Erythrocyte lead-binding protein after occupational exposure. II. Influence on lead inhibition of membrane Na+,K+-adenosinetriphosphatase.

Membrane Na+,K+-adenosinetriphosphatase in erythrocytes from three groups of industrially exposed Pb workers (without toxicity, with toxicity associated with high blood Pb levels, and with toxicity associated with low blood Pb levels) was inversely correlated with Pb in the membrane fraction but not significantly correlated with total erythrocyte Pb. This difference was attributable to the proportion of erythrocyte Pb bound to hemoglobin and a Pb-binding protein of molecular weight 10,000.