The incidence of autism has increased by 57 percent between 2002 and 2007, according to the Centers for Disease Control. Several recent studies have shown that environmental pollution is tied to that increase. The newest one, to be published in Environmental Health Perspectives, reports that mothers living close to highly trafficked freeways are twice as likely to give birth to autistic babies than mothers who do not.
The group studied children between the ages of two and five years, living in Los Angeles, San Francisco, and Sacramento, a total of 563 subjects, 259 children who were developing normally, and 304 children with autism. All of the children received developmental assessment tests and each family was interviewed personally, focusing on where the mother lived during pregnancy and her residential distance from a major thoroughfare.
Pregnant mothers living near busy highways have a greater risk of an autistic baby.: image via americancity.org
After controlling for mothers' ethnicity, education, age, and exposure to tobacco smoke, there were still 10 percent of the children who had twice the risk for autism than the others, and these children lived within 1,000 feet of a freeway.
Ongoing research, such as that being conducted by the Columbia Center for Children's Environmental Health, has already shown a high relationship between exposure to environmental pollution and developmental disabilities, such as autism, as well as an overall negative effect on IQ levels.
Environmental Health Perspectives, LA Times, via U.S. News