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991.
The objective of this study was to determine the blood lead level (BLL) of children aged under 5 living in western Uttar Pradesh, India. A total of 100 blood samples, 100 drinking water samples, and 21 vegetable samples were assessed for lead (Pb) contamination. BLL was observed in the range of 3–11.58?µg?dL?1 with a maximal level of 11.58?±?0.05?µg?dL?1 in Kazipur village. Lead in water samples was detected in the range of 0.006–0.095?ppm and identified at upto 9.5-fold higher than the stated permissible limit. A significant positive correlation (+0.679) was obtained between BLL and water Pb levels. All vegetable samples were also contaminated with Pb upto 12-fold higher than the permissible limit of 2.5?µg?g?1 of Prevention of Food Adulteration Act (PFA) 1954. Untreated industrial effluents were identified as the responsible factors for Pb occurrence in the study area. The presence of lead may be associated with the increased antisocial activities of children living in western Uttar Pradesh. Children with elevated BLL had poorer nutritional status than those with background Pb levels. There is an urgent need for a national campaign to monitor the BLL of children in India. 相似文献
992.
Mohammad Fareed Chandrasekharan Nair Kesavachandran Manoj Kumar Pathak Vipin Bihari Mohammed Kuddus 《毒物与环境化学》2013,95(8):1601-1609
In this study, risk assessment for visual disturbances among farm workers spraying agricultural pesticides in farms have been assessed. A cross-sectional study for the assessment of visual disturbances was undertaken using questionnaire survey and clinical examination among agricultural workers exposed to pesticides. Two hundred and thirty nine pesticide sprayers participated in the study. The study was compared to 110 controls not occupationally exposed to pesticides with similar socio-economic status. The prevalence of ocular morbidity was found to be 40% among pesticide sprayers which was significantly higher (p?0.01) as compared to controls. The symptoms among morbid subjects were found to be blurred vision, lacrimation, pain in eyes, red swollen eyes, and irritation of eyes. Exposure wise assessment of ocular symptoms among pesticide sprayers illustrates that exposure time elevates the ocular problems among sprayers. The cholinesterase activity was found to be significantly depleted (p?0.01) among pesticide sprayers as compared to controls which show the exposure of organophosphate pesticides among them. The visual disturbances observed among pesticide sprayers clearly exhibit that eyes get exposed by pesticides during spraying operations in agriculture and eventually get affected leading to ocular illness. 相似文献
993.
Organophosphorous compounds (OP) have largely been used as pesticides globally. These chemicals induce oxidative stress as a possible mechanism of action, which has been a focus of toxicological research for the last decade. This review evaluated the presence of oxidative stress, balance between total antioxidant capacity, and oxygen free radicals associated with OP compound exposure. Oxidative stress induced by OP leads to disturbances in function of different organs and tissues. Evidence indicates that stimulation of free radical production, induction of lipid peroxidation, and disturbance of the total antioxidant capacity are mechanisms of toxicity induced by most OP. Thus, use of antioxidants may be beneficial in treatment of OP poisoning, which remains to be elucidated with further clinical trials. 相似文献
994.
Akhilesh Kumar Yadav Sunil Kumar Sahoo Aditi Chakrabarty Patra Jay Singh Dubey Pradyumna Lenka D. Vidya Sagar 《毒物与环境化学》2013,95(3):410-425
Particulate matter concentrations were measured in an industrial region in the Ganjam district of Odisha. The average levels of suspended particulate matter (SPM) were measured to be 142 ± 8 and PM10 of particulate matter with a size of less than 10 micrometers (PM10) to be 50 ± 15 μg m?3. Out of the 14 elements determined, Ca, Na, Mg, Fe, and K contributed more than 95% of the total weight. In enrichment factors, the trace elements, i.e., Zn, Pb, Cd, and Hg were observed to be highly enriched in the SPM and PM10. Factor analysis indicates that more than 75% of the variance was due to five component factors, which have eigenvalues greater than 1. Intake of elements through inhalation route to adults has been estimated. 相似文献
995.
Ozonolysis combined with photocatalysis was used as a new approach for the treatment of textile dye wastewater containing azo dyes. The color reduction was very fast when only ozone was used for the treatment, but a 90% Total Organic Carbon (TOC) reduction was obtained only during a combined treatment. Reactive Black 5 dye containing two different percentages of NaCl was used for the experiment. The color reduction was fast in the neutral and basic pH. However for a fast TOC reduction acidic pH was found to be more effective. On‐line UV‐Vis spectrophotometry was used to measure the color reduction. 相似文献
996.
997.
K. S. Sanil Kumar P. M. Salas K. J. Prashob Peter C. S. Ratheesh Kumar 《Chemistry and Ecology》2016,32(2):117-135
Distribution (seasonal and spatial) of aliphatic and polycyclic aromatic hydrocarbons (PAHs) in surface sediments of the Chitrapuzha River, Cochin, India, was investigated using gas chromatography. Significantly high concentrations prevailed during the pre-monsoon season with the industrial zones of the river appearing to be hot spots with particularly elevated levels of the hydrocarbons. AHCs ranged between 7754 and 41,173?ng/g with an average of 25,256?ng/g, while total PAHs varied from 5046 to 33,087?ng/g. n-Alkane indices and PAH diagnostic ratios point to petroleum contamination in the sediments. The significance of PAHs in the sediments was explored using universally accepted interpretation tools. Observed levels of PAHs in sediments of Chitrapuzha are likely to cause adverse effects on biota. 相似文献
998.
This study emphasizes on identification of source and accessing the spatial variation of dissolved heavy metals (Cu, Cd, Fe, Ni, Pb and Zn) in the rivers of Sundarban Biosphere Reserve India, the UNESCO world heritage site. ANOVA (Analysis of Variance), PCA (Principal Component Analysis) as well as FA (Factor Analysis) are used for assessing the significant difference in means of metals concentration among the sites and understanding the sources of these pollutants. Three principal components with cumulative variance of 32, 55, and 73 %, show that Pb, Ni and Cd are closely associated with each other indicating an anthropogenic origin of these metals. Heavy metal evaluation index (HEI) values indicate that areas close to densely populated sites are affected by elevated metals concentration due to anthropogenic activities. The ratio between the concentration of Cd, Ni and Pb in sites and the maximum respective permissible limit for these metals for conserved habitat is Log10 normalized to understand the threats of these pollutants over the distributaries of Sundarbans. Pb pollution is prevalent in the areas that rely on the fossil fuel-operated boats, for transport, whereas higher Cd concentration is found in the areas dependent on rechargeable batteries to meet their energy demand. So these anthropogenic activities and mal-practices may be responsible for the heavy metal pollution in this region. The study concludes that gradual increase in metal pollution in river water due to anthropogenic activities, particularly Pb and Cd, could have a negative impact on the conserved flora and fauna of this ecosystem. 相似文献
999.
J. S. Yogesh Kumar N. Marimuthu S. Geetha Ch. Satyanarayana K. Venkataraman R. D. Kamboj 《Journal of Coastal Conservation》2014,18(3):167-175
The Gulf of Kachchh is characterised by a strong tidal variation and the reef communities are capable of higher exposure time during negative tides. About 11 sites located along the Marine National Park (MNP) from west to east were studied for assessing the present status of live coral cover along with other life-form categories. In the present study, the maximum live coral cover was recorded in Pirotan Island, followed by Laku Point, Mithapur and Boriya reef. Multivariate analyses such as Principal Component Analysis and Correspondence Analysis supported that the contribution of live coral cover was more towards Pirotan Island whereas the contribution of coral species cover was more towards Laku Point. Bray-Curtis cluster analysis categorized all the study sites into four major clusters with 78 % similarity based on life-form categories. Among them, two clusters from western region (one forming site from Mithapur Reef to Lakku Point and another one forming from Ashaba Gugar Reef to Dabdaba Island), the third one combines the western and eastern regions (Boriya Reef to Kalubar Island), the fourth one comprises the eastern region (Narara Reef to Sikka), and one outlier Pirotan Island. Based on coral species cover, two major clusters with 55 % similarity were formed. Among them, one cluster was formed from Pirotan Island to Kalubar Island in the eastern side of MNP and the second one comprised the western region of MNP (Boriya Reef to Laku Point), and one outlier Mithapur Reef. Thirty one species of live corals belonging to 8 families and 18 genera were recorded in the Marine National Park itself during the study period. 相似文献
1000.
Anubhav Kaphle P. N. Navya Akhela Umapathi Hemant Kumar Daima 《Environmental Chemistry Letters》2018,16(1):43-58
Nanotechnology is expected to have a beneficial influence on agriculture, food and environment, due to the unique properties of nanomaterials. However, little is known about their safety and potential toxicity. Here we review metal nanoparticles, nanometal oxides, carbon nanotubes, liposomes and dendrimers. We present the application of these nanomaterials in agriculture, food and environment for plant protection; disease treatment; packing materials; development of new tastes, textures and sensations; pathogen detection; and delivery systems. We discuss risk assessment of nanomaterials and toxicological impacts of nanomaterials on agriculture, food and environment. We then provide regulatory guidelines for the safer use of nanomaterials. 相似文献