Potential health hazards from lead shielding.

Uncoated metallic lead is widely used as radiation shielding in research and development, nuclear medicine and radiology, and various manufacturing processes. The common use of lead shielding, however, may present an insidious health hazard due to lead dust. Field and laboratory measurements were collected to evaluate the distribution and removal of lead from radiation shielding material as well as to measure airborne exposures during large shielding emplacement projects. The data indicate that lead is readily dispersed from visibly oxidized as well as freshly-cleaned shielding, but that a single coating of polyurethane can reduce lead removal by nearly three orders of magnitude. Although 8-hour time-weighted average exposures for workers constructing lead shielding structures were nearly all below the Occupational Safety and Health Administration's action level of 30 micrograms/m3 (due to short work periods), the distribution of airborne lead concentrations during this kind of work demonstrates a potential for overexposure.