At a press conference in March at his Arundel dairy farm, Fred Stone talked about chemical contamination in his fields and his cows caused by sludge he had spread on the fields to help the soils. GREGORY REC/Portland Press Herald

An Arundel couple whose dairy farm is contaminated by so-called “forever chemicals” had up to 20 times the national average of PFAS in their blood, according to test results released Thursday by the farmers’ attorneys.

Fred and Laura Stone’s dairy operation has been shut down because of chemical pollution in their groundwater, soil and cows’ milk. In a lawsuit, the Stones contend their farm was contaminated by PFAS in the treated municipal sludge or paper mill ash that was applied on their crop fields as fertilizer for years.

Blood samples collected in June by the Stones’ physician and tested by a California laboratory showed that Fred Stone’s blood had levels of PFOS – one type of chemical in the larger PFAS family – of 111 parts per billion while Laura Stone tested at 93.5 parts per billion. The national average for PFAS is 4.7 parts per billion, according to the National Health and Nutrition Examination Survey.

“When the contamination was discovered at the farm, we assumed that it must have gotten inside of our bodies, because we have been drinking the water and milk for many years,” Stone said in a statement released Thursday. “These blood test results add injury to insult.  First, it was our farm, then it was our cows and now it’s us?  When will this nightmare end?”

The per- and polyfluoroalkyl chemicals collectively known as PFAS have been widely used in consumer products and industrial compounds since the 1940s. PFAS chemicals create the nonstick surfaces on Teflon and other cookware, allow jackets or carpets to repel water and are used to make paper or food packaging grease resistant. PFAS chemicals are also key ingredients in the foam used to smother flames from burning jet fuel.

But the strong chemical bonds that create those sought-after qualities in consumer products also mean PFAS linger in the environment and “bioaccumulate” in the human body. A growing number of studies have linked PFAS – particularly two phased-out varieties, PFOA and PFOS — to cancer, thyroid disruption and other health problems.

While many of the highest-profile PFAS contamination cases have occurred near military bases or factories that used the chemicals, the Stones’ Stoneridge Farm in Arundel has raised concerns about PFAS exposure from municipal sludge used as fertilizer. Many wastewater treatment facilities in Maine and across the nation distribute treated sludge, or biosolids, to farmers as a “beneficial reuse” of waste that would otherwise go into a landfill at higher cost.

The Maine Department of Environmental Protection is now requiring municipal wastewater treatment plants as well as facilities that use sludge in compost to test for several types of PFAS. Initial tests show the chemicals are present at levels above the DEP’s “screening concentration” at most facilities, thereby triggering additional testing and calculations before sludge can be applied to certain farm fields or compost can be distributed.

The Stones are suing several of the manufacturers of PFAS chemicals — including 3M and Dupont — as well as sewer districts in Kennebunk and Ogunquit. They are represented in the lawsuit by attorneys from the firm Berman & Simmons.

“Fred and Laura face a lifetime of  negative health consequences,” attorney Benjamin Gideon said in a statement. “We expected that the Stones would have elevated PFAS levels in their blood, but these numbers are shocking, particularly given that they stopped drinking the contaminated water and milk almost two years ago.”