Application of the zinc protoporphyrin (ZP) test as a monitor of occupational exposure to lead.

Zinc protoporphyrin, the predominant abnormal metabolite that appears in whole blood as a result of chronic lead absorption, can be assayed fluorometrically in diluted whole blood with great sensitivity. An extremely simple and rapid test for the effects of lead absorption is described that is based on this assay. Results of a field trial show a characteristic dose-response relationship between zinc protoporphyrin and lead, and indicate that this test should be seriously considered as a monitor for the effects of chronic lead adsorption.