A COMPARATIVE-STUDY OF TRACE-ELEMENTS IN WATER FROM VARIOUS SOURCES IN SURROUNDING AREAS OF NAGPUR CITY (INDIA) BY INSTRUMENTAL NEUTRON-ACTIVATION ANALYSIS

Instrumental neutron activation analysis (INAA) has been used for the determination of 27 elements (Ag, Au, Ba, Br, Ce, Co. Cr, Cs, Eu, Fe, Ga, Hg, Hf, K, La, Mn, Na, Sb, Sc, Se, Sr, Th, P, Ta, Tb, Zn and Zr) i n 15 water samples collected from different sources (reservoirs, well, borewell, sewage tank, river, rain) in and around Nagpur city (centra l India) including doubly distilled and a sea water sample from Bombay . Sample residues after evaporation were irradiated at a thermal neutr on flux of 10(12)-10(13) n . cm(-2). s(-1) for 10 min, 1d and 1wk and counted using a HPGe detector and an 4k MCA at different intervals. Se veral environmental standards from NIST (USA), NIES (Japan) and USGS r ock were also analysed for quality assurance. Wide variations in eleme ntal concentrations have been observed in water samples from different sources. Most elemental concentrations in drinking water from various sources, are within ISI/WHO limits. Sea water showed very high concen trations of Ba, Cr, Co, Fe, Hg, Sb, Se and Zn. For doubly distilled an d rain waters, however, very low elemental concentrations of Ba, Ce, F e, Sc, Hg, Se, Sr and Th were observed.