EPA-McLaren/Hart-ChemRisk Joint Project to Develop a Stochastic Approach for Assessing Non-Carcinogenic Risk--A Status Report. R. E. Keenan, M. Dourson, P. S. Price, J. Swartout, and Steave Su, ChemRisk - A Division of McLaren/Hart, 1685 Congress Street, Portland, ME 04102
In February, 1994 ChemRisk and EPA entered into an agreement to jointly develop a stochastic approach for characterizing the uncertainties in establishing reference doses. Under this program ChemRisk and EPA will work together to develop a database of toxicological information which will be used to establish distributions for each of the major sources of uncertainty setting reference doses. This database will be used to quantitatively characterize the different sources of uncertainty in the reference dose setting process. In addition, the project will develop a methodology for integrating uncertainty in the reference dose with uncertainty in dose rate estimates to produce an analysis of the probability of the occurrence of non-carcinogenic effects in an exposed population. The authors will report the results of the first ten month's activity on this project, the status of the database, and preliminary conclusions on the distribution of key sources of uncertainty. In addition, the overall schedule of the project and the final deliverables for the project will be discussed.