Physiologically Based Pharmacokinetic Modeling of Airborne Lead in Support of Development of an Occupational Exposure Limit for Department of Defense Workers
Abstract
The Department of Defense (DOD) commissioned the National Research Council (NRC) to assess the potential health effects associated with exposure of DOD personnel to lead (Pb) at firing ranges. In that report, NRC concluded that the current Occupational Safety and Health Administration permissible exposure limit and the blood lead levels (BLLs) on which it was based were not sufficiently protective of worker populations covered under the general industry standard. In support of future selection of an occupational exposure limit, the relationship of airborne Pb levels to BLLs is of interest to the DOD. A subset of the BLLs identified as relevant to the management of health risks of exposed workers was selected as targets for extrapolation to equivalent airborne Pb values. The existing OFlaherty physiologically based pharmacokinetic model for Pb in humans was modified to facilitate probabilistic simulations of DOD worker population BLLs, after determining parameter distributions of model inputs that were sensitive determinants of final predicted BLLs. Under working lifetime exposure, workplace airborne Pb time-weighted average concentrations of 0.80, 3.6, 6.5, or 9.7 mu g/m3 were predicted by the model to maintain BLLs below 5, 10, 15, or 20 mu g/dl, respectively, in the 95th percentile full-time Pb-exposed DOD employee.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 2019
- Accession Number
- AD1068790
Entities
People
- Lisa M. Sweeney