The cause of autism remains a mystery but there is no shortage of theories as to the possible causes. Over the past two decades, almost everything underneath the sun has been blamed as a cause of autism.

Now scientists have come back full circle and claim that perhaps it is the environment. The latest study from Children’s Hospital in Los Angeles indicates that children who live near freeways at birth have twice the risk of autism compared to children born in rural areas.

This study from L.A. found that babies who lived within 1,000 feet of a freeway were at a higher risk for autism. And this, they said, could be due to high levels of pollutants in the freeways. The study observed that more than 50 percent of autistic children were born near areas of contaminated air.

So what does this all mean?

Autism also occurs in children born to mothers who live in rural areas. Therefore, the results of this study appear puzzling. Moreover, not a single study has ever shown that autistic children have high levels of any specific chemical, metal or any types of toxic gas in their body. For now, this is just an academic study.

Even if the connection between pollution and autism was true, parents who want to prevent autism have little choice -- there are not many places in America where there are no highways or pollution. There are many other cities in the world that have worse pollution than Los Angeles -- like Beijing, Bangkok, Jakarta, Dacca or Mexico City. Yet the incidence of autism there does not appear to be any higher than anywhere else in the world. So for now, mothers-to-be who live in urban areas should relax and stop reading too much into these studies.

Reference:
http://scienceblog.com/41215/researcher-finds-proximity-to-freeway-associated-with-autism/