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Although the contamination of microplastics (MPs) in groundwater has been anticipated, their occurrence, distribution, and composition require further understanding. In this study, the occurrence and distributions of MPs were investigated in shallow groundwater from an important water source district in Tianjin city of northern China. The abundance, the physical morphology, the chemical composition, and the potential correlations of the determined MPs with human activities were thoroughly characterized. MPs were determined from all ten sampling sites with the abundance ranged between 17.0 ± 2.16 to 44.0 ± 1.63 n/L, revealing the ubiquitous existed MPs contamination. Based on the physical categorization, fiber (44.74%) was the most abundant shape, while blue (31.02%) and transparent (26.09%) were the most prevalent colors. The dominant size of MPs was smaller than 200 μm which accounted for 73.10%. A total of seven types of MPs were determined with polyethylene, polyethylene terephthalate, and polystyrene as the main types, of which, polypropylene showed strong positive correlations with polystyrene, indicating the possible similar sources of them. Besides, the determined MPs in groundwater were greater in areas with the high population density and strong population activity, indicating their high correlation with human activity. The study highlighted the presence of MPs in groundwater of drinking water source in northern China and provided useful information for evaluating the potential ecological effects on water quality safety and human health brought by MPs. • Microplastics were ubiquitously existed in groundwater at ten different points. • Seven polymer types were determined with PET as predominant. • Blue colored fibrous MPs with size of less than 200 μm were dominant. • Abundance of microplastics is closely related to human activity. [ABSTRACT FROM AUTHOR]

Considering the live SARS-CoV-2 was detected and isolated from the excrement and urine of infected patients, the potential public health risk of its waterborne transmission should be paid broad and close attention. The purpose of the current study is to investigate the associations between COVID-19 incidences and hydrological factors such as lake area, river length, precipitation and volume of water resources in 30 regions of China. All confirmed cases for each areas were divided into two clusters including first cases cluster driven by imported cases during the period of January 20th to January 29th, 2020 and second cases cluster driven by local cases during the period of January 30th to March 1st, 2020. Based on the results of descriptive analysis and nonlinear regression analysis, positive associations with COVID-19 confirmed numbers were observed for migration scale index (MSI), river length, precipitation and volume of water resources, but negative associations for population density. The correlation coefficient in the second stage cases cluster is apparently higher than that in the first stage cases cluster. Then, the negative binomial-generalized linear model (NB-GLM) was fitted to estimate area-specific effects of hydrological variables on relative risk (RR) with the incorporation of additional variables (e.g., MSI) and the effects of exposure-lag-response. The statistically significant associations between RR and river length, the volume of water resources, precipitation were obtained by meta-analysis as 1.24 (95% CI: 1.22, 1.27), 2.56 (95% CI: 2.50, 2.61) and 1.59 (95% CI: 1.56, 1.62), respectively. The possible water transmission routes of SARS-CoV-2 and the potential capacity of long-distance transmission of SARS-CoV-2 in water environment was also discussed. Our results could provide a better guidance for local and global authorities to broaden the mind for understanding the natural-social system or intervening measures for COVID-19 control at the current or futural stage. • Associations between COVID-19 incidences and hydrological factors were identified. • All cases were divided into two clusters to eliminate the effect of imported cases. • The effects of exposure-lag-response of migration scale index were evaluated. • NB-GLM was well fitted with the incorporation of additional variables. [ABSTRACT FROM AUTHOR]

Cadmium is a recognized human carcinogen, raising global concern for its ubiquitously environmental exposure on public health. Diabetogenic effects of cadmium have been suggested in previous studies, but the longitudinal associations of chronic cadmium exposure with fasting blood glucose changes and type 2 diabetes mellitus have not been fully elucidated. To investigate the effects of long-term cadmium exposure on the fasting blood glucose changes and type 2 diabetes mellitus risk in a longitudinal prospective study of China. A total of 3521 urban adults were included as baseline study population from the Wuhan-Zhuhai cohort, and followed up three years later. Urinary cadmium concentrations were determined repeatedly during the follow-up of a three-year period. The within-person and between-person variability of urinary cadmium concentrations over three years was estimated using multilevel random-effects mixed models. Multivariate regression models were performed to evaluate the associations of cadmium exposure with fasting blood glucose changes and type 2 diabetes mellitus risk. The geometric means of creatinine-corrected urinary cadmium concentration at baseline were 1.13 μg/g creatinine, which were close to the levels of follow-up (1.14 μg/g creatinine). The intra-class correlation coefficient of creatinine-corrected urinary cadmium concentrations was 0.71, achieving good reproducibility of cadmium over three years. With adjustment for potential confounders, each one-unit increase in log10-transformed cadmium was associated with a 0.11 (95%CI: 0.03 to 0.19) elevation in fasting blood glucose concentration, and was associated with a 42% (95%CI: 1.16 to 1.73) increase in risk of prevalent type 2 diabetes mellitus. Upward trends of fasting blood glucose changes and type 2 diabetes mellitus incidence were observed with increasing cadmium exposure. Individuals with the highest urinary cadmium exposure had a significant increase in fasting blood glucose change at follow-up [β (95% CI): 0.49 (0.31–0.67)]. Risk of incident type 2 diabetes mellitus were gradually elevated across increasing quartiles of cadmium exposure, though associations did not reach statistical significance (P = 0.15). Our findings suggested that relatively high chronic cadmium exposure for general population adults might contribute to elevated changes of fasting blood glucose resulting in the development of type 2 diabetes mellitus. • Excellent reproducibility was achieved for urinary Cd levels over three years. • Significant associations observed for urinary Cd with FBG and prevalent T2DM risk. • Individuals with high Cd exposure had a significant increase in FBG at follow-up. • Risk of incident T2DM were gradually elevated across increasing urinary Cd. • Associations were further confirmed in penalized regression splines models. [ABSTRACT FROM AUTHOR]

The coastal area of Yancheng, China, is one of the hotspots for ecological research. Under the coupling of human and natural ecosystems, the region has gradually evolved into a coexistence of aquatic, agricultural and mudflat ecosystems. What are the patterns of natural and artificial resource inputs and patterns of change in ecosystems? How can ecological flows be analyzed at a uniform scale? Here, we selected six typical local ecosystems, namely, rice‒wheat for enterprises (RWE), rice‒wheat for smallholder households (RWS), chrysanthemum‒wheat (CW), fish polyculture (FP), juvenile crab farming (JF) and clam polyculture (CP), and analyzed their energy flow flux and sustainability based on emergy theory. The results showed that anthropogenic resource inputs were higher than natural resource inputs in all ecosystems, and the inputs of aquatic ecosystems were greater than those of agroecosystems. The greatest total input was 2.0 E+17 seJ/ha/yr for FP, and the lowest was 1.9 E+16 seJ/ha/yr for RWE. The proportions of renewable and artificial inputs for RWE, RWS, CW, FP, JF and CP were 32.8% vs. 96.1%, 40.3% vs. 96.5%, 34.7% vs. 97.0%, 32.6% vs. 99.4%, 55.1% vs. 98.5%, and 62.5% vs. 98.6%, respectively. The highest input to agroecosystems was nitrogen fertilizer, while in JF and CP, it was water, and feed (63.3%) accounted for the highest percentage of input in FP. JF and CP had lower environmental loads and higher sustainability than other ecosystems, but this still represents a high input compared to agroecosystems. Human-led resource coupling profoundly affects ecosystem sustainability, and various thresholds of energy use and ecological sustainability need to be studied in depth. Continuous exploration of methods and mechanisms for the maintenance and evolution of ecosystems with low total inputs and low inputs of non-renewable resources can contribute to high-quality sustainable development of an area or region. • Multi-systems are sustained by various forms of natural and artificial resources. • The total emergy input to the aquatic ecosystem is 1.9 E+16∼2.4 E+16 seJ/ha/yr. • Agroecosystems have a total emergy input of 7.7 E+16∼2.0 E+17 seJ/ha/yr. • The range of renewable resources in aquatic ecosystems of coastal area is 34.7–47.4%. • The percentage of renewable resources in agricultural systems is 32.6–62.5%. [ABSTRACT FROM AUTHOR]

Increasing discharge of excessive phosphorus (P) has caused widespread eutrophication and water pollution that threaten both ecological and human health. There are many ways to remove P from eutrophic water, but there are various deficiencies. Conventional P removal is based largely on the use of Al or Fe salts and few methods can be directly used in field eutrophic water. Our research revealed that direct use of ordinary Portland cement could effectively remove P from eutrophic water bodies. Laboratory experiments indicate that a one-time application of cement reduced Total Phosphorus (TP) concentration of both eutrophic urban water and synthetic solutions to below 0.2 mg/L. A second application further reduced TP to below 0.04 mg/L. Use of cement also caused an increase in dissolved oxygen (DO) content in samples. Cement was directly used in eutrophic water body of a river and TP concentration was reduced to an allowable level. Use of readily available cement can contribute to the clean up of water pollution in developing countries. This study provides an innovative and easy solution to widespread eutrophication. • Excessive nutrient discharge have caused widespread eutrophication in China. • Conventional water phosphorus removal methods have proved insufficient. • Direct use of cement efficiently reduced water phosphorus to allowable level. • New use of cement in eutrophic water contribute to cleanup of eutrophication. [ABSTRACT FROM AUTHOR]

In groundwater environments, the interaction between microbial communities and the hydrogeochemical parameters have been investigated extensively in the past years. However, little is known whether the maximum contamination level (MCL) is a threshold value that dictates the microbial composition. In this study, we analyzed 10 groundwater samples for their nitrate, nitrite, COD and sulfate concentrations, and characterized their microbial compositions using 16 S rRNA based high-throughput sequencing methods. All the 10 samples had oxygen demands higher than the corresponding MCL of China (10 mg L−1); moreover, 4 out of 10 samples also had nitrate concentrations higher than the corresponding MCL, which indicated that the groundwater quality was negatively impacted by anthropogenic activities. Comparing the microbial composition of groundwater that had higher-than-MCL nitrate concentrations to those that had lower-than-MCL nitrate concentrations, no significant differences were detected in communities' richness and diversity. However, the non-metric multi-dimensional analysis suggested that the 4 groundwater samples whose nitrate concentration exceed MCL are distinctly different from those of the rest 6 samples, indicating that MCL does have a significant impact on microbial structures. Pearson's correlation analysis suggested that none of the four analyzed hydrochemical parameters had significant impact on microbial communities' richness and diversity; however, at the genus level, the correlation results suggested that JG3 0-KM -CM45 , Sphingomonas and Rhodococcus are closely correlated with nitrate concentration. The findings of this study deepened our understanding with respect to the relationships between the environmental quality indices and the microbial compositions of groundwater. • Impact of higher-than-MCL nitrate on microbial communities' structure were examined • No significant differences were found in richness and diversity • NMDS revealed higher-than-MCL NO3 led to distinct groundwater microbial community • JG-30-KM-CM45, Sphingomonas and Rhodococcus closely related with NO3 concentration [ABSTRACT FROM AUTHOR]

Atmospheric amines have attracted increasing attention due to their significant impact on new particle formation, particle hygroscopicity and particle optical properties. In this study, four low-molecule-weight amines were detected from PM 2.5 filter samples collected at an urban site of Pearl River Delta (PRD) region of China in 2018 autumn. During the campaign, the mass concentrations of ambient particulate methylamine (MA, CH 3 NH 2), dimethylamine (DMA, (CH 3) 2 NH), trimethylamine (TMA, (CH 3) 3 N), and diethylamine (DEA, (C 2 H 5) 2 NH) were quantified at daily or 12-h resolution using an optimized Ion Chromatograph (IC) method. The total measured amine concentration was 297 ± 209 ng/m3, which can account for 0.76 ± 0.33% of PM 2.5 mass concentrations. The particulate amines in PRD urban area were dominated by MA (243 ± 179 ng/m3), accounting for over 80% of total amines, then followed by DMA (49 ± 30 ng/m3, 16.5%), TMA (4 ± 2 ng/m3) and DEA (1 ± 1 ng/m3). Based on the correlation analysis, MA and DMA mainly presented as nitrate and sulfate salts. We speculate the amines tend to react with gas-phase HNO 3 or particle-phase nitrate to form particulate amine salts via local process in Guangzhou. As the relative humidity (RH) increased, enhanced partitioning of amine towards the particle phase was observed. Using approach of multiple linear regression, 71% of the particulate amines in PRD urban site could be explained by acid-base process and the rest by primary emissions from combustion sources (29%). • Particulate amines in urban PRD were quantified using an optimized IC method. • Methylamine was the most abundant amine, followed by dimethylamine. • Methylamine and dimethylamine mainly presented as nitrate and sulfate salts. • Enhanced RH facilitated the partitioning of amine towards particle phase. • Acid-base process dominated the amine formation, the left by combustion source. [ABSTRACT FROM AUTHOR]

Black-odour water with organic compounds and heavy metals caused by domestic and industrial activities has aroused people's attention in recent years, yet little is known about the ecological effects on aquatic organisms, especially microorganisms in sediments. To explore the response of microbial communities to environmental factors, the community and metabolites of nine river sediments with different pollution in Dongguan city, China were investigated using 16S rRNA gene sequencing and liquid chromatography tandem-mass. The results revealed that the composition and structure of sedimentary microbial communities significantly changed in rivers with varying pollution levels. Cyanobacteria were the most abundant organisms in the sediment of black-odorous rivers, while the relative abundance of Thaumarchaeota was gradually increased with the river quality gets better. The relative abundance of organic acids (including amino acids), alcohols, esters, and ketones associated with microbial metabolism in sediments of polluted rivers was increased. The 16S rRNA gene sequencing-based molecular ecological network analysis indicated that the interactions amongst bacteria were enhanced in severely contaminated communities. Sphingomonadaceae and Cyanobacteria have important roles in bacterial community structures of polluted rivers and those with ongoing treatment. The correlation analysis showed significant metal resistance and/or tolerance of the following bacteria species Thalassiosira weissflogii , Aminicenantes bacterium clone OPB95 , 'Candidatus Halomonas phosphatis' , and archaeal species Methanolinea and unidentified Thermoplasmata. These results indicated that sedimentary microbial communities may shift in composition and structure, as well as their interaction network, to adapt and resist environmental contamination and promote restoration. [ABSTRACT FROM AUTHOR]

Wastewater treatment plants (WWTPs) play a critical role in the sustainable development of water resources due to its outstanding ability of removing pollutants from complex influent wastewater and generating clean and safe effluent. This paper innovatively adopted the meta-analysis method in view of published LCA studies to assess the energy use and environmental impacts of WWTPs during their life cycle. The search and screening process determined a useful data source with 54 LCA literatures covering 109 relevant case studies. The meta-analysis results revealed that, compared with other regions, the WWTPs in China have the higher intensity in terms of energy use, global warming potential (GWP), eutrophication potential (EP), acidification potential (AP), photochemical oxidation (PHO), freshwater ecotoxicity potential (FETP) and terrestrial ecotoxicity potential (TETP) categories, implying that the energy conservation and emission reduction strategies are necessary to wastewater treatment industry in China. Moreover, compared with A/A/O and CASS processes, the A/O process consumes less energy and results in lower GWP and AP intensity, but affects adversely the natural water-body protection due to undesirable treatment efficiency. Furthermore, the treatment capacities of medium and large scales (i.e. 5-20 × 104 m3/d) are most reasonable sizes for WWTPs since their intensity of energy use, GWP, EP and AP are under a relatively low level. Finally, a strict effluent discharge standard is highly recommended from the perspective of protecting aquatic environment, although it leads to a higher energy consumption. The findings of this study could provide valuable references for promoting healthy and sustainable wastewater treatment industry. • Meta-analysis was firstly explored for evaluating the energy use and EIs of WWTPs. • Data source included 54 LCA literatures covering 109 independent case studies. • Four physical characteristics associated with WWTPs were in-depth discussed. • Recommendations for design and reconstruction of WWTPs in the future were provided. [ABSTRACT FROM AUTHOR]

Few prospective cohort studies have investigated associations between environmental tobacco smoke (ETS) and other cancer sites, in addition to lung cancer. We assessed these associations in a population-based prospective cohort study started from 2008 to 2011 with average of 9.1 years of follow-up, in Minhang district, Shanghai, China. The study included a total of 23,415 participants (8388 men, 15,027 women) and 205,515 person-years. Epidemiological data were collected by a standardized questionnaire including ETS exposure. Newly diagnosed patients with primary cancers and deaths were identified by record linkage system with the Shanghai Cancer Registry and Shanghai Vital Statistics. Hazard ratios (HRs) and their 95% confidence intervals (CIs) were estimated using Cox proportional hazards regression models, adjusting for potential confounders. During the study period, a total of 1462 patients with diagnoses of primary cancers were identified. Among all participants and non-smokers, ETS was associated with an increased risk of all smoking-related cancers (all: adjusted HR: 1.23, 95% CI: 1.05–1.43 and non-smokers: 1.24, 1.02–1.49), lung cancer (1.29, 0.98–1.71 and 1.27, 0.91–1.77), and stomach cancer (1.86, 1.21–2.85 and 1.75, 1.05–2.91), respectively. Furthermore, associations for lung and stomach cancers were the strongest among non-smoking females. The joint effects of both ETS and active smoking were strongest for all cancers, all smoking-related cancers, lung cancer, and stomach cancer. No clear interactions were observed. These results suggest that ETS exposure may increase the risk of smoking-related cancers in a Chinese population. Further studies on the relationship between ETS exposure and specific cancer sites are warranted to replicate our findings. • Exposure to ETS was associated with the risk of smoking-related, lung and stomach cancers in non-smokers and all participants. • Associations between ETS and lung cancer, stomach cancers were the strongest among non-smoking females. • Joint effects of both ETS and active smoking were observed for all cancers, smoking-related cancers, lung and stomach cancers. • No clear associations were observed between ETS exposure and the risk of overall cancer and other cancer sites. [ABSTRACT FROM AUTHOR]