Assessment for Subclinical Kidney Damage in Workers Exposed to Low Concentrations of Hydrocarbons.

It has been suggested the risk of hydrocarbon-induced chronic nephropathy is negligible at low exposure levels. The first purpose of the study was to test this hypothesis by selecting a population slightly exposed to hydrocarbons. Moreover, as hypertension might be associated with an increased excretion of nephrotoxic mercapturates, the association between blood pressure and urinary concentration of S-phenylmercapturic acid (S-PMA) was also examined. Lifetime exposure assessment, main tests of subclinical kidney damage, and statistical approach were taken from a previous study that had included primarily moderately or heavily exposed workers and had found hydrocarbon-induced nephrotoxic effects. No nephrotoxic effect of exposure could be ascertained in the present study. S-PMA concentration was not increased in hypertensive workers. Thus, the risk of hydrocarbon-induced chronic nephropathy might be extremely low in workers slightly exposed to hydrocarbons. The negative results of some studies might be due to the low lifetime hydrocarbon exposures of the study populations.