FAIRFIELD — A federal agency is in the early stages of evaluating the public health affects of “forever chemical” contamination, in what appears to be the first time federal authorities are directly involved in investigating the contamination in Maine.

There have been conversations involving the state’s congressional delegation, but Fairfield Town Manager Michelle Flewelling said this is the first time the town is receiving federal assistance.

“The fact that any organization that wants to take the time to investigate what is going on in our community is wonderful,” Flewelling said. “Anything that can be done that helps Fairfield find a solution to what is going on with its current circumstances can’t be bad.”

The Agency for Toxic Substances and Disease Registry, or ATSDR, will begin a public health assessment in Fairfield, evaluating PFAS contamination and its impact on the health of residents, a spokesperson for the agency said in an email this week.

This is the first time the agency is in Maine specifically to investigate PFAS. It did, however, earlier conduct a consultation with the Penobscot Nation to identify possible risks of eating certain kinds of fish. That review ended up identifying PFAS in fish tissue.

PFAS, or per- and poly- fluoroalkyl substances, is a group of synthetic chemicals first created in the 1940s. The chemicals are both oil and water repellent, which makes them useful in a wide variety of consumer goods. But they do not break down in the body or the environment, earning them the nickname “forever chemicals.”

The agency will evaluate PFAS concentrations in water, soil and local food sources, such as deer and fish, as well as identify the ways people come in contact with the chemicals and determine how that exposure could impact public health, the spokesperson said. The assessment will culminate in a written report with the agency’s findings and recommendations for future action. The process will likely take more than a year to complete.

The agency investigates environmental health threats and researches related health impacts. A sister agency to the federal Centers for Disease Control & Prevention, ATSDR is part of the U.S. Department of Health and Human Services.

The agency has been researching PFAS since 2009, and has worked in more than 40 communities to assess the health impact of PFAS, including ones in Arkansas, Colorado and New York — most of which are located near military bases.

The agency has separately created a toxicological profile for perfluoroalkyls, part of the group of chemicals that are considered PFAS. It has found that those suffering particularly high levels of exposure are manufacturing workers who work with the chemicals, communities near these chemical facilities and people who use many products containing perfluoroalkyls.

That differs from the contamination in Maine, where high levels of PFAS have been found in agricultural areas. The contamination here has been linked to the spreading of sludge, a wastewater treatment byproduct, largely on farmland.

The agency has done assessments in similar settings, including in Decatur, Alabama, where it investigated PFAS in sludge that was used on agricultural fields, and in Lubbock County, Texas, on farmland near a former Air Force base.

The agency is working now with the federal Environmental Protection Agency to evaluate PFAS in nondrinking water in towns in Massachusetts and Delaware.

The Maine Department of Environmental Protection has been investigating the contamination in Fairfield and has tested numerous private wells in the area, and has found extremely high PFAS levels in several places.

Maine has a drinking water standard for PFAS of 20 parts per trillion, and any home with levels higher than that will have a carbon filtration system installed by the Maine DEP.

The Maine Department of Inland Fisheries & Wildlife has also tested animals in the area and found contamination in deer — prompting the department to issue a do-not-eat advisory for the area. Several species of fish have also been tested in locations around the state, and the department issued consumption advisories for several bodies of water.

As part of the first steps of the Fairfield assessment, the New England regional director for ATSDR, Tarah Somers, spoke to the Town Council at a meeting Wednesday.

“When we do a health consultation, what we really want to do is make it specific for that community, so that we can make sure that we understand how exposures are happening in your community,” Somers said.

Representatives from the agency also held two public sessions Thursday so that residents could discuss their experiences.