Rhode Island has a serious issue with per- and polyfluoroalkyl substances, better known as PFAS.

PFAS are called “forever chemicals” because once released into the environment they don’t break down, and they build up in human blood and organs. Exposure to PFAS increases the risk of cancer and harms fetus development, according to an increasing amount of research.

One of the more disturbing effects of PFAS is that they reduce the effectiveness of vaccines such as diphtheria. Studies by the Centers for Disease Control and Prevention show that the blood of nearly all Americans is contaminated with PFAS.

Fortunately, the Rhode Island Department of Health (DOH) has been testing wells and water systems throughout the state since 2017. At a Feb. 27 Senate committee hearing on PFAS, the state agency released its test data (see graphic above).

The committee was holding a hearing on bills to regulate PFAS in Rhode Island. One of the bills requires that if monitoring tests confirm the presence of PFAS in excess of 20 parts per trillion (ppt), the DOH “shall direct the public water supply system to implement treatment or other remedy to reduce the levels below the drinking water standard level.”

Last year, DOH tested every major drinking-water supply in the state and the water in every school that had its own well(s). In all, 87 percent of Rhode Islanders had their primary source of water tested.

Many of the sites that tested positive for PFAS were schools. Since children are more susceptible to the harmful effects of PFAS, ecoRI News plotted the PFAS contamination data for schools. These are only sites for schools that have their own wells. Schools that receive their water from town sources weren’t tested.

The following is a summary of the DOH test findings: 132 sites were tested for PFAS; 48 percent tested positive for PFAS; 24 percent had PFAS levels above the recommended standard of 20 ppt; 35 percent of the sites tested were schools; 43 percent of the schools tested had PFAS levels above the recommended standard of 20 ppt.

The state’s data is consistent with several other studies. For example, the Environmental Working Group has published an interactive map that lists sites all over the country at which PFAS were detected.

It shows that Rhode Island has more sites with PFAS than the much larger states of Connecticut and Massachusetts (see graphic below). However, this is misleading, as illustrated by New Jersey. PFAS shows up in all states that have testing programs. The fact that New Jersey has a significant testing program explains why there are so many dots in New Jersey.

Tests were conducted at military sites in Connecticut (see the purple dots in graphic below) and PFAS were found at those sites. Therefore, it’s reasonable to conclude that there are no other PFAS dots in Connecticut because the state hasn’t carried out such tests.

PFAS are present in firefighting foams used by both civilian and military fire departments. As a result, military sites are significant sources of PFAS contamination.

Rhode Island’s military sites with significant concentrations of PFAS are: Naval Station Newport at 420 ppt, more than 20 times the level proposed for Rhode Island; and Quonset State Airport at 2,865 ppt, more than 100 times the proposed level.

While contamination at military sites is the Department of Defense’s problem to remedy, the DOH and the Rhode Island Department of Environmental Management plan to monitor the areas surrounding those sites to ensure that the chemicals don’t leech into surrounding waterways.

But how much PFAS is harmful? It’s largely undecided.

Bill S2235, for instance, proposes remedial action when the detected amounts of PFAS exceed 20 ppt. However, there is growing scientific consensus that much lower levels of PFAS are harmful, especially to children and young adults.

In 2017, New Jersey lowered its limit from 40 ppt to 14.

In 2018, the Agency for Toxic Substances and Disease Registry proposed a drinking-water level of 11 ppt. That same year, the European Food Safety Authority set a drinking-water level of 6.5 ppt.

Michigan, which has serious PFAS problems, appointed a PFAS Science Advisory panel that concluded that if the goal is to protect the most vulnerable populations, the maximum contaminant level should be around 2 ppt for drinking water.

Roger Warburton, Ph.D., is a Newport, R.I., resident.