The report by researchers from Stockholm University and New York’s Columbia University found that children born in the eight municipalities experiencing the highest levels of radiation were 3.6 percent less likely than others to qualify for high school, the United Press International reported Thursday.

The researchers said it appears prenatal exposure to radiation levels previously considered safe was actually damaging to cognitive ability.

Radioactive fallout from the 1986 Chernobyl disaster spread as far west from Ukraine as England and traveled north though Belorussia, Russia and Scandinavia.

The journal Chemistry World said the report is expected to be published as a U.S. National Bureau of Economic Research working paper.