Heavy Metal Levels in Maternal Blood and Breast Milk and Associated Risk Factors

Objectives This study aimed to determine the concentrations of selected toxic metals in maternal blood and colostrum and to investigate their associations with environmental, lifestyle, and obstetric factors in postpartum women. Methods In this prospective observational study, 95 postpartum women who had delivered at term without any chronic or pregnancy-related comorbidities were included. Venous blood samples were collected from the antecubital vein, and approximately five to ten milliliters of colostrum were obtained from both breasts following breastfeeding within forty-eight hours after delivery. Maternal demographic characteristics, environmental exposures, supplement use, and neonatal outcomes were recorded using structured questionnaires. Metal concentrations were measured using atomic absorption spectrometry. Results Nickel concentrations were significantly higher in the blood of participants who used stoves for home heating, while cadmium levels were elevated in those consuming spring or tap water (p < 0.05). Participants residing in metropolitan areas had significantly lower iron levels in blood compared to those in rural areas (p < 0.05). Women with hemoglobin levels below eleven grams per deciliter showed elevated nickel levels in blood. Blood concentrations of nickel and cobalt were significantly lower among women who used fish oil or vitamin supplements, respectively (p < 0.05). A significant inverse correlation was observed between blood levels of nickel, cobalt, manganese, and lead and iron concentrations in colostrum (p < 0.05). In addition, iron concentrations in colostrum were significantly lower in neonates with a 1-minute Apgar score of <= 7 compared to those with higher scores (p = 0.008). Conclusion Environmental exposures and maternal nutritional status significantly influence metal concentrations in blood and colostrum. In particular, iron deficiency and suboptimal perinatal outcomes may increase susceptibility to heavy metal accumulation, underscoring the importance of comprehensive prenatal care and environmental risk assessment during pregnancy.