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Au, Attached is the technical justification that explains the EPA’s integrated Exposure Uptake Biokinetic HEUBK} Model in general as well as the specific inputs and assumptions used to model risks for lead levels In Filnt school’s drinking water. Per our discussion yesterday, please note that the model does not include inputs specifically for the paint chip ingestion. What we can and will co is run the model using dust lead levels from a Michigan-specific study that evaluated lead concentrations in the dust inside houses of varying age. As would be expected, the cust in older homes contains more lead due to the use of lead-based paint prior to 1978. However, the effect of increasing dust-lead levels will be similar to that in the graphs illustrating the effect of increasing soil levels ecause the rnodel default assumes that the Insice dust-lead concentration is a fraction of that of soil unless more specific data are entered. wanted to share the technical justification with you ncw so that you could see the level of scientific detail represented in the modeled results. Please also rote that Michigar-specific values (e.g., air and soil concentrations} were used if available, rather than the national defaults. Or. Jennifer Gray, the HHS oxicologist with the most expertise in this model, is currently away from the office. When she returns, Dr, Gray could provide a technical briefing if you'd like. Linda xxxEND_PAGE:deq24_b181_0451_0451_1