[Multi-indicator biochemical and clinical evaluation of occupational exposure of workers in the petrochemical industry. II. Results of the search for early clinico-biochemical signs of exposure to toxic substances present in the petrochemical industry. Analysis of the results of 5-year epidemiological studies].

The activities of GGT (EC 2.3.2.1.) and glycine transaminidase (EC 2.6.2.1.) increased in all studied groups after at minimum four years of exposure to: acetobenzene, furfurol, ethylene--derivatives, polypropylene and butadiene. Besides these universal indicators the specific ones were found for a particular group of exposure: for acetobenzene--sialic acid, haptoglobine and IgA, for furfurol--sialic acid and haptoglobine, for ethylene--derivatives--haptoglobine, ceruloplasmine and the activity of arginase of the red blood cells, for polypropylene--IgA, for butadiene--proteolytic activity. These changes are treated as a manifestation of adaptive processes--the answer of the body to the environmental stimuli but not as the signs of early damage. The need of verification of the results by prospective studies is stressed.