Blood lead, iron deficiency and IQ in Uruguayan first‐graders

Cognition in children with both iron deficiency (ID) and elevated blood lead levels (BLL) is not well studied. In 1st‐grade children (n=150, age 6.4±0.6 y, 56.7% boys) from Montevideo, Uruguay we investigated associations among BLL ≥5μg/dL, serum ferritin (SF) <12μg/L), and IQ. Mean IQ, SF and BLL were 92.9±17.0 points, 15.0±14.1 μg/L, 4.7±2.2 μg/dL, respectively. Of the study children, 48.8 and 30.2% had BLL ≥5μg/dL and ID, respectively, 13.4% had both. BLL and SF were not correlated. In unadjusted linear regressions, BLL and SF were not independently associated with IQ; neither were BLL ≥5μg/dL nor ID. However, children with both elevated BLL and ID had lower IQ 11.7 points lower than their ID‐only peers (p=0.07). Preliminary analyses suggest that elevated BLL and ID may result in particularly poor cognitive function in school children. Sponsor: NIEHS 1R21 ES16523–01