Excessive Exposure to Air Pollution Increases Risk of Autism, Schizophrenia

Excessive air pollution continues to plague urban areas throughout the world. Now a new study, published in the journal Environmental Health Perspectives, shows that besides certain respiratory illnesses, it can also increase the risk of autism and even schizophrenia in some individuals.

Lead study author Deborah Cory-Slechta, Ph.D., professor of Environmental Medicine at the University of Rochester, conducted three sets of experiments on mice to determine how they would react to air pollution with regards to increased risk of autism and schizophrenia. In each experiment, the mice were exposed to varying levels of air pollution that were comparable to the levels emitted during rush hour in mid-sized U.S. cities. First, the mice were exposed two weeks following birth for four hours in two four-day sections.

Researchers found that the mice carried inflammation throughout the brain--specifically the lateral ventricles that contain cerebrospinal fluid, triple their normal size. The mice, who were examined 40 and 270 days after exposure, still experienced permanent damage no matter the time frame. The mice also showed signs of increased levels of glutamate, a neurotransmitter tied to autism and schizophrenia in humans.

"When we looked closely at the ventricles, we could see that the white matter that normally surrounds them hadn't fully developed," said Cory-Slechta, in a news release. "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."

Researchers found that male mice showed higher signs of more noticeable effects from the air pollution through lower scores on short-term memory tests and poorer learning capabilities, overall.

"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."