Bottled water has become a familiar sight in some schools in Maryland, where officials have found the drinking water tainted with lead, known to cause brain damage in children.

The bottles may begin rolling out in more schools. This time the culprit is something called PFAS. Ahead of new federal regulations that go into effect in 2027, state environmental officials have begun looking for the insidious contaminants more commonly known as “forever chemicals,” highly toxic substances used for decades in food packaging and water- and fire-proofing materials.

They started with water systems across the state that supplied tap water to schools, and more recently began directly testing schools on well water. They have found PFAS so far in 34 schools but declined to say which ones.

What are PFAS?

PFAS is and abbreviation for per- and polyfluoroalkyl substances. The chemicals have been widely used since the 1940s in firefighting foam and also in commercial products to make pans stick-proof and clothing water- and stain-resistant. They don’t easily break down, can be difficult and expensive to filter, and are now found in groundwater that eventually finds its way to our taps.

The water is a major way the chemicals get into, and build up, in our bodies. Over time, they contribute to immune and reproductive problems, cancers and liver and heart troubles in people.

What are the laws around PFAS?

The U.S. Environmental Protection Agency in April established allowable levels for six kinds of PFAS in drinking water, and gave public water systems until 2027 to adhere to monitoring and consumer notification requirements and until 2029 to fix the systems.

That means switching to an uncontaminated source of water or installing treatment systems. Schools, in the meantime, may switch to bottled water, though the feds don’t regulate PFAS in that yet, either.

Up to 10% of the water systems may need to take some actions, the EPA estimates, and costs are expected to be considerable, $1.5 billion per year. There are 66,000 public water systems nationwide.

The EPA is providing $125 million to Maryland to address PFAS pollution in water systems in the state over five years, according to the Maryland Department of the Environment.

How is Maryland responding?

Maryland has already passed laws to ban PFAS in certain consumer products. It hasn’t adopted its own drinking water requirements, but officials have already begun testing according to the federal requirements, said Jay Apperson, a department spokesman.

Unlike lead, which can contaminate water through pipes and other fixtures, PFAS contamination for most schools comes from water systems, so that’s where the testing is done, he said. They’ve already gathered data on PFAS levels from more than 450 community water systems serving nearly 90% of the state’s population, Apperson said.

Last December, the state also began testing the smaller number of schools and day cares on well water rather than a utility. The state has so far tested 188 schools and found 34 with PFAS levels above the standards. Apperson declined to identify the schools or locations but said parents should be notified.

Apperson said the state has found some above the new federal threshold of 4 parts per trillion, and is working to help them find alternative water sources where available.

What happens when school water contains PFAS?

Even though it’s not yet mandatory under the federal rules, the state is recommending that schools with results above the federal standards notify parents of the results and create a remediation plan. Same for water utilities.

Apperson said the state is also recommending schools with the highest PFAS levels start work now because finding and implementing a solution could be time-consuming, and schools may also be able to apply for federal grant funding.

The state also recommends schools with high levels provide bottled water in the meantime.

Among those sending home letters were Harford County schools. Jillian Lader, spokeswoman for the system, noted it wasn’t mandatory but the schools immediately notified families based on the state’s recommendation.

Students and staff at five schools need to avoid consumption until the problem can be remediated. The schools will provide bottled water in the meantime. PFAS were detected in water at five other schools at levels below the standards. The school system determined remediation wasn’t needed, but parents were still notified.

Howard County schools also sent home letters, signaling at least three schools had PFAS levels above the standard, two below the standard and one where no PFAS were found. Bottled water will be provided at schools with the higher levels of PFAS as officials explore a water treatment system, the letters said.

Baltimore City schools, meanwhile, are already predominately using bottled water because of the threat of lead from the city’s aging system of pipes.

Testing will continue statewide at the schools with well water and at water systems.

What else should families know?

People with homes on well water can have them tested themselves. The state has a fact sheet on that. Utilities are also supposed to notify consumers of elevated PFAS and distribute annual Consumer Confidence Reports that can be found on the state’s website.

Those who find there are PFAS in their drinking water may want to use pitcher filters and home-based water filters to reduce exposure. The EPA recommends looking for ones that are certified to reduce PFAS, though none are yet certified to reduce PFAS to the new standards.

The Environmental Working Group has been doing its own water sampling, and has a map showing where they found PFAS above standards.

The research and advocacy group hasn’t tested at schools, but Sydney Evans, senior science analyst there, said the PFAS the state found were “deeply alarming.” The group was relieved that the schools shut off the drinking water.

The group also tested some water filters and has some recommendations.