Maternal Exposure to Potentially Toxic Metals and Birth Weight: Preliminary Results from the DSAN-12M Birth Cohort in the Recôncavo Baiano, Brazil

Abstract

Prenatal exposure to potentially toxic metals (PTM) may impair fetal growth (FG). We investigated the relationship between maternal exposure to lead (Pb), cadmium (Cd) and manganese (Mn) and birth weight (BW) of 74 newborns. Blood was collected during the second trimester of pregnancy to determine Pb (PbB) and Cd (CdB), while hair (MnH) and toenails (MnTn) were used for Mn. Samples were analyzed by graphite furnace atomic absorption spectrophotometry (GFAAS). Sociodemographic and BW data were collected from questionnaires and maternity records, respectively. The medians (P25th–P75th) of PbB, CdB, MnH, and MnTn were, respectively, 0.9 (0.5–1.8) µg/dL; 0.54 (0.1–0.8) µg/L; 0.18 (0.1–0.4) µg/g; and 0.65 (0.37–1.22) µg/g. The means (standard deviation) of birth weight according to sex were 3067 (426.3) and 3442 (431) grams, respectively, for girls and boys. MnTn presented an inverse correlation with the BW/gestational age ratio for girls (rho = −0.478; p = 0.018), suggesting the effect of sex modification. Although BW correlation with CdB was not statistically significant, hierarchical linear regression (beta = −2.08; 95% CI–4.58 to 0.41) suggested a fetotoxic effect. These results confirmed the threat PTMs may represent and the need for more extensive research to elucidate their role in inadequate FG in developing countries.

A Cross-Sectional Analysis Investigating Pregnant Women’s Renal Function and Its Association with Lead and Cadmium Exposures—The DSAN Birth Cohort Study in Recôncavo Baiano, Brazil

“…Once the study details were discussed, a signed consent form was collected from consenting adults or the legal guardians of pregnant adolescents. Data collected from July 2019 to March 2020 and from July 2021 to September 2022 included, but were not limited to, surveys and blood specimens [ 28 , 29 ].…”

“…Detailed explanation of biological data collection and processing were previously described [ 25 , 28 ]. Briefly, a whole blood specimen was processed and analyzed by graphite furnace atomic absorption spectrophotometry (GFAAS) to determine Pb and Cd concentrations according to Menezes-Filho et al and Kummrow [ 29 , 30 ].…”