Development of a Strategy for Biological Monitoring in a Chemical Plant Producing 3,3′-Dichlorobenzidine Dihydrochloride

Abstract

In a chemical plant in Germany producing 3,3′-dichlorobenzidine dihydrochloride for the manufacture of colorants, blood and urine samples were taken for biological monitoring. 3,3′-Dichlorobenzidine (DBZ) was analyzed in urine by thin-layer chromatography and subsequently further combined with analysis of adducts of 3,3′-DBZ in hemoglobin. Data highlight current ranges of industrial exposure to 3,3′-DBZ in Germany and demonstrate the applicability of biological monitoring to minimize this exposure. Effective biological monitoring was achieved by a combination of monitoring hemoglobin adducts with spot samplings of urinary 3,3′-DBZ excretion in cases of reported exposure periods. Data presented might help to identify biological guidance values (BGV/BAR) for 3,3′-DBZ-exposed individuals.