Women exposed to industrial chemicals, including metals and pesticides during pregnancy, are more likely to have autistic children, study finds
- Researchers looked for evidence of industrial chemicals in Canadian women
- They found that metals, pesticides, PCBs and BPS chemicals were linked to autism
- They discovered the connection by looking at autistic characteristics in toddlers
Women exposed to industrial chemicals, including metals and pesticides, during pregnancy are more likely to have autistic children, according to a new study.
Researchers at Simon Fraser University measured levels of 25 chemicals in blood and urine samples from 1,861 Canadian women during the first trimester of pregnancy.
They found a direct link between increased autistic behavior in preschool-age children and exposure to certain environmental toxins during pregnancy.
The toxins that have led to autistic properties in children include metals, pesticides, polychlorinated biphenyls (PCBs), phthalates, and bisphenol-A (BPA).
The study’s authors were unable to say why the link exists or what causes it, adding that more work would be needed in the future to explore it in more detail.
Researchers at Simon Fraser University measured levels of 25 chemicals in blood and urine samples from 1,861 Canadian women during the first trimester of pregnancy (stock image)
ALMOST 2% OF THE BRITISH ARE AUTISTIC
Socially disadvantaged British children of ethnic minorities are more likely to develop autism, research shows.
According to researchers at the University of Cambridge, 1.76% of children in the UK have the autistic spectrum.
But black and Chinese students are 26% and 38% more likely to be autistic than white children, respectively, they say.
Students with a record of autism in schools were 60 percent more likely to be socially disadvantaged as well.
Autism spectrum disorder (ASD), which is characterized by impaired social communication and stereotyped behavior, affects 1-2% of children.
To understand the impact chemicals have on pregnancy and young children, the Canadian team used data from the Maternal-Infant Research on Environmental Chemicals (MIREC) Study, a pregnancy cohort from ten Canadian cities.
Study personnel recruited women during the first trimester of pregnancy between 2008 and 2011, with follow-up exams and checkups as the children got older.
“We measured the developmental outcomes of children in a convenience subsample of 600 children born to these women when they were 3-4 years old,” the team said.
When the participating children were 3-4 years old, their parents completed a preschool version of a questionnaire designed to identify autistic features.
The sum of survey responses gives a child’s T-score, with higher scores indicating greater number and intensity of ASD-like behaviors.
The researchers found that higher maternal concentrations of cadmium, lead, and some phthalates in blood or urine samples were associated with higher scores, and were especially strong in children with more autistic behaviors.
They found a direct link between increased autistic behavior in preschool-age children and exposure to certain environmentally toxic substances during pregnancy.
Authors also used the Social Responsiveness Scale (SRS) questionnaire, which provides an indication of stereotyped behavior in autistic children.
“Our results suggest that children with the most autistic behaviors, who are of greater clinical importance, appear to be particularly susceptible to these toxic substances,” the team explained.
The study’s lead author, Josh Alampi, said the work highlights “the relationship between selected environmental toxicants and elevated SRS scores.”
“Further studies are needed to fully assess the links and effects of these environmental chemicals on brain development during pregnancy,” he added.
The results were achieved using a statistical analysis tool called Bayesian Quantile Regression, which allowed researchers to determine in a more nuanced way which individual toxicants were associated with elevated SRS scores.
“The relationships we discovered between these toxicants and SRS scores would not have been discovered using a means-based method of statistical analysis (such as linear regression),” noted Alampi.
‘Although quantile regression is not often used by researchers, it can be a powerful way to analyze complex population data.’
The findings are published in the journal American Journal of Epidemiology
THE SIGNS AND SYMPTOMS OF AUTISM
According to the Centers for Disease Control and Prevention, people with autism have problems with social, emotional, and communication skills that typically develop before the age of three and persist throughout a person’s life.
Specific signs of autism include:
- Reactions to smell, taste, appearance, feel or sound are unusual
- Difficulty adapting to changes in routine
- Cannot repeat or echo what is being said to them
- Difficulty expressing desires with words or movements
- Unable to discuss their own feelings or those of others
- Difficulty with affection, such as cuddling
- Prefer to be alone and avoid eye contact
- Difficulty interacting with other people
- Cannot point or look at objects when others are pointing at them