The new law sets monitoring and abatement standards for the PFAS class of chemicals used in products like non-stick pans, food packaging and rain coats to resist oils and water. PFAS, or per- and polyfluoroalkyl substances, take longer to break down in the environment, and research shows the compounds may be harmful to humans and animals.

“PFAS are potentially toxic to humans even in very small concentrations and pose a wide range of health threats,” the new law reads. “They are suspected to cause cancer and have been linked to growth, learning, and behavioral problems in infants and children. They can also cause problems with fertility and pregnancy; compromise immune systems; and interfere with natural hormones and with liver, thyroid, and pancreatic function. Developing fetuses and newborn babies are particularly vulnerable to PFAS.”

James Crowley, attorney with the Conservation Law Foundation’s Rhode Island office, which advocated for the legislation, called the law “a big step forward.”

“This is a pretty major environmental issue that needed to be dealt with,” Crowley said. “It's important to take state action, because oftentimes, the federal process takes a very long time.”

Under the new law, the threshold for PFAS in all public drinking water systems is 20 parts per trillion for six specific compounds: perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluorohexane sulfonic acid (PFHxS), perfluorononanoic acid (PFNA), perfluoroheptanoic acid (PFHpA), and perfluorodecanoic acid (PFDA).

If a public water system tests above that standard, it will be required to provide alternative potable drinking water to customers until it addresses the problem and tests at acceptable levels. The Environmental Protection Agency issued an advisory earlier this month, saying PFAS could be harmful in even lower levels.

A news release from the EPA said that the agency “recommends states, Tribes, territories, and drinking water utilities that detect PFOA and PFOS take steps to reduce exposure. Most uses of PFOA and PFOS were voluntarily phased out by U.S. manufacturers, although there are a limited number of ongoing uses, and these chemicals remain in the environment due to their lack of degradation.”

Crowley of the Conservation Law Foundation said he expects state regulations will evolve over time as scientists learn more about the effects of the compounds.

Other New England states already have similar laws in place. Past testing has found PFAS levels above the maximum under the new law in municipalities around Rhode Island, including much of South County and the western part of the state.

Public water systems are required to comply with the new testing requirements by July 1, 2023. The law also sets standards for ground and surface waters.

Alex Nunes can be reached at anunes@thepublicsradio.org