RESUMO
PIP: Blood lead (PbB) and serum iron (Fe-S) levels were studied in 148 nonoccupationally exposed 19-21 year old student volunteers: 57 males, 47 non-oral-contraceptive (OC)-using females and 44 regular OC-using females. PbB levels ranged from 46 to 238 parts/billion. Free-erythrocyte-porphyrins (FEPs), Fe-S, hemoglobin, hematocrit, total Fe-binding-capacity (TIBC), and unsaturated-IBC were measured. A negative correlation was seen between PbB and Fe-S in males (r = -.36, p .01). Females had a significantly higher FEP level than males at the same PbB level (p .05). OC users had significantly higher Fe-S levels (p .0005) and TIBC (p .005) than non-OC users. A 2nd group of 51 males also showed a negative trend in the relationship between PbB and Fe-S. 2 hypotheses are suggested to explain this negative relationship: 1) competition between iron and lead in regard to the metal-binding capacity of some serum proteins, and 2) feedback inhibition by heme on the iron transport through the erythrocyte precursor membrane.^ieng