Drinking Water to be Studied for PFAS

On Monday the U.S. Environmental Protection Agency (EPA) announcedthe Fifth Unregulated Contaminant Monitoring Rule (UCMR 5) to establish nationwide monitoring for 29 per- and polyfluoroalkyl substances (PFAS) and lithium in drinking water. This action is essential to EPA’s “PFAS Strategic Roadmap.”

The Safe Drinking Water Act, (SDWA), is the Federal law that protects the public from drinking water contaminants that pose a known health concern. Only 91 contaminants are regulated by the Safe Drinking Water Act, yet according to the EPA, more than 80,000 chemicals are used within the United States. Not every drinking water contaminant with health consequence gets regulated because they may not be widely present in source waters. And not every regulated contaminant has health consequence. Some contaminants are regulated to control taste and odor. Though the SDWA was adopted in 1974, it has had significant amendments in 1986 and 1996.

The 1996 amendments to the SDWA created the Unregulated Contaminant Monitoring Rule, UCMR. This is the tool the EPA uses to determine if there are contaminants likely to pose a risk to the health of the nation. A contaminant is identified as being of a possible health concern in drinking water, by states, water systems, scientists or other sources.  Health information is collected and if appropriate, occurrence and exposure information are collected using the UCMR data collection program for preliminary risk assessment then a determination is then made on whether there exists an opportunity to reduce public health risks by regulation and the contaminant is then added to the Drinking Water Contaminant Candidate List. Once every five years, EPA issue a new list of no more than 30 unregulated contaminants to be monitored by public water systems. The national sampling program provides the EPA with a scientifically valid database on the occurrence of these emerging contaminants in drinking water supplies.

This time 29 of the 30 contaminants on the list are PFAS known as “forever chemicals” because they build up in our blood and organs, bioaccumulate, and do not break down in the environment. Currently, EPA has a health advisory level of 70 ppt as a screening level for groundwater contamination, not a health based maximum contaminant level (MCL) for drinking water. They have not yet established a health based MCL. The compounds in EPA’s list are a fraction of the entire PFAS class of thousands of different chemicals with hundreds in current use. Studies have found that exposure to very low levels of PFAS can increase the risk of cancer, harm fetal development and reduce vaccine effectiveness.

States that have found extensive PFAS drinking water contamination have set more health-protective limits or lower advisory levels than the EPA to protect their residents. For example, New Jersey has set a legal limit of 13 ppt for perfluorononanoic acid, or PFNA, and proposed enforceable limits of 14 ppt for PFOA and 13 ppt for PFOS. Other states such as Washington, Michigan, and North Carolina evaluating the extent of contamination in drinking water and can now use the UCMR to make their determination.

In February of 2021 the EPA made the final determinations to regulate two PFAS chemicals- perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) in drinking water and to not regulate six other PFAS contaminants that had been under consideration. The list of contaminants in the UCMR are: