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Assessment of currently used organochlorine pesticides in surface water and sediments in Xiangjiang river, a drinking water source in China: Occurrence and distribution characteristics under flood events
2022
Zhang, Shengwei | Zhao, Wenyu | Yang, Chao | Li, Yanxia | Liu, Mengyue | Meng, Xiang−Zhou | Cai, Minghong
Xiangjiang (XJ) is a typical urban inland river that serves as a drinking water source, which may be affected by the currently used organochlorine pesticides (CUOCPs) originating from agricultural activities in the vicinity. On this basis, this study comprehensively explored the occurrence and distribution characteristics of CUOCPs in surface water and sediments under long-term precipitation and subsequent floods. Considering the low concentration of CUOCPs in water, a technique combining high-throughput organic analysis with high-volume solid phase extraction (High-throat/Hi-volume SPE) was introduced for effective analysis of CUCOPs. The results showed that the concentration of CUOCPs in the water and sediments of XJ ranged from 2.33 to 6.40 ng L⁻¹ (average of 3.93 ± 1.15 ng L⁻¹) and from 1.52 to 21.2 ng g⁻¹ (average of 6.60 ± 4.31 ng g⁻¹ dw), respectively. The distribution of CUOCPs in water was consistent throughout XJ, but that in sediments was not uniform, indicating a stronger impact of floods on water than on sediments. Water-sediment partition coefficients were generally >2 L g⁻¹, showing a tendency of CUOCP dominance in sediments. The results of principal component analysis and cluster analysis showed that the occurrence of CUOCPs is significantly affected by exogenous disturbance, which could be flood events; meanwhile, clusters of CUOCPs were found in both water and sediments in the source-limited middle reaches in urban areas. Redundancy analysis (RDA) showed that CUOCP occurrences were not positively correlated with nutrient elements (nitrogen and phosphorus), but related to pH and dissolved oxygen (DO), indicating complex sources.
显示更多 [+] 显示较少 [-]Feeding on grains containing pesticide residues is detrimental to offspring development through parental effects in grey partridge
2022
Gaffard, Agathe | Pays, Olivier | Monceau, Karine | Teixeira, Maria | Bretagnolle, Vincent | Moreau, Jérôme
Numerous toxicological studies have shown that ingestion of pesticides can induce physiological stress in breeding birds, with adverse consequences on egg laying parameters and offspring quality through parental effects. However, previous studies do not mimic current levels of pesticide residues in typical landscapes, and they do not consider potential cocktail effects of pesticides as they occur in the wild. Herein, we explored whether realistic pesticide exposure affected reproduction parameters and offspring condition through parental effects in Grey partridge. We fed 24 breeding pairs with either seeds from conventional agriculture crops treated with various pesticides during cropping, or organic grains without pesticide residues as controls. The conventional and organic grain diets mimicked food options potentially encountered by wild birds in the field. The results showed that ingesting low pesticide doses over a long period had consequences on reproduction and offspring quality without altering mortality in parents or chicks. Compared with organic pairs, conventional pairs yielded smaller chicks at hatching that had a lower body mass index at 24 days old. Additionally, these chicks displayed lower haematocrit when body mass index was higher. Therefore, ingestion of conventional grains by parents resulted in chronic exposure to pesticide residues, even at low doses, and this had detrimental consequences on offspring. These results demonstrate a sublethal effect of pesticide residues through parental effects. The consequences of parental exposure on chicks might partly explain the decline in wild Grey partridge populations, which raises questions for avian conservation and demography if current agrosystem approaches are continued.
显示更多 [+] 显示较少 [-]Associations between polybrominated diphenyl ethers (PBDEs) levels in adipose tissues and female menstrual cycle and menstrual bleeding duration in Shantou, China
2022
Shi, Xiaoling | Wang, Xin | Peng, Lin | Chen, Yebin | Liu, Caixia | Yang, Qingtao | Wu, Kusheng
The endocrine-disrupting effects of human exposure to polybrominated diphenyl ethers (PBDEs) have been studied, but their associations with menstrual status were not clearly clarified. This study was to evaluate the associations between PBDE levels in adipose tissues and the menstrual cycle and menstrual bleeding duration alteration. A total of 298 female cases undergoing surgery were recruited from two hospitals in Shantou, China. Demographic, clinical, and pathological information were collected, and adipose tissues were obtained during mammary or abdominal surgery. Gas chromatography with mass spectrometry was used to analyze 14 PBDE congeners in the adipose samples. The associations between PBDE levels and menstrual cycle (MC) and menstrual duration (MD) were analyzed by logistic regression models, estimating odds ratios (ORs) and 95% confidence intervals (CIs). BDE-153 had the highest level in the adipose samples, followed by BDE-209, BDE-183 and BDE-47. Compared with referents, median levels of BDE-47, -71, −153, −183 were higher in women with MC > 30 days (all P < 0.05); BDE-47, -153, −183, −209 were also higher in women with MD > 5.5 days (all P < 0.05). After adjusted for age and parity, BDE-47, -71, −153, −183 were associated with prolonged MC (OR = 1.20, 1.15, 1.12, 1.11, respectively, all P < 0.05) in the logistic regression models; and BDE-47, -153, −183, −209 were associated with the prolonged MD (OR = 1.13, 1.09, 1.10, 1.11, respectively, all P < 0.05). Several individual PBDE congeners in female adipose were found associated with prolonged menstrual cycle and menstrual duration. PBDEs may influence reproductive health of women by altering menstrual status.
显示更多 [+] 显示较少 [-]New insight into transformation of tetracycline in presence of Mn(II): Oxidation versus photolysis
2022
Ouyang, Zhuozhi | Lei, Fadan | Hu, Endian | Li, Shuxing | Yao, Qian | Guo, Xuetao
Tetracycline (TC) and Mn(II) is a common antibiotic and metal ion respectively. Nevertheless, literatures involving in the effects of Mn(II) on TC transformation are still insufficient. In this study, the kinetic experiment, spectral analysis, complexation experiment and electrochemical analysis, theoretical calculation and products detection were carried out to probe into oxidation and photolysis of TC with Mn(II). Mn(II) greatly accelerated TC oxidation, preferably tending to complex with TC at O10 – O12 or O2 – O3 site. There were a TC-Mn(II)/TC-Mn(III) redox couple and electron transfer process. Conversely, Mn(II) inhibited photolysis of TC. The photolysis of excited TC could compete with energy dissipation reactions. The electron transfer and complexation reaction easily made excited TC energy transfer, thus slowing down photolysis process. During the TC transformation, the intensity of functional groups was significantly decreased. Simultaneously, the degradation pathways mainly included eight reactions. It is a very interesting and probably overlooked phenomenon, which identifies new transformation of TC with Mn(II). This study helps to further understand fate and environmental behavior of antibiotics and metal ion.
显示更多 [+] 显示较少 [-]Metagenomics highlights the impact of climate and human activities on antibiotic resistance genes in China's estuaries
2022
Zheng, Dongsheng | Yin, Guoyu | Liu, Min | Hou, Lijun | Yang, Yi | Liu, Xinran | Jiang, Yinghui | Chen, Cheng | Wu, Han
Estuarine environments faced with contaminations from coastal zones and the inland are vital sinks of antibiotic resistance genes (ARGs). However, little is known about the temporal-spatial pattern of ARGs and its predominant constraints in estuarine environments. Here, we leveraged metagenomics to investigate ARG profiles from 16 China's estuaries across 6 climate zones in dry and wet seasons, and disentangled their relationships with environmental constraints. Our results revealed that ARG abundance, richness, and diversity in dry season were higher than those in wet season, and ARG abundance exhibited an increasing trend with latitude. The prevalence of ARGs was significantly driven by human activities, mobile gene elements, microbial communities, antibiotic residuals, physicochemical properties, and climatic variables. Among which, climatic variables and human activities ranked the most important factors, contributing 44% and 36% of the total variance of observed ARGs, respectively. The most important climatic variable shaping ARGs is temperature, where increasing temperature is associated with decreased ARGs. Our results highlight that the prevalence of ARGs in estuarine environments would be co-driven by anthropogenic activities and climate, and suggest the dynamics of ARGs under future changing climate and socioeconomic development.
显示更多 [+] 显示较少 [-]Simultaneous removal of COD and NH4+-N from domestic sewage by a single-stage up-flow anaerobic biological filter based on Feammox
2022
Ma, Ding | Wang, Jin | Li, Hao | Che, Jian | Yue, Zhengbo
In recent years, Feammox has made it possible to remove NH₄⁺-N under anaerobic conditions; however, its application in practical wastewater treatment processes has not been extensively reported. In this study, an up-flow anaerobic biological filter based on limonite (Lim-UAF) was developed to facilitate long-term and stable treatment of domestic sewage. Lim-UAF achieved the highest removal efficiency of chemical oxygen demand (COD) and NH₄⁺-N at a hydraulic retention time (HRT) of 24 h (Stage II). Specifically, the COD and NH₄⁺-N content decreased from 240.8 and 30.0 mg/L to about 7.5 and 0.35 mg/L, respectively. To analyze the potential nitrogen removal mechanism, the Lim-UAF was divided into three layers according to the height of the reactor. The results showed that COD and NH₄⁺-N removal had remarkable characteristics in Lim-UAF. More than 55.0% of influent COD was removed in the lower layer (0–30 cm) of Lim-UAF, while 60.2% of NH₄⁺-N was removed in the middle layer (30–60 cm). Microbial community analysis showed that the community structure in the middle and upper layers (60–90 cm) was relatively similar, but quite different from that of the lower layer. Heterotrophic bacteria were dominant in the lower layer, whereas iron-reducing and iron-oxidizing bacteria were enriched in the upper and middle layers. The formation of secondary minerals (siderite and Fe(OH)₃) indicated that the Fe(III)/Fe(II) redox cycle occurred in Lim-UAF, which was triggered by the Feammox and NDFO processes. In summary, limonite was used to develop a single-stage wastewater treatment process for simultaneously removing organic matter and NH₄⁺-N, which has excellent application prospects in domestic sewage treatment.
显示更多 [+] 显示较少 [-]Associations between organophosphate esters concentrations and markers of liver function in US adolescents aged 12–19 years: A mixture analysis
2022
Li, Ruiqiang | Zhan, Wenqiang | Ren, Jingyi | Gao, Xian | Huang, Xin | Ma, Yuxia
Liver disease has become a growing health burden, and little is known about the impairment of liver function caused by exposure to organophosphate esters (OPEs) in adolescents aged 12–19 years in the United States. To investigate the relationship between urinary metabolites of OPEs including diphenyl phosphate (DPHP), bis(1,3-dichloro-2-propyl) phosphate (BDCPP), bis(1-chloroethyl) phosphate (BCPP), bis(2-chloroethyl) phosphate (BCEP), and dibutyl phosphate (DBUP) and liver function in US adolescents aged 12–19 years. Liver function tests (LFTs) include aspartate aminotransferase (AST), albumin (ALB), alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT), total bilirubin (TBIL), total protein (TP), and AST/ALT. Meanwhile, potential confounding and interaction effects were assessed. The study sample included 592 adolescents aged 12–19 from two consecutive NHANES cycles (2011–2012, 2013–2014). A composite statistical strategy combining traditional linear regression with advanced multi-pollutant models quantile based g-computation (QGC) and eXtreme Gradient Boosting (XGBoost) regression was used to analyze the joint effects of multiple OPEs on liver function indicators, and to describe the interaction between different OPEs in detail. 592 adolescent participants were 15 (14–17) years old, with similar numbers of males and females (304 vs. 288). The analysis results showed that (1) in the linear regression model, individual DPHP, BCEP exposure and ALP changes, BCEP and AST/ALT changes were positively associated. DPHP, BDCPP were negatively associated with TP changes. (2) The combined effects of various OPEs on ALB, ALT, ALP, GGT, TBIL, TP, and AST/ALT were statistically significant. (3) There is no potential interaction between different OPEs. Several OPEs and their combinations are closely related to the 8 LFT indicators. In addition, data suggest that exposure to OPEs in adolescents may be associated with liver damage. Due to limited evidence in the literature and potential limitations of the current study, our findings require more studies to confirm.
显示更多 [+] 显示较少 [-]Antibiotics-induced changes in intestinal bacteria result in the sensitivity of honey bee to virus
2022
Deng, Yanchun | Yang, Sa | Zhao, Hongxia | Luo, Ji | Yang, Wenchao | Hou, Chunsheng
Antibiotics are omnipresent in the environment due to their widespread use, and they have wide-ranging negative impacts on organisms. Virus resistance differs substantially between domesticated Apis mellifera and wild Apis cerana, although both are commonly raised in China. Here, we investigated whether antibiotics can increase the sensitivity of honey bees to viral infection using the Israeli acute paralysis virus (IAPV) and tetracycline as representative virus and antibiotic. Although IAPV multiplied to lower levels in A. cerana than A. mellifera, resulting in decreased mortality (P < 0.01), there was no significant difference in immune responses to viral infection between the two species. Adult worker bees (A. cerana and A. mellifera) were treated with or without tetracycline to demonstrate the prominent role of gut microbiota against viral infection, and found Lactobacillus played a vital antiviral role in A. cerana. In A. cerana but not A. mellifera, tetracycline treatment reduced clearly bee survival and increased susceptibility to IAPV infection (P < 0.01). Our findings revealed that long-term antibiotic treatment in A. mellifera had altered the native gut microbiome and promoted the sensitivity to viral infection. We highlight the effects of antibiotics exposure on resistance to microbial and viral infection.
显示更多 [+] 显示较少 [-]Simultaneous removal of heterocyclic drugs and total nitrogen from biochemical tailwater by peracetic acid/cobalt-loaded ceramsite-based denitrification biofilter
2022
Li, Tong | Jin, Lili | Zhu, Shanshan | Zhang, Xuxiang | Ren, Hongqiang | Huang, Hui
It is difficult to achieve simultaneous and efficient removal of heterocyclic drugs (HCDs) and total nitrogen (TN) in conventional denitrification biofilter (DNBF). Inspired by the effective degradation of refractory organic matter by cobalt-based advanced oxidation process and the need for in-situ upgrading of DNBF, peracetic acid (PAA)/cobalt-loaded ceramsite-based DNBF system was constructed for the first time to treat biochemical tailwater containing HCDs. Results showed that PAA/Co-DNBF had relatively high removal rates for the four HCDs with the order of CBZ > TMP > SDZ > SMX, and the optimal DNBF was H2 with 150 μg L⁻¹of PAA. Overall, TN and HCDs removal increased by 178%–455% and 2.50%–40.99% respectively. When the influent concentration of NO₃⁻-N, COD and each HCDs of 20 mg/L, 60 mg/L and 20 μg/L, below 15 mg/L of effluent TN and the highest average removal rate of SMX (67.77%) could be achieved, under HRT of 4 h in H2. More even distribution of microbial species and low acute toxicity of effluent were also achieved. More even distribution of microbial species and low acute toxicity of effluent were also achieved. In addition, high extracellular polymeric substance (EPS) content and Gordonia after the addition of PAA contributed to the degradation of HCDs. This study supplied a potentially effective strategy for the treatment of biochemical tailwater containing HCDs and provided new insight into the advance of denitrification technology.
显示更多 [+] 显示较少 [-]Effects of heavy metals stress on chicken manures composting via the perspective of microbial community feedback
2022
Chen, Xiaomeng | Du, Zhuang | Guo, Tong | Wu, Junqiu | Wang, Bo | Wei, Zimin | Jia, Liming | Kang, Kejia
Heavy metal pollution was the main risk during livestock manures composting, in which microorganisms played a vital role. However, response strategies of microbial community to heavy metals stress (HMS) remained largely unclear. Therefore, the objective of this study was to reveal the ecological adaptation and counter-effect of bacterial community under HMS during chicken manures composting, and evaluating environmental implications of HMS on composting. The degradation of organic matters (more than 6.4%) and carbohydrate (more than 19.8%) were enhanced under intense HMS, suggesting that microorganisms could quickly adapt to the HMS to ensure smooth composting. Meanwhile, HMS increased keystone nodes and strengthened significant positive correlation relationships between genera (p < 0.05), indicating that bacteria resisted HMS through cooperating during composting. In addition, different bacterial groups performed various functions to cope with HMS. Specific bacterial groups responded to HMS, and certain groups regulated bacterial networks. Therefore, bacterial community had the extraordinary potential to deal with HMS and guarantee chicken manures composting even in the presence of high concentrations of heavy metals.
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