PROVO -- A group of Utah doctors worried about the health effects of smog are pointing to a growing series of studies connecting autism to air pollution.

Several studies have been done linking the disorder to metals and other exhaust pollutants in the air, but new Harvard University research is the first nationwide study.

The results are especially startling because Utah has both one of the nation's highest autism rates and pollution levels during winter inversions.

According to the U.S. Centers for Disease Control, one in 47 Utah children is afflicted with autism, compared to one in 210 in Alabama, which has the best rate. According to the Utah Registry of Autism and Developmental Disabilities, the number of Utah 8-year-olds with autism has come close to tripling since 2002.

Dr. Brian Moench of Utah Physicians for a Healthy Environment told the Daily Herald that Utah must pay attention to the studies and take action -- or continue to see more children born autistic. The choice is stark.

The problem is that children in the womb are known to be susceptible to neurological or genetic damage when exposed to heavy metals and diesel exhaust pollutants. The Harvard study gauged 325 autistic children of nurses.

"Air pollution contains many toxicants known to affect neurological function and to have effects on the fetus," states the Harvard study.

The study showed that exposure in the womb to diesel, lead, manganese, mercury, methylene chloride and an overall measure of metals was "significantly associated with autism spectrum disorder," with the highest association from exposure to diesel exhaust.

In addition, the study showed that boys seem to be much more affected by air pollution in the womb than girls when it comes to autism.

The researchers concluded that more studies are needed, especially to see if one of the metals is more likely to be the cause of autism than another.

The data comes on top of smaller studies done in 2006, 2009, 2010 and 2011, which also pointed to a potential link between autism and air pollution.

Those studies usually focused on one state.

Children in the Harvard research were from Utah and all other states in the nation, born between 1987 and 2002, and studied to correlate pollution levels in the area where the mother lived while pregnant.

Data showed that the children who developed autism were more likely -- to a statistically significant factor -- to have been exposed to high levels of air pollution in the womb.

According to the study, several of the heavy metals are known to have the ability to mutate genes while children are in the womb.

"Further studies examining personal exposure to toxicants during gestation and concentrations of toxicants in the blood of newborns may permit the identification of specific agents that increase risk for autism spectrum disorder," state the authors. "Given results of our present study, which strongly support previous evidence of associations between air pollution exposure and autism spectrum disorder, such studies are warranted."

State officials have said that cars are by far the largest factor in Utah's air pollution. Moench said solutions include better mass transit, especially bus service, which is cheaper and more flexible. He believes fares should be subsidized to increase use.

"Everyone who will use it is doing the community a favor," he said.

The World Health Organization recently "declared air pollution a carcinogen," Moench said, "more important globally than secondhand cigarette smoke as a trigger for cancer. It is a big deal. Air pollution affects virtually every organ you have because it creates the same low-grade inflammatory response as smoking does."

Moench said both state officials and Wasatch Front residents should be taking air pollution's health consequences more seriously, especially when it comes to potentially causing autism in the womb.

"That is such a devastating outcome," he said. "Utah is unique in that. That in and of itself ought to get people and state officials to take action.

"This problem is serious and is hurting Utah's finances, health, and future. Solving air pollution requires bolder moves than we have taken in the past, and that is what the public is now beginning to demand."

-- Caleb Warnock covers 11 cities in north Utah County and is also the Daily Herald's environmental reporter. You can find him on Facebook, at or by email at
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