Exposure to air pollution early in life produces harmful changes in the brains of mice, including an area of the brain associated with autism and schizophrenia in humans. The mice also were compromised in areas of short-term memory, ability to learn, and impulsivity.
Another confirmation that air pollution affects the brain
The findings aren’t new and are consistent with other studies showing similar associations. “Our findings add to the growing body of evidence that air pollution may play a role in autism, as well as in other neurodevelopmental disorders,” noted Deborah Cory-Slechta, PhD, professor of Environmental Medicine at the University of Rochester.
Three experiments dramatically confirm it
Three different experiments exposed mice to the typical levels of air pollution found in a moderately sized US city during rush hour. They started the exposure when the mice were two weeks old during one of the most critical times of development. They were then exposed again for four hours each day for two four-day periods. Only 24 hours after the first exposure, researchers examined the brains and found rampant inflammation and the brains’ lateral ventricles were enlarged two-to-three times normal size. “When we looked closely at the ventricles, we could see that the white matter that normally surrounds them hadn’t fully developed,” explained Cory-Slechta. “It appears that inflammation had damaged those brain cells and prevented that region of the brain from developing, and the ventricles simply expanded to fill the space.” And the damage remained during subsequent examinations showing that it was permanent.
The unregulated pollution particles may be the most dangerous
For decades, the effects of air pollution has focused on the lungs. Researchers are now starting to see the effects on the brain, particularly young brains still in development. Interestingly, larger particles of pollution – the ones regulated by the government – are not as dangerous to the brain. It’s the smaller particles which can move more freely through these delicate areas which cause the most concern. These ultrafine particles are not regulated by the EPA. “I think these findings are going to raise new questions about whether the current regulatory standards for air quality are sufficient to protect our children,” concluded Cory-Slechta.
Source: MedicalNewsToday, Environmental Health Perspectives