Exposure to heavy metals released to the environment through breastfeeding: A probabilistic risk estimation

Abstract Toxic heavy metals released into the environment through various anthropogenic activities, raising concerns over their potential adverse effects on human health and the environment. Biological monitoring studies are of great value in toxicological research for estimation of such health effects. The aim of this study was to evaluate the concentrations of lead (Pb), arsenic (As), and chromium (Cr) in the breast milk of urban mothers in Hamadan city, Iran and the accompanying health risk to infants. A total of 100 lactating mothers were recruited from public health care centers in Hamadan city and breast milk samples were collected at 2, 6, 8, and 12 months postpartum. Inductively coupled plasma mass spectroscopy (ICP-MS) has been used to measure target heavy metal concentrations. The median breast milk concentrations of Pb, As, and Cr were 41.90, 0.50, and 3.95 μg/L, respectively. The highest levels of Pb were observed after two months of delivery (with the mean of 96.69 μg/L and median of 45.70 μg/L). Up to 94% of the breast milk samples exceeded the WHO limit suggested for lead contamination of breast milk (