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Anti-inflammatory drugs in the marine environment: Bioconcentration, metabolism and sub-lethal effects in marine bivalves Texto completo
2020
Almeida, Angela Maria da | Solé, Montserrat | Soares, Amadeu M.V.M. | Freitas, Rosa
Anti-inflammatory drugs in the marine environment: Bioconcentration, metabolism and sub-lethal effects in marine bivalves Texto completo
2020
Almeida, Angela Maria da | Solé, Montserrat | Soares, Amadeu M.V.M. | Freitas, Rosa
Pharmaceuticals such as non-steroidal anti-inflammatory drugs (NSAIDs) have been found in the marine environment. Although there is a large body of evidence that pharmaceutical drugs exert negative impacts on aquatic organisms, especially in the freshwater compartment, only limited studies are available on bioconcentration and the effects of NSAIDs on marine organisms. Bivalves have a high ecological and socio-economic value and are considered good bioindicator species in ecotoxicology and risk assessment programs. Therefore, this review summarizes current knowledge on the bioconcentration and the effects of three widely used NSAIDs, diclofenac, ibuprofen and paracetamol, in marine bivalves exposed under laboratory conditions. These pharmaceutical drugs were chosen based on their environmental occurrence both in frequency and concentration that may warrant their inclusion in the European Union Watch List. It has been highlighted that ambient concentrations may result in negative effects on wild bivalves after long-term exposures. Also, higher trophic level organisms may be more impacted due to food-chain transfer (e.g., humans are shellfish consumers). Overall, the three selected NSAIDs were reported to bioconcentrate in marine bivalves, with recognized effects at different life-stages. Immune responses were the main target of a long-term exposure to the drugs. The studies selected support the inclusion of diclofenac on the European Union Watch List and highlight the importance of extending research for ibuprofen and paracetamol due to their demonstrated negative effects on marine bivalves exposed to environmental realistic concentrations, under laboratory conditions.
Mostrar más [+] Menos [-]Anti-inflammatory drugs in the marine environment: Bioconcentration, metabolism and sub-lethal effects in marine bivalves Texto completo
2020
Almeida, Ângela | Solé, Montserrat | Soares, Amadeu M. V. M. | Freitas, Rosa | Agencia Estatal de Investigación (España) | Fundação para a Ciência e a Tecnologia (Portugal) | European Commission
11 pages, 1 figure, 2 tables | Pharmaceuticals such as non-steroidal anti-inflammatory drugs (NSAIDs) have been found in the marine environment. Although there is a large body of evidence that pharmaceutical drugs exert negative impacts on aquatic organisms, especially in the freshwater compartment, only limited studies are available on bioconcentration and the effects of NSAIDs on marine organisms. Bivalves have a high ecological and socio-economic value and are considered good bioindicator species in ecotoxicology and risk assessment programs. Therefore, this review summarizes current knowledge on the bioconcentration and the effects of three widely used NSAIDs, diclofenac, ibuprofen and paracetamol, in marine bivalves exposed under laboratory conditions. These pharmaceutical drugs were chosen based on their environmental occurrence both in frequency and concentration that may warrant their inclusion in the European Union Watch List. It has been highlighted that ambient concentrations may result in negative effects on wild bivalves after long-term exposures. Also, higher trophic level organisms may be more impacted due to food-chain transfer (e.g., humans are shellfish consumers). Overall, the three selected NSAIDs were reported to bioconcentrate in marine bivalves, with recognized effects at different life-stages. Immune responses were the main target of a long-term exposure to the drugs. The studies selected support the inclusion of diclofenac on the European Union Watch List and highlight the importance of extending research for ibuprofen and paracetamol due to their demonstrated negative effects on marine bivalves exposed to environmental realistic concentrations, under laboratory conditions | Ângela Almeida benefited from PhD grant (SFRH/BD/110218/2015) given by the National Funds through the Portuguese Science Foundation (FCT), supported by FSE and Programa Operacional Capital Humano (POCH) e European Union. Rosa Freitas was funded by national funds (OE), through FCT – Fundação para a Ciência e a Tecnologia, I.P., in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19. This work was also financially supported by the project BISPECIAl: BIvalveS under Polluted Environment and ClImate chAnge PTDC/CTA-AMB/28425/2017 (POCI-01-0145-FEDER-028425) funded by FEDER, through COMPETE2020 - Programa Operacional Competitividade e Internacionalização (POCI), and by national funds (OE), through FCT/MCTES. Thanks are due for the financial support to CESAM (UIDB/50017/2020+UIDP/50017/2020), to FCT/MEC through national funds, and the co-funding by the FEDER, within the PT2020 Partnership Agreement and Compete 2020. The authors also acknowledge to the RED RIESCOS - Evaluación de los Efectos de los Contaminantes Emergentes en Organismos Acuáticos y sobre la Salud Humana, from the Programa Iberoamericano de Ciencia y Tecnología para el Desarrollo (CYTED) with the reference 419RT0578 | With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI)
Mostrar más [+] Menos [-]RETRACTED: Microplastic pollution in intertidal sediments along the coastline of China Texto completo
2020
Wang, Qing | Shan, Encui | Zhang, Bin | Teng, Jia | Wu, Di | Yang, Xin | Zhang, Chen | Zhang, Wenjing | Sun, Xiyan | Zhao, Jianmin
This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal).This article has been retracted at the request of the Editors-in-Chief and Authors. The corresponding author informed the journal that full permission had not been obtained to use all the samples documented in the study. The authors apologise for any inconvenience caused.
Mostrar más [+] Menos [-]Occurrence of caffeine in the freshwater environment: Implications for ecopharmacovigilance Texto completo
2020
Li, Shulan | Wen, Jing | He, Bingshu | Wang, Jun | Hu, Xianmin | Liu, Juan
Owing to the substantial consumption of caffeinated food, beverages, and medicines worldwide, caffeine is considered the most representative pharmaceutically active compound (PhAC) pollutant based on its high abundance in the environment and its suitability as an indicator of the anthropogenic inputs of PhACs in water bodies. This review presents a worldwide analysis of 132 reports of caffeine residues in freshwater environments. The results indicated that more than 70% of the studies reported were from Asia and Europe, which have densely populated and industrially developed areas. However, caffeine pollution was also found to affect areas isolated from human influence, such as Antarctica. In addition, the maximum concentrations of caffeine in raw wastewater, treated wastewater, river, drinking water, groundwater, lake, catchment, reservoir, and rainwater samples were reported to be 3.60 mg/L, 55.5, 19.3, 3.39, 0.683, 174, 44.6, 4.87, and 5.40 μg/L, respectively. The seasonal variation in caffeine residues in the freshwater environment has been demonstrated. In addition, despite the fact that there was a small proportion of wastewater treatment plants in which the elimination rates of caffeine were below 60%, wastewater treatment is generally believed to have a high caffeine removal efficiency. From a pharmacy perspective, we proposed to adopt effective measures to minimize the environmental risks posed by PhACs, represented by caffeine, through a new concept known as ecopharmacovigilance (EPV). Some measures of EPV aimed at caffeine pollution have been advised, as follows: improving knowledge and perceptions about caffeine pollution among the public; listing caffeine as a high-priority PhAC pollutant, which should be targeted in EPV practices; promoting green design and production, rational consumption, and environmentally preferred disposal of caffeinated medicines, foods, and beverages; implementing intensive EPV measures in high-risk areas and during high-risk seasons; and integrating EPV into wastewater treatment programs.
Mostrar más [+] Menos [-]Changes in ozone photochemical regime in Fresno, California from 1994 to 2018 deduced from changes in the weekend effect Texto completo
2020
de Foy, Benjamin | Brune, William H. | Schauer, James J.
Significant progress has been made in reducing emissions of air pollutants in the San Joaquin Valley in California. Nevertheless, from May to October, the valley still experiences numerous exceedances of the ozone health standard. As the standards are tightened, it is becoming harder to design policies to attain them. To better understand historical emissions reductions in the context of necessary future control efforts, we analyze 25 years of hourly measurements of ozone and nitrogen oxides concentrations for the hottest one third of days in Fresno using multiple linear regression analysis. We then analyze the changing dynamics of the weekend effect over the years in order to evaluate the growing importance of day-to-day carryover on ozone concentrations. A simplified model of the day-of-week pattern of ozone concentrations is used to explore the impact of same-day and previous-day concentrations. In addition to ozone, Oₓ (O₃ + NO₂) is used to distinguish reductions of atmospheric oxidants from short-duration exchanges between O₃ and NO₂. The analysis shows that there has been a significant increase in the importance of day-to-day carryover on ozone levels, and that consequently the ozone weekend effect in Fresno has changed over the last 25 years. In the 1990s, lower NOₓ on the weekend led to increased ozone on Saturdays and Sundays but levels of Oₓ remained constant. In the 2010s, lower weekend NOₓ led to reduced ozone on Saturdays, Sundays and Mondays showing that reductions in primary pollutants are sufficient to yield immediate decreases in secondary pollutants. Overall, the photochemical regime in the atmosphere has evolved such that carryover and regional pollution will be increasingly important in determining local ozone concentrations. Policies will therefore need to pay greater attention to regional emissions as local reductions may not be sufficient to meet the health standard.
Mostrar más [+] Menos [-]Effect of spraying on coal dust diffusion in a coal mine based on a numerical simulation Texto completo
2020
Ma, Qingxin | Nie, Wen | Yang, Shibo | Xu, Changwei | Peng, Huitian | Liu, Zhiqiang | Guo, Cheng | Cai, Xiaojiao
Aimed at effectively controlling coal dust pollution in the mining face of a coal mine, this study first conducted a theoretical analysis and then combined a spraying experiment and a numerical simulation to perform an in-depth examination of the atomizing characteristics and dust suppression performance of a coal cutter external spraying device. Based on the experimental spraying results, the optimal nozzle was determined to be a pressure round-mouth nozzle with an X-shaped core. The characteristics of the spray fields from nozzles of different calibers (1.6, 2.0 and 2.4 mm) at different spraying pressures (2, 4, 6 and 8 MPa) were then analyzed. It was found that the droplet concentration in the spray field increased with increasing spraying pressure and nozzle caliber. The droplet diameter was mainly dependent on the spraying pressure and varied more slowly with increased spraying pressure. At a spraying pressure of 8 MPa, the spray field formed could achieve effective dust suppression; specifically, the droplet concentration in the spray field was mostly more than 15 g/m³, and the droplet size was mainly distributed in the range of 30–100 μm. When using a 2.4 mm caliber nozzle, the dust concentration measured around the coal cutter operator was reduced to 87.21 mg/m³ under a spraying pressure of 8 MPa, suggesting adequate dust suppression.
Mostrar más [+] Menos [-]Effects of NOx and SO2 on the secondary organic aerosol formation from the photooxidation of 1,3,5-trimethylbenzene: A new source of organosulfates Texto completo
2020
Yang, Zhaomin | Tsona, Narcisse T. | Li, Jianlong | Wang, Shuyan | Xu, Li | You, Bo | Du, Lin
1,3,5-Trimethylbeneze (TMB) is an important constituent of anthropogenic volatile organic compounds that contributes to the formation of secondary organic aerosol (SOA). A series of chamber experiments were performed to probe the effects of NOₓ and SO₂ on SOA formation from TMB photooxidation. The molecular composition of TMB SOA was investigated by ultra-high performance liquid chromatography/electrospray ionization high-resolution quadrupole time-of-flight mass spectrometry (UPLC/ESI-HR-Q-TOFMS). We found that the SOA yield increases notably with elevated NOₓ concentrations under low-NOₓ condition ([TMB]₀/[NOₓ]₀ > 10 ppbC ppb⁻¹), while an opposite trend is observed in high-NOₓ experiments ([TMB]₀/[NOₓ]₀ < 10 ppbC ppb⁻¹). The increase in SOA yield in low-NOₓ regime is attributed to the increase of NOₓ-induced OH concentrations. The formation of low-volatility species might be suppressed, thereby leading to a lower SOA yield in high-NOₓ conditions. Moreover, SOA formation was promoted in experiment with SO₂ addition. Multifunctional products containing carbonyl, acid, alcohol, and nitrate functional groups were characterized in TMB/NOₓ photooxidation, whereas several organosulfates (OSs) and nitrooxy organosulfates were identified in TMB/NOₓ/SO₂ photooxidation based on HR-Q-TOFMS analysis. The formation mechanism relevant to the detected compounds in SOA were proposed. Based on our measurements, the photooxidation of TMB in the presence of SO₂ may be a new source of OSs in the atmosphere. The results presented here also deepen the understanding of SOA formation under relatively complex polluted environments.
Mostrar más [+] Menos [-]Cadmium source identification in soils and high-risk regions predicted by geographical detector method Texto completo
2020
Zhao, Yinjun | Deng, Qiyu | Lin, Qing | Zeng, Changyu | Zhong, Cong
Cadmium (Cd) contamination in soils has become a serious and widespread environmental problem, especially in areas with high natural background Cd values, but the mechanism of Cd enrichment in these areas is still unclear. This study uses the Guangxi Zhuang Autonomous Region (Guangxi), a typical area with a high background Cd level and Cd pollution related to mining activities, as an example to explore the source and predict areas with high Cd risk in soils based on the geographical detector method. The areas with high Cd in Guangxi soils were classified into non-mining areas and mining areas according to their potential Cd sources. The results show that the rich Cd content in the soils from the non-mining area of Guangxi was mainly derived from the soil type (q = 0.34), geological age (q = 0.27), rock type (q = 0.26) and geomorphic type (q = 0.20). Specifically, the Cd content was derived from the weathering and deposition processes of carbonatite from the Carboniferous system in the karst area. The high Cd content in the soils of the mining area of Guangxi was mainly derived from the area mined for mineral resources (q = 0.08) and rock type (q = 0.05). Specifically, the Cd content was derived from the mining of lead-zinc ores. The areas in Guangxi with a high risk of Cd soil pollution are mostly concentrated in karst areas, such as Hechi, Laibin, Chongzuo, southern Liuzhou and Baise, northern Nanning city and northeastern Guilin city, and some mining areas. These results indicated that the high Cd concentration in the soils of large areas of Guangxi is probably due to natural sources, while the high Cd concentration around mining areas is due to anthropogenic sources. The results will be useful for soil restoration and locating and controlling contaminated agricultural land.
Mostrar más [+] Menos [-]Strong influence of surfactants on virgin hydrophobic microplastics adsorbing ionic organic pollutants Texto completo
2020
Xia, Yan | Zhou, Juan-Juan | Gong, Yan-Yan | Li, Zhan-Jun | Zeng, E. Y. (Eddy Y.)
Microplastic (MP) pollution has become an area of increasing concern because MPs accumulate various types of pollutants. Many previous studies have explored the interactions between MPs and hydrophobic pollutants. However, little research has been conducted on hydrophilic pollutants, which are of much higher concentration and ubiquitous in environment. Surfactants cause hydrophobic MPs to become hydrophilic, which may significantly enhance their capacities to adsorb hydrophilic pollutants. This study explored the influence of co-existing surfactants on the adsorption of ionic organic pollutants by MPs, and found that the presence of an ionic surfactant could significantly enhance the capacity of polyvinyl chloride (PVC, 0.2 mm) MPs to adsorb pollutants with opposite charges. The Langmuir methylene blue adsorption capacity of PVC could be increased from 172 to 4417 ppm in the presence of a sodium dodecyl benzene sulfonate surfactant. Nonionic surfactants impeded the adsorption of both cationic and anionic pollutants due to the steric resistance of the hydrophilic polyethelene glycol chains. The electrostatic interaction mechanism dominated the interfacial behaviors of ionic pollutants on surfactant-adsorbed MP interfaces. The effects of the surfactants were further verified using four different model pollutants and six surfactants. The adsorption capacities of real environmental MPs, including PVC, polyethylene (PE), polypropylene (PP), and polystyrene (PS), increased by three to twenty-six times. The adsorption properties of MPs may be determined by the presence of co-existing surfactants, rather than their polymer species or additives.
Mostrar más [+] Menos [-]Immunotoxicity and neurotoxicity of bisphenol A and microplastics alone or in combination to a bivalve species, Tegillarca granosa Texto completo
2020
Tang, Yu | Zhou, Weishang | Sun, Shuge | Du, Xueying | Han, Yu | Shi, Wei | Liu, Guangxu
Though invertebrates are one of the largest groups of animal species in the sea and exhibit robust immune and neural responses that are crucial for their health and survival, the potential immunotoxicity and neurotoxicity of the most produced chemical bisphenol A (BPA), especially in conjunction with microplastics (MPs), still remain poorly understood in marine invertebrate species. Therefore, the impacts of exposure to BPA and MPs alone or in combination on a series of immune and neural biomarkers were investigated in the invertebrate bivalve species blood clam (Tegillarca granosa). Evident immunotoxicity as indicated by alterations in hematic indexes was observed after two weeks of exposure to BPA and MPs at environmentally realistic concentrations. The expression of four immune-related genes from the NFκB signaling pathway was also found to be significantly suppressed by the BPA and MP treatment. In addition, exposure to BPA and MPs led to an increase in the in vivo contents of three key neurotransmitters (GABA, DA, and ACh) but a decrease in the expression of genes encoding modulatory enzymes and receptors for these neurotransmitters, implying the evident neurotoxicity of BPA and MPs to blood clam. Furthermore, the results demonstrated that the toxic impacts exerted by BPA were significantly aggravated by the co-presence of MPs, which may be due to interactions between BPA and MPs as well as those between MPs and clam individuals.
Mostrar más [+] Menos [-]A field study on the effects of combined biomanipulation on the water quality of a eutrophic lake Texto completo
2020
Chen, Zhaoqiong | Zhao, Dan | Li, Mingliang | Tu, Weiguo | Luo, Xiaoming | Liu, Xin
Lake eutrophication has become a serious environmental problem in China. Manipulations covering more elements of trophic pyramid are methods for lakes to obtain clear water state and should be studied in detail. In the present study, Meishan Dongpo Lake was divided into two parts, and a combined biomanipulation project was conducted in one part (RLake), and the other part was used as a control (CLake). Species of submerged-plant, fish, macrobenthos, and zooplankton were screened and a certain number of them were added to adjust the eco-chain in RLake. After restoration, the coverage of submerged macrophytes reached >85%; zooplankton greater than 0.6 mm in size increased in number, and the ratio of zooplankton biomass to chlorophyll-a (Chl-a) concentration increased. The dominant fish species changed, and disturbance of the sediment was reduced. The average density of mollusks in RLake was 111.5 ± 19.8 ind m⁻², which was much higher than that in CLake (36.7 ± 2.1 ind m⁻²). Water quality and clarity were substantially improved, and nutrient concentrations, particularly total phosphorus, total nitrogen, and Chl-a were significantly reduced. The aquatic community parameters were negatively correlated with the nutrient parameters and Chl-a. The ecological restoration have adjusted the aquatic ecosystem in RLake, and many positive feedback effects among the aquatic communities made them remove internal nutrients and Chl-a more efficiently.
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