Markers of exposure to carcinogens: methods for human biomonitoring

Methods have been developed for the detection of exposure to carcinogens and other DNA-damaging agents in experimental animals and humans, through the detection of carcinogens or metabolic derivatives of them in body fluids or adducts bound covalently to DNA or hemoglobin. These methods are being applied in studies of exposure to environmental carcinogens, the results of which demonstrate their adequacy for detecting ambient exposures. The successful use of urinary markers of genotoxic exposures has been reported with respect to nitrosoproline as an indicator of exposure to N-nitroso compounds. The same approach has been used to detect aflatoxin B, (AFB,) metabolites and AFB,-N7-Gua as markers of exposure to aflatoxin B,. Detection of adducts formed between genotoxic agents and hemoglobin has been reported in studies of populations occupationally exposed to ethylene oxide, in which 3-hydroxyhistidine and 3-hydroxyva-line have been measured, and in smokers, whose hemoglobin has been found to contain levels of 4-aminobiphenyl and 3-hydroxyvaline that were correlated with the frequency of cigarette smoking. Albumin adducts of AFB, have been identified in exposed peopl