Residential pesticide use is widespread in the U.S. However, little is known about pesticide exposures among minority women during pregnancy. We have measured levels of 9 contemporary-use pesticides in 48-hour personal air samples collected during the 3rd trimester and blood samples (maternal and umbilical cord) collected at delivery from 194 African American and Dominican mothers and newborns in New York City. Our prior data show widespread prenatal pesticide use among this minority cohort. The organophosphates diazinon and chlorpyrifos and the carbamate propoxur were detected in 100% of the air samples (range 0.7-6010 ng/m3) and 57%-97% of blood samples (range 0.3-63 pg/g). Blood and air levels were not correlated. Maternal and newborn blood levels were similar and significantly correlated. The remaining pesticides were detected less frequently in air and blood. Results show that prenatal exposure is widespread and that the pesticides are readily transferred from mother to the fetus during pregnancy.