Polycyclic aromatic hydrocarbons ( PAHs ) in coke oven emissions cause a cancer risk to humans. In a comprehensive biomonitoring study among Estonian coke oven workers, we looked at the effect of genetic polymorphisms in metabolic enzymes on urinary mutagenicity, 1 -hydroxypyrene ( 1 -OHP ) concentration in urine, and aromatic DNA adducts in white blood cells ( WBCs ). Coke oven workers were sampled twice ( samplings I and II ), and controls only once at the time of sampling I. Urinary mutagenicity was measured using the Ames test. CYP1A1, microsomal epoxide hydrolase ( mEH ), and glutathione S -transferase ( GST ) genotypes were analyzed by polymerase chain reaction ( PCR ). Urinary mutagenicity did not differ between exposed and controls, but those coke oven workers who were smokers had significantly higher ( P= 0.0002 ) mutagenic activity in urine than nonsmokers. Urinary mutagenicity was moderately correlated to levels of 1 -OHP and aromatic DNA adducts, the P values ranging from 0.0005 to 0.002. Carriers of a variant allele in exon 4 of mEH ( Arg 139 ) had elevated urinary mutagenicity ( sampling I ). In addition, urine mutagenicity of persons with predicted high mEH activity was significantly higher. Smoking habit did not explain the differences observed in urinary mutagenicity between mEH phenotype or genotype subgroups. Variation in exon 3 of mEH ( His 113 ) was related to a significantly ( P= 0.01 ) higher 1 -OHP concentration in exposed workers ( sampling II ). Workers from sampling I who had an Arg 139 variation in mEH had lower levels of adducts in lymphocytes ( P= 0.01 ) than others, while airborne benzo[ a ]pyrene ( B[ a ]P ) and His 113 variation affected interactively on adduct levels. Our study shows that a comprehensive assessment of exposure is essential for elucidation of PAH exposure at a workplace. Even at high exposures metabolic polymorphisms seem to have some effect on biomarker levels, and should be assessed in biomonitoring studies. Journal of Exposure Analysis and Environmental Epidemiology ( 2002 ) 12, 81 -91 DOI: 10.1038 / sj / jea / 7500204Keywords: aromatic DNA adducts, coke oven workers, genetic polymorphism, 1 -hydroxypyrene, urine mutagenicity.
IntroductionEpidemiological data show that exposure to polycyclic aromatic hydrocarbons (PAHs ) is possibly carcinogenic to humans and believed to be mainly responsible for an elevated lung cancer incidence among coke oven workers (International Agency for Research on Cancer (IARC ), 1983;( International Agency for Research on Cancer (IARC ), 1984 ). In addition, other carcinogens, such as aromatic amines and heterocyclic compounds, are known to be present in coke oven emissions (IARC, 1984). Recent studies reveal both high and low mean exposure levels in operating coke oven plants.Most carcinogenic chemicals, such as PAHs, need to be activated to electrophilic reactants by metabolism in vivo (Miller and Miller, 1981 ). It is known at present that many of the genes coding enzymes involved in activation and detoxification of PAHs are poly...