PORTLAND — Anti-nuclear activists said Thursday that statistics collected by the state reveal a pattern of elevated cancer levels in towns downwind of Maine Yankee.

The Midcoast Health Research Group and the Committee for a Safe Energy Future said their mapping study was based on data drawn from the Maine Cancer Registry.

The study found that some of the Maine municipalities with high incidences of all types of cancers were clustered northeast of the Wiscasset plant, from Edgecomb to Union.

The anti-nuclear groups stopped short of blaming the high incidence levels on release of radioactive gases from Maine Yankee, saying additional study was needed and calling on the state Bureau of Health to undertake research.

“We should not be asked to prove harm. The industry should be forced to prove safety,” said state Rep. Maria Holt, D-Bath, speaking for the Midcoast Health Research Group.

Dr. Greg Bogdan, director of the bureau’s division of disease control, said he had not seen the mapping study but cautioned that data from the cancer registry was not designed to establish cause-and-effect relationships.

“We did a study which we reported in 1989 where we looked closely at the pattern of cancers in Lincoln County and didn’t find any pattern that would be associated with emissions from the nuclear power plant,” Bogdan said.

Maine Yankee officials dismissed the mapping study.

Leann Diehl, plant spokeswoman, said a study based on data from the National Institutes of Health shows there is no link between nuclear power plants and cancer in local populations.