A new study suggests that exposure to pesticides during pregnancy could be associated with autism in newborns.
The study, which appears in the American Journal of Epidemiology, also shows that the infants exposed to chemicals had elevated levels of autism-related genes.
A few studies have linked exposure to chemicals to increased risk of autism in children.
But this study found that exposure was a greater risk factor than previous studies had shown.
The research was conducted by researchers from the University of Minnesota Medical Center and the University at Buffalo, with support from the National Institutes of Health.
The researchers analyzed data from a large national sample of 4,569 women born in 1991 or 1992.
Their analysis included 1,636 women born between 1981 and 1993, and 4,892 women born before 1992.
The children had been born into the same household and were similar in age.
The babies were asked questions about their health, including their birth weight, gestational age and birth weight.
In addition, they were asked about their maternal exposure to chemical pesticides.
The mothers were asked whether they were pregnant and whether they had used prenatal or postnatal pesticides.
They also were asked if they had taken any medications during the past 12 months.
The birth weight was used as a measure of prenatal exposure.
In a separate study, researchers from Duke University found that prenatal exposure to certain pesticides during the first year of life was linked to the development of autism.
The team also looked at other factors including birth weight and birth length.
Both of those studies showed that the babies were more likely than other mothers to be exposed to environmental chemicals.
They didn’t find a link between exposure and autism.
But the researchers found that some chemicals had the potential to affect babies.
The chemicals used in the study were polychlorinated biphenyls, or PCBs, a type of plastic used in some plastics that has been linked to cancer.
PCBs are highly toxic and can harm unborn children.
They were found in pesticides like DEET, methyl bromide, chlorpyrifos, and DDT.
In the new study, the researchers analyzed the babies’ birth weights and prenatal exposure, looking at whether the babies exposed had higher levels of autistic genes.
The group of pregnant women were followed for four years, at which point the babies started showing autistic symptoms.
They then followed up in six years and had a baby born.
In this study, they found that the children had elevated autism-linked genes in their brains.
They found that, after the babies had developed, they had a higher risk of developing autism later in life.
The association was found even after the children were born, when the risk was highest.
The results of the study do not mean that exposure during pregnancy was the cause of autism, but they do suggest that it was a factor that could increase the risk of a child developing autism, said lead author Dr. Andrew B. Deutsch, a professor of medicine at the University Health Network, who was not involved in the research.
It’s not yet clear whether the chemicals that the researchers used were causing the babies to develop a certain type of autism risk.
The scientists plan to continue to study the babies, looking for any association with other genes.
Some studies have found that chemicals are linked to autism.
It has been known for years that some pesticides can cause autism in babies, including DDT, which was banned in the U.S. in 1973.
It is also known that some other chemicals, like PCBs and dioxins, have been linked with autism.
Deutch said there is still much work to be done to understand the role of pesticides in autism.