A recent article in The Toronto Star featured an interview with Dr. Jeffrey Brook, leader of research within CHILD on health and the environment, and referenced a CHILD research finding about how traffic pollution affects unborn babies at the epigenetic level.
Dr. Brook, a professor in the Dalla Lana School of Public Health of the University of Toronto, was interviewed by the Star for a 24 July 2024 article about the health hazards associated with being stuck in traffic jams. In his comments, Dr. Brook observed that young children who are exposed to traffic pollution run a higher risk of developing asthma and suffering from poor lung health. As the article goes on to say, he also noted:
“‘There’s some evidence that [traffic pollution] affects the unborn fetus,’ Brook told the Star, pointing to a recent study he helped perform that found altered DNA in the umbilical cord blood of newborns, specifically in regions related to lung development, after being exposed to traffic pollution while in the womb.”
The study referred to was published in April 2024 in Environmental Health Perspectives. In it, CHILD researchers looked at chemical modifications of the DNA in babies in the CHILD Study who were born to moms exposed to traffic pollution—and nitrogen dioxide specifically—while pregnant. The researchers found that some of these gene-level changes were still present when those babies reached one year of age, even if those babies were not exposed to traffic pollution after birth. This suggests that prenatal exposure to pollution has lasting effects on how a child’s genes work.
The researchers also found the changes seemed to be more prevalent among male children and that the changes were in locations on the DNA associated with early lung development, although any link between these changes and a higher risk of asthma was uncertain.
“We were most interested in whether these gene-level changes contributed to childhood asthma; however, the number of participants in the study for whom we had asthma diagnosis information was too small to draw meaningful conclusions,” notes lead author Samantha Lee, a PhD student in the University of Manitoba lab of CHILD researcher Dr. Meaghan Jones.
“It would be useful to replicate this study in a larger population to see more clearly if there is a strong link between asthma risk and the DNA changes caused by traffic pollution.”
“The longitudinal design of the CHILD study, where we follow its participants over time, provides a major advantage for investigating persistent epigenetic changes,” adds Dr. Jones, senior author on the paper. “The study’s design allows us to track those changes within the same group of individuals through the first year of life and beyond. For this, we owe a big thanks to the CHILD families for their dedication and commitment to advancing health research.”
Returning to the article in the Toronto Star, when it comes to minimizing your exposure to pollution while trapped in traffic—including if you are pregnant and want to protect the DNA of your unborn child—Dr. Brook had some advice: use your vehicle’s air-recirculation feature with the air conditioning on, as this can help insulate you from the outside air.
Read the Star article: “Sitting in traffic is eroding your health. Here’s what drivers can do.”
The Toronto Star is Canada’s largest daily newspaper.epigenetic