Could there be a link between environmental toxins and autism?
A new study by the University of Southern California suggests a correlation, if not a cause.
Children who were exposed to the highest levels of traffic-related air pollution during gestation and early infancy were found to be three times more likely to be diagnosed with the disorder.
Researchers studied more than 500 children, about half of whom were considered to be normally developing and half of whom were diagnosed with autism. The study, published Monday in the Archives of General Psychiatry, found that early exposure to high levels of traffic-generated air pollution, particulate matter and nitrogen dioxide was linked to an increased likelihood of autism.
"We're not saying traffic pollution causes autism, but it may be a risk factor for it," Heather Volk, an assistant professor at the Keck School of Medicine of the University of Southern California in Los Angeles, told Reuters.
Autism - a complex series of disorders that ranges from a profound inability to communicate and mental retardation to milder symptoms seen in Asperger's Syndrome - has become more commonly diagnosed over the past few years. It's estimated that the disorder now affects one in every 88 children born in the United States.
The researchers said certain pollutants could play a role in brain development, but that doesn't prove that being exposed to air pollution makes children autistic. While this study seems to confirm recent research linking pollutants to higher autism rates, more research is needed, experts agree.
Do you live in a high-pollution environment? What do you make of this study's findings?