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Groundwater contamination risk assessment using intrinsic vulnerability, pollution loading and groundwater value: a case study in Yinchuan plain, China
2020
Li, Xinyan | Wu, Hao | Qian, Hui
Groundwater contamination risk assessment is a useful tool for groundwater pollution prevention and control. Previous study has evaluated groundwater contamination risk at Yinchuan Plain, China, according to aquifer vulnerability. The present study enriches the assessment of contamination risk by adding pollution loading, which represents the hazard from human activities, and groundwater value, which represents the economic loss as a result of groundwater pollution. An approach that combines toxicity, release possibility, and the potential release quantity of pollutants on the ground surface was used to estimate the pollution loading. An integrated approach that considered both the in situ and extractive values was used to estimate groundwater value. In addition, a basic risk map was constructed by overlying the vulnerability and pollution loading maps showing the potential probability of pollution, while a value-weighted risk map was produced by overlying the basic risk and value map indicating the urgency of protection. The validation by specific contaminants shows the reliability of the basic risk assessment. Both the basic and value-weighted risk maps indicate a very high groundwater contamination risk in Yinchuan City, and the southern part of Yinchuan Plain exhibited a relatively high contamination risk. As a result of not only high vulnerability but also very high pollution loading and groundwater value, Yinchuan City is the most urgent area requiring groundwater protection. The produced maps provide effective information for decision-making regarding the optimization of monitoring network, preferential treatment, and allocating future potentially hazardous.
显示更多 [+] 显示较少 [-]Ginseng attenuates fipronil-induced hepatorenal toxicity via its antioxidant, anti-apoptotic, and anti-inflammatory activities in rats
2020
Abd Eldaim, Mabrouk Attia Abd | Abd El Latif, Amira Shehata | Hassan, Azza | El-Borai, Nermeen Borai
Fipronil (FPN) is a relatively new and broad spectrum insecticide that induces toxic effects to animals and humans through induction of oxidative stress. Ginseng is a medicinal plant that has antioxidant, anti-inflammatory, and anti-apoptotic activities. Thus, the current study was conducted to evaluate the anti-toxic potential of ginseng aqueous extract (GAE) against FPN-induced hepatorenal toxicity in rats. Thirty-two male Wistar albino rats were randomly allocated into four equal groups. Rats of the control group received distilled water. The second group was administrated with GAE at a dose of 200 mg/kg b.w. orally day by day for 6 weeks. The third group was intoxicated with FPN at a dose of 4.85 mg/kg b.w. orally day by day for 6 weeks. The fourth group was administrated with GAE 2 h before FPN intoxication. Intoxication of rats with FPN significantly elevated the activities of serum alanine aminotransferase and aspartate aminotransferase and serum levels of urea and creatinine, as well as increased malondialdehyde level and protein expressions of caspase-3 and cyclooxygenase-2 in hepatic and renal tissues. However, it significantly decreased hepatic and renal GSH content and catalase activity. In addition, it induced histopathological alterations in hepatic and renal tissue architectures. Conversely, concomitant oral administration of GAE ameliorated the FPN-induced biochemical, pathological, and histochemical alterations in both hepatic and renal tissues. This study indicated that ginseng attenuates FPN-induced hepatorenal toxicity, possibly via its antioxidant, anti-apoptotic, and anti-inflammatory properties. Graphical Abstract CAL ABSTRACTPHIRAG
显示更多 [+] 显示较少 [-]Dietary intake and health risk assessment of nitrate, nitrite, and nitrosamines: a Bayesian analysis and Monte Carlo simulation
2020
Moazeni, Malihe | Heidari, Zahra | Golipour, Sahar | Ghaisari, Leila | Sillanpää, Mika | Ebrahimi, Afshin
Nitrate, nitrite, and nitrosamines intake from the diet creates human health risks. In this study, nitrate/nitrite intake from diet and its association with nitric oxide (NO) level in humans have been surveyed. Besides nitrate/nitrite, nitrosamines risks were also determined from the diet. This study was conducted as a pilot study; 33 heathy adults participated in and completed the Food Frequency Questionnaire (FFQ) for 3 days. Then, concentrations of nitrate, nitrite, and nitrosamines were studied by the literature review. Also, the association between the intake of nitrate and nitrite with salivary and urinary NO was evaluated by Bayesian bi-variate analysis. Then, the health risk was assessed for nitrate/nitrite from food groups and drinking water, and nitrosamines from food groups based on hazard index (HI) and cancer risk with the Monte Carlo simulation. The nitrate/nitrite intakes had no association with NO level in the saliva and urine samples. The mean of HI value for the mean of 3 days was 3.57 and 0.32 from food groups and drinking water, respectively. The cancer risk amount of nitrosamines from food groups was (1.74 to 2.22) × 10⁻³ based on 95% confidence interval (CI 95%) values. This study showed the Iranian diet had a high risk, but drinking water consumption was safe based on nitrate/nitrite and nitrosamines for humans. There is a need to determine the concentration of nitrosamines in drinking water in Iran and to recommend for decrease risk of nitrate, nitrite, and nitrosamines exposure by food groups.
显示更多 [+] 显示较少 [-]Determinants of economic growth and environmental sustainability in South Asian Association for Regional Cooperation: evidence from panel ARDL
2020
Khan, Syed Abdul Rehman | Yu, Zhang | Sharif, Arshian | Golpîra, Hêriş
Considering the importance of green economic growth and environmental sustainability in the discussion, it is crucial to understand its critical contributing factors and to draw results implications for the green policy. This research used the data of the South Asian Association for Regional Cooperation (SAARC) member countries for a period from 2005 to 2017. It adopted the panel autoregressive distributed lag technique to examine the hypotheses. The findings revealed that environmental sustainability is strongly and positively associated with national scale-level green practices, including renewable energy, regulatory pressure, and eco-friendly policies, and sustainable use of natural resources. Conversely, in our model, the “regulatory pressure” has an insignificant effect on economic growth. A necessary contribution of the present study is that a positive effect of green practices on national scale economic and environmental variables, particularly in the scenario of SAARC member states, can be noticed. At the end of the present study, we have provided policy implications for regulatory authorities and discussed potential areas for future research.
显示更多 [+] 显示较少 [-]Microplastics in a dam lake in Turkey: type, mesh size effect, and bacterial biofilm communities
2020
Tavşanoğlu, Ülkü Nihan | Başaran Kankılıç, Gökben | Akca, Gülçin | Çırak, Tamer | Erdoğan, Şeyda
The evaluation of microplastic (MP) pollution has been drawing attention for the last decades. MP pollution has been studied widely in marine environments, but limited data exists for freshwater ecosystems on potential source and transport of MPs. The type, shape, plastic components, and the color of the MPs were investigated using various-mesh-sizes (300 and 100 μm) nets in four sampling stations of Süreyyabey Dam Lake in Turkey. The growth of bacterial isolates on the MPs surface and surrounding water was also investigated. The type of the MPs and the interaction between the mesh size and the type of the MPs showed significant differences (p < 0.05). Fibers were found to be the most abundant particle type constituting 45% and 80% of the total MPs found in 330-μm and 100-μm mesh sizes, respectively. In total the observed MP abundance in the dam lake was 5.25 particles m⁻³, and 4.09 particles m⁻³ was observed for 100-μm and 330-μm mesh sizes, respectively. The color of the identified microplastics showed variations among microplastic types; however, the dominant color was transparent in each net. The main plastic components of the MPs are polyethylene terephthalate, polyvinyl chloride, polystyrene, polyethylene, and polypropylene. The microbial community mainly consists of potentially pathogenic strains such as Escherichia coli, Enterococcus faecalis, and Acinetobacter baumanii complex. The current study could contribute valuable background information both for MP pollution and for biofilm composition in a dam. However, the surface of the MPs and biofilm formation should be investigated urgently to understand the vector potential of MPs.
显示更多 [+] 显示较少 [-]Impact of Land Cover Changes on the Soil and Water Quality of Greens Bayou Watershed
2020
Sridhar, Balaji Bhaskar Maruthi | Johnson, Jericho | Mosuro, Adeola
Rapid land use and land cover changes have a significant effect on ecology, environment, and human health in urban watersheds. With increase in frequency and intensity of the urban flooding events and repeated inundation of the neighborhoods, it is important to monitor the water and soil chemical characteristics in Greens Bayou Watershed (GBW) region. The objectives of this study were to (1) analyze the nutrient and heavy metal concentrations in water and soil samples along the Greens Bayou, (2) monitor the historical water quality data, and (3) identify and analyze land cover changes in the watershed using Landsat imagery. A total of 12 water and 12 soil samples, from four different sampling locations along the Greens Bayou, were collected during two seasons and processed for chemical analysis. Our water sample analysis revealed that the As, Cd, Pb, and Hg concentrations were higher in the fall compared with the summer and exceeded the critical limit. The soil analysis indicated that the Zn and Pb concentrations were higher in the fall over summer season and exceeded the background concentrations. Remote sensing analysis revealed that the impervious surface in the GBW increased by about 62.2% while the vegetative surface decreased by 30.6% during the period of 1984 to 2018. Environmental chemical analysis coupled with geospatial data demonstrated the impact of land cover changes on water and soil quality along the Greens Bayou by identifying areas vulnerable to change, which can be better managed to preserve the health of this urban watershed ecosystem.
显示更多 [+] 显示较少 [-]Dietary intake assessment of pyrethroid residues from okra and eggplant grown in peri-urban areas of Punjab, Pakistan
2020
Amjad, Adnan | Randhawa, Muhammad Atif | Javed, Muhammad Sameem | Muhammad, Zafarullah | Ashraf, Mussawar | Ahmad, Zulfiqar | Murtaza, Shamas
This study was designed to assess the gradual increase in the use of insecticides on vegetables and to familiarize the consumers regarding the insecticide residues. The purpose of this research work was to highlight the detrimental effects of pyrethroids (bifenthrin, cyfluthrin, cypermethrin, deltamethrin, fenvalerate, lambda-cyhalothrin, and permethrin) compare with dietary intake assessment of eggplant and okra grown in peri-urban environment. In this manner, a total of 180 (n = 60 × 3) samples of eggplant (Solanum melongena) and okra (Abelmoschus esculentus) were procured from the peri-urban farming system of Faisalabad, Multan, and Gujranwala to assess the pyrethroid residues along with their dietary intake assessment. The procured vegetables were quantified for pyrethroid residues by using gas chromatography (GC) equipped with an electron capture detector (ECD). Outcomes of this study revealed that for okra samples, the highest residues of bifenthrin (1.25 mg kg⁻¹) were found in Gujranwala then Multan (1.5 mg kg⁻¹) and Faisalabad (1.04 mg kg⁻¹), whereas in eggplant, the highest residues were recorded for bifenthrin from Faisalabad (1.33 mg kg⁻¹) and Gujranwala (0.78 mg kg⁻¹). In Multan, the highest residues for cyfluthrin (1.18 mg kg⁻¹) were reported in eggplant. Out of all analyzed samples for pyrethroid residues, 32% samples contained detectable residues and 6% samples exceeded their maximum residual limits (MRLs) established by the European Union (EU). Dietary intake assessment (mg kg⁻¹ day⁻¹) was calculated as per their maximum permissible intake (MPI) values, i.e., bifenthrin (1.28), cyfluthrin (1.28), cypermethrin (3.20), deltamethrin (0.64), fenvalerate (1.28), lambda-cyhalothrin (0.064), and permethrin (3.20) respectively. Conclusively, residues from the Multan region were greater than those from Gujranwala and Faisalabad showing excessive application of pyrethroids. Overall results revealed that although some samples exceeded MRLs in selected areas, their safe consumption limit was found.
显示更多 [+] 显示较少 [-]Beta radioactivity of urban surface–deposited sediment in three Russian cities
2020
Hanfi, Mohamed Y. | Yarmoshenko, Ilia V. | Seleznev, Andrian A. | Malinovsky, Georgy | Ilgasheva, Ekaterina | Zhukovsky, Michael V.
Study of gross beta activity was conducted in Russian cities Ekaterinburg, Rostov-on-Don, and Nizhny Novgorod. The cities were characterized by continental climate, although they are located in different geographical zones. The bulk urban samples were fractionated with three size fractions: dust (0.002–0.1 mm), fine sand (0.1–1 mm), and coarse sand (> 1 mm). Measurement setup equipped with beta radiometer BDPB-01 was designed to measure the low levels of gross beta-activity in a small amount of the obtained size-fractionated samples. According to the results of the study, the gross beta activity depends on the size fraction and the city. The highest beta activity concentration was found in the dust fraction which is about the same in all cities 0.8–0.9 Bq g⁻¹. In size fractions of fine sand and coarse sand, the beta activity depends on the city. Among other cities, the highest average beta concentration was found in Ekaterinburg (0.8 and 0.6 Bq g⁻¹ in fine and coarse sand fractions, respectively), while the lowest is 0.28 and 0.44 Bq g⁻¹, respectively. The relationship of beta activity concentration with mineral and chemical composition is studied. Average beta activity in the different fractions of the surface–deposited sediment correlates with uranium, thorium, and organic matter concentration. The gross beta activity may be considered an indicator of high contribution of dust and high pollution with Pb, Cu, and Zn in the urban environment.
显示更多 [+] 显示较少 [-]Extremely low-frequency electromagnetic field induces a change in proliferative capacity and redox homeostasis of human lung fibroblast cell line MRC-5
2020
Lekovic, Maida H. | Drekovic, Nerkesa E. | Granica, Nihat Dz | Mahmutovic, Elvis H. | Djordjevic, Natasa Z.
Numerous studies have shown that extremely low-frequency electromagnetic field (ELF-EMF) by modulating oxidative-antioxidative balance in the cells achieved beneficial and harmful effects on living organisms. The aim of this study was to research changes of both proliferative capacity and redox homeostasis of human lung fibroblast cell line MRC-5 during exposure to ELF-EMF (50 Hz). The human lung fibroblast cell line MRC-5 were exposed to ELF-EMF once a day in duration of 1 h during 24 h (1 treatment 1 h/day), 48 h (2 treatments 1 h/day), 72 h (3 treatments 1 h/day), and 7 days (7 treatments 1 h/day). After 24 h of the last treatment, the proliferative capacity of the cells and the concentrations and activities of the components of the oxidative/antioxidative system were determined: superoxide anion (O₂.⁻), hydrogen peroxide (H₂O₂), nitric oxide (NO), peroxynitrite (ONOO⁻), reduced glutathione (GSH), oxidized glutathione (GSSG), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione reductase (GR), and glutathione-S-transferase (GST). The results of this study show that ELF-EMF may affect a cell cycle regulation of human lung fibroblast cell line MRC-5 through modulation of oxidative/antioxidative defense system. The effects of ELF-EMF on proliferation and redox balance of human lung fibroblast cell line MRC-5 depend on exposure time.
显示更多 [+] 显示较少 [-]Diurnal and seasonal variations of odor emissions from broiler and cage-layer barns in the Canadian Prairies
2020
Huang, Dandan | Guo, Huiqing
Odor concentrations (OC) and emissions (OE) were measured for a commercial broiler barn and a cage-layer barn in a cold region (the Canadian Prairies). Seasonal OC and OE profiles were plotted by monthly measurements over the course of a year from March 2015 to February 2016, and diurnal profiles were generated by 2-day measurements in cold, mild, and warm seasons, respectively. Seasonal OC and OE varied for both barns; OC was higher in the cold season, but OE was higher in the mild and warm seasons. The broiler barn had higher annual average OC (718 OU m⁻³) but slightly lower annual average OE (127 OU s⁻¹ AU⁻¹; AU is per 500 kg of body mass) than the layer barn (574 OU m⁻³ and 140 OU s⁻¹ AU⁻¹). For the layer barn, OC and OE were reduced by 31% and 33% in the cold season and by 30% and 26% in the mild season after manure removal compared with before manure removal. Statistical results showed increased outdoor temperature and ventilation rate (VR) were associated with decreased OC but increased OE for both barns. Finally, both single linear and multi-linear regression models of OE were developed.
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