A NIOSH study of the collection and dissolution efficiencies of heavy metal aerosols is reviewed. Purposes and components of the study, together with the general approach taken, are outlined. The filter loading and sample systems are illustrated. Dissolution and recovery studies for lead (7439921) (Pb), platinum (7440064) (Pt), tellurium (13494809) (Te), and selenium (7782492) (Se), collection efficiency test results, and aerosal concentration values are tabulated. Dissolution and measurement studies for species of Pb, Pt, Te, and Se are discussed together with aerosal generation and test results. The authors conclude that the NIOSH procedure for lead-oxide (1309600) is unsuitable using only nitric-acid, but a combination of nitric-acid and hydrogen-peroxide is suitable for all Pb species. The procedure for Te recovery is adequate. Digestion of Se by aqua-regia is necessary for the more insoluble forms. Platinum-oxide (12035824) must be heated to more than 380 degrees C. Aqua-regia is suitable for digestion of Pt, but the NIOSH standard method using nitric-acid and perchloric-acid is unsuitable.
NIOSH, U.S. Department of Health and Human Services, 100 pages, 12 references