Pollution and Asthma Risk in Children Starts in the Womb

New research finds that childhood asthma, before age five, begins in the womb during fetal development. Cincinnati researchers have discovered that maternal exposure to pollution can alter gene expression during fetal development, increasing the risk of asthma in children.

The new study from the University of Cincinnati (UC) and Columbia University Mailman School of Public Health appears Feb. 16 2009 in PLoS ONE. Alteration in the gene ACSL3, from maternal exposure to pollution, is now found to occur in the womb during fetal development, perhaps in response to PAH (polycyclic aromatic hydrocarbon) exposure. PAH is a a byproduct of incomplete combustion.

Researchers analyzed blood taken from the umbilical cords of 56 infants born in areas of high traffic. Both mother and child were residents in Northern Manhattan and the South Bronx. During pregnancy, the mothers were outfitted with backpacks to measure exposure to PAH that might lead to childhood asthma during fetal development in the womb.

The scientists evaluated the incidence of reported childhood asthma, comparing blood analysis with changes in the ACSL3 gene. They found a significant association between changes in ACSL3 methylation abd maternal exposure to pollution. ACSL3 is a gene associated with lung development.

Rachel Miller, MD, director of the asthma study says, “Understanding early predictors of asthma is an important area of investigation because they represent potential clinical targets for intervention.”

The study was launched by the Columbia Center for Children’s Environmental Health in 1998, as part of an effort to measure the effect of common pollutants and maternal and child health.

The study is the first to show that pollution increases the risk of childhood asthma during fetal development in the womb.