A radiochemical solvent extraction method has been developed for the determination of Cr(III) using51Cr tracer. It is based on the complexation of Cr(III) with 8-hydroxyquinoline (oxine) and acetylacetone as mixed ligands at pH 3.8 and extraction in chloroform. Effect of various parameters such as pH, time of equilibration, nature of solvent, quantitative nature, effect of diverse ions has been studied. The method can be used up to 200 ng of Cr.
In order to assess the source of pollutants and the atmosphere quality in and around a thermal power plant, fugitive dust particulates from seven different locations and ambient air dust from six locations have been analyzed for 32 elements (As, Au, Ba, Br, Ce, Cl, Co, Cr, Cs, Cu, Eu, Fe, Ga, Hg, Hf, K, La, Lu, Mg, Mn, Na, P, Rb, Sb, Sc, Se, Ta, Tb, Te, Th, W and Yb) by employing instrumental neutron activation analysis (INAA). The method involves the irradiation of samples and comparator standards in a thermal neutron flux range of 1012–1013n·cm–2·s–1 in a nuclear reactor for 10 min and 1 day followed by high resolution -spectrometry. Wide differences have been observed in the mean elemental concentrations of Fe, Co, Br, Mn, As, P. Ba and Cu in fugitive and ambient dust particulates coliected from these different locations. Further, a comparison of the elemental contents of the dust particulates from the plant with environmental standards (Urban Particulate Matter, Coal Fly Ash, Vehicle Exhaust and Coal) show significantly lower or comparable amounts of toxic and pollutant elements in the environmental samples.
Authors:A. Garg, Vivek Singh, N. Chutke, and M. Ambulkar
In order to determine hazardous effects of smoking five different brands of Indian cigarette tobacco including its ash and smoke, three brands of bidi (a typical of Indian subcontinent) and two of chewing tobacco have been analysed for 24 elements (As, Ba, Br, Ca, Ce, Co, Cr, Cs, Cu, Eu, Fe, Hg, K, Hf, La, Na, P, Rb, Sb, –Sc, Se, Sr, Th and Zn) by instrumental neutron activation analysis (INAA). A simple and indigeneous smoking device has been developed. A mean ash content of 16.5±1.1% was obtained for different brands of cigarettes whereas smoke content was found to be 4.8±0.8%. It is observed that most elements are retained in ash and a few are transferred to smoke. Percent amount of elements retained in ash and transferred to smoke condensate have been calculated. Significant amounts of Sb, Hg, Co, Se and Zn are transferred to smoke but >90% of Ca, Fe, Sr and Cr are retained in ash. A comparison of elemental contents with the cigarette tobacco from other countries shows comparable amounts for most elements except few minor variations attributable to local soil characteristics. Most elemental contents in bidi and chewing tobacco are comparable except Br, Cr, Na, Se and Sr which are higher in chewing tobacco but its Ca content is lower. Standard Reference Materials Bowen's Kale, Kentucky Reference Cigarette and Citrus Leaves (SRM 1572) along with a newly developed tobacco CRM OTL-1 from Poland were also analysed.
Authors:A. Garg, N. Chutke, M. Ambulkar, and A. Aggarwal
The process of urbanization and industrialization during las two decades has resulted in increased level of air pollution causing hazards to human health. Instrumental neutron activation analysis (INAA) using short and long term irradiation has been employed for the determination of more than 30 elements in suspended particulate matter (SPM) from six metropolitan cities and three industrial surroundings. A comparison of mean elemental contents in dust particulates from commercial, industrial and residential zones of Delhi, Calcutta, Madras, Cochin, Bombay and Nagpur cities has shown wide variation in toxic pollutant (As, Br, Cr, Cu, Hg and Sb) concentrations. Coastal areas have shown higher concentrations of Na, K, Cl and Br. Highly industrialized Bombay showed highest levels of Br, Cl, Cr, Fe, Mg, P, Rb and Sc. Mean elemental contents in fugitive and ambient dust of a cement factory and thermal power station (both in central India) are widely different. SPM levels in fugitive dust of the two industrial surroundings are higher by an order of magnitude compared to ambient air. Analysis of ambient air dust from a paper mill showed highest concentrations of Hg, Sb and Zn. Elemental data have been compared with those of Urban Particulate Matter (SRM 1648), Coal Fly Ash (SRM 1633a) and Vehicle Exhaust Particulate (NIES No. 8) which were analysed for quality control. An attempt has been made to attribute the elemental contents to possible sources of origin.
Authors:N. Chutke, M. Ambulkar, R. Weginwar, and A. Garg
A radiochemical solvent extraction procedure has been developed for the determination of As(III) using76As tracer. It is based on the complexation of As(III) with toluene-3,4-dithiol (TDT) at pH 2 and subsequent extraction in benzene. The effect of various parameters such as pH, time of equilibration, nature of solvent, quantitative character and interferences have been studied. The method has been further developed into substoichiometric isotope dilution analysis for the determination of As at < 1 g level and employed for the analysis of several environmental and biological standard Reference Materials from NIST (USA), IAEA (Vienna) and NIES (Japan).