Chemicals banned decades ago still appear to be lingering with a new study finding a significantly higher risk for autism among children exposed to certain compounds during pregnancy.

Production of what are known as polychlorinated biphenyls, or PCBs was halted in the United States in the late 1970s. Nonetheless, researchers say such chemicals remain in the environment and can be absorbed in the fat of animals that people eat.

A study published Tuesday in the journal Environmental Health Perspectives suggests that exposure during pregnancy to the highest levels of these compounds — which were once used in items ranging from coolants to insulators and electrical products — can increase a child’s risk of autism by as much as 80 percent.

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For the study, researchers looked at 1,144 Southern California kids born between 2000 and 2003 whose mothers submitted blood samples during their pregnancies as part of a prenatal screening program.

Children with the highest levels of prenatal contact with PCBs had an increased risk of 50 to 82 percent, depending on the chemical compound, as compared to kids with no or low exposure, the study found.

Meanwhile, elevated levels of PCB exposure were also associated with an increased risk for intellectual disability without autism.

“The results suggest that prenatal exposure to these chemicals above a certain level may influence neurodevelopment in adverse ways,” said Kristen Lyall, an assistant professor at Drexel University’s A.J. Drexel Autism Institute who led the study. “We are definitely doing more research to build on this — including work examining genetics, as well as mixtures of chemicals.”