[Biological action of different forms of lead in the rat diet]

The effects of the inclusion of biologically bound lead and PbCl2 into the diet of rats were studied. The lead dose with reference to ion was 0.65 mg/kg bw. The experiments lasted 10 days. As compared with aqueous solution of lead chloride, biologically bound lead the source of which was liver of the cattle kept on the diet supplemented with lead for a long time produced a more overt unfavourable action on porphyrin metabolism as judged from the excretion of delta-aminolevulinic acid with urine and hemoglobin level. The concentration of lead in the liver of rats fed biologically bound lead was elevated, whereas the amount of lead excreted with urine was less. No principal differences in the manifestations of lead poisoning and accumulation in organs and tissues were discovered whatever the animal group.