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Modern agriculture practices reveal an increase in use of pesticides and fertilizers to meet the food demand of increasing
population which results in contamination of the environment. In India crop production increased to 100% but the cropping
area has increased marginally by 20%. Pesticides have played a major role in achieving the maximum crop production, but maximum
usage and accumulation of pesticide residues was highly detrimental to aquatic and other ecosystem. The present study was
chosen to know the level of organochlorines contamination in ground water of Thiruvallur district, Tamil Nadu, India. The
samples were highly contaminated with DDT, HCH, endosulfan and their derivatives. Among the HCH derivatives, Gamma HCH residues
was found maximum of 9.8 μg/l in Arumbakkam open wells. Concentrations of pp-DDT and op-DDT were 14.3 μg/l and 0.8 μg/l. The
maximum residue (15.9 μg/l) of endosulfan sulfate was recorded in Kandigai village bore well. The study showed that the ground
water samples were highly contaminated with organochlorine residues. 相似文献
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Balu Soundara Vasudevan Mangottiri Pillai Rakesh J. Bhuvaneshwari S. Preethi V. Jeevanantham V. 《Environmental science and pollution research international》2022,29(57):85839-85841
Environmental Science and Pollution Research - 相似文献
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Sewage sludge contains rich organic matter and nutrients essential for the growth of plants but the presence of toxic heavy metals restricts its land application. To overcome this, the study aims an eco-friendly approach for leaching out heavy metals. Sewage sludge from sewage treatment plant, Chennai, India was characterised. The analysis of total heavy metal concentration was done by digesting in nitric acid and different forms were extracted by community bureau of reference sequential method. Heavy metals: As, Cd, Cr, Cr, Ni, Pb and Zn were determined using inductively coupled plasma optical emission spectrometry Perkin Elmer Optima 5300 DV. The experimental set-up for heavy metal leaching was held for five consecutive days at different concentrations of humic acid (0.1%, 0.5% and 1%) at varied pH (5–9). Results revealed that at the end of fifth day at pH 8, 1% humic acid is capable of leaching out 75.5% cadmium, 66.0% nickel, 52.0% lead, 51.2% zinc, 31.2% copper and 8.5% cadmium from sewage sludge. Statistically positive correlation (0.7088) existed between the percentage of heavy metals leached out and the sum of soluble and reducible fractions. Thus, from ecological point of view, humic acid can be used to leach out heavy metals from sewage sludge serving the need in restoration of soil fertility upon land application. 相似文献
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This article reviews both the pollution by the electrochemical industry and the use of electrochemistry to clean water. Main pollutants include Pd, Cd, Ni, Hg and other metals and cyanide as well as organic pollutants. The cause for water pollution by electrochemistry is due to the effluents from different electrochemical industries such as mercury from chlor-alkali industry; lead, cadmium and mercury from battery industry; heavy metals and organic contaminants from electroplating wastes; contaminants from corrosion processes; and persistent organic pollutants from the synthesis and use of pesticides, dyes and pharmaceuticals. Most pollutants can be successfully eliminated or converted to non-toxic materials by methods based on the electrochemical principles. Electrochemical depolluting methods are mainly electrodialysis, electrocoagulation, electroflotation, anodic processes, cathodic processes and electrochemical advanced oxidation processes. 相似文献
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Anirban Dutta Venugopal Vasudevan Lata Nain 《Journal of environmental science and health. Part. B》2016,51(1):24-34
An enrichment culture was used to study atrazine degradation in mineral salt medium (MSM) (T1), MSM+soil extract (1:1, v/v) (T2) and soil extract (T3). Results suggested that enrichment culture required soil extract to degrade atrazine, as after second sequential transfer only partial atrazine degradation was observed in T1 treatment while atrazine was completely degraded in T2 and T3 treatments even after fourth transfer. Culture independent polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) technique confirmed selective enrichment of genus Bacillus along with Pseudomonas and Burkholderia. Degradation of atrazine/metabolites in the industrial wastewater was studied at different initial concentrations of the contaminants [wastewater-water (v/v) ratio: T1, 1:9; T2, 2:8; T3, 3:7; T4, 5:5 and T5, undiluted effluent]. The initial concentrations of atrazine, cyanuric acid and biuret ranged between 5.32 and 53.92 µg mL?1, 265.6 and 1805.2 µg mL?1 and 1.85 and 16.12 µg mL?1, respectively. The enrichment culture was able to completely degrade atrazine, cyanuric acid and biuret up to T4 treatment, while no appreciable degradation of contaminants was observed in the undiluted effluent (T5). Inability of enrichment culture to degrade atrazine/metabolites might be due to high concentrations of cyanuric acid. Therefore, a separate study on cyanuric acid degradation suggested: (i) no appreciable cyanuric acid degradation with accumulation of an unidentified metabolite in the medium where cyanuric acid was supplemented as the sole source of carbon and nitrogen; (ii) partial cyanuric acid degradation with accumulation of unidentified metabolite in the medium containing additional nitrogen source; and (iii) complete cyanuric acid degradation in the medium supplemented with an additional carbon source. This unidentified metabolite observed during cyanuric acid degradation and also detected in the enrichment culture inoculated wastewater samples, however, was degraded up to T4 treatments and was persistent in the T5 treatment. Probably, accumulation of this metabolite inhibited atrazine/cyanuric acid degradation by the enrichment culture in undiluted wastewater. 相似文献
27.
Recovery of hydrogen and removal of nitrate from water by electrocoagulation process 总被引:1,自引:0,他引:1
Jothinathan Lakshmi Ganapathy Sozhan Subramanyan Vasudevan 《Environmental science and pollution research international》2013,20(4):2184-2192
The present study provides an optimization of electrocoagulation process for the recovery of hydrogen and removal of nitrate from water. In doing so, the thermodynamic, adsorption isotherm, and kinetic studies were also carried out. Aluminum alloy of size 2 dm2 was used as anode and as cathode. To optimize the maximum removal efficiency, different parameters like effect of initial concentration, effect of temperature, pH, and effect of current density were studied. The results show that a significant amount of hydrogen can be generated by this process during the removal of nitrate from water. The energy yield calculated from the hydrogen generated is 3.3778 kWh/m3. The results also showed that the maximum removal efficiency of 95.9 % was achieved at a current density of 0.25 A/dm2, at a pH of 7.0. The adsorption process followed second-order kinetics model. The adsorption of NO 3 ? preferably fitting the Langmuir adsorption isotherm suggests monolayer coverage of adsorbed molecules. Thermodynamic studies showed that adsorption was exothermic and spontaneous in nature. The energy yield of generated hydrogen was ~54 % of the electrical energy demand of the electrocoagulation process. With the reduction of the net energy demand, electrocoagulation may become a useful technology to treat water associated with power production. The aluminum hydroxide generated in the cell removes the nitrate present in the water and reduced it to a permissible level making the water drinkable. 相似文献
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Vasudevan Mangottiri Natarajan Narayanan Selvi Sugashini Masillamani Ravikumar Kesavan Rajendran Arun Dharshini Bagavathi Anushya Banu 《Environmental science and pollution research international》2022,29(57):86126-86155
Environmental Science and Pollution Research - The present study focuses on the impact of early imposed lockdowns and following unlocking phases on the status of air quality in six Tier-I and nine... 相似文献
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Rout Sonam Priyadarshini Vasudevan Sivaprakasam 《Environmental monitoring and assessment》2022,194(4):1-25
Environmental Monitoring and Assessment - The increased usage of antibiotics over the recent years has been of great concern all over the world. It is estimated that about 100,000 tons to 200,000... 相似文献
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