A new study has revealed that exposure to banned chemicals could still be high, and it could be putting children at significantly greater risk for autism.
For the new study, co-author Kristen Lyall, assistant professor at the AJ Drexel Autism Institute at Drexel University in Philadelphia, PA, and colleagues set out to investigate whether prenatal exposure to organochlorines in the US could be linked to autism development – a possible association that they say has received little attention.
“Adverse effects are related to levels of exposure, not just presence or absence of detectable levels,” notes Lyall. “In our Southern California study population, we found evidence for modestly increased risk for individuals in the highest 25th percentile of exposure to some of these chemicals.”
The team identified two compounds – PCB 138/158 and PCB 153 – that appeared to have the strongest link with autism; children with the highest prenatal exposure to these PCBs were found to be at 79-82 percent greater risk of autism, compared with those with the lowest prenatal exposure.
“The results suggest that prenatal exposure to these chemicals above a certain level may influence neurodevelopment in adverse ways,” says Lyall.
Overall, the researchers say their findings indicate higher exposure to organochlorines in pregnancy may raise the risk of autism and intellectual disabilities for offspring:
“The overall pattern of our results suggests increases in risk of ASD [autism spectrum disorder] and ID [intellectual disability] with prenatal exposure to higher levels of a number of OCCs, and in particular, PCBs.
Future work should further consider genetic background in the role of these exposures on neurodevelopmental outcomes. Continued investigation of OCCs [organochlorine compounds] in association with ASD and ID is needed, given our findings and the dearth of studies investigating this topic.”
