Six-month-old brook trout that will stock area lakes and ponds in Washington County. Credit: Linda Coan O'Kresik

More Maine freshwater fish are considered unsafe to eat after the state’s public health agency lowered what it considers the safe level of “forever chemicals” people can ingest through fish.

The Maine Center for Disease Control and Prevention issued a new scientific brief Thursday that effectively reduces what is considered a safe-to-eat level for PFOS, which is one type of the larger class of chemicals known as PFAS, or forever chemicals.

The scientific brief cut the safety threshold for those chemicals in fish to 3.5 parts PFOS per billion parts fish from the previous level of 34.

The new threshold is the state’s latest action as it comes to grips with the extent of contamination from forever chemicals that manufacturers have used in everyday products for decades.

It follows years of testing of fish that have shown several species in state waterways with elevated contamination levels. That testing has also revealed a handful of hotspots for contamination in the state, such as Fairfield — where state officials last fall told hunters not to eat deer — and the former Loring Air Force Base in Aroostook County.

State wildlife and health officials were considering changes to the safety threshold for forever chemicals after Massachusetts lowered its safe-to-eat level late last year.

The Maine CDC based its new safety threshold on information from the federal Agency for Toxic Substances and Disease Registry that showed contamination levels previously thought to be safe are too high for humans. PFAS have been connected with several health effects, including an elevated risk of kidney and testicular cancer and small decreases in infant birth weight.

With the lower safety threshold in place, the Maine CDC issued new consumption advisories for bodies of water in eight towns and cities where fish tested had elevated PFOS concentrations.

In Fairfield, the agency issued a “do not eat” advisory for fish that come from the Police Athletic League (PAL) Ponds or Fish Brook, including any tributaries from the headwaters to the confluence with Messalonskee Stream should not be eaten.

Elsewhere in the state, the agency is recommending that people eat only a handful of fish meals per year from water bodies in Oakland, Waterville, Limestone, Sanford, Westbrook and Unity. View a complete list of the water bodies and consumption recommendations here.

Anglers can still catch fish in these bodies of water but should heed the consumption advisories, according to Maine CDC spokesperson Robert Long.

The state issued the location-specific advisories after the Maine Department of Environmental Protection tested fish from these particular water bodies for PFAS. The locations were selected because of their proximity to historical PFAS contamination in groundwater, surface water and soil, according to Long.

The Department of Environmental Protection has tested a variety of fish in waters across Maine over the last seven years. In 2019, for example, smallmouth bass from parts of the Androscoggin River had some of the highest levels of contamination in fish tested that year.

It’s widely known that PFAS have been used in paper manufacturing, and that runoff from state-licensed landfills has tested high for PFAS contamination. In addition, wastewater treatment plants — because they receive runoff from landfills, industrial waste and sewage from homes where PFAS end up in human waste — release millions of gallons of wastewater into rivers each day that could contain elevated PFAS levels.

Sawyer Loftus is an investigative reporter at the Bangor Daily News. A graduate of the University of Vermont, Sawyer grew up in Vermont where he worked for Vermont Public Radio, The Burlington Free Press...