ENVIRONMENT INTERNATIONAL
·
2023
·
IF 11.8
Feiyang Xia,Qian Tan,Haiguang Qin,Dunqiu Wang,Yanpeng Cai,Jun Zhang
In rivers, riverbeds are considered to have dual properties as a short-term sink and a source of further mobilization for microplastics. To better understand the sources, storage, and fate of microplastics in river systems, this study quantified the formation of microplastic hotspots in riverbeds and seasonal variations in microplastic inventories in riverbeds, especially for small-sized microplastics (<330 µm), with a fluorescence-based protocol. This study provides first-hand measured evidence for the sequestration of microplastics in the riverbed under low-flow conditions and its export from the riverbed under high-flow conditions. The results show that riverbeds in urban areas are still hotspots for microplastic pollution and that high inputs of urban microplastics control microplastic load in its downstream areas. Seasonal rainfall exported 34.86 % (equivalent to 4.34 × 10 11 items/8.57 t) of microplastic pollution from the riverbed, and its removal capacity may be related to the rainfall intensity. Wider riverbeds are conducive to the formation of microplastic hotspots due to the flow slow down. Most importantly, rainfall-driven scouring of the riverbed can enhance the pollution of small-sized microplastics in the riverbed, especially the smallest-size microplastics (<100 µm). Therefore, this study not only contributes reliable information about the sequestration and export of microplastics in the riverbed, but also provides a possible mechanism to explain the lack of small-sized microplastics (<330 µm) in the ocean.
研究领域:
环境科学
·
生态学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2018
·
IF 4.61
Haidong Zhou,Xiaojing Liu,Xiaomeng Chen,Tianqi Ying,Zhenxi Ying
The investigations on their variation and distribution of 13 called waste-water marking pharmaceuticals (WWMPs) were conducted under 4 hydrophyte conditions (without plants, with submerged aquatic plant ( Myriophyllum verticillatum L.), emergent aquatic plant cattail ( Typha orientalis Presl) and floating aquatic plant ( Lemna minor L.)) in a simulated urban river system. By the calculation of mass balance, the quantitative distribution of WWMPs in water phase, sediment and plant tissues was identified, and the overall removal efficiencies of target pharmaceuticals in the whole system could be determined. Without plants, high persistence of atenolol (ATL) (97.7%), carbamazepine (CBM) (102.8%), clofibric acid (CLF) (101.8%) and ibuprofen (IBU) (80.9%) was detected in water phase, while triclosan (TCS) (53.5%) displayed strong adsorption affinity in sediment. The removal under the planted conditions was considerably raised, compared with no plant condition for most WWMPs. However, TCS did not show obvious differences among the hydrophyte conditions due to its strong adsorption affinity and high hydrophobicity . The relatively higher removal was found for the hydrophilic (logK ow < 1) or moderately hydrophobic (1 < logK ow < 3) pharmaceuticals with submerged and emergent aquatic plants. The highly hydrophobic pharmaceuticals (logK ow > 4.0) did not show significant differences among the whole tests in sediment. Mass balance calculation displayed the removal of CBM (5.6%–13.6%), CLF (4.0%–17.8%) and caffeine (8.4%–17.2%) through the plant uptake was relatively higher. For the rest WWMPs, only small parts (<6.0%) of the initial concentrations were found in plant tissues. The higher removal efficiencies of most WWMPs under the planted conditions indicated that aquatic plants indeed played an important role in the removal of WWMPs although the direct uptakes might not be a dominant pathway to the overall removal of WWMPs. Besides, the floating aquatic plant removed most WWMPs from the water phase efficiently. In contrast, submerged and emergent aquatic plants could effectively remove them in sediment.
研究领域:
环境科学
·
生态学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
WATER RESEARCH
·
2024
·
IF 11.4
Huan-yu Tao,Jianghong Shi,Jiawei Zhang,Hui Ge,Xiaowei Liu,Xiao-yan Li
The city-river-reservoir system is an important system for safeguarding drinking water. Phthalic acid esters (PAEs) are emerging contaminants in drinking water sources that are gaining attention, and they could pose risks to human health and aquatic organisms. In this study, field studies that lasted four years were conducted to analyze the concentrations, spatial-temporal distribution, and removal effects of six PAEs. The total concentrations of the Σ6PAEs in the water and sediment samples were 0.2–7.4 μg L −1 (mean: 1.3 μg L −1 ) and 9.2–9594.1 ng g −1 (mean: 847.5 ng g −1 ), respectively. Di-n-butyl phthalate (DBP) and, bis(2-ethylhexyl) phthalate (DEHP) were the predominant congeners, accounting for 57.2 % in the water samples and 94.1 % in the sediment samples. The urban area contributed 72 % of the PAEs in the system. A significant removal effect of PAEs was observed in the wetland, with a removal rate of 40.2 %. The partitioning of PAEs between the water and sediment was attributed to the removal of dimethyl phthalate and diethyl phthalate that occurred during the water phase, while the removal of DBP and DEHP primarily occurred during the sediment phase. The ecological risk calculation based on the sensitivity distribution model indicated that DBP (HQ water = 0.19, HQ sediment = 0.46) and DEHP (HQ water = 0.20, HQ sediment = 0.13) possessed moderate risks according to some water and sediment samples. The ecological projects were verified to be effective engineering strategies to reduce ecological risk in the drinking water source.
研究领域:
环境科学
·
生态学
·
公共卫生
✓ 已验证
产品关联
DOI
PubMed
高影响因子
International Journal of Environmental Science and Technology
·
2018
·Vol. 16
·期 10
·5669-5684
·
IF 2.037
Zhou H.,Chen X.,Ying T.,Xuan Y.,Wangjin Y.,Liu X.
Thirteen wastewater-marking pharmaceuticals were selected to explore their variations and behavior under hydrodynamic conditions in urban river systems. Four flow velocities were set, i.e., 0 cm/s for static condition, and 5, 10 and 20 cm/s for dynamic conditions. In the water phase, most of target compounds emerged big fluctuations between static and dynamic conditions. The lower concentrations were detected in the dynamic conditions. However, carbamazepine had minimum relative change during the whole 15-day tests with at least 85% of the initial concentration remaining. In the sediment, the concentrations of most pharmaceuticals in the dynamic conditions were higher than in the static condition, whereas carbamazepine showed big fluctuation in both static and dynamic conditions. With the change of the flow velocities, all target pharmaceuticals showed obviously different variation tendencies mainly due to the changes of environmental parameters, such as turbidity, dissolved matters, microbial biomass, and suspended particulates. In addition, five metabolites were selected to further investigate the transformation of diclofenac and carbamazepine with different flow velocities in the water phase. More diclofenac were transformed into 4-Hydroxy diclofenac in the water phase in the dynamic conditions. Moreover, in the case of a set flow velocity, the concentrations of some pharmaceuticals changed remarkably between the straight and turning channels of an urban river system. Overall, hydrodynamic conditions showed significant influences on the levels of target compounds in the aquatic environment and, therefore, could be taken into account in the risk assessment and control of these compounds.
研究领域:
环境科学
·
生态学
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL TECHNOLOGY
·
2015
·
IF 1.56
Dickson Y. S. Yan,Tongzhou Liu,Irene M. C. Lo
The technical feasibility, environmental discharges and cost-performance of urban river contaminated sediment treatment with ex situ advanced oxidation processes were evaluated for the purpose of achieving an ideal treatment goal (for marine disposal) and a cost-performance treatment goal (for beneficially reusing as a filling material). Sediment samples were collected from a river located in southern China. To achieve the ideal treatment goal, sequential treatments (Fenton's reaction + activated persulphate oxidation) were carried out. One-step Fenton's reaction was applied to achieve the cost-performance treatment goal. The resulting effluent was treated and discharged, and sludge generated in wastewater treatment was characterized. The resources input throughout the treatment processes were recorded for cost estimation. After the treatment designed for achieving the ideal treatment goal, most pollutants fulfilled the treatment goal except Pb, Cd, Hg and Ag, probably because these four metals were present mainly in stable fractions of the sediment. The cost-performance treatment goal was achieved in view of low pollutant contents in the toxicity characteristic leaching procedure leachate of treated sediment. The cost for achieving the cost-performance treatment goal is much less than that for achieving the ideal treatment goal. The major cost difference is attributed to chemical cost. Stringent sediment treatment goals based on existing standards would lead to massive chemical use, complex treatment and hence huge cost. A simpler treatment with fewer chemicals is adequate for sediment beneficially reused as a filling material, and is economically more advantageous than handling sediment for marine disposal.
研究领域:
环境科学
·
水处理工程
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2023
·
IF 13.6
Yuxuan Liu,Bei Su,Hongxin Mu,Yu Zhang,Ling Chen,Bing Wu
Wastewater discharge is considered to be one of the anthropogenic factors affecting the water quality of urban rivers. The source and composition of wastewater are complex and diverse, and it is difficult to evaluate its effect on water quality and ecological health of receiving waters. Environmental DNA method can determine all species living in waters by examining DNA sequences, reflecting the impact of water quality changes on aquatic systems. In this study, water samples from two urban rivers were collected in dry and wet seasons, and the composition of pollutants was investigated by nontarget screening. Based on the pollutant composition, compound toxicity prediction and concentration addition model were used to predict the toxicity changes of pollutants in the urban rivers. More than 1500 suspect organic pollutants were nontarget screened, and silafluofen was found to be a major toxicity contributor. Environmental DNA analysis was combined with water quality measure and pollutant toxicity prediction to reveal the effects of pollutants from different sources on aquatic ecosystems . Fish diversity was negatively correlated with the mixed toxicity of organic pollutants, suggesting potential ecological risk in these two urban rivers. Our study developed a water quality assessment method based on pollutant composition and toxicity, and the potential risk of nonpoint source pollutants on aquatic ecosystems should not be neglected.
研究领域:
生态学
·
环境科学
·
毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
WATER RESEARCH
·
2022
·
IF 13.4
Ruilong Li,Longji Zhu,Yijin Wang,Yong-Guan Zhu
Microplastics (MPs) are emerging as anthropogenic vectors for the colonization and transportation of microbial communities in aquatic ecosystems. However, the composition of the microbiome and its environmental risk on field MPs at watershed scale has rarely been explored. Here, geographical distributions of microbiome, antibiotic resistance genes (ARGs) and virulence factors (VFs) on field MPs at watershed scale were characterized and their potential environmental risks were evaluated based on the data from metagenomic analyzes. The succession of microbial communities on MPs was observed along the watershed, and some ARGs and VFs were significantly enriched on MPs in urban region in comparison with rural region. Potential environmental risk of MPs conducted by Projection Pursuit Regression model in midstream (peri-urban region) and downstream (urban region) were significantly higher than that in upstream (rural region), and exhibit close relationships with MPs concentration and water velocity. Furthermore, our source tracking results demonstrated that the microbiome, ARGs and VFs in urban region MPs were largely derived from rural region MPs. Our results caution us that special attention should be paid to the risks posed by MPs in urban water bodies, and highlight the threat of MPs from rural upstream areas.
研究领域:
环境科学
·
微生物学
·
生态学
·
基因组学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）