have investigated the sub-chronic inhalation exposure to TBBPA. To further understand the excretion characteristics and tissue accumulation of TBBPA after inhalation exposure, we used the rat model to conduct a sub-chronic inhalation exposure study. Male rats were administered with different doses of aerosol TBBPA (12.9, 54.6, 121.6, and 455.0 mg/m³). TBBPA was found in the excretion (feces and urine) and all the target tissues (lung, liver, heart, thymus gland, spleen, testicles, muscles, kidneys, brain and serum). Feces were the main route of excretion, which contributed 19.18% to 72.54% (urine <0.10%). TBBPA excretion through feces following inhalation administration was much higher than that following oral and dermal exposure, thereby indicating lower bioavailability of TBBPA under inhalation exposure. Liver and serum showed higher levels of TBBPA compared with those of other tissues, thereby suggesting tissue-specific accumulation of TBBPA in rats. Owing to the relative non-invasiveness of serum sampling and greatest TBBPA concentration among the tissues, serum is a suitable matrix for estimation of TBBPA bioaccumulation after inhalation exposure.
اظهر المزيد [+] اقل [-]Exposure of U.S. population to endocrine disruptive chemicals (Parabens, Benzophenone-3, Bisphenol-A and Triclosan) and their associations with female infertility النص الكامل
2020
Arya, Sushila | Dwivedi, Alok Kumar | Alvarado, Luis | Kupesic-Plavsic, Sanja
Ubiquitous exposure to endocrine disruptive chemicals (EDC) among women of reproductive age is alarming. Exposure to EDCs could be contributing to infertility. We determined the association between common EDCs and self-reported infertility among U.S. women, 18–45 years of age using the National Health and Nutrition Examination Surveys (NHANES) for periods 2013–2014 and 2015–2016. A cross-sectional study on reproductive age women was conducted. Available important sociodemographic variables, and urinary concentrations of parabens (methyl paraben [MP], ethyl paraben [EP], propyl paraben [PP], and butyl paraben [BP]), Benzophenone-3 (BP-3), Bisphenol-A (BPA), and triclosan (TCS) were obtained from the NHANES databases. Clustering among EDCs were obtained using variable cluster analysis. Relative risk regression models were used to estimate associations of individual and combined EDCs with self-reported infertility after applying appropriate survey weights to account for the complex survey design as well as to compensate for the four-year cycle. Results were summarized using prevalence ratio (PR) with 95% confidence interval (CI). Of total 789 individuals included in the study, 14% (95%CI: 11%–18%) had infertility. MP and PP were detected in 99% of urine samples, BP in 46%, EP and BP-3 in 96%, BPA in 94% and TCS in 73%. Self-reported infertility was significantly associated with combined score of BP-3, BPA and TCS (PR = 1.13, p = 0.007), and above detection level of EP (PR = 1.57, p = 0.025) even after adjusting for potential confounders. Our results suggested the EP and mixtures of benzophenones, TCS, and BPA were associated with infertility among the U.S. women. However, because of the limitations inherent to the cross-sectional study design, prospective cohort studies are warranted to confirm these findings.
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