A recent study by researchers of the Columbia University published on the American Journal of Epidemiology indicates that prenatal exposure to PAHs (Polycyclic Aromatic Hydrocarbon) is associated with obesity in childhood.
The study involved African-American and Hispanic children born in the Bronx or Northern Manhattan (New York) between 1998 and 2006. Their mothers, aged from 18 to 35 years, underwent personal air monitoring for PAH exposure during pregnancy. The children were followed up to age 7 years.
After adjustment for child’s sex, age at measurement, ethnicity, and birth weight and maternal receipt of public assistance and pre pregnancy obesity, higher prenatal PAH exposures were significantly associated with higher childhood body size.
Pregnant women exposed to higher concentrations of polycyclic aromatic hydrocarbons were more than twice as likely to have children who were obese by age 7 compared with women with lower levels of exposure.
Poor diets and physical inactivity are the main culprits for obesity, but there is new evidence that air pollution can play a role. Indeed, for many people without the resources to buy healthy food or the time to exercise, prenatal exposure to air pollution make them even more susceptible to obesity.
The increased risk of obesity is another negative effect of exposure to PAHs. Other well known consequences of prenatal exposure to PAHs are a negative effect on childhood IQs and linkage to anxiety, depression and attention problems in young children. Polycyclic aromatic hydrocarbons are also known carcinogens.
It is therefore evident that exposure to PAHs must be reduced. This can be done, for example, by reducing the traffic of diesel vehicles from the city centres.
A. Rundle, L. Hoepner, A. Hassoun, S. Oberfield, G. Freyer, D. Holmes, M. Reyes, J. Quinn, D. Camann, F. Perera, R. Whyatt. Association of Childhood Obesity With Maternal Exposure to Ambient Air Polycyclic Aromatic Hydrocarbons During Pregnancy. American Journal of Epidemiology, 2012; DOI: 10.1093/aje/kwr455
Perera et al. Prenatal Airborne Polycyclic Aromatic Hydrocarbon Exposure and Child IQ at Age 5 Years. Pediatrics, August 2009; DOI: 10.1542/peds.2008-3506
Frederica P. Perera, Deliang Tang, Shuang Wang, Julia Vishnevetsky, Bingzhi Zhang, Diurka Diaz, David Camann, Virginia Rauh. Prenatal Polycyclic Aromatic Hydrocarbon (PAH) Exposure and Child Behavior at age 6-7. Environmental Health Perspectives, 2012; DOI: 10.1289/ehp.1104315