Potential Link Found Between Pollution and Autism in Boys

 

Although the specific culprit toxins remain unknown, environmental pollution may affect your child’s wellness with a higher risk of autism. This is according to a new, large study from the US, reported March 13th in the journal PLoS Computational Biology, which found a link between rates of genital birth defects and autism rates.

 

According to environmental wellness expert Amy Norton, ‘Researchers analysed medical records and found a correlation between U.S. counties’ autism rates and their rates of genital birth defects in boys, which could be a sign of some common environmental contributors. However, the findings, which were do not prove that any particular environmental exposure directly raises the risk for the developmental disorder. Alycia Halladay, senior director of environmental and clinical sciences for the advocacy group Autism Speaks, who was not involved in the research, argues there’s no ‘smoking gun. This study was not designed to figure out what the [environmental] factors are.’

 

That said, Norton points out, ‘Experts believe autism arises from a combination of genetic vulnerability and any number of environmental exposures. Some suspects include infections such as flu during pregnancy, certain prescription drugs taken during pregnancy and environmental toxins.’ And Halladay concurs that these latest findings support the ‘scientific agreement that it’s a mix of genes and environment.’ Hence, the lead researcher on the study Andrey Rzhetsky, a professor of genetic medicine at the University of Chicago, concluded, ‘Both genes and environment are important,’ adding that the task ahead is to figure out which environmental exposures matter.

 

‘Autism refers to a collection of disorders, usually diagnosed during childhood, that affect language and social skills,’ Norton details. ‘For the study, Rzhetsky’s team analyzed nearly 100 million U.S. health insurance claims for a county-by-county look at rates of autism and intellectual disability. They also examined rates of genital malformations in boys — such as micropenis, undescended testicles and hypospadias (in which the urethral opening is on the underside of the penis). Those genital malformations were used as an indicator of parents’ exposure to environmental pollutants…The exact causes of those birth defects are not clear, but some studies have suggested that certain environmental toxins — including pesticides and lead — might play a role. In this study, county rates of genital birth defects ranged from none to just over 2%. Overall, the researchers found, for every 1% increase in those birth defects, the rate of autism rose by close to 300%.’

 

Moreover, a strong link existed between rates of genital defects and autism even when the researchers accounted for county demographics. However, the problem is that the reason behind this correlation remains unclear. Rzhetsky surmised that genes could play some role, as could environmental factors other than pollutants. As Halladay points out, chemicals known as endocrine disruptors — which are found in plastics, food cans and other everyday products — have been linked to genital birth defects, but researchers are yet to find a connection to autism risk. Studies have, on the other hand, found a link between high exposure to air pollution during pregnancy and an increased autism risk.

 

Halladay comments, ‘Autism Speaks has a programme that funds research on the environmental factors — including toxic exposures and nutrition during pregnancy — that might affect autism risk.’ Norton adds, ‘‘Researchers continue to look for the environmental players in autism…But chemicals in the environment are only one potential reason autism rates vary across the United States. A 2012 study from the US Centres for Disease Control and Prevention found that one in 88 US children had an autism spectrum disorder — up almost 25% from just a few years before. But the rate varied widely, from one in 47 in Utah to one in 210 in Alabama. Experts speculated that the national increase had a lot to do with better detection, and that differences in awareness and autism services might explain the regional differences.’

 

 

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