Air Pollutants Cause Prenatal Genetic Changes

Frederica P. Perera, Dr. P.H.
Columbia University
P01ES09600, R01ES08977, R01ES11158, R01ES12468

Background: Polycyclic aromatic hydrocarbons (PAHs) are a group of over 100 different chemicals that are formed during the incomplete burning of coal, oil and gas, garbage, and almost any organic substance. PAHs can cross the placenta, and many have been shown to cause cancer in animal studies. Research has suggested that the developing fetus is susceptible to carcinogens and that in utero exposure to pollutants can cause DNA damage, chromosomal changes, and increased risk of childhood cancers such as leukemia. Other research has indicated that pediatric leukemia is initiated prior to birth. In a new study of 60 babies in New York City, NIEHS-supported researchers at Columbia University show for the first time that prenatal PAH exposure causes chromosomal changes that have been linked to leukemia and other cancers.

Advance: Using a technique known as fluorescence in situ hybridization, these researchers were able to see and count the number and types of chromosomal changes that occurred. Cultured white blood cells from umbilical cord blood were used in the study. Prenatal exposure was assessed by questionnaires and by analysis of personal air monitors worn by mothers during the third trimester of pregnancy. Exposure to airborne PAHs was significantly associated with stable chromosomal aberrations. Also interesting was the finding that African-American babies had a higher frequency of chromosomal changes than Dominicans, suggesting either other unmeasured factors or variations in susceptibility.

Implications: These findings suggest that prenatal exposures ”have the potential to cause cytogenetic damage that has been related to increased cancer risk.” Similar air pollution conditions occur in other cities in the U.S. and the world making these findings of global importance. While further research is necessary to confirm these findings and to estimate the increase in cancer risk from the exposures, these results point out the importance of protecting children from avoidable exposures.

Citation: Bocskay KA, Tang D, Ofjeula MA, Liu X, Warburton DP, Perera FP. Chromosomal aberrations in cord blood are associated with prenatal exposure to carcinogenic polycyclic aromatic hydrocarbons. Cancer Epidemiol Biomarkers Prev 2005;14(2):506-11.