Microbial degradation to remove residual antibiotics in wastewater is of growing interest. However, biological treatment of antibiotics may cause resistance dissemination by mutations and horizontal gene transfer (HGT) of antibiotic resistance genes (ARGs). In this study, a Mn(Ⅱ)-oxidizing bacterium (MnOB), Pseudomonas aeruginosa MQ2, simultaneously degraded antibiotics, decreased HGT, and mitigated antibiotic resistance mutation.
View Article and Find Full Text PDFIn order to understand the occurrence characteristics and ecological risks of pharmaceuticals and personal care products (PPCPs) in surface water and sediments of Hongze Lake and Gaoyou Lake in the lower reaches of the Huaihe River, 43 surface water and sediment samples from 23 sampling sites were collected, and 61 PPCPs were detected in the samples. The concentration level and spatial distribution of target PPCPs in Hongze Lake and Gaoyou Lake were analyzed, the distribution coefficient of typical PPCPs in the water/sediment system in the study area was calculated, and the ecological risk of target PPCPs was evaluated using the entropy method. The results showed that the PPCPs in surface water of Hongze Lake and Gaoyou Lake were 1.
View Article and Find Full Text PDFThe establishment of water quality criteria (WQC) for copper (Cu) was used as the basis for an ecological risk assessment of marine Cu pollution in Liaodong Bay, China. Published ecotoxicity data for Cu were obtained and supplemented with the results of acute Cu toxicity tests. The marine WQC for Cu in Liaodong Bay was developed using a species sensitivity distribution method with a safety factor of 2.
View Article and Find Full Text PDFDissemination of antibiotic resistance genes (ARGs) through natural transformation is facilitated by factors that stabilize extracellular DNA (eDNA) and that induce reactive oxygen species (ROS) that permeabilize receptor cells and upregulate transformation competence genes. In this study, we demonstrate that can mitigate this ARG dissemination pathway by removing both eDNA and ROS that make recipient cells more vulnerable to transformation. We used plasmid RP4 as source of extracellular ARGs (, , and ) and the opportunistic pathogen as receptor.
View Article and Find Full Text PDFTo investigate the impact of megacities on the chemistry of surface waters, monthly sampling and monitoring were conducted in the Chengdu section of the Minjiang and Tuojiang River basin, corresponding to the upper reaches of the Yangtze River since the spring of 2019, including the influent and effluent water samples from 57 sewage treatment plants in Chengdu. All the samples were analyzed for major ions and other water chemistry parameters, and compared with the historical data of the Minjiang and Tuojiang River. The results showed that the Chengdu surface water still presented a natural chemistry with medium-low total dissolved solids(TDS), and calcium bicarbonate chemistry type, which is the natural consequence of the weathering of carbonate rocks in the basin effected by the weathering of silicates and evaporites.
View Article and Find Full Text PDFThe rapid emergence of antibiotic resistance genes (ARGs) has become an increasingly serious threat to public health. Previous studies illustrate the antibiotic-like effect of many substances. However, whether and how commonly used or existing non-antibiotic metalloids (e.
View Article and Find Full Text PDFIn order to illuminate pollutants distribution characteristics in sediment of Shanmei Reservoir, sediment samples at 47 sampling stations were collected (include 8 column samples), and concentrations of total nitrogen, total phosphorus and organic matter in the sediment of each station were measured. C/N and the correlation of TN, TP and OM were also analyzed. Finally, pollution assessment for contaminated layer sediments was conducted.
View Article and Find Full Text PDFThis study aims to evaluate the carcinogenic risk of PAHs in the drinking water of counties along the Huai River in China and study their associations with high cancer incidence in local population. We investigated 20 villages with high cancer incidence rates as the risk group and 20 villages with low rates as the control group. Water samples from each village were collected in the winter and summer seasons to analyze the concentrations of 16 PAHs.
View Article and Find Full Text PDFIn order to clarify the distribution characteristics and risk levels of heavy metals in typical drinking water sources of towns in Dongjiang River Basin, several regular water quality indexes as well as concentrations of Fe, Cu, Mn, Zn, As, Cr, Hg, Pb and Cd were analyzed in the 45 random water samples of 9 towns in the study area. The risk assessment was conducted according to different drinking water types using the environmental health risk assessment model recommended by U. S.
View Article and Find Full Text PDFThe temporal changes of total dissolved solid concentrations were analyzed according to the investigations and regular monitoring data in the Inner Mongolia-Xinjiang plateau. The result showed that the salinization process in the Inner Mongolia-Xinjiang plateau became strong. Integrated regression equation indicated that, the environmental physical and chemical factors affecting chlorophyll-a were total phosphorus and TDS.
View Article and Find Full Text PDFIt is important precondition to enact viable lake nutrients control standard for lake control and management. Now China is shortage of study on nutrients control standard considering of the regional and nutrient difference. In this paper, five-step method for nutrient control standard is built following the principle of commonality, possibility and practicability.
View Article and Find Full Text PDFEffects of chitosan on a submersed plant, Hydrilla verticillata, were investigated. Results indicated that H. verticillata could prevent ultrastructure phytotoxicities and oxidativereaction from polluted water with high chemical oxygen demand (COD).
View Article and Find Full Text PDFYing Yong Sheng Tai Xue Bao
February 2007
In this paper, submersed plant Hydrilla verticillata was cultivated in a 1/10 Hoagland culture medium added with different concentration NH4 + -N (0, 0. 5, 2. 0, 4.
View Article and Find Full Text PDFCombined pollution is more ubiquitous than the single pollution in water and soil environment. Iodine method was used to study the effects of both single and combined pollution of Cd and NH4+ on Hydrilla verticillata and Myriophyllurn spicatum. Results came out that H.
View Article and Find Full Text PDFEquilibrium sorption isotherms for Cu2+ onto Hydrilla verticillata Royle and Myriophyllum spicatum were studied. Both methods of linear and non-linear fitting were applied to describe the sorption isotherms, and their applicability were analyzed and compared. The results were: (1) The applicability of simulated equation can't be compared only by R2 and chi2 when equilibrium sorption model was used to quantify and contrast the performance of different biosorbents.
View Article and Find Full Text PDFIn recent years cyanobacteria blooms have become a severe problem in Taihu Lake, a large shallow eutrophic lake in China. Microcystins produced by certain genera of cyanobacteria can affect public health in this area because of their acute and chronic toxic effects. In this study, samples of cyanobacteria were collected and extracted by two solvent systems.
View Article and Find Full Text PDFJ Environ Sci (China)
September 2006
The potential use of Myriophyllum spicatum L. biomass as a biosorbent for the removal of copper(II) from aqueous solution was investigated in laboratory condition. The sorption experiments were undertaken to obtain copper(II) biosorption properties of M.
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