Risk assessment for people exposed from different environments

After the identification of the hazardous intrinsic properties of a carcinogen an attempt is made to estimate, if possible, the potency of the carcinogenic effect. For the evaluation it is, furthermore, of interest to know the genotoxic properties of the chemical. The next step would be to try to estimate the potential exposure for people in different environments. This could be intake from use of it as an additive in food or occurrence as a contaminant in food, drinking water, soil or air. The air exposure might come from contaminants in the working environment, in-door air or ambient air. The outcome of the hazard and exposure assessments would not be the only factors in a risk assessment or suggested limit values. Other factors might be the political-administrative background coming from different legal systems, even in the same country, which might apply different safety ambitions. This might result in the application of different risk levels (1:1 million, 1:10 million) or different safety factors, if that approach is used for non-genotoxic animal carcinogens.