Maternal Blood Levels of Toxic and Essential Elements and Birth Outcomes in Argentina: The EMASAR Study.

Pregnant women's levels of toxic and essential minerals have been linked to birth outcomes yet have not been adequately investigated in South America. In Argentina, n = 696 maternal whole blood samples from Ushuaia ( n = 198) and Salta ( n = 498) were collected in 2011-2012 among singleton women at 36 ± 12 h postpartum and analyzed for blood concentrations of arsenic (As), cadmium (Cd), mercury (Hg), lead (Pb), copper (Cu), manganese (Mn), selenium (Se) and zinc (Zn). This study examined the associations between maternal elements levels and birth outcomes, and sociodemographic factors contributing to elements levels. Maternal age, parity, body mass index, smoking, and education were linked to concentrations of some but not all elements. In adjusted models, one ln-unit increase in Pb levels was associated with increased gestational age (0.2 weeks, 95% CI = 0.01-0.48) and decreased birth weight (-88.90 g, 95% CI = -173.69 to -4.11) and birth length (-0.46 cm, 95% CI = -0.85 to -0.08) in the Salta sample. Toxic elements concentrations were not associated with birth outcomes in Ushuaia participants. Birth outcomes are multifactorial problems, and these findings provide a foundation for understanding how the body burden of toxic and essential elements, within the socioeconomic context, may influence birth outcomes.