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Toxicity and Enterobacteriaceae Profile in Water in Different Hydrological Events: a Case from South Brazil 全文
2021
Fonseca, Tauani G. | Motta, Elaine A. | Mass, Apolline P. | Fongaro, Gislaine | Ramos, Fernando M. | Machado, Marinara S. | Bocchese, Daniel C. F. | Viancelli, Aline | Michelon, William
Climatic changes have altered the water cycle, leading to more frequent occurrences of natural disasters, such as floods. In such events, quality of life is compromised due to environmental changes and widespread of pathogens. Unfortunately, scientific knowledge on bacteria behavior during different hydrological events is still scarce, and such knowledge is essential for the decision-making process regarding flood prevention and mitigation measures. Therefore, the present study aimed to investigate the changes in the enterobacteriaceae community and toxicity from river water samples collected during hydrological cycles over the rainy and dry seasons and on flood events. Additionally, a principal component analysis was performed to verify the relation between microbial and chemical profiles and the hydrological events. Results showed the presence of 153 enterobacteriaceae from 32 different species and of toxic substances on water samples collected during all hydrological events. During the rainy period, the Escherichia coli concentration increased along the river, and during flood events, the diversity of bacteria increased. However, bacterial diversity was not statistically associated with a specific hydrological event. These events can happen all around the world, and due to climatic changes associated with overpopulated unplanned areas, new flood-prone areas can appear rapidly, favoring the occurrence of waterborne outbreaks.
显示更多 [+] 显示较少 [-]The role of disinfectants and sanitizers during COVID-19 pandemic: advantages and deleterious effects on humans and the environment 全文
2021
Dhama, Kuldeep | Patel, Shailesh Kumar | Kumar, Rakesh | Masand, Rupali | Rana, Jigyasa | Yatoo, Mohd Iqbal | Tiwari, Ruchi | Sharun, Khan | Mohapatra, Ranjan K. | Natesan, Senthilkumar | Dhawan, Manish | Ahmad, Tauseef | Emran, Talha Bin | Malik, Yashpal Singh | Harapan, Harapan
Disinfectants and sanitizers are essential preventive agents against the coronavirus disease 2019 (COVID-19) pandemic; however, the pandemic crisis was marred by undue hype, which led to the indiscriminate use of disinfectants and sanitizers. Despite demonstrating a beneficial role in the control and prevention of COVID-19, there are crucial concerns regarding the large-scale use of disinfectants and sanitizers, including the side effects on human and animal health along with harmful impacts exerted on the environment and ecological balance. This article discusses the roles of disinfectants and sanitizers in the control and prevention of the current pandemic and highlights updated disinfection techniques against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This article provides evidence of the deleterious effects of disinfectants and sanitizers exerted on humans, animals, and the environment as well as suggests mitigation strategies to reduce these effects. Additionally, potential technologies and approaches for the reduction of these effects and the development of safe, affordable, and effective disinfectants are discussed, particularly, eco-friendly technologies using nanotechnology and nanomedicine.
显示更多 [+] 显示较少 [-]A field-scale remediation of residual light non-aqueous phase liquid (LNAPL): chemical enhancers for pump and treat 全文
2021
Ciampi, Paolo | Esposito, Carlo | Cassiani, Giorgio | Deidda, Gian Piero | Rizzetto, Paolo | Papini, Marco Petrangeli
The remediation of petroleum-contaminated soil and groundwater is a challenging task. The petroleum hydrocarbons have a long persistence in both the vadose zone and in the aquifer and potentially represent secondary and residual sources of contamination. This is particularly evident in the presence of residual free-phase. Pump-and-treat is the most common hydrocarbon decontamination strategy. Besides, it acts primarily on the water dissolved phase and reduces concentrations of contaminants to an asymptotic trend. This study presents a case of enhanced light non-aqueous phase liquid (LNAPL) remediation monitored using noninvasive techniques. A pilot-scale field experiment was conducted through the injection of reagents into the subsoil to stimulate the desorption and the oxidation of residual hydrocarbons. Geophysical and groundwater monitoring during pilot testing controlled the effectiveness of the intervention, both in terms of product diffusion capacity and in terms of effective reduction of pollutant concentrations. In particular, non-invasive monitoring of the reagent migration and its capability to reach the target areas is a major add-on to the remediation technique. Most of the organic contaminants were decomposed, mobilized, and subsequently removed using physical recovery techniques. A considerable mass of contaminant was recovered resulting in the reduction of concentrations in the intervention areas.
显示更多 [+] 显示较少 [-]Cytotoxicity and mutagenicity of the waters of the Marrecas River (Paraná, Brazil) to bullfrogs (Lithobates catesbeianus) 全文
2021
dos Santos, Flavia Isabelli | Mizobata, Andressa Akemi | Suyama, Gabrielle Arisa | Cenci, Giovana Baptista | Follador, Franciele Ani Caovilla | Arruda, Gisele | Hellmann, Liliane | Gomes, Eduardo Michel Vieira | de Oliveira Schmitz, Ana Paula | Pokrywiecki, Juan Carlos | Lingnau, Rodrigo | Manosso, Fernando Cesar | Pokrywiecki, Ticiane Sauer | Düsman, Elisângela
Animals have a long history of assessing ecosystem responses to environmental disturbances, and amphibians stand out for presenting themselves as good animal model and bioindicators of environmental quality. The main purpose of the present work was to investigate the cellular effects of contamination of waters of the Marrecas River, located in the southwest of the state of Paraná, Brazil. Therefore, the objective of the present study was to investigate and monitor the cytotoxic and mutagenic effect, with bullfrog tadpoles, and to discuss these effects with land use along this hydrographic basin. Mutagenic effects were determined by micronucleus assay, and cytotoxicity by other nuclear changes, such as segmented cells, binucleated cells, cells with buds and reniform cells. Water samples were obtained at nine sites along the Marrecas River, covering areas with rural and urban hydrological contribution. For each site, four samples were collected, along the years 2017 and 2018, encompassing the four seasons (summer, autumn, winter, and spring). The results showed mutagenic and cytotoxic effect in four sampling sites, and only cytotoxic effect in other four sites. These effects may be due, possibly, to the use of different agrochemicals across the hydrographic basin region, which have predominant hydrological contributions from crops. Data of this study indicate the presence of cytotoxic and mutagenic contaminants in the waters of the Marrecas River, which can generate environmental problems on the river fauna/flora, and can also affect the local population health.
显示更多 [+] 显示较少 [-]Estimation of PM10 pollutant and its effect on total mortality (TM), hospitalizations due to cardiovascular diseases (HACD), and respiratory disease (HARD) outcome 全文
2021
Tahery, Noorollah | Geravandi, Sahar | Goudarzi, Gholamreza | Shahriyari, Habib Allah | Jalali, Saeid | Mohammadi, Mohammad Javad
Dust storms not only affect the quality of life but also pose a serious health and social problem. The main source dust events include central and west Asia, the Taklimakan desert, and Middle East, carrying out high volume of particulate matter, which increased the level of PM₁₀ as representative of dust storm. The purpose of this study was to investigate the number of mortality (TM), hospitalizations due to cardiovascular diseases (HACD) and respiratory diseases (HARD) among the people of Bishkek and Ahvaz. Data validation was performed using the WHO criteria. The average time PM₁₀ in outdoor air was calculated, and its health effects were obtained by entering its annual data and population at risk, baseline incidence (BI), and relative risk index (RR) for IHD outcomes. In our study, AirQ software was used. The number of excess cases in Bishkek and Ahvaz for total mortality and cardiovascular mortality was 63 and 758 and 35 and 478 persons while for HARD and HACD was 84 and 2054 and 33 and 560 persons, respectively. The survey requires the need to enact and enforce permissible PM₁₀ levels/standards due to dust storms to reduce the health effect on humans by relevant environmental authorities both at federal and state levels.
显示更多 [+] 显示较少 [-]Evaluation of energy and electrode consumption of Acid Red 18 removal using electrocoagulation process through RSM: alternating and direct current 全文
2021
Payami Shabestar, Mahsa | Alavi Moghaddam, Mohammad Reza | Karamati-Niaragh, Elnaz
This study aims to evaluate energy and electrode consumption for Acid Red 18 (AR18) removal and the operating costs employing alternating current (AC) and direct current (DC) in an electrocoagulation (EC) system. As the novelty of this study, the effects of AC/DC mode and electrode type were scrutinized through a series of designed experiments in a batch EC reactor to remove a globally used Azo dye from wastewater. In this regard, by designing the experiments with response surface methodology (RSM), four series of 30 experiments were separately conducted employing DC and AC for iron (Fe) and aluminum (Al) electrodes. In each series, quadratic models were achieved for the removal efficiency and operating costs; by confirming the accuracy of the models, two responses were simultaneously optimized accordingly. As a result, the AR18 removal efficiency with Al electrodes had no significant difference using AC and DC (on average 0.2% difference); however, for Fe electrode, the EC performance in DC was more significant than AC (on average 13.8% difference). Also, the operating costs of Fe electrode were more economical in comparison with the Al; on average, the operating costs in the case of applying DC for Fe and Al were achieved 14.6 and 39.8 (US$/kg dye removed), respectively; whereas, for AC, this amount was calculated 9.3 and 36.0 (US$/kg dye removed) for Fe and Al, respectively.
显示更多 [+] 显示较少 [-]Evaluation of essential and non-essential elemental composition of commonly used medicinal plants from district Peshawar, Khyber Pakhtunkhwa, Pakistan 全文
2021
Malook, Khan | Ihsan-Ul-Haque,
This study illustrates a profile of some essential and non-essential elements (Na, K, Mg, Ca, Cu, Zn, Mn, Fe, Pb, Cr, Cd, Co, Al, and Sn) in the aerial parts of six medicinal plants, i.e. Coriandrum sativum L., Mentha spicata L., Papaver somniferum L., Calotropis gigantean (L.) Dryand., Withania coagulans (Stock) Dunal, and Fagonia arabica L. widely consumed in district Peshawar, the capital city of Khyber Pakhtunkhwa, Pakistan. The samples were converted into liquid state via wet digestion method and analyzed for elemental composition by using atomic absorption spectrometry. After determining the concentration, hazard quotient (HQ) was calculated for the elements having available maximum permissible limit set by FAO/WHO or any other agency for 50 mg daily intake of the herbal plants by a person of body mass 70 kg. K/Na ratio for the studied plants varied between 14.88:1 and 113.75:1 which was in agreement with the reported permissible range. The amount of Mg, Ca, Cu, and Co was within the permissible limit in all the enlisted plants. However, the HQ value for Mg and Ca was greater than the safe limit for some of the plants. The concentration and HQ value of Zn, Mn, Fe, Pb, Cr, and Cd was beyond the permissible and unsafe limits for almost all the plants. This study suggests that the plants of this area must be pretreated for lessening the concentration of some elements before consumption.
显示更多 [+] 显示较少 [-]Analysis of some factors related to dust storms occurrence in the Sistan region 全文
2021
Namdari, Soodabeh | Valizadeh Kamran, Khalil | Sorooshian, Armin
Dust storms over the Sistan region in East Iran are associated with predominant northwest winds (called 120-day winds) which promote desertification, including drying of the Hamoun wetlands. These storms are more frequent in spring and summer seasons in the Sistan region. The study aims to examine the relationship between vegetation cover and wind speed with dust storms intensity in order to understand the behavior of dust sources using satellite remote sensing data (AOD) between 2000 and 2019. Based on the time series, the study period can be divided into three parts based on the following characteristics: high dust intensity (2004), moderate relative intensity of value in all parameters studied (2005 to 2014), and dust reduction (2015–2019). Time series analysis shows a negative relationship between AOD and wind speed owing presumably to vegetative cover changes during years that wind speed has increased. Based on multiple regression analysis by monthly time scales that conforms time series result, monthly NDVI is significantly related to AOD. Analysis of the 3 hourly wind data suggests a positive relationship between wind and dust, and effective thresholds for dust erosion based on wind speeds are proposed for the Sistan region.
显示更多 [+] 显示较少 [-]Determinants of smallholder farmers’ choice on mulch film thickness in rural China 全文
2021
Li, Chang | Guo, Jianbing | Xu, Xiangbo | Sun, Mingxing | Zhang, Linxiu
Agricultural mulch film pollution has become a prevailing concern. Studies have shown that the thickness of mulch film is a key factor affecting mulch film recycling, but research about farmers’ choice on mulch film thickness is lacking. Based on survey data from 2025 households in five Chinese provinces in 2018, the Heckman two-stage model was used to analyze the influencing factors of farmers’ choice on mulch film thicknesses. Mulch film had been used by 21.98% of the sample households, and 41.47% of the used mulch film did not meet the national thickness standard. The econometric results showed that farmers’ product cognition and market factors were the two most important factors, and there was a significant negative correlation with the choice of film thickness. In addition, the choice of mulch film with different thicknesses was affected by household characteristics, subjective norms, and farmland property rights. Strengthening and stabilizing farmland property rights is a long-term mechanism to promote farmers to choose thicker mulch film. In addition to strengthening the production and sale of substandard film supervision, farmers’ choice of film thickness should be included in village regulations and other rural grass-roots governance systems, especially in the mechanism design between agricultural farmland protective subsidies and the prevention of mulch film pollution, rather than just considering the recycling itself.
显示更多 [+] 显示较少 [-]The influences of renewable electricity generation, technological innovation, financial development, and economic growth on ecological footprints in ASEAN-5 countries 全文
2021
Zeraibi, Ayoub | Balsalobre-Lorente, Daniel | Murshed, Muntasir
The Southeast Asian countries have experienced significant degrees of economic growth over the years but have not managed to safeguard their environmental attributes in tandem. As a result, the aggravation of the environmental indicators across this region casts a shadow of doubt on the sustainability of the economic growth achievements of the Southeast Asian countries. Against this milieu, this study specifically explores the influence of renewable electricity generation capacity, technological innovation, financial development, and economic growth on the ecological footprints in five Southeast Asian countries namely Indonesia, Malaysia, the Philippines, Thailand, and Vietnam during the period 1985–2016. One of the major novelties of this study is in terms of its approach to assess the renewable energy use-ecological footprint nexus using the renewable electricity generation capacity as an indicator of renewable energy use in the selected Southeast Asian nations. The econometric analysis involves methods that are robust to handling cross-sectional dependency and slope heterogeneity issues in the data. Accordingly, the recently developed Cross-sectional Augmented Autoregressive Distributed Lag estimator is used to predict the short- and long-run impacts on ecological footprints. The major findings suggest that higher renewable electricity generation capacity and technological innovation reduce ecological footprints, while higher financial development and economic growth increase the ecological footprints. Therefore, these findings imply that in forthcoming years, the selected Southeast Asian countries will need to tackle the environmental adversities by enhancing their renewable electricity generation capacities, increasing investment in technological development, greening the financial sector, and adopting environmentally-friendly growth policies. Hence, the implementation of relevant policies, in this regard, can be expected to ensure complementarity between economic growth and environmental welfare across Southeast Asia.
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