خيارات البحث
النتائج 5001 - 5010 من 6,453
Health risks from trace elements in muscles of some commonly available fish in Australia and India النص الكامل
2020
Rahman, Mohammad Mahmudur | Shehzad, Muhammad Tahir | Nayak, Amaresh Kumar | Sharma, Shruti | Yeasmin, Marjana | Samanta, Srikanta | Correll, Ray | Naidu, R.
The levels of trace elements (As, Hg, Cr, Cd, Pb, Co, Ni, Cu, Mn and Zn) in commercially important fish species sampled from fish markets of Adelaide, Australia; canned fish from South Australian supermarkets; and fish markets of West Bengal, India were determined by inductively coupled plasma mass spectrometry (ICP-MS) after microwave digestion. Mercury was determined by using triple quadrupole ICP-MS. The accuracy of the methods was assessed with a certified standard reference material (NRCC-DORM-3 dogfish protein), and the results were compared with values reported in the literature. The results indicated considerable variations in the accumulation of trace elements among the fish species. The relationship between species with respect to trace element concentrations was examined using cluster analysis, which showed Indian fish species forming distinct groups from the others. Other than As in sardines, whiting and snapper and Hg in swordfish and snapper, the trace element concentrations were within permissible limits recommended by various standards. Based on the estimated daily intake (EDI), fish samples analysed in this study can be considered safe for human consumption as per the recommended daily dietary allowance limit fixed by various agencies. Continuous monitoring and assessments of fish metal(loid) content are needed to generate more data and safeguard human health.
اظهر المزيد [+] اقل [-]Carbon emissions in the transportation sector of Yangtze River Economic Belt: decoupling drivers and inequality النص الكامل
2020
Zhang, Lina | Chen, Donghui | Peng, Sha | Pang, Qinghua | Li, Fangjuan
Carbon emissions in the transportation sector are of great concern, since they are the third leading contributor to China’s carbon emissions. This research examines the decoupling relationship between economic outputs and carbon emissions of 11 provinces in 2000–2016 by focusing on Yangtze River Economic Belt (YREB), which is the densest traffic and economic corridor in China. Although many studies have focused on the decoupling state and its driving forces between economic outputs and carbon emissions, few studies further addressed the microscale analysis for decoupling drivers. This paper reveals the characteristic, inequality contribution ratio, and dynamic evolution of the drivers by integrating Dagum’s Gini ratio with kernel density estimation in YREB. Results are as follows: (1) The decoupling states presented weak decoupling state at the whole belt in the majority of the latter observed sub-periods. The decoupling states at the provincial level turned more satisfactory during the four observed sub-periods, especially for Shanghai and Zhejiang. (2) The energy intensity (EI) effect is the predominant driver for promoting the decoupling state in the vast majority of provinces, whereas value added per capita effect is the major role for inhibiting the decoupling state. (3) During the four observed sub-periods, the Gini inequality and transvariation intensity of the EI effect between sub-regions are the main sources of the provincial differences in YREB. The driving force of EI effect is increasing, but the provincial differences are expanding in the upstream and downstream regions by analyzing its dynamic evolution. Understanding the temporal and spatial microscale inequality of the decoupling drivers provides governments with differentiated and forward-looking suggestions towards coordinating regional economic growth and carbon emissions reduction.
اظهر المزيد [+] اقل [-]Zinc alleviates maneb-induced kidney injury in adult mice through modulation of oxidative stress, genotoxicity, and histopathological changes النص الكامل
2020
Sefi, Mediha | Chaâbane, Mariem | Elwej, Awatef | Bejaoui, Safa | Marrekchi, Rim | Jamoussi, Kamel | Gouiaa, Naourez | Boudawara Sellami, Tahia | El Cafsi, M’hamed | Zeghal, Najiba | Soudani, Nejla
Zinc is one of the important essential trace minerals to human health due to its antioxidant properties. The present study was conducted to elucidate its potential protective role against maneb-induced nephrotoxicity. For this purpose, animals were randomly divided into four groups of six each. Mice of group I (negative controls) have received daily 0.5 ml of distilled water, a solvent of maneb. Mice of group II (MB) have received 30 mg/kg bw of maneb daily by intraperitoneal way. Mice of group III (MB + Zn) have received the same dose of maneb as group II, along with ZnSO₄ (30 mg/kg bw) daily. Mice of group IV (Zn), considered as positive controls, have received the same dose of ZnSO₄ as group III daily. Our results revealed that ZnSO₄ co-administration to maneb-treated mice decreased kidney levels of malondialdehyde, hydrogen peroxide, protein carbonyls, and advanced oxidation protein products; the levels of non-enzymatic antioxidants like vitamin C, glutathione, and metallothionein. It recovered the alteration of antioxidant enzyme activities (catalase, superoxide dismutase, and glutathione peroxidase) and attenuated DNA fragmentation. Furthermore, this essential trace element was also able to alleviate kidney biomarkers’ alterations by lowering plasma levels of creatinine, urea, uric acid, and lactate dehydrogenase. In addition, the histopathological changes induced by maneb were improved following zinc administration. Our results indicated that zinc might be beneficial against maneb-induced renal oxidative damage in mice.
اظهر المزيد [+] اقل [-]Comparative study on adsorption and immobilization of Cd(II) by rape component biomass النص الكامل
2020
Hu, Zhao | Hu, Hongqing | Tang, Yafang | Dai, Yujun | Wang, Zefeng | Yan, Rui
Agricultural wastes have promising potential for the production of low-cost and sustainable adsorbents for heavy metals, while the characteristics of those biosorbents and the stability of the passivated heavy metals under natural conditions need to be studied further. In this paper, the oilseed rape plant after seed harvesting was divided into three parts: root (RT), stem (ST), and pod (PD). The isotherm adsorption of cadmium (Cd(II)) on the biomass was conducted. In practice, the biomass was aged in the Cd(II)-contaminated soil, and the concentration of Cd(II) in the leachate was measured after the continuous eluent of typical acid rain. The components and elements of the biomass were determined for the analysis of the differences between the immobilization abilities of the biomass. Results showed the CC (corn cob, as a comparison), ST, RT, and PD had the adsorption capacities of 6.34, 7.58, 9.22, and 9.87 mg/g for Cd(II) through the Langmuir fitting of the isothermal adsorption experiments, respectively. The leached Cd(II) were reduced 1063, 2073, 2824, and 3621 μg by CC, ST, RT, and PD biomass aging, respectively. Compared that by CC, the immobilization differences between the biomass in soil were much greater than that in isotherm adsorption, indicating the biosorption ability of rape biomass was enlarged during the 30 days of aging. Nitrogen, phosphorus, and sulfur contents showed sequences as pod>root>stem and had high correlations with the reduced amount of leached Cd(II), which indicated protein might be beneficial for the enhancement of adsorption/immobilization in the soil.
اظهر المزيد [+] اقل [-]Oxidative stress, hematological and biochemical alterations induced by sub-acute exposure to fipronil (COACH®) in albino mice and ameliorative effect of selenium plus vitamin E النص الكامل
2020
Abouelghar, Gamal E. | El-Bermawy, Zeinab A. | Salman, Hagar M. S.
Fipronil (FIP) is a highly effective, broad-use insecticide that belongs to the phenylpyrazole chemical group. It is extensively used in the agriculture and veterinary medicine for controlling a wide variety of pests. Though FIP showed lower toxicity in vertebrates than in insects, it was recognized to have a variety of toxic effects in mammals. The present study was undertaken to evaluate FIP-induced alterations in the blood biochemical markers and oxidative stress parameters in male albino mice via oral sub-acute toxicity exposure. The possible ameliorative effect of the pretreatment with selenium plus α-tocopherol (vitamin E) against the harmful effects of FIP was also investigated. Mice in FIP-test groups were exposed to different sublethal doses, i.e., 1.43, 2.87, and 4.78 mg active ingredient (AI)/kg body weight (b.w.), equal to 1/100, 1/50, and 1/30 LD₅₀ of FIP, respectively, for 28 days. Mice in the amelioration groups were orally administered with selenium + vitamin E (0.3 mg + 22.5 mg/kg b.w., respectively) 14 days prior to exposure to the higher dose (4.78 mg/kg) of FIP for another 14 days. Fipronil exposure at medium and high doses showed lowered values of red blood cell count (RBC), hematocrit (HCT), hemoglobin (HGB), white blood cell (WBC), and platelet (PLT) counts after 28-day exposure, compared to the control. All three doses caused significant increases in levels of liver-function biomarkers, i.e., aspartate amino transaminase (AST), alanine amino transaminase (ALT), alkaline phosphatase (ALP), cholesterol, and bilirubin levels compared to the control. Levels of biomarkers related to kidney functions, i.e., urea, uric acid, and creatinine, increased significantly than these of the control. Likewise, the oxidative stress indices, i.e., hydrogen peroxide (H₂O₂) and malondialdehyde (MDA), significantly increased at the higher and medium doses, while antioxidant enzymes, catalase (CAT) and superoxide dismutase (SOD), decreased significantly. On the other hand, prior administration of selenium + vitamin E in the FIP-exposed mice led to restore values of most hematological parameters nearly to these of the control. Also, the levels of AST, total protein, and creatinine seemed to be restored to the control values. Interestingly, pretreatment with selenium + vitamin E restored the levels of antioxidant enzymes, CAT and SOD, to the control values, whereas, oxidative stress indices, H₂O₂ and MDA, remained significantly high. It is our thought that the sublethal dose less than 1.43 mg/kg b.w. of commercial formulation of FIP (COACH® 200 SC) could be considered as no-observed-adverse-effect-level(NOAEL) under our present experimental conditions at short-term toxicity study. On the other hand, the higher sublethal doses, 4.78 and 2.87 mg/kg b.w., induced significant adverse effects in biomarkers and may be deleterious to human health following long-term exposure.
اظهر المزيد [+] اقل [-]Modelling environmental degradation in South Africa: the effects of energy consumption, democracy, and globalization using innovation accounting tests النص الكامل
2020
Usman, Ojonugwa | Olanipekun, Ifedolapo O. | Iorember, Paul Terhemba | Abu-Goodman, Maryam
This study investigates the effects of energy consumption, democracy and globalization on environmental degradation in the context of the environmental Kuznets curve (EKC) for South Africa between 1971 and 2014. To this end, the study applies the combined Bayer-Hanck cointegration test and the fully modified ordinary least squares (FM-OLS) estimation approach. The empirical results confirm the presence of cointegration among the variables, and thus validate the EKC hypothesis for South Africa. In addition, while energy consumption increases environmental degradation, the effect of democracy is positively insignificant. The finding also suggests that globalization condenses environmental degradation. The results of the long-run causal relationship divulge that economic growth, energy consumption, democracy and globalization Granger-cause environmental degradation. The results also find causality running from CO₂ emissions, economic growth, democracy and globalization to energy consumption. In the short run, a causality is found running from globalization to CO₂ emissions, energy consumption to CO₂ emissions and globalization to energy consumption. In addition, economic growth is said to Granger-cause democracy while democracy Granger-causes CO₂ emissions. These results are validated by the innovation accounting tests.
اظهر المزيد [+] اقل [-]Correction to: Investigation of organic material self-heating in oxygen-depleted condition within a coal-waste dump in Upper Silesia Coal Basin, Poland النص الكامل
2020
Nádudvari, Ádám | Fabiańska, Monika J. | Misz-Kennan, Magdalena | Ciesielczuk, Justyna | Kowalski, Adam
The original publication of this paper contains a mistake.
اظهر المزيد [+] اقل [-]Methanolic extract of Ephedra alata ameliorates cisplatin-induced nephrotoxicity and hepatotoxicity through reducing oxidative stress and genotoxicity النص الكامل
2020
Sioud, Fairouz | Ben Toumia, Imene | Lahmer, Aida | Khlifi, Rihab | Dhaouefi, Zaineb | Maatouk, Mouna | Ghedira, Kamel | Chekir-Ghedira, Leila
Cisplatin (CP) is a powerful anticancer agent used in the treatment of a diverse type of cancers. Oxidative stress is one of the most important side effects limiting the use of cisplatin. The protective effects of methanolic extract (ME) and ephedrine (EP), major compound, of Ephedra alata on CP-induced damages were here assessed. Treatment with CP-induced nephrotoxicity and hepatotoxicity characterized by biochemical alterations. In fact, using CP reduced significantly glutathione (GSH) levels, enzymatic activities of superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST), and increased malondialdehyde (MDA) content. Nonetheless, CP-treatment induced DNA damage at renal, hepatic, and blood cells and increased interferon gamma (IFNγ) level in serum. Co-treatments of mice with ME normalized relative kidney/body weight, restored biochemical and oxidative stress parameters, reduced DNA damage and IFNγ level. In conclusion, ME exhibited the best protective effect against CP damage compared with ephedrine. This is could be attributed to the presence of polysaccharides, organic acids, flavonoids, and tannins in addition to ephedrine alkaloids. These compounds were reported to play a major role in inhibiting and scavenging free radicals, providing an effective protection against CP- induced oxidative damage. Graphical abstract
اظهر المزيد [+] اقل [-]Evaluating the toxicity of polyurethane during marine clay stabilisation النص الكامل
2020
Saleh, Samaila | Ahmad, Kamarudin | Mohd Yunus, Nor Zurairahetty | Hezmi, Muhammad Azril
In civil engineering, many geotechnical and forensic projects employ polyurethane (PU) for ground improvement, and the results have shown to be effective in terms of time and cost savings. However, similar to many other chemical stabilisers, the use of PU for soil stabilisation may have environmental repercussions. Therefore, this paper utilised a toxicity characteristic leaching procedure (TCLP) to investigate the potential for ground contamination resulting from the application of PU for the stabilisation of marine clay. Furthermore, the hazardousness of PU during the stabilisation of marine clay was investigated by testing its reactivity, ignitability, corrosivity and physical properties. The results reveal that the quantity of heavy metals present in PU is far below the regulatory limits. The results further confirm that PU is odourless and non-corrosive and that it is non-cyanide and non-sulphide-bearing. However, PU is capable of igniting. Overall, the potential application of PU for ground improvement is promising due to its environmental friendliness.
اظهر المزيد [+] اقل [-]Pollution evaluation, spatial distribution, and source apportionment of trace metals around coal mines soil: the case study of eastern India النص الكامل
2020
Siddiqui, Azeem Uddin | Jain, Manish Kumar | Masto, Reginald Ebhin
The degradation of land by trace metals contamination around coal mining areas is a serious environmental issue, and therefore, it is necessary to have detailed information about the pollution caused by them and their sources. The objective of the work was to study the impact of trace metals (e.g., Cd, Co, Ni, Cr, Zn, Pb, and Cu) on the soil of Jharia coalfield to analyze their sources, contamination level, and their spatial distribution. The present values of the trace metals were compared by their natural background values which were then analyzed on the scale of the Potential Ecological Risk Index (PERI) and by Improved Nemerow Index (Lₙₘ). The results of spatial distribution revealed that the majority of the soil in Jharia coalfield is moderately contaminated, a small portion of it is slightly contaminated, and altogether at moderate ecological risk due to trace metals. Multivariate statistical techniques including Principal component analysis, Cluster analysis, and Pearson’s correlation evaluated that Cu, Ni, Zn, Co, and Cr in the soil samples had the same source which is coal mining; Pb and Cd were from multiple sources. The spatial distribution maps of trace metals present in the soil of Jharia coalfield were generated using Radial basis function an interpolation method.
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