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Abstract Microcystis aeruginosa and hepatotoxic microcystins produced by it have posed a severe threat to aquatic ecological security and human health. In this study a Streptomyces amritsarensis HG-16, showing high algicidal activity against M. aeruginosa and strong inhibitory effect on microcystin synthesis, was obtained by screening some anti- Fusarium sp. microbial strains isolated before in our laboratory. HG-16 bound cyanobacterial cells by mycelia to form flocs and killed M. aeruginosa by secreting active substances, which were proteinase K resistant and stable in the temperature range of 35–75 °C and pH range of 3–11. HG-16 removed M. aeruginosa of 105 and 106 cell mL−1 cell densities in similar rate and was active against all the tested harmful unicellular and filamentous cyanobacteria. Results of differential gene expression analysis indicated that HG-16 affected the photosynthesis system and microcystin synthesis of M. aeruginosa. Accordingly, the algicidal activity of HG-16 was light-dependent, and microcystin synthesis of M. aeruginosa decreased by 91.2% with HG-16 treatment. Thus, it is promising to utilize HG-16 to mitigate harmful cyanobacterial blooms, inhibit microcystin synthesis and control plant disease caused by Fusarium. spp. through irrigating farmland with eutrophic water applied HG-16. Graphical abstract Unlabelled Image Highlights • An algicidal Streptomyces amritsarensis strain HG-16 was obtained. • HG-16 killed Microcystis and inhibited microcystin synthesis effectively. • HG-16 bound algae to form flocs and exerted activity by releasing stable compounds. • Photosynthesis system and cell integrity of Microcystis were the targets of HG-16. • HG-16 grew on nutrient from lysed algae to form active substrates against Fusarium. [ABSTRACT FROM AUTHOR]

In the largest developing country, China, plastic has become a serious environmental issue because of its overuse and non-treatment. In fact, plasticizers, such as phthalate esters (PAEs), are more toxic than plastic, and their global awareness is rising. To determine the response of sensitive PAE congeners to the anthropogenic activities in a typical lake ecosystem of China, in the present study, 12 PAEs in the water and the suspended particulate matter (SPM) phases of 46 lakes in China were measured. The concentrations of all the Σ 12 PAEs in water and SPM phases ranged from 3.647 to 65.618 μg/L and 0.175 to 10.921 μg/L, respectively. Di-n-butyl phthalate (DnBP) was the predominant PAEs in the water phase, whereas diisobutyl phthalate (DIBP), DnBP, and bis(2-ethylhexyl) phthalate (DEHP) were the dominating PAEs in the SPM phase. Forty-six lakes were divided into four groups based on the anthropogenic activity intensities. The PAEs in both the water and SPM phases had increasing tendency along the human activity gradient. DIBP appears to be a sensitive PAE indicator that could distinguish the lake regions with different human industrial and agricultural activities. Dimethyl phthalate (DMP) and diethyl phthalate (DEP) are intensely affected by industrial development. DnBP and DEHP were positively correlated with agricultural activities, including the use of films and pesticides. It is suggested to control the addition and usage of PAEs in agricultural activities and improve their removal rates in industrial wastewater to reduce the PAE pollution in the water bodies in the environment management of China. Unlabelled Image • DnBP predominant in water while DIBP, DnBP and DEHP predominant in SPM • PAEs had increasing tendency along the human activity gradient. • DIBP sensitively response to PAE-related human activities. • DMP and DEP were deeply affected by industrial development. • DnBP and DEHP were positively correlated with agricultural activities. [ABSTRACT FROM AUTHOR]

The understanding of soil microbiome is important for sustainable cultivation, especially under greenhouse conditions. Here, we investigated the changes in soil pesticide residues and microbial diversity and community structure at different cultivation years under a greenhouse system. The 9-to-14 years sites were found to have the least diversity/rich microbial population as compared to sites under 8 years and over 16 years, as analyzed with alpha diversity index. In total, 42 bacterial phyla were identified across soils with different pesticide residues and cultivation ages. Proteobacteria , Acidobacteria , and Bacteroidetes represented the dominant phyla, that accounted for 34.2–43.4%, 9.7–19.3% and 9.2–16.5% of the total population, respectively. Our data prove that certain pesticides contribute to variation in soil microbial community and that soil bacteria respond differently to cultivation years under greenhouse conditions. Thus, this study provides an insight into microbial community structure changes by pesticides under greenhouse systems and natural biodegradation may have an important part in pesticides soil decontamination. Unlabelled Image • The total concentrations of pesticides increased first, and then decreased with cultivation years increased. • The diversity of bacteria decreased first, and then increased with cultivation years increased. • Some microbe phylum and genera significantly associated with pesticides. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) have become a major type of pollutant in urban areas and their degree of pollution and characteristics of spatial distribution differ between various regions. We conducted a comprehensive study about the concentration, source, spatial distribution, and health risk of 16 PAHs from urban to rural soils in Nanjing. The mean total concentrations of 16 PAHs (∑ 16 PAHs) were 3330 ng g − 1 for urban soils, 1680 ng g − 1 for suburban soils, and 1060 ng g − 1 for rural soils. Five sources in urban, suburban, and rural areas of Nanjing were identified by positive matrix factorization. Their relative contributions of sources to the total soil PAH burden in descending order was coal combustion, vehicle emissions, biomass burning, coke tar, and oil in urban areas; in suburban areas the main sources of soil PAHs were gasoline engine and diesel engine, whereas in rural areas the main sources were creosote and biomass burning. The spatial distribution of soil PAH concentrations shows that old urban districts and commercial centers were the most contaminated of all areas in Nanjing. The distribution pattern of heavier PAHs was in accordance with ∑ 16 PAHs, whereas lighter PAHs show some special characteristics. Health risk assessment based on toxic equivalency factors of benzo[a]pyrene indicated a low concentration of PAHs in most areas in Nanjing, but some sensitive sites should draw considerable attention. We conclude that urbanization has accelerated the accumulation of soil PAHs and increased the environmental risk for urban residents. [ABSTRACT FROM AUTHOR]

Numerous methods have been implemented to evaluate the relationship between environmental factors and respiratory mortality. However, the previous epidemiological studies seldom considered the spatial and temporal variation of the independent variables. The present study aims to detect the relations between respiratory mortality and related affecting factors across Xi'an during 2014–2016 based on a novel geographically and temporally weighted regression model (GTWR). Meanwhile, the ordinary least square (OLS) and the geographically weighted regression (GWR) models were developed for cross-comparison. Additionally, the spatial autocorrelation and Hot Spot analysis methods were conducted to detect the spatiotemporal dynamic of respiratory mortality. Some important outcomes were obtained. Socioeconomic and environmental determinants represented significant effects on respiratory diseases. The respiratory mortality exhibited an obvious spatial correlation feature, and the respiratory diseases tend to occur in winter and rural areas of the study area. The GTWR model outperformed OLS and GWR for determining the relations between respiratory mortality and socioeconomic as well as environmental determinants. The influence degree of anthropic factors on COPD mortality was higher than natural factors, and the effects of independent variables on COPD varied timely and locally. The results can supply a scientific basis for respiratory disease controlling and health facilities planning. Unlabelled Image • The epidemiological, environmental, and socioeconomic datasets were collected for modeling. • The spatiotemporal heterogeneity of respiratory diseases was demonstrated. • The relations between respiratory diseases and related affecting factors were estimated. • Respiratory diseases tend to occur in winter and rural areas of the study area. • The efforts of anthropic factors on COPD mortality were larger than natural factors. [ABSTRACT FROM AUTHOR]

Neonicotinoid insecticides (NNIs) are the most widely used insecticides in China and worldwide. Continuous use of NNIs can lead to their accumulation in soil, causing potential ecological risks due to their relatively long half-life. We used liquid chromatography-tandem mass spectrometry (LC-MS/MS) to investigate the residual levels of nine neonicotinoids in greenhouse soils in Shouguang, East China, at different soil depths and with different crops (tomato and cucumber) after varying periods of cultivation. Seven neonicotinoids were detected in the soils of the tomato greenhouses and six were detected in the soils of the cucumber greenhouses, with total concentrations ranging from 0.731 to 11.383 μg kg−1 and 0.363 to 19.224 μg kg−1, respectively. In all samples, the neonicotinoid residues in the soils cultivated for 8–9 years were lower than in those cultivated for 2 years and 14–17 years. In the tomato greenhouse soils, the residual levels of NNIs were highest in the topsoil, with progressively lower concentrations found with depth. Under cucumber cultivation, the NNI residue levels were also highest in the topsoil but there was little difference between the middle and lower soil layers. Total organic carbon (TOC) decreased with soil depth while pH showed the opposite trend, showing a significant negative correlation in both types of soils (tomato soils ρ = −0.900, p =.001; cucumber soils ρ = −0.883, p =.002). Furthermore, TOC was significantly positively correlated, and pH was negatively correlated, with total NNI concentrations in both types of soils (TOC: tomato soils ρ = 0.800, p =.010; cucumber soils ρ = 0.881, p =.004; pH: tomato soils ρ = −0.850, p =.004; cucumber soils ρ = −0.643, p =.086). The results of an ecological risk analysis showed that acetamiprid represents a particularly high toxicity risk in these soils. Based on our analysis, NNI residues in the soils of tomato greenhouses and their associated ecological risks deserve more attention than those of cucumber greenhouse soils. Unlabelled Image • Neonicotinoid residues in topsoil were higher in both tomato and cucumber greenhouses. • The total amount of neonicotinoids in soil was significantly positively correlated with TOC. • The total amount of neonicotinoids in soil was significantly negatively correlated with pH. • Acetamiprid was with high ecological risks based on acute SSD models. • Greatest neonicotinoid effects in short-term cucumbers and long-term tomatoes greenhouse soils [ABSTRACT FROM AUTHOR]

Dimethylformamide (DMF) is a volatile organic compound listed as one of the four toxicants with the highest priority for human field study. However, the effect of DMF exposure on lung function and the underlying mechanisms remain unknown. We aimed to investigate the exposure-response relationship and possible mechanism between internal DMF exposure and lung function alteration. We studied 3701 Chinese adults from the Wuhan-Zhuhai cohort with a 3-year follow-up. The cross-sectional relationship between urinary biomarker of DMF exposure (N -Acetyl-S-(N -methylcarbamoyl)-L-cysteine, AMCC) and lung function, and the mediating role of plasma C-reactive protein (CRP) were assessed. We also convened a sub-cohort (N = 138) to assess the stability of AMCC in repeated urine samples collected for continuous 3 days and intervals of 1, 2 and 3 years. The longitudinal association between AMCC and lung function change in 3 years was further assessed. We found a dose-response relationship between AMCC and lung function reduction. Each 2-fold increase in AMCC was cross-sectionally associated with a 23.12-mL (95% CI: −36.68, −9.55) decrease in FVC and a 19.01-mL (95% CI: −31.08, −6.93) decrease in FEV 1. Increased CRP significantly mediated 5.39% and 5.87% of the AMCC-associated FVC and FEV 1 reductions, respectively. With 3-year follow-up, AMCC showed a fair to excellent stability (intra-class correlation coefficients were 0.88, 0.55, 0.60 and 0.50 for continuous 3 days, intervals of 1, 2 and 3 years, respectively) and was dose-dependently associated with longitudinal lung function decline. Compared with those with persistent low AMCC levels, participants with persistent high AMCC levels had a 101.09-mL/year (95% CI: −167.40, −34.77) decline in FVC and a 66.27-mL/year (95% CI: −114.14, −18.41) decline in FEV 1 in the sub-cohort. Similar results were found in the full-cohort. Our findings suggest that exposure of general population to environmental DMF may impair lung function, and systematic inflammation may be an underlying mechanism. Unlabelled Image • Urinary biomarker of DMF exposure (AMCC) was negatively associated with lung function. • Urinary AMCC was positively associated with plasma C-reactive protein (CRP). • Plasma CRP mediated urinary AMCC-associated lung function reduction. • Urinary AMCC showed a fair to excellent reproducibility during a 3-year period. • Higher urinary AMCC level was associated with lung function decline in 3 years. [ABSTRACT FROM AUTHOR]