SKERFVING S. Chelated lead and bone lead. Scand J Work En viron Health 1992;18:113-9. In this study a close correlation [correlation coefficient (r) = 0.86, P < 0.001) was found between the blood lead level of 20 lead workers and their urinary excretion of lead for 24 h after intravenous infusion with I g of the chelating agent calcium disodium edetate, In addition , there were significant associations between lead levels in different bones (tibia /calcaneus: r=0.93, P