Indicator ability of biosubstances in monitoring the moderate occupational exposure to toxic metals.

In order to improve the monitoring system, watching influence of toxic metals on human health in industrial plants, indicator properties of different biosubstances were compared. Four types of samples (whole blood, plasma, urine, and hair) from 263 workers of the "Khimprom" chemical plant (Novocheboksarsk, Russia) were subjected to multielement analysis by ICP-AES/ICP-MS. 19-25 chemical elements, including main toxic metals (Cd, Hg, Pb, etc.) were determined. The results were calculated with regard to workers' individual data on occupational exposure to chemical elements. Hair was found to be the most sensitive to toxic and conditionally toxic trace metals: Pb, Mn, Cr, Be, Ni, while occupational contact with macro elements (Na, P), trace metalloids (Si, B) and some other metals (Zn) was not reflected in hair. Whole blood relatively weakly indicated a moderate occupational level of metals except Pb and Mn, but effectively reflected deficiencies of essential elements: I, Cr, and shifts in K/Na ratio, which are likely to be secondary effects of harmful occupational factors. Blood plasma reflected only contact with Be, P; urine--only with Ni. In both whole blood and plasma the changes for the absolute majority of elements were similar. Thus, hair analysis is useful for monitoring the occupational exposure to toxic and conditionally toxic chemical elements, while a general estimation of occupational harmful influence on mineral metabolism requires simultaneous investigation of two biosubstances: hair and whole blood, or hair and blood plasma, with whole blood being more preferable. Analysis of urine is appropriate for monitoring particular chemical elements, e.g. nickel.