Junfeng “Jim” Zhang, professor of global and environmental health, received a $2 million grant from the National Institute of Environmental Health Sciences to lead a four-year study on the effects of early life and prenatal exposure to air pollution on birth-weight and growth.

Childhood obesity increases the risk of many chronic diseases later in life. Though many factors that influence obesity, such as genetics, are well documented, scientists are beginning to explore the role that exposure to air pollution may also play – during infancy, in the womb or even before conception.

“Despite the fact that 92% of the world population today lives in places where poor air quality exceeds healthy limits, no published studies have tested the possible critical time periods, including before conception, when air pollution may impact birth weight and child growth,” Zhang said.

By analyzing vital statistics from the first two years of life for 20,000 newborns in Shanghai, the team will model where and when children have been exposed to air pollution. They’ll also test the effects of factors such as family wealth, mothers’ diet during pregnancy and parents’ smoking habits on birthweight and obesity.

“This could provide the first evidence supporting the idea that parental exposure to air pollution during critical time windows, including before conception and during the pregnancy, can be a risk factor for low birth weight and excessive growth in childhood. That information would be critical for promoting strategies to reduce children’s exposure to air pollution,” Zhang said.

Zhang holds faculty appointments at the Nicholas School of the Environment, the Duke Global Health Institute and Duke Kunshan University in China.

He is conducting the new study with colleagues from Duke, the University of Southern California, Children’s Hospital of Fudan University and the Chinese Research Academy of Environmental Science.