month-old infants were supplemented with 10 mg/day of nonheme iron for up to 21 months (Burman, 1972) (i.e., no adverse effects as compared with infants supplemented with a placebo). Using a higher dose of supplemental nonheme iron (30 mg/day) for 18 months, Farquhar (1963) reported no adverse GI effects in 132 infants. Similarly, no significant adverse GI effects were reported when 124 infants 11 to 14 months of age were supplemented with 3 mg/kg body weight/day (approximately 30 mg/day) of nonheme iron for 3 months (Reeves and Yip, 1985). The median intake of iron for infants, aged 11 to 14 months, is approximately 10 mg/day. Thus, the above human data suggest that an intake of 40 mg/day would be a NOAEL for infants and young children.

Uncertainty Assessment. There is little uncertainty regarding the range of intakes that is likely to induce GI effects in infants and young children. Therefore a UF of 1 is specified.

Derivation of a UL. The NOAEL of 40 mg/day was divided by a UF of 1, resulting in a UL of 40 mg/day of supplemental nonheme iron for infants and young children. Because the safety of excess supplemental nonheme iron in children aged 4 through 18 years has not been studied, a UL of 40 mg/day is recommended for children 4 through 13 years of age, and the adult UL of 45 mg/day is recommended for adolescents.

Individuals with the following conditions are susceptible to the adverse effects of excess iron intake: hereditary hemochromatosis; chronic alcoholism, alcoholic cirrhosis, and other liver diseases;