Amberlite XAD-7 impregnated with morpholine dithiocarbamate as trace metal extractant

Application of Amberlite XAD-7 impregnated with morpholine dithiocarbamate (MDTC) for separation and preconcentration of trace amounts of lead, copper, cobalt, iron, nickel, cadmium and zinc and determination by ICP-AES has been described. The optimum experimental parameters, such as pH, sample flow rate, eluent and effect of matrix ions on the preconcentration were investigated. Simultaneous enrichment of the seven metals was accomplished. The t _1/2 values for sorption are 2.9, 3.3, 3.7, 3.6, 2.8, 4.1 and 2.8 respectively for Pb(II), Cu(II), Co(II), Fe(III), Ni(II), Cd(II) and Zn(II). The method was applied for the determination of trace metal ions in seawater and natural water samples. The results have been compared with extraction GFAAS method.     

Passive Samplers for NOx Monitoring: A Critical Review

Nitrogen oxide is an important gaseous air pollutant. It plays a major role in atmospheric chemistry, particularly in the formation of secondary air pollutants such as ozone, peroxyacyl nitrate (PAN), nitrate aerosols, and contributes to environmental acidification. A comprehensive assessment of NO₂ levels in the atmosphere is required for developing effective strategies for control of air pollution and improvement of air quality. Consequently, spatial NO₂ monitoring has become an important aspect of air quality assessment. Present NO₂ monitoring networks are mostly confined to urban areas, having a limited number of monitoring sites. Wide spatial NO₂ monitoring in India is constrained because of the limited availability of the monitoring equipment, such as continuous chemiluminesence monitors, high volume and handy samplers, which are expensive and need to be imported. Moreover, they require elaborate infrastructure, scientific personnel, technical support and uninterrupted power supply. In an effort to overcome the above shortcomings, passive samplers have been successfully used for large scale monitoring of NO₂ in the ambient environment.In recent years, passive samplers have been gaining increasing attention because they are simple, lightweight and cheap devices, which operate without any power source. Passive samplers have been found to be efficient, cost effective and free from the need for elaborate calibration and maintenance. Hence, they are ideally suited for developing a wide spatial network for NO₂ monitoring. This paper presents a comprehensive review including, historical development and critical assessment of validation studies along with comparison of both badge and tube type passive samplers. An attempt has been also made to highlight advantages and limitations, as well as discussion on the factors affecting the efficiency of passive samplers under field conditions.     

Effect of linear alkyl benzene sulphonate on erythrocyte sedimentation rate of teleost fish,Heteropneustes fossilis

ESR increased at all concentrations and exposures to LAS. However, increases were more pronounced at LC50 for 24 h and minimum at the end of 96 h.     

Post natal antioxidant enzyme activity of rat brain regions during developmental lead exposure

This study reports the effects of low level developmental Pb exposure on specific brain regions like hippocampus, cerebellum and cerebral hemispheres of antioxidant enzyme activities. Wistar dams were exposed to 50 ppm, 100 ppm and 500 ppm of Pb acetate in drinking water during pregnancy and lactation (gestation day 6 through PND 21 (post natal day) and activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and glutathione reductase (GR) were determined in the hippocampus, cerebellum and cerebral hemispheres of pups during treatment period (PND 7, 14, and 21 days) and also during withdrawl period (PND 35, 45, 60 and 90 days). During treatment period, SOD activity significantly (p < 0.05) decreased in all regions of all the treated groups with maximum decrease in 500 ppm treated group of 21 days, while GSH-Px and GR activities increased with maximum increase in 21 days aged 500 ppm group. During withdrawl period, the activities of all enzymes were significantly (p < 0.05) reversed. Thus the perinatal exposure of dams to variable dosages of low level lead results in characteristic neurochemical alterations in rat brain regions due to impaired antioxidants function.     

Endosulfan induced changes in phospholipids in the freshwater female catfish, Heteropneustes fossilis (Bloch)

The catfish, H. fossilis were exposed to endosulfan for 30 days at sub-lethal concentration (0.002 ppm) during different phases of its annual reproductive cycle. Its impact on total (TP) and different phospholipids- phosphatidylcholine (PC), phosphatidylserine (PS), phosphatdylinositol (Pl) and phosphatidylethanolamine (PE) were measured in liver plasma and ovary. On pesticide exposure, during preparatory phase, the hepatic TP PC and PE were declined. The plasma levels of TP, PC and PS were declined with the elevation of PE whereas in ovary only PC was lowered after endosulfan exposure. During pre-spawning phase, the hepatic TP, PC and PE declined in liver plasma and ovary after endosulfan exposure. During spawning phase, only plasma and ovarian phospholipids showed decrease in their levels following endosulfan exposure. In the post-spawning phase, endosulfan elevated the levels of TP, PC and PS in ovary but had no effect on their levels in liver and plasma. During resting phase, the TP, PC and Pl were found to be decreasing its levels. Thus it appears that this pesticide interfere with phospholipids metabolism during annual reproductive cycle of this species.     

Current understanding of the influence of environmental factors on SARS-CoV-2 transmission,persistence, and infectivity

Environmental Science and Pollution Research - Coronavirus disease 2019 (COVID-19) has emerged as a significant public health emergency in recent times. It is a respiratory illness caused by the...     

Roadmap to sustainable carbon-neutral energy and environment: can we cross the barrier of biomass productivity?

Environmental Science and Pollution Research - The total number of inhabitants on the Earth is estimated to cross a record number of 9 × 103 million by 2050 that present a unique challenge to...     

Green synthesis, characterization and antimicrobial activity of silver nanoparticles using methanolic root extracts of Diospyros sylvatica

The current research study focuses to formulate the biosynthesized silver nanoparticles for the first time from silver acetate using methanolic root extracts of Diospyros sylvatica, a member of family Ebenaceae. TEM analysis revealed the average diameter of Ag NPs around 8 nm which is in good agreement with the average crystallite size (10 nm) calculated from X-ray Diffraction (XRD) analysis. Further the study has been extended to the antimicrobial activity against test pathogenic Gram (+) ve, Gram (−) ve bacterial and fungal strains. The bioinspired Ag-NP showed promising activity against all the tested bacterial strains and the activity was enhanced with increased dosage levels.