Autism Cases on the Rise
Study Shows Increase Is Real, Not Just Due to Changes in Diagnosis Criteria
"Time is passing and science has a lot to do to find the real causes of autism," she says. "A lot has changed in the environment over the last 10 to 15 years. And I paint with a broad brush when I say environment: These changes include things like medications people take and assisted reproduction technology as well as what is in soaps and pet shampoos and toothpaste and so forth."
Autism expert Michael L. Cuccaro, PhD, associate professor of human genetics at the University of Miami, praises Hertz-Picciotto's systematic study of the rise in autism cases. He agrees with her that it's time to consider environmental factors as part of the cause of autism.
"I don't think it is premature to look for environmental risks," Cuccaro tells WebMD. "There are environmental risk factors that give rise to a wide range of developmental conditions, and there's no reason to think autism isn't one of them. And papers like this are critical to get to this point. Because you have to convince people it is not explained by all these other factors."
Environmental studies are already under way -- and research organizations are eager to fund them, Goldstein says. But the difficulty goes far beyond funding.
"We only have 20,000 to 25,000 genes. But we have a hundred thousand environmental exposures. How do you control for that?" he says. "And your genes stay the same, while environmental exposures may have come and gone. It is difficult to do these studies -- the problem is not that it isn't thought to be important."
The Hertz-Picciotto study appears in the January issue of Epidemiology. The study is co-authored by Lora Delwiche.