Lead, mercury, and cadmium in umbilical cord serum and birth outcomes in Chinese fish consumers

• Metals exposure levels in umbilical cord serum of fish consumers were determined.
• Multivariable regression analyses showed negative effects of Pb and Hg on birth outcomes.
• Middle tertile Pb and Hg exposure levels were found significantly negative effects.

Heavy metals such as lead (Pb), mercury (Hg), and cadmium (Cd) were detected in the islands of Yangtze River estuary and Hangzhou bay and their exposure caused potential health risk for the residents. To assess the exposure levels of Pb, Hg, and Cd, the umbilical cord serum samples were collected from 103 mother-newborn pairs as the noninvasive specimens. The association of the concentration of Pb, Hg, and Cd with the birth outcomes was evaluated. Pb, Hg, and Cd had high exposure levels with the median concentrations at 76.20 μg L−1 [interquartile range (IQR): 44.71, 115.80], 21.94 μg L−1 (IQR: 15.10, 27.64), and 6.36 μg L−1 (IQR: 3.63, 13.34), respectively. A unit increase in the Pb umbilical cord serum concentration (μg L−1) was significantly associated with a 0.29 cm (95% CI: −0.50, −0.09) decrease in birth height and a 0.22 cm (95%CI: -0.44, 0.00) decrease in head circumference. The middle tertile Pb and Hg exposure levels were found significantly negative effects on birth outcomes compared with low tertile exposure levels. Exposure to Cd showed no apparent effect on birth outcomes. Our results suggested that Pb and Hg exposure has potential adverse effects on birth outcomes in Chinese fish consumers from Yangtze River outlet and Hangzhou bay estuary regions.