Industrial exposure, carcinogen risk assessment

In order to illustrate the various possible approaches to estimating a combined potency for a multisite carcinogen, an example is offered here. The carcinogen selected, 1,3-butadiene, is an important industrial chemical and a widespread air pollutant. Risk assessments for this chemical have been published (OEHHA 1992 US EPA 2002). The more recent estimate by US EPA (2002) depends primarily on estimates of risk from the various human epidemiology studies of industrial exposures to this chemical, but it is their analysis of the animal bioassay data and also that by OEHHA (1992) which are of interest for the present purpose. 

Sivulka, D. J., and Seilkop, S. K. (2009). Reconstruction of historical exposures in the U.S. nickel alloy industry and the implications for carcinogenic hazard and risk assessments. Regul Toxicol Pharmacol 53, 174-185. 

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