The implications for risk assessment of measuring the relative contribution to exposure from occupation, environment and lifestyle: Hemoglobin adducts from amino- and nitro-arenes

Recent progress in biomonitoring allows measurement of internal exposure of individuals ranging from occupational and life style exposures to environmental levels. Ten specific hemoglobin adducts generated by polycyclic and monocyclic nitro-arenes were measured in coke oven workers and residents living on ground contaminated with explosive wastes, respectively. Consistently, adducts were found in most 'exposed' as well as control individuals, interindividual variation being great. Adduct levels in the majority of exposed individuals were within the range of reference values (95 percentile). Although hemoglobin adduct levels do not directly reflect genotoxic potential and potency of the parent compounds, they correlate with the biologically active dose. On the basis of such target doses, the contribution of specific exposures relative to 'background' and to related chemicals can be assessed. The impact of 'relative risk' on risk perception and risk management is to provide a rationale for the application of the ALARA principle (As Low As Reasonably Achievable).