Keywords
pregnancy
breastfeeding
Mexico
How to Cite
Abstract
Pregnant and breastfeeding women constitute a population vulnerable to the toxic effects of lead, due to the transfer of this contaminant to the fetus and infant. The objective of this study was to describe the annual trends and blood lead concentrations (BLC) in a population of pregnant and breastfeeding women residing in the city of Torreón, Coahuila, Mexico. Venous BLC were quantified by atomic absorption spectrophotometry in 13,589 samples corresponding to 6,946 individuals collected between January 1, 2010, and December 31, 2024. Overall, 5.5% of pregnant women and 9.0% of breastfeeding women had BLCs above 5 μg/dL. BLC reached their lowest level between 2016 and 2017 followed by a slightly increased thereafter. Statistically significant differences were observed between groups (p<0.00001), with considerably higher BLC levels in breastfeeding women (median=2.1 μg/dL) compared with pregnant women (median=1.7 μg/dL). BLC levels increased in 57.9% of women during lactation compared to their levels during pregnancy. In conclusion, although an overall decline in BLC was observed in the environmentally exposed population, this decreasing trend has been interrupted, with BLC levels higher during lactation. Therefore, it is important to maintain epidemiological surveillance of pregnant, breastfeeding, and women of childbearing age.
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