Patterns of blood lead levels in US black and white women of childbearing age.

While high-dose lead exposure has long been known to be detrimental to reproductive functioning, several recent studies have reported adverse effects such as shortened gestation, decreased birthweight, and increased incidence of spontaneous abortion in association with maternal blood lead levels as low as 0.48 to 0.72 mumol/L (10 to 15 micrograms/dL). Using data from the second National Health and Nutrition Examination Survey, we examined patterns of blood lead levels by age for US black and white women of childbearing age. We found that sizable percentages of women have blood lead levels that may place them at risk for poor reproductive outcomes and that disparities exist between the racially identified groups. Black women tend to have higher lead levels than white women, and the magnitude of this difference is larger among older compared to younger age-groups of reproductive-age women. This disparity may reflect the cumulative effect of differential environmental exposure to lead and may have implications for the excessive incidence of adverse reproductive outcomes currently seen in US black women.