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Metal concentrations in fish from nine lakes of Anhui Province and the health risk assessment 全文
2020
Yin, Jiaojiao | Wang, Li | Liu, Qi | Li, Sai | Li, Jian | Zhang, Xuezhen
In the present study, to comprehensively investigate the metal contamination in the fish of Anhui Province, four fish species, Ctenopharyngodon idella, Cyprinus carpio, Hypophthalmichthys molitrix, and Hypophthalmichthys nobilis, were collected from nine lakes, and the levels of Zn, Pb, Cr, Cu, Ni, As, Hg, and Cd in the fish muscle were determined. The results showed that the highest concentrations of Zn (7.791 mg/kg), Pb (0.522 mg/kg), Cr (0.030 mg/kg), and Cu (0.767 mg/kg) were found in Tiangang Lake, Xifei Lake, Tiangang Lake and Baidang Lake, respectively. However, metals Ni, As, Hg, and Cd were not detected in all fish samples. In the fish species, the metal bioaccumulation ability was decreased with the following order: C. idellus > H. molitrix > H. nobilis > C. carpio. Furthermore, the target hazard quotient (THQ) was used to assess the health risk via fish consumption. The results indicated for co-exposure; C. idellus would pose a health risk to children at high exposure level (95th) as THQ value was higher than 1. It should be pointed out that Pb contributes most to the total THQs (the ratio was 88%); thus, the contamination of Pb should be paid more attention. This field investigation combined with health risk assessment would provide useful information on the heavy metal pollution in Anhui Province.
显示更多 [+] 显示较少 [-]Respiratory health disorders associated with occupational exposure to bioaerosols among workers in poultry breeding farms 全文
2020
Younis, Faten | Salem, Eman | Salem, Eman
Working in poultry farms revealed the exposure to chemical and biological emissions (bioaerosols) that might be related to respiratory diseases in the workers and an increased loss in lung function. The current study aimed to determine the respiratory health status among poultry farm workers and to monitor the biological and the environmental conditions at ten poultry farms in Egypt. It reported that the total dust, ammonia (NH₃), and carbon dioxide (CO₂) concentrations in the studied poultry farms did not exceed the permissible exposure limits except farm V where NH₃ was slightly exceeded the recommended levels. 35.7% of the poultry farm workers had positive nose and throat culture (bacterial and fungal). The poultry farm workers had higher prevalence of cough, wheeze, and shortness of breath with lower mean values of spirometric measurements than the controls (P < 0.05). Also, the positive culture poultry farm workers had significantly higher respiratory manifestations and lower spirometry values than negative culture ones (P < 0.05). Therefore, intervention programs for reducing the exposure are amendatory point for the health and safety of poultry farm workers.
显示更多 [+] 显示较少 [-]Salicylic acid application alleviates the adverse effects of triclosan stress in tobacco plants through the improvement of plant photosynthesis and enhancing antioxidant system 全文
2020
Guan, Chunfeng | Wang, Chang | Wu, Hao | Li, Qian | Zhang, Yue | Wang, Gang | Ji, Jing | Jin, Chao
Triclosan (TCS) is a chlorophenol which is highly bacteriostatic and used in a wide array of consumer products. TCS is now one of the most commonly detected organic pollutants in the sewage sludges. The sludge utilization for fertilizers on agricultural land would pose the risk of causing adverse effects on plant growth and yield by TCS. However, the toxicity of TCS toward plants is comparatively less understood. In this study, we assessed the effects of TCS on tobacco plants which were grown in MS medium or soils containing various concentrations of TCS. Our results indicated that TCS at the concentration of 2 mg/L could strongly inhibit the tobacco seed germination. TCS could suppress tobacco plant growth in soil with different concentrations (10, 20, and 50 mg/kg) of TCS through the downregulation of chlorophyll contents, restricting photosynthesis and increasing generation of reactive oxygen species (ROS). Salicylic acid (SA) plays important roles in the stress response of plants. The role of exogenous SA application in protecting tobacco plants from TCS stress was also investigated in this study. SA application could significantly increase net photosynthesis, enhance antioxidant enzyme activity, and thereby enhancing tobacco plant tolerance to TCS. Moreover, the activation of MPK3 and MPK6 induced by TCS was downregulated in plants with the treatment of SA. It was thus referred that mitogen-activated protein kinases (MAPKs) might play a key role in the signal transduction of TCS stress, and this process might be regulated by SA signaling. Overall, our results demonstrated that TCS had negative impacts on tobacco plants and SA played a protective role on tobacco plants against TCS stress.
显示更多 [+] 显示较少 [-]Maximum contaminant level of arsenic in drinking water potentiates quinalphos-induced renal damage on co-administration of both arsenic and quinalphos in Wistar rats 全文
2020
Singh, Parvinder | Verma, Pawan Kumar | Raina, Rajinder | Sood, Shilpa | Sharma, Priyanka
This study was designed to determine alterations in renal biomarkers, antioxidant profile, and histomorphology of renal tissue following subacute exposure to quinalphos alone or in conjunction with arsenic in rats. A total of 54 adult Wistar rats were randomly divided into nine groups of six rats each and were administered sub-lethal concentrations of quinalphos (1/100ᵗʰ and 1/10ᵗʰ of LD₅₀) orally daily and arsenic (50 and 100 ppb) in drinking water for 28 days. Significantly (p < 0.05) decreased levels of antioxidant biomarkers in renal tissue, viz., total thiols, catalase, superoxide dismutase, glutathione peroxidase, glutathione-s-transferase, and glutathione reductase along with increased (p < 0.05) thiobarbituric acid reacting substance (TBRAS) levels indicated that significant oxidative damage to renal tissue occurred following repeated administrations of quinalphos at either dose levels or arsenic at the concentration of 100 ppb when compared with the control rats. The alterations in the antioxidant parameters were observed to be more pronounced in co-administered groups as compared with either toxicant administered group. Similarly, activity of renal acetylcholinesterase was decreased after repeated exposure to quinalphos or arsenic, but inhibition was higher (up to 48%) in rat renal tissue co-exposed with quinalphos and arsenic at the higher concentration. These findings corroborated with the histopathological alterations in renal tissue of toxicant exposed rats. The altered plasma and tissue antioxidant biomarkers along with histopathological changes in the kidney at higher dose level of either toxicant indicate that renal tissue is significantly impacted by these toxicants, and these effects become more pronounced after their co-administration.
显示更多 [+] 显示较少 [-]Macroelement, trace element, and toxic metal levels in leaves and infusions of yerba mate (Ilex paraguariensis) 全文
2020
Olivari, Ilaria | Paz, Soraya | Gutiérrez, Ángel J. | González-Weller, Dailos | Hardisson, Arturo | Sagratini, Gianni | Rubio, Carmen
Mate is an infusion made from the dried leaves of yerba mate (Ilex paraguariensis). Yerba mate may be an important source of essential elements but could contain toxicologically relevant metals. Macroelements (Ca, Mg, Na, K), trace elements (B, Ba, Sr, V, Li, Ni, Fe, Zn, Cu, Cr, Co, Mn, Mo), and toxic metals (Al, Cd, Pb) content have been determined in 32 samples of yerba mate by ICP-OES (inductively coupled plasma—optical emission spectrometry) with the aim of determining the element content of yerba mate leaves and the influence of temperature in the extraction of these elements from the plant to the infusion, and estimating the dietary intake for each element studied. The highest element contents have been found in infusions prepared with hot distilled water (70–75 °C); the most noteworthy are K (303 mg/L), Mn (4.85 mg/L), and Al (4.52 mg/L). The consumption recommended by the producers (500 mL infusion/day) contributes significantly to the daily intake of essential elements such as Mn, Mg, and Cu. This consumption does not pose a health risk, although it is necessary to assess the risk/benefit of Ni intake from mate consumption for people with impaired renal function (500 mL/day accounts for 52.2% of the TDI).
显示更多 [+] 显示较少 [-]Impact of industrial activities on atmospheric volatile organic compounds in Sihwa-Banwol, the largest industrial area in South Korea 全文
2020
Kim, Min-ji | Seo, Young-Kyo | Kim, Chong-ho | Baek, Sung-Ok
The impact of industrial activities on atmospheric volatile organic compounds (VOCs) in the Sihwa-Banwol complexes, i.e., the largest industrial area in Korea, was investigated. More than 60 VOCs were determined from 850 samples collected from four sites in and around the complexes through a 2-year monitoring campaign from 2005 to 2007. The VOCs of particular concern found in the area were benzene, toluene, ethylbenzene, xylenes, trichloroethylene, and formaldehyde, given their toxicity, concentration, and detection frequency. Toluene was the most abundant one. The VOC concentration rankings were consistent with their emission rankings. Most VOCs had higher concentrations at the industrial sites than at residential sites, indicating a significant impact of industrial emissions. The ambient levels of benzene and formaldehyde were additionally affected by vehicular emissions and secondary formation, respectively. Overall, the VOC levels increased in winter and at night, because of the local weather conditions. In contrast, the formaldehyde concentration increased in summer, owing to its secondary formation in the atmosphere. The ambient VOC levels in Sihwa-Banwol were higher than those in other parts of Korea. Additionally, the cumulative cancer risks posed by the toxic VOCs exceeded a tolerable risk level of 1 × 10⁻⁴ in not only the industrial areas but also the residential areas. The sum of the non-cancer risks in both areas significantly exceeded the threshold criterion of 1. The large amounts of aromatic compounds emitted from the industrial complexes are believed to play a crucial role in the elevated levels of surface ozone in the Seoul metropolitan area during the summer season. Therefore, comprehensive measures for controlling the VOC emissions in the Sihwa-Banwol area need to be prioritized to reduce the health risks for residents of not only this area but also the capital Seoul and its surrounding areas.
显示更多 [+] 显示较少 [-]An environmental assessment model of construction and demolition waste based on system dynamics: a case study in Guangzhou 全文
2020
Liu, Jingkuang | Liu, Yedan | Wang, Xuetong
At present, China is in the rapid development stage of urbanization, and construction activities are becoming more frequent. This is accompanied by a large amount of construction and demolition waste (C&DW), which raises many problems with its governance, such as occupying valuable land resources, causing air pollution, and consuming raw materials. In this study, taking Guangzhou as an example, the system dynamics principle was used to establish an environmental assessment model of C&DW, and Vensim software was used to simulate and analyze the environmental, economic, and social impacts of various disposal methods of C&DW. The results showed that (1) among all waste disposal methods, landfill disposal had the highest greenhouse gas emissions. It was estimated that the greenhouse gas emissions from landfill disposal will account for 75% of the total emissions in 2030, while the greenhouse gas emissions from recycling disposal will only account for 0.5%. (2) The simulation results showed that, according to the current data, the land area occupied by waste landfills and illegal dumping in 2030 will be about 4.88 million m², and the economic loss caused by land loss and global warming will account for 9.1% of Guangzhou’s GDP in 2030, which is equivalent to the national economy of a regional city with a less developed economy. (3) Enhanced supervision could significantly reduce the amount of illegal dumping, but its effect on landfill disposal and recycling would be very limited. According to the results of the simulation analysis, some suggestions were put forward to improve the environmental, economic, and social impact of C&DW disposal in Guangzhou.
显示更多 [+] 显示较少 [-]A study of environmental regulation, technological innovation, and energy consumption in China based on spatial econometric models and panel threshold models 全文
2020
Zhou, Huan | Qu, Shaojian | Wu, Zhong | Ji, Ying
Under different technological innovation modes, regional energy consumption may have spatial heterogeneity. Spatial heterogeneity complicates the nexus between environmental regulation and energy consumption. Traditional spatial homogeneity analysis is hard to describe the nonlinear nexus between them. Based on the data of 30 provinces in China from 2007 to 2017, this paper employs the spatial econometric method and the nonlinear econometric method to investigate the spatial effects and nonlinearity of energy consumption, respectively. The results display that under the current level of economic development, per capita energy consumption has a significant spatial spillover effect. Environmental regulation promotes regional per capita energy consumption in the short term. On the contrary, the technological effect of environmental regulation has significantly reduced Chinese per capita energy consumption. Therefore, energy policy should be tailored to local conditions, and policymakers can strengthen the environmental regulatory system and encourage enterprises to implement green technology innovation.
显示更多 [+] 显示较少 [-]Impact of biomass combustion on occurrence and distribution of aromatic hydrocarbons in apples 全文
2020
Paris, Alice | Gaillard, Jean-Luc | Ledauphin, Jérôme
Forest fires and biomass burning are known to generate aromatic hydrocarbons via incomplete combustions, due to high moisture, insufficient temperature, and oxygen content. These emission sources are particularly concerning because generated smokes cannot be treated and aromatic hydrocarbons can deposit on plant foods.The aim of this work was to study the potential deposition and absorption of monocyclic and polycyclic aromatic hydrocarbons in plant after exposure to smokes generated by burning wood. Thus, apples, used as a representative plant food model, were intentionally exposed to wood burning emissions for lengths of time varying from 1 to 2 h. Among benzene, toluene, ethylbenzene, xylenes, toluene appeared to be the most abundant compound. Concerning PAHs, linden wood combustion led to predominant deposition of compounds with molecular weights lower than 202 g/mol with the highest levels detected for phenanthrene.Aromatic hydrocarbons from wood combustion were mainly deposited on apple epicarp, and their transfer to the mesocarp was limited. Diagnostic ratio, used for the determination of PAHs emission source, was calculated with PAHs contents deposited on apple skin. Results were consistent with values proposed in the literature for the identification of biomass combustion.
显示更多 [+] 显示较少 [-]Promising insecticidal efficacy of the essential oils from the halophyte Echinophora spinosa (Apiaceae) growing in Corsica Island, France 全文
2020
Pavela, Roman | Maggi, Filippo | Cianfaglione, Kevin | Canale, Angelo | Benelli, Giovanni
Promising insecticidal efficacy of the essential oils from the halophyte Echinophora spinosa (Apiaceae) growing in Corsica Island, France 全文
2020
Pavela, Roman | Maggi, Filippo | Cianfaglione, Kevin | Canale, Angelo | Benelli, Giovanni
Echinophora spinosa (Apiaceae) is a psammophilous species growing along Mediterranean coastal sand dunes. This species secretes essential oils made up of monoterpenoids, phenylpropanoids, and polyacetylenes, which may represent effective, eco-friendly and safe active ingredients for the preparation of green insecticides. Based on this, in the present study, we selected a French accession of E. spinosa growing on the coastal dunes of Corsica, extracting the essential oils from aerial parts and roots by hydrodistillation. The essential oils were analyzed by GC-MS for chemical composition and screened for their insecticidal activity on three target insects, Culex quinquefasciatus, Spodoptera littoralis, and Musca domestica. The essential oil from roots was dominated by the phenylpropanoid myristicin and the monoterpene hydrocarbon terpinolene, with a minor contribution of (Z)-falcarinol. The oil from the aerial parts was characterized by monoterpenes, mainly p-cymene, a-phellandrene, and α-pinene. The root essential oil exhibited promising toxicity on the target insects, with special reference to C. quinquefasciatus larvae (LC₅₀ = 15.7 mg L⁻¹), while on M. domestica and S. littoralis, it showed LD₅₀ of 38.3 μg adult⁻¹ and 55.6 μg larva⁻¹, respectively. Based on our findings, E. spinosa can be viewed as a new potential crop to produce insecticidal essential oils in arid salty areas. However, synergistic and antagonistic effects of the major constituents of both oils tested here deserve future research. Further studies on the efficacy of stable formulations of the E. spinosa root essential oil, with special reference to micro- and nanoformulations, are ongoing.
显示更多 [+] 显示较少 [-]Promising insecticidal efficacy of the essential oils from the halophyte Echinophora spinosa (Apiaceae) growing in Corsica Island, France 全文
2020
Pavela, Roman | Maggi, Filippo | Cianfaglione, Kevin | Canale, Angelo | Benelli, Giovanni