A board within Pennsylvania’s Department of Environmental Protection has cleared the way for setting strict drinking-water limits for two forms of toxic man-made substances known as “forever chemicals” because they do not break down in humans and the environment.

The proposed rule approved Tuesday by the Environmental Quality Board would set stricter limits compared with a federal Environmental Protection Agency advisory for compounds within the per and polyfluoroalkyl substances, or PFAS, family. The proposal is expected to be published next year in the PA Bulletin, followed by a 60-day public comment period and five public hearings.

“This rulemaking not only protects our environment from elevated levels of contamination and pollution but also protects the public health of Pennsylvanians,” said DEP Secretary Patrick McDonnell.

The rule would set limits of 14 parts per trillion for PFOA and 18 parts per trillion for PFOS. The current EPA health advisory level is set at 70 parts per trillion for both.

Critics have attacked the EPA in recent years for failing to create hard standards for the PFAS family of compounds, offering only recommendations instead.

That has left states scrambling to create their own maximum contaminant levels. New Jersey in 2018 became the first state to set drinking-water standards for PFNA, at 13 parts per trillion, PFOA, at 14, and PFOS at 13.

Last month, the EPA pledged to take steps to regulate the toxic chemicals used in everyday products that have contaminated drinking water nationwide. Local contamination is particularly concerning in Bucks County near military bases and South Jersey near chemical plants. The Biden administration’s strategy creates enforceable standards that limit the chemicals in drinking water and designates some as hazardous substances. But the process won’t be complete until the end of 2023.

» READ MORE: Biden’s EPA plans to tackle the ‘forever chemicals’ that contaminated drinking water in Philly region and U.S.

PFAS have been used since the 1940s because they resist water, heat, and oil. They have been used to make cookware, carpets, clothing, furniture, and fabrics.

They have been associated with developmental, immune, liver, and endocrine issues. They are also associated with increases in cholesterol, liver enzymes, and uric acid levels — as well as a decreased antibody response following vaccinations. However, the risks are not fully understood.

The chemicals were widely used in firefighting foam, including on military bases in Willow Grove and Warminster. The military found residential areas near its naval air bases had high levels of PFAS in their drinking water in 2015 and 2016, including those in Bucks and Montgomery Counties, though a cleanup has since been completed.

Still, PFAS persists in the environment. In October, Pennsylvania told anglers not to eat fish caught along the Neshaminy Creek basin due to “extremely high levels” of PFOS.

Pennsylvania’s new rule would apply to all water departments, including Philadelphia’s, as well as water from non-municipal sources, including retailers and vending machines. The rule is based on water sampling, available treatment technologies, and health effects outlined by Drexel University’s PFAS Advisory Group.

Water departments would have to monitor, report, and install accepted treatment technology under the new rule.

The Delaware Riverkeeper Network, which has been critical of the time it has taken the DEP to propose a rule, called it “historic and long overdue.” The nonprofit began petitioning the DEP to make a rule four years ago and eventually sued the agency to take action.

Tracy Carluccio, the group’s deputy director, said she was pleased that the DEP was taking action but said its timeline is too long.

Larger water systems, such as Philadelphia’s, would not be required to monitor and treat for the compounds until 2024, she noted. Smaller systems serving 350 or fewer people would have until 2025. And, the rule doesn’t apply to private wells, she said, where many get their water.

“That’s way too long,” Carluccio said. “People are going to continue having to drink their water without knowing if it has PFAS in it.”

Maurice Sampson, with Clean Water Action’s Philadelphia office, called the rule a “big first step” and also accused the DEP of “dragging its feet.”

“When we start doing the testing, we’re going to see what the levels are,” Sampson said of water departments.

If they don’t meet the new rules, “all of a sudden it’s going to be a very big deal,” he said.