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1.
Sci Total Environ ; 806(Pt 4): 151476, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34742952

RESUMO

Anthropogenic activities have inevitably impacted riverine ecosystems, yet their overall contribution to the assemblage of bacterial communities at a large river basin scale remains unclear. In this study, 16S amplicon sequencing was implemented to investigate the bacterial ecosystems in paired water and sediment of North River and West River basins in South China., which contains various anthropogenic environments (e.g., rural/urban area, mining area and livestock area). Subsequently, the links between bacterial community and various types of emerging pollutants in river water were analyzed. The results show that the bacterial assemblage of water and sediment had their own properties that the bacterial community of sediment were mainly affected by seasonal properties, while the bacterial community of water were affected by both seasons and anthropogenic activities. Therein, the aquatic bacterial compositions and abundances were driven by changes in temperature, dissolved oxygen and the emerging pollutants. The dominant phyla Proteobacteria and Firmicutes exhibited adaptability to the mining-affected regions, therein many clades (e.g., Beijerinckiaceae, Acetobacteraceae and Mycobacteriaceae) were also prevalent in the livestock-affected and densely-populated regions. In addition, these two phyla presented associations to the antibiotic resistance in water. The levels of antibiotics, relative antibiotic resistance gens (ARGs) and non-antibiotic pharmaceuticals (NAPs) were closely related to bacterial community composition, diversity and functional diversity, indicating their drive in shifting bacterial communities. Collectively, this work provides a basis for understanding the contribution of anthropogenic activities in shifting bacterial community at a large river basin scale. Further, the results provide new insights for expansion of ecological assessment.


Assuntos
Ecossistema , Rios , Bactérias/genética , China , Estações do Ano
2.
Chemosphere ; : 133174, 2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34871619

RESUMO

Wide use of various chemicals has resulted in water pollution, which has become a global environmental concern. So far limited information is available on what chemicals in our water. Here we investigated the occurrence and profiles of organic chemicals in the North River, South China by applying non-target screening analysis with high resolution mass spectrometry. A total of 402 organic chemicals belonging to eleven categories were identified in the North River, with notable presence of industrial chemicals, pharmaceuticals and pesticides. Among these detected chemicals, over half of the tentatively identified compounds were rarely reported in the surface water, with a few compounds, e.g., sisomicin, simeton, 2-methyl-4,6-dinitrophenol, xanthurenic acid and indole-3-carboxylic acid that have never been documented in the North River before, while the metabolites like 4-acetamidoantipyrine were also observed. The maximum concentration of the identified chemicals in the North River was above 300 ng/L (Sulfamonomethoxine). Principle component analysis results of the obtained dataset showed significant seasonal distribution, which could be linked to variations in wastewater discharge, river dilution and anthropogenic activities such as pesticide spray. Agricultural activities in the upper reaches led to detection of various pesticides in the river basin, especially in the wet season. The findings from this study demonstrated the widespread presence of chemicals in our waterway, and further retrospective analysis would reveal more information about chemicals of emerging concern.

3.
Sci Total Environ ; : 152042, 2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-34856250

RESUMO

Increasing use of feed and medicine in mariculture could cause negative environmental impacts such as habitat modification, microbial disease development and antibiotic resistance. Here we investigated contamination of antibiotics and antibiotic resistance genes (ARGs), and composition of microbial community in grouper mariculture systems in Hainan province, China. Results showed detection of various antibiotic residues with the dominance of fluoroquinolones and tetracyclines in the six grouper cultivation systems. The concentrations of the detected antibiotics in the grouper mariculture water were significantly higher than those in the original seawater. Some of the detected antibiotics such as enrofloxacin, ciprofloxacin, ofloxacin, oxytetracycline and erythromycin in the mariculture water and/or sediment would pose high resistance selection risks. Sulfonamides resistance genes sul1 and sul2 were found to be predominant in water and sediment, while tetracycline resistance genes were prevalent in fish gill and gut. The dominant bacterial phyla in water and sediments were Bacteroides, Actinomycetes, and Proteobacteria, while the dominant ones in fish gill and gut were the Proteobacteria. Genera of Vibrio and Mycobacterium in the core microbiota were important zoonotic pathogens, and there was a significant positive correlation between Vibrio and ARGs. Phyla of Proteobacteria, Actinomyces, and Cyanobacteria were positively correlated to ARGs, indicating that these microorganisms are potential hosts of ARGs. The putative functions of microbiome related to antibiotic resistance and human diseases were significantly higher in fish than in the mariculture environment. This study suggests that mariculture system is a reservoir of ARGs, and the use of antibiotics in mariculture could induce the increase of antibiotic resistance and the prevalence of opportunistic pathogens.

4.
Sci Total Environ ; 808: 151866, 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34822902

RESUMO

Drinking water quality and safety are very important in protecting human health. Chemical contaminants in drinking water system have become an increasing concern. Our knowledge about what chemicals are present in drinking water is still limited. Here we screened chemicals of emerging concern in a conventional drinking water system based on suspect, non-target screening and target analysis, and assessed their variations in different seasons and different treatment units. Overall, 720 chemicals were identified with HRMS databases from the suspect and non-target screening and 48 chemicals in five categories were further confirmed with the high confidence level, with predominance of pharmaceuticals and personal care products (PPCPs) and pesticides. Four compounds are newly found in aquatic environment with no literature or chemical occurrence data record. Temporal variations and variable removals were observed for these chemicals in the system. Target analysis of 110 PPCPs showed detection of 21, 19 and 22 compounds in the drinking water treatment plant with a concentration range of 0.11-844 ng/L in the three seasons, but only 8, 9 and 15 compounds detected in tap water (0.16-32.5 ng/L). The variations of the detected chemicals were less obvious in tap water, with most having concentrations below 2 ng/L. The results indicated efficient removal for most PPCPs in the drinking water system. The findings from this study demonstrated the strong capability of combined non-target screening and target analysis in identifying and assessing various organic chemicals in drinking water system.

5.
Innovation (N Y) ; 2(4): 100164, 2021 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-34622241

RESUMO

Multiple systematic reviews on greenspace and health outcomes exist, but the overall evidence base remains unclear. Therefore, we performed an umbrella review to collect and appraise all relevant systematic reviews of epidemiological studies on greenness exposure and health. We searched PubMed, Embase, and Web of Science from inception to June 28, 2021, and screened references of relevant articles. Systematic reviews with or without meta-analyses of epidemiological studies that examined the associations of greenness with any health outcome were included. Two independent investigators performed study selection and data extraction. We also evaluated the methodological quality of the included systematic reviews using the "Assessing the Methodological Quality of Systematic Reviews 2" checklist. A total of 40 systematic reviews and meta-analyses were included, of which most were cross-sectional studies conducted in high-income countries. Greenspace exposure was estimated with various objective and subjective parameters. Beneficial associations of greenspace with all-cause and stroke-specific mortality, CVD morbidity, cardiometabolic factors, mental health, low birth weight, physical activity, sleep quality, and urban crime were observed. No consistent associations between greenspace and other health outcomes (e.g., cancers) were observed. Most of the included systematic reviews and meta-analyses had one or more limitations in methodology. Our findings provide supportive evidence regarding the beneficial effects of greenspace exposure on some aspects of human health. However, the credibility of such evidence was compromised by methodological limitations. Better performed systematic reviews and meta-analyses as well as longitudinal designed primary studies are needed to validate this conclusion.

6.
Sci Total Environ ; 798: 149299, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34332385

RESUMO

The extensive usage of organic ultraviolet filters (UV filters) and benzothiazoles (BTs) has caused continuous and widespread pollution in the aquatic environment. This study investigated the occurrence of nine organic UV filters and eight BTs in the surface water and sediment of two major drinking water source rivers in the Pearl River Basin (PRB). The detection frequencies of six organic UV filters and seven BTs were above 50% in surface water, while eight target compounds were as high as 100%. Composition profiles revealed that 2-Hydroxybenzothiazole (2-OH-BTH, 1112 ng/L) and 2-Mercaptobenzothiazole (2-SH-BTH, 426.3 ng/L) were the predominant compounds in surface water, while Octyl 4-methoxycinnamate (OMC, maximum concentration, 68.3 ng/g) and UV-329 (18.8 ng/g) were predominant in sediment. Significant positive correlations were observed between water quality parameters (temperature, total phosphorus (TP) and total nitrogen (TN)) and organic UV filters (UV-327 and UV-P), indicating the domestic discharge. The calculated annual flux of targets compounds indicated that West River (WR) promoted more BTs and UV filters to the PRB than North River (NR) (BTs: WR22, 88,517 kg/year; NR13, 15,660 kg/year; UV filters: WR22, 28,332 kg/year; NR13, 1128 kg/year). Significant relationship between the Gross Domestic Product (GDP) and annual flux of BTs (R2 = 0.96, p < 0.001), and UV filters (R2 = 0.88, p < 0.001) in the rivers were found by regression analysis. UV-329 was detected with medium risk (RQ > 0.1) in all WR surface water samples, and 2-SH-BTH was detected with high risk (RQ > 1) in half of the WR sediment samples. This study provides the first time reports on the organic UV filters and BTs in two major rivers in the Pearl River Basin, and further showed that these two types of contaminants are ubiquitous and with potential risks in surface water and sediment of PRB.


Assuntos
Rios , Poluentes Químicos da Água , Benzotiazóis , China , Monitoramento Ambiental , Água , Poluentes Químicos da Água/análise
7.
Chemosphere ; 284: 131546, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34323804

RESUMO

Emerging organic contaminants (e.g., active pharmaceutical ingredients and personal care products ingredients) are ubiquitous in the environment and potentially harmful to ecosystems, have gained increasing public attention worldwide. Nevertheless, there is a scarcity of data on these contaminants in Africa. In this study, various types of water samples (wastewater, surface water and tap water) collected from Lagos, Nigeria were analyzed for these chemicals by both target and non-target analysis on an UHPLC-Orbitrap-MS/MS. In total, 109 compounds were identified by non-target screening using the online database mzCloud. Level 1 identification confidence was achieved for 13 compounds for which reference standards were available and level 2 was achieved for the rest. In the quantitative analysis, 18 of 38 target compounds were detected, including the parent compounds and their metabolites. Acetaminophen, sulfamethoxazole, acesulfame, and caffeine were detected in all samples with their highest concentrations at 8000, 5300, 16, and 7700 µg/L in wastewater, 140000, 3300, 7.7, and 12000 µg/L in surface water, and 66, 62, 0.17 and 1000 µg/L in tap water, respectively. The occurrence of psychoactive substances, anticancer treatments, antiretrovirals, antihypertensives, antidiabetics and their metabolites were reported in Nigeria for the first time. These results indicate poor wastewater treatment and management in Nigeria, and provide a preliminary profile of organic contaminants occurring in Nigerian waters. The findings from this study urge more future research on chemical pollution in the aquatic environments in Nigeria.


Assuntos
Preparações Farmacêuticas , Poluentes Químicos da Água , Ecossistema , Monitoramento Ambiental , Nigéria , Compostos Orgânicos , Espectrometria de Massas em Tandem , Águas Residuárias , Poluentes Químicos da Água/análise
8.
Chemosphere ; 283: 131301, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34182652

RESUMO

Poly- and perfluoroalkyl substances (PFASs) are contaminants of global concern. Studies in Pearl River, south China have focused on the delta area, while the upstream contributions are unclear. Here, we systematically investigated the fate, trends and potential sources of 57 PFASs in river water, sediment and fish of the North and West Rivers of the Pearl River system. Perfluorooctanoic acid (PFOA), Perfluorooctanesulfonic acid (PFOS) and 6:2 chlorinated polyfluoroalkyl ether sulfonate (6:2Cl-PFESA) were frequently found compounds in waters, sediments and fish, suggesting their wide usage in this area and potential for bioaccumulation. Waters showed a higher ∑PFASs in the wet season compared to the dry season, but sediments did not. The North River contributed higher PFAS loads to the Pearl River Delta. Our results also reflect the current shift in PFAS usage from legacy substances to alternatives. This study, for the first time, reports data on PFASs in two upstream rivers of the Pearl River and on alternative PFASs such as PFESA in this area, which can better the understanding of their use, fate, risk assessment and further controls and management.


Assuntos
Fluorcarbonetos , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Fluorcarbonetos/análise , Água Doce , Rios , Poluentes Químicos da Água/análise
9.
Environ Int ; 155: 106594, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33940395

RESUMO

Antibiotics contamination is an emerging environmental concern, owing to its potential risks to ecosystems and human health. Microalgae-based technology has been widely reported as a promising alternative to conventional wastewater treatment, since it is a solar-power driven, ecologically friendly, cost-effective, and sustainable reclamation strategy. This review provides fundamental insights into the major mechanisms underpinning microalgae-based antibiotics removal, including bioadsorption, bioaccumulation, and biodegradation. The critical role of extracellular polymeric substances on bioadsorption and extracellular biodegradation of antibiotics are also covered. Moreover, this review sheds light on the important factors affecting the removal of antibiotics by microalgae, and summarizes several novel approaches to improve the removal efficiency, including acclimation, co-metabolism and microbial consortium. Besides, hybrid systems (such as, microalgae-based technologies combined with the conventional activated sludge, advanced oxidation processes, constructed wetlands, and microbial fuel cells), and genetic engineering are also recommended, which will be feasible for enhanced removal of antibiotics. Finally, this review also highlights the need for further studies aimed at optimizing microalgae-based technology, with emphasis on improving performance and expanding its application in large-scale settings, especially in terms of technical, environmental-friendly and economically competitiveness. Overall, this review summarizes current understanding on microalgae-based technologies for removal of antibiotics and outlines future research directions.


Assuntos
Microalgas , Antibacterianos , Biodegradação Ambiental , Ecossistema , Humanos , Tecnologia , Águas Residuárias
10.
Bull Environ Contam Toxicol ; 106(4): 594-599, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33570674

RESUMO

Dydrogesterone (DDG) acts on the reproduction but also affects the functioning of non-reproductive system. So far, the knowledge about other effects of DDG remains limited. Here we investigated the effects of DDG on the transcription of genes in innate immune and coagulation cascade in zebrafish embryos. The zebrafish embryos were exposed to DDG at 49.0, 527 and 5890 ng L- 1 for 144 hour post fertilization (hpf). The results showed that DDG significantly decreased the transcription of marker genes (e.g. tnfa, il8 and cc-chem) involved in the innate immune response at environmental concentrations. Moreover, DDG also down-regulated the transcription of genes in coagulation cascade (e.g. fga, fgb, fgg and f2). These results indicated that DDG had potential effects on the innate immune and coagulation cascade functions in the early life zebrafish, thus further affecting fish growth and health.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Didrogesterona , Embrião não Mamífero , Imunidade Inata , Reprodução
11.
Ecotoxicol Environ Saf ; 208: 111629, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396149

RESUMO

As an alternative to volatile organic solvents, ionic liquids (ILs) are known as "green solvents", and widely used in industrial applications. However, due to their high solubility and stability, ILs have tendency to persist in the water environment, thus having potential negative impacts on the aquatic ecosystem. For assessing the environmental risks of ILs, a fundamental understanding of the toxic effects and mechanisms of ILs is needed. Here we evaluated the cytotoxicity of 1-methyl-3-decylimidazolium chloride ([C10mim]Cl) and elucidated the main toxic mechanism of [C10mim]Cl in human cervical carcinoma (Hela) cells. Microstructural analysis revealed that [C10mim]Cl exposure caused the cell membrane breakage, swollen and vacuolated mitochondria, and spherical cytoskeletal structure. Cytotoxicity assays found that [C10mim]Cl exposure increased ROS production, decreased mitochondrial membrane potential, induced cell apoptosis and cell cycle arrest. These results indicated that [C10mim]Cl could induce damage to cellular membrane structure, affect the integrity of cell ultrastructure, cause the oxidative damage and ultimately lead to the inhibition of cell proliferation. Moreover, alterations of biochemical information including the increased ratios of unsaturated fatty acid and carbonyl groups to lipid, and lipid to protein, and the decreased ratios of Amide I to Amide II, and α-helix to ß-sheet were observed in [C10mim]Cl treated cells, suggesting that [C10mim]Cl could affect the structure of membrane lipid alkyl chain and cell membrane fluidity, promote the lipid peroxidation and alter the protein secondary structure. The findings from this work demonstrated that membrane structure is the key target, and membrane damage is involved in [C10mim]Cl induced cytotoxicity.


Assuntos
Substâncias Perigosas/toxicidade , Líquidos Iônicos/toxicidade , Membrana Celular/efeitos dos fármacos , Ecossistema , Células HeLa , Humanos , Imidazolinas/toxicidade , Mitocôndrias , Estrutura Secundária de Proteína , Solventes
12.
Chemosphere ; 253: 126722, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32289608

RESUMO

Levofloxacin (LEV) and sulfamethoxazole (SMX) are two extensively used antibiotics. Most investigations have been concentrated on the toxic effects of antibiotics on algal species evaluated with traditional ecotoxicological endpoints; however, limited information is available on the alterations in biomolecules induced by antibiotics. Here we investigated alterations in the structure and function of biomolecules to a model species Pseudokirchneriella subcapitata following exposure of LEV and SMX by applying Fourier transform infrared spectroscopy (FTIR). The growth inhibition tests revealed that both LEV and SMX had negative effects on algal growth, while SMX was found to be more toxic to P. subcapitata than LEV. Based on the FTIR analysis, alterations in the structure, composition and function of lipids and proteins were observed on microalgal cells, which were correlated with the dosage of LEV and SMX. As a result of lipid peroxidation induced by LEV and SMX, an increase in the lipid/protein ratio and decrease in the ratios of CH2/lipid, CH3/lipid, carbonyl ester/lipid and olefinic = CH/lipid were observed in all treatment groups with respect to the reference control. Moreover, alterations in the composition and secondary structure of proteins were also observed in accompany with a decrease in the Amide I/Amide II ratio and an increase of the loose ß-sheet structure protein. LEV caused an elevated level of lipid peroxidation, while SMX induced a more obvious protein aggregation. The findings from this study showed that FTIR could reveal the toxic mechanism of these two antibiotics to algae at the biochemical level by linking alterations in biomolecules to biochemical dynamics and function.


Assuntos
Antibacterianos/toxicidade , Levofloxacino/toxicidade , Microalgas/efeitos dos fármacos , Sulfametoxazol/toxicidade , Ecotoxicologia , Peroxidação de Lipídeos/efeitos dos fármacos , Lipídeos/química , Estrutura Secundária de Proteína , Proteínas , Espectroscopia de Infravermelho com Transformada de Fourier
13.
Water Res ; 175: 115656, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32145399

RESUMO

Microalgae-mediated biodegradation of antibiotics has recently gained increased attention from international scientific community. However, limited information is available regarding microalgae-mediated biodegradation of SMX in a co-metabolic system. Here we investigated the biodegradation of sulfamethoxazole (SMX) by five algal species (Pseudokirchneriella subcapitata, Scenedesmus quadricauda, Scenedesmus obliquus, Scenedesmus acuminatus and Chlorella pyrenoidosa), and its transformation pathways by C. pyrenoidosa in a sodium acetate (3 mM) co-metabolic system. The results showed that the highest SMX dissipation (14.9%) was detected by C. pyrenoidosa after 11 days of cultivation among the five tested algal species in the absence of other carbon sources. The addition of sodium acetate (0-8 mM) significantly enhanced the dissipation efficiency of SMX (0.4 µM) from 6.05% to 99.3% by C. pyrenoidosa after 5 days of cultivation, and the dissipation of SMX followed the first-order kinetic model with apparent rate constants (k) ranging from 0.0107 to 0.9811 d-1. Based on the results of mass balance analysis, biodegradation by C. pyrenoidosa was the main mechanism for the dissipation of SMX in the culture medium. Fifteen phase I and phase II metabolites were identified, and subsequently the transformation pathway was proposed, including oxidation, hydroxylation, formylation and side chain breakdown, as well as pterin-related conjugation. The majority of metabolites of SMX were only observed in the culture medium and varied with cultivation time. The findings of the present study showed effective co-metabolism of a sulfonamide by microalgae, and it may be applied in the aquatic environment remediation and wastewater treatment in the future.


Assuntos
Chlorella , Microalgas , Scenedesmus , Água Doce , Sulfametoxazol
14.
Environ Int ; 137: 105552, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32059144

RESUMO

Swine farm wastewaters (SFWs) are generally discharged either directly into nearby rivers or into fish ponds as a source of fertilizer/food for aquaculture in China. SFWs contain various contaminants including steroid hormones. However, there is an extreme paucity of data on their effects in fish populations. Here we investigated the endocrine disrupting effects of SFWs in G. affinis from 2 rivers (7 sites) and 2 fish ponds (2 sites) receiving SFWs and a reference site in Guangdong Province, China. In this study, a total number of 3078 adult western mosquitofish (Gambusia affinis) were collected and the sex ratio was determined. In addition, secondary sexual characteristics were examined and the transcriptional levels of target genes were analyzed. The results showed the mosquitofish populations had a significant increase in male-to-female ratio from 7 sites (including 2 fish ponds) among the 9 sampling sites. The hemal spines of females were masculinized at most sites while the hemal spines of males were feminized at approximately half of the sites (including 2 fish ponds). Significant reduction in vitellogenin (Vtg) mRNA expression was observed in females from 2 sites (including RS7) while elevated Vtg mRNA expression was noticed in males from 2 sites along the rivers (including RS7). Redundancy analysis showed that androgens in the water samples were closely related with male-to-female ratio in the mosquitofish populations and the masculinized hemal spines of females. The findings from this study demonstrated that discharge of SFWs could result in occurrence of both masculinized females and feminized males in mosquitofish population.


Assuntos
Ciprinodontiformes , Disruptores Endócrinos/toxicidade , Sistema Endócrino , Águas Residuárias , Poluentes Químicos da Água , Animais , China , Ecossistema , Sistema Endócrino/efeitos dos fármacos , Feminino , Masculino , Suínos , Poluentes Químicos da Água/toxicidade
15.
Environ Pollut ; 260: 113996, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31991359

RESUMO

Per-and polyfluoroalkyl substances (PFASs) are a group of chemicals with a wide range of industrial and commercial applications, but little is known about the contamination of PFASs in groundwater and their linkage to surface water. Here we investigated the occurrence of PFASs in groundwater and surface water at the Maozhou River basin in order to understand their contamination profiles and potential health risks. The results showed that total PFASs concentrations ranged from 9.9 to 592.2 ng/L, 50.2-339.9 ng/L and 3.7-74.3 ng/g in groundwater, river water and sediment, respectively. The detection frequencies of C4-C8 chains (C4-C8) PFASs were higher than C9-C14 chains PFASs in the river and groundwater. Statistical analysis showed an obvious correlation between the major contaminants in the river and those in the groundwater, indicating the potential linkage of PFASs in the groundwater to the surface water. The wastewater indicator found in groundwater suggested domestic wastewater was only one of the source for the PFASs in the river and groundwater of Maozhou River basin. Moreover, human health risk assessment showed low risks from the PFASs to the residents by drinking groundwater.


Assuntos
Fluorcarbonetos , Água Subterrânea , Poluentes Químicos da Água , Exposição Ambiental/estatística & dados numéricos , Monitoramento Ambiental , Indicadores Básicos de Saúde , Humanos , Rios
16.
Chemosphere ; 246: 125771, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31918091

RESUMO

Chemical pollution in the plastic debris is an increasing global concern as most pollutants might transfer from the environment to living organisms via plastic debris. In this study, biocides in the plastic debris floating on the surface water of the Pearl River system were investigated. The abundances of large plastic debris and microplastics in the surface water were 0.07 ± 0.13 and 0.94 ± 1.87 items/m3, respectively. Totally, 15 and 16 out of 19 biocides were detected in the large plastic debris and microplastics, with the concentration of each biocide in the ranges of 22.6-2460 ng/g and 16.9-2890 ng/g, respectively. Meanwhile, the concentration ranges of the detected biocides were 0.01-215 ng/L in surface water. Triclosan, triclocarban, methylparaben, and N,N-diethyl-3-methylbenzamide (DEET) were the frequently detected compounds in the plastic samples and surface water. The partition coefficients (Kd) of biocides between the plastic debris and surface water showed a weak positive correlation with Kow values. Biocides were also detected on the natural floats (tree leaves and branches) at concentrations of 13.7-786 ng/g. The annual mass load of biocides in plastic debris at each site was up to 265 g/y, thereby suggesting that plastic debris might be an important carrier for the emerging contaminants, such as biocides.


Assuntos
Desinfetantes/análise , Monitoramento Ambiental , Plásticos/análise , Poluentes Químicos da Água/análise , Carbanilidas , China , Parabenos , Rios/química , Triclosan/análise , Resíduos/análise
17.
Sci Total Environ ; 701: 134930, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31726410

RESUMO

Natural and synthetic progestogens in livestock environments have become a concern due to the frequent presence and potential adverse effects on aquatic organisms. Here we investigated the biotransformation of progestogens by wastewater-borne bacteria in the field and laboratory under oxic and anoxic conditions. The results showed that all progestogens dissipated faster under oxic conditions than under anoxic conditions, and natural progesterone transformed faster than synthetic progestogens. Meanwhile, dozens of bacterial strains capable of degrading progestogens were successfully isolated from the swine wastewater, and Bacillus sp. P19 and Bacillus sp. DGT2 were found the best for progesterone and dydrogesterone transformation, respectively. In the degradation experiments using a single bacterial strain, progesterone and dydrogesterone dissipated under oxic conditions with half-lives of 11.6 h and 18.2 h, respectively. The transformation pathways were proposed based on the identified transformation products. The findings from this study showed that progestogens can be biotransformed, but not fully mineralized in the environment.


Assuntos
Didrogesterona/metabolismo , Progesterona/metabolismo , Águas Residuárias/microbiologia , Poluentes Químicos da Água/metabolismo , Biodegradação Ambiental , Cinética , Eliminação de Resíduos Líquidos , Águas Residuárias/química
18.
Sci Total Environ ; 683: 61-70, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31129332

RESUMO

Domestic wastewaters are an important source of endocrine disrupting chemicals in the receiving aquatic environment. Most rural domestic wastewaters (RDWs) in China have been directly discharged into the aquatic environment without any treatment. Here we studied the effects of RDWs on the western mosquitofish (Gambusia affinis) from two rural rivers receiving untreated RDWs. Mosquitofish samples were collected at 5 sampling sites along two rivers during dry and wet seasons. Sex ratios, secondary sex characteristics and transcriptional levels of target genes related to the endocrine system in adult females and males were determined. In parallel, various pollutants including steroid hormones, phenolic compounds, pesticides, polycyclic aromatic hydrocarbons (PAHs) and heavy metals were measured in the water samples at all sites. The results showed that the androgenic effects in the fish were evidenced by significant increase in male to female ratio in fish populations at two sampling sites and by the presence of modified hemal spines in females at four sampling sites when compared to the reference site. The males from the two rivers had increased Vtg mRNA expressions with a maximal 6.2-fold increase relative to the reference site and a delayed development of hemal spines. The redundancy analysis (RDA) showed that some physiological parameters were related to steroid hormones, phenolic compounds and PAHs. The findings from this study suggest that RDWs can lead to masculinization in females and feminization in males.


Assuntos
Ciprinodontiformes/metabolismo , Disruptores Endócrinos/efeitos adversos , Poluentes Químicos da Água/efeitos adversos , Animais , China , Ciprinodontiformes/genética , Disruptores Endócrinos/análise , Feminino , Proteínas de Peixes , Masculino , Rios/química , Esgotos/análise , Águas Residuárias/análise , Poluentes Químicos da Água/análise
19.
Environ Pollut ; 249: 894-903, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30965541

RESUMO

Hybrid design and artificial aeration has been widely applied in wetlands, but little is known about their effectiveness in the removal of antibiotics and antibiotic resistance genes (ARGs). Here we investigated the performance of various mesocosm-scale constructed wetlands (CWs) with artificial aeration and hybrid design in removal of antibiotics and ARGs from antibiotics-spiked domestic sewage. Four hybrid constructed wetland systems with zeolite as substrate and Iris tectorum Maxim as plant were set up to have different artificial aeration designs. The aqueous removal efficiencies of total antibiotics ranged from 87.4% to 95.3%, while those of total ARGs varied from 87.8% to 99.1%. The mass removal of antibiotics by the CWs was attributed mainly to the microbial degradation. The present study imply that sorption of substrates and biological processes could be the two main mechanisms for ARGs elimination. The results from this study showed the hybrid CWs with artificial aeration could enhance treatment efficiencies of antibiotics and ARGs as well as conventional pollutants.


Assuntos
Antibacterianos/análise , Resistência Microbiana a Medicamentos/genética , Esgotos/microbiologia , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Áreas Alagadas , Adsorção , Aerobiose , Iris (Planta)/crescimento & desenvolvimento , Esgotos/química , Zeolitas/química
20.
Ecotoxicol Environ Saf ; 172: 296-302, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30716664

RESUMO

Personal care products (PCPs) are ubiquitous in the environment due to their wide use in daily life. However, there are insufficient sediment toxicity data of PCPs under ecologically relevant conditions. Here we used Fourier transform infrared spectroscopy (FTIR) to investigate the sediment toxicity of triclosan (TCS) and galaxolide (HHCB) to two freshwater benthic macroinvertebrates, Limnodrilus hoffmeisteri and Branchiura sowerbyi, in microcosms containing a diverse biological community. Exposure to 8 µg TCS/g and 100 µg HHCB/g dry weight (dw) sediment induced significant biochemical alterations in the L. hoffmeisteri tissue. 8 µg TCS/g primarily affected proteins and nucleic acid while 100 µg HHCB/g mainly affected proteins and lipids of L. hoffmeisteri. However, 0.8 µg TCS/g and 30 µg HHCB/g did not cause significant subcellular toxicity to L. hoffmeisteri. In contrast, exposure of B. sowerbyi to 30 µg HHCB/g led to significant biochemical changes, including proteins, polysaccharides and lipids. Therefore, B. sowerbyi was more sensitive to sediment-associated HHCB than L. hoffmeisteri. Such effects were significantly enhanced when the HHCB concentration increased to 100 µg/g dw where death of B. sowerbyi occurred. These results demonstrate the application of FTIR spectroscopy to sediment toxicity testing of chemicals to benthic invertebrates with biochemical alterations as endpoints that are more sensitive than standard toxic endpoints (e.g., survival and growth).


Assuntos
Anti-Infecciosos Locais/toxicidade , Benzopiranos/toxicidade , Cosméticos/toxicidade , Oligoquetos/efeitos dos fármacos , Triclosan/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Água Doce , Sedimentos Geológicos , Espectroscopia de Infravermelho com Transformada de Fourier
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