BIOMONITORING OF AROMATIC-AMINES-IV - USE OF HEMOGLOBIN ADDUCTS TO DEMONSTRATE THE BIOAVAILABILITY OF CLEAVAGE PRODUCTS FROM DIARYLIDE AZO PIGMENTS IN-VIVO

The release and availability of the carcinogenic component of the solu ble azo dye Direct Red 46 and the insoluble azo pigment Pigment Yellow 17 were analyzed in Wistar rats using hemoglobin adducts as a dosimet er. The levels of hemoglobin adducts were found to be very low. Intest inal cleavage and release of 3,3'-dichlorobenzidine (3,3'-DCB) from Di rect Red 46 and Pigment Yellow 17 was calculated to be 3% and 0.6% of the dose, respectively, in a 4-week feeding study. It is proposed to m easure blood samples from exposed humans in order to test the applicab ility of the method and eventually to use it for controlling human exp osure to the carcinogenic colorant components.