Lead-induced anemia: dose-response relationships and evidence for a threshold.
Schwartz-J; Landrigan-PJ; Baker-EL Jr.; Orenstein-WA; Lindern-IH
Am J Publ Health 1990 Feb; 80(2):165-168
Data obtained in 1974 during an epidemiologic evaluation of lead (7439921) exposure in children living near a lead smelter were reexamined to assess dose response relationships between blood lead level and hematocrit. The smelter in question was located in Kellogg, Idaho. Blood lead levels of 1.193 micromoles/liter (microm/L) and above were noted in 285 of 919 children living near the site. In 170 of the 172 children living within 1.6 kilometers of the smelter the blood lead levels were above 1.193microm/L. The highest level recorded was 7.91microm/L. A positive association was noted between the airborne concentration and the lead in the soil to the lead in the blood of these children. Data for both blood lead levels and hematocrit were available for 1,058 children. In the present evaluation, the focus was on 579 children 1 to 5 years of age. The results demonstrated a strong negative, nonlinear dose response relationship between blood lead level and hematocrit in children, strongest in the youngest children. The data strongly suggested that lead induced anemia was a biologically and clinically important consequence of lead absorption, even at low levels of exposure. The data also implied that there was no margin of safety between the threshold blood lead level at which lead begins to cause depression of hematocrit in young children and the blood lead level currently considered by the Centers for Disease Control to represent the upper limit of acceptability.
NIOSH-Author; Blood-analysis; Lead-poisoning; Environmental-contamination; Blood-cells; Hematology; Hemolytic-anemia; Lead-smelting; Epidemiology
American Journal of Public Health