Air pollution is a big problem. Increased exposure to air pollution has been linked to so many health conditions, some of which Dr. Smith and I have blogged about in the past. A number of studies have come out recently about the harmful effects of air pollution on children, in particular. Children are at greater risk of exposure to toxins because they are still developing, which makes them more sensitive to toxins.

A recent study published in the journal Environmental Health Perspectives found that exposure to air pollution in utero or during early life may increase the risk of respiratory tract infections in infants. They found that exposure during the second trimester was slightly stronger than during other trimesters, suggesting the second trimester to be a time when exposure to air pollution is particularly damaging to respiratory health. Further studies of these children will help determine whether exposure to air pollution also increases asthma risk later in life.

That’s not all. Another study published in the Journal of the American Medical Association found that exposure to traffic-related air pollution during pregnancy and the first year of life is associated with more than double the risk of developing autism. “This work has broad potential public health implications,” stated Heather Volk, PhD, lead investigator of the study. “We’ve known for a long time that air pollution is bad for our lungs, and especially for children. We’re now beginning to understand how air pollution may affect the brain.” She explains that air pollution is made up of tiny particles that trigger inflammation when inhaled. “The components of these particles could be hazardous to the brain,” she stated.

Yet another recent study published in the journal Diabetologia found that levels of insulin resistance were higher in children exposed to higher amounts of air pollution. For example, proximity to the nearest major road increased insulin sensitivity in 10-year-old children by 7% every 500 metres. Whether these children go on to develop metabolic syndrome or type 2 diabetes remains to be seen (the researchers plan to do a follow-up study to track it), but this research is telling.

Toxin exposure, which certainly includes air pollution, is a major, difficult-to-control factor that is affecting our health and the health of our children. Fortunately, I have a small piece of good news—levels of air pollution are declining. What’s more, a recent study published in the journal Epidemiology has found that because of this decline, life expectancy is improving. In 545 counties throughout the country they found that air pollution levels have declined along with increases in life expectancy.

We still have a way to go, however. “Despite the fact that the US population as a whole is exposed to much lower levels of air pollution than 30 years ago—because of great strides made to reduce people’s exposure—it appears that further restrictions in air pollution levels would continue to benefit public health,” stated lead author Andrew Correia, PhD. I’m optimistic that studies like the ones I’ve reported on here will have a positive influence on the implementation of such restrictions. We obviously have a problem that is being addressed, but not quite enough.