Maryland is suing W.L. Gore & Associates, the manufacturing giant known for its waterproof GORE-TEX lining for clothes, over claims that it knowingly polluted the air and waters around its Cecil County facilities for decades with toxic forever chemicals.

The lawsuit, filed Wednesday in U.S. District Court, calls on the Delaware-based company to pay for the state’s investigation and cleanup of widespread contamination of hazardous perfluoroalkyl and polyfluoroalkyl substances, known as PFAS, around 13 Elkton-area manufacturing facilities.

According to the state’s complaint, Gore released toxic forever chemicals into the air and water around these Cecil County facilities for decades, profiting off its products while failing to take precautionary steps to protect residents and natural areas — despite mounting and overwhelming evidence about the damaging consequences of these compounds to human health and the environment.

“It is unacceptable for any company to knowingly contaminate our drinking water with these toxins, putting Marylanders at risk of severe health conditions,” Maryland Attorney General Anthony Brown said in a statement announcing the lawsuit. “Our office will not tolerate companies that put profits ahead of the health and safety of Maryland families.”

A spokesperson for Gore denied the allegations Wednesday and said the company was surprised by the state’s escalation, particularly in light of steps it taken in the last two years to work with regulators to address contamination.

Just Wednesday morning, Gore submitted detailed testing to the state summarizing two years of groundwater investigation from its Cherry Hill facility, a step spokesperson Amy Calhoun said demonstrated the company’s proactive engagement with regulators since learning about forever chemical contamination in the groundwater near that site two years ago.

“We have been working with Maryland, employing the most current, reliable science and technology to assess the potential impact of our operations and guide our ongoing, collaborative efforts to protect the environment,” Calhoun said in a statement. “Gore has been a community partner as well as a manufacturer of products of high societal value in Maryland for decades. Our friends, families, neighbors and fellow Associates call Cecil County home and it’s important to us that we are a valued member of the community.”

The lawsuit comes as Maryland environmental regulators have been monitoring well water in the vicinity of the Gore facilities, but also as the company has provided water treatment systems to residents who use wells near some of its facilities and paid to connect some homes to a public water system, according to reporting by The Baltimore Sun.

According to the lawsuit, the company’s operations released a highly regulated kind of forever chemical known as perfluorooctanoic acid, contaminating drinking water, surface waters, soils, plants, animals and state-owned natural resources.

Because of how slowly these chemicals break down — and due to their long-lasting contamination in soil and water — PFAS have become known as “forever chemicals.” They build up in animals and in humans, and exposure to some types of forever chemicals is linked with a range of health complications, from decreased fertility, developmental effects in children, accelerated puberty, bone variations, and increased risks of obesity and cancer.

In recent years, these compounds — ubiquitous in products from food packaging and firefighting foams to shampoos and nonstick cookware — have come under heightened regulatory scrutiny at the federal level, as their health consequences have become more broadly understood.

Though the full extent of Gore’s contamination remains unclear, Maryland attorneys argue that all of the costs for investigating and cleaning up these damages should fall to Gore, not the state.

Core to the state’s arguments is its claim that Gore knew, or should have known, for decades just how harmful the chemicals going into its products could be.

Founded in 1958 by a former employee of the chemical giant DuPont and his wife, W.L. Gore has since grown into a multinational manufacturer best known for its waterproof lining for outdoors gear.

DuPont, at least, was aware that PFOA-based products could have toxic ramifications at least as early as 1961, according to a history outlined in the state lawsuit.

In the decades after DuPont issued internal warnings about the toxicity of PFOA products, according to the lawsuit, the Delaware company amassed a growing body of information on the consequences of the forever chemicals in its products. That included evidence of how the toxins get into blood and even how they could transfer from pregnant women into their unborn children.

Some of these issues were outlined at a 1984 meeting at DuPont’s headquarters in Wilmington, Delaware, where PFOA was discussed as an issue “of corporate image, and corporate liability,” according to the lawsuit.

Maryland’s attorneys contend that discussions underway within DuPont made their way to top Gore officials. One scientist present for that 1984 meeting at DuPont took a job around six years later at Gore’s Cherry Hill facility, where his role included advising on how to minimize PFOA contamination, according to the state lawsuit.

Meanwhile, evidence continued to grow about just how damaging these chemicals could be.

In 2005, DuPont reached a landmark settlement with the EPA over claims that the company had failed to disclose the toxicity of PFOA.

Officials at Gore would have known and read about this settlement, attorneys note. Still, the lawsuit says, the company failed to take steps to protect against contamination from the forever chemicals.

“Gore, through these discussions with DuPont and otherwise, knew of the potential for releases of PFOA to air and water from the Gore Facilities and yet did not inform the State,” attorneys claim in the lawsuit.

Today, elevated forever chemical contamination has been found around every Gore facility where testing has been conducted, according to the lawsuit.

Sampling around Gore’s Cherry Hill and Fair Hill facilities have turned up “exceedingly high” PFOA levels, according to the state’s lawsuit, including multiple residences with concentrations in their drinking water as high as 800 parts per trillion — or 200 times the maximum level outlined in safe drinking water regulations finalized by the EPA earlier this year. Near the company’s Appleton South site, contamination in groundwater samples has exceeded 1,000 parts per trillion.

The state’s lawsuit comes more than two years after Cecil County residents filed a class-action suit against Gore over forever chemical contamination. Residents behind that lawsuit welcomed the state’s decision Wednesday, noting that contamination is proving even more widespread than initial data suggested.

“W.L. Gore & Associates has a long history of contaminating the environment and prioritizing profit over the health of the communities in which it operates,” attorneys Philip Federico and Chase Brockstedt said in a statement. “We applaud the state of Maryland’s actions to help hold Gore accountable for this public health crisis, and on behalf of our clients, we will continue to cooperate with the State to end this contamination and obtain justice.”

The state acknowledges in its lawsuit that the company initially agreed to perform water quality tests at homes within a quarter-mile of its Cherry Hill facility, but says the Maryland Department of the Environment “was forced to bear the cost” of broadening this sampling program to a one-mile radius.

While the state appreciates Gore’s “limited investigation” into PFAS contamination around its facilities, Maryland Secretary of the Environment Serena McIlwain said in a statement, “much more needs to be done to protect the community and the health of residents.”

“We must remove these forever chemicals from our natural resources urgently, and we expect responsible parties to pay for this remediation,” McIlwain said.