Introduction: Methylmercury (MeHg) is a neurotoxin that crosses the blood-brain barrier and the placenta and causes harm to the fetus. It has been reported that in children causes mental retardation, decreased IQ, memory loss, behavioral disorders, among others. These effects are particularly important in infants because they may be irreversible. The objective was to estimate IQ loss, mild mental retardation in infants, and disability adjusted life years (DALYs) in infants from exposure to methylmercury estimated from mercury levels in hair of women of childbearing age. Methodology: cross sectional study. For estimates, the "mercury spreadsheet" tool developed by Poulin and Gibb (1) from mercury levels in hair of women of childbearing potential participants in a study conducted in 2013 in Bogotá was used. Results: It was found that 97.5% infants lost 0.18 IQ points and 2.5% lost 0.54 points. The incidence of mild mental retardation was estimated as 0.54 per 1,000 infants, and also a loss of 6.5 DALYs per 1,000 newborns, for a total of 662 lost years. Conclusions: Children from Bogotá are exposed to MeHg, which can cause a loss of IQ, DALYs and mental retardation. This should raise the need to implement control actions to avoid and decrease the exposure to mercury in women of childbearing age and pregnant women, in order to avoide damage associated with babies exposure to MeHg. 1. Poulin J, Gibb H. Mercurio, Evaluación de la carga de morbilidad ambiental a nivel nacional y local. OMS. 2008;16: 1-75.