A new study finds that prenatal exposure to rare earth elements can raise the risk of low birthweight, with some substances increasing the danger by more than three times. Researchers tracked 4,891 pregnant women who gave birth at Wuhan Maternal and Child Health Hospital between 2012 and 2014. They measured the concentration of 13 rare earth elements including cerium, ytterbium, and lanthanum in urine samples collected from the mothers. After adjusting for confounding factors such as maternal...