Per- and Polyfluoroalkyl Substances (PFAS)

PFAS were a component of aqueous film-forming foams used to fight liquid fuel fires
Source: National Archives, US Air Force (USAF) Fire fighters with the 167th Air Wing (AW), West Virginia Air National Guard (WVANG), quench a simulated aircraft fire during a training session

Per- and polyfluoroalkyl substances (PFAS) are called "forever chemicals" because the molecules are so tightly bonded that natural degradation occurs very slowly. There are 12,000 chemicals in the PFAS group.

PFAS were used in manufacture of stain and water repellent material, food packaging and other consumer products, plus fire-fighting foam. A detectable level of PFAS is estimated to be present in 45% of drinking water supplies in the United States, ranging from 8% in rural area served by wells to 70% in urban areas drawing water from lakes and rivers.¹

PFAS molecules form "forever chemicals" because bonds between atoms are especially strong and thus slow to break apart
Source: Wikipedia, Sustancias perfluoroalquiladas

By 2015, at last one of 32 types of PFAS were found in the blood of 95% of Americans. The health effects were not fully understood, but researchers were targeting cancers, delayed development of children, and fertility impacts. At last 75% of tap water tested in urban areas had a last one form of PFAS. In rural areas, 25% of drinking water systems were contaminated.²

In 2023, the Environmental Protection Agency (EPA) proposed drinking water standards to limit PFAs to no more than 4 parts per trillion:³

On March 14, 2023, EPA announced the proposed National Primary Drinking Water Regulation (NPDWR) for six PFAS including perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluorononanoic acid (PFNA), hexafluoropropylene oxide dimer acid (HFPO-DA, commonly known as GenX Chemicals), perfluorohexane sulfonic acid (PFHxS), and perfluorobutane sulfonic acid (PFBS)...

EPA is proposing a National Primary Drinking Water Regulation (NPDWR) to establish legally enforceable levels, called Maximum Contaminant Levels (MCLs), for six PFAS in drinking water. PFOA and PFOS as individual contaminants, and PFHxS, PFNA, PFBS, and HFPO-DA (commonly referred to as GenX Chemicals) as a PFAS mixture. EPA is also proposing health-based, non-enforceable Maximum Contaminant Level Goals (MCLGs) for these six PFAS.

Also in 2023, DuPont de Nemours Inc., the Chemours Company and Corteva Inc., settled a class action lawsuit and agreed to pay $1.2 billion for PFAS contamination in some drinking water systems. Separately, 3M agreed to pay $10.3 billion to provide funding for public water suppliers to test for PFAS and remove the chemicals.⁴

The technologies to remove PFAS from drinking water were still in early development stages. Options included activated carbon adsorption, ion exchange resins, and high-pressure membranes. Without a clear understanding of the investment required, suppliers of public drinking water had to speculate on the future costs to meet the proposed 4 parts per trillion standard.⁵

Drinking water is just one avenue for humans to ingest PFAS. In 2024, manufacturers of food packaging agreed voluntarily to stop using PFAS, which made hamburger wrappers and salad containers more oil-resistant. One university professor noted that the action by the manufacturers was significant in part because it limited PFAS exposure where consumers were unlikely to take action, because:⁶

Nobody reads the wrapper of their hamburger to see if it has PFAS or not.

The Environmental Protection Agency finalized its proposed rule fo limiting per- and polyfluoroalkyl substances on April 10, 2024. It was the first rule to deal with a new drinking water contaminant since 1996.

The Federal agency estimated the lower limits would reduce PFAS exposure for approximately 100 million people. The new rule forced drinking water suppliers, including public utilities, to clean up waste that others had put into waterways. Federal action was directed towards reducing the risks to drinking water customers rather than eliminating the discharge of PFAS, or the cleanup of sies leaking "forever chemicals" into water supplies.

The Environmental Protection Agency did announced the availability of $1 billion from the Bipartisan Infrastructure Law to fund implementation by the 6-10% of the 66,000 public drinking water systems that would have to take action. Technologies to reduce PFAS in drinking water included granular activated carbon, reverse osmosis, or ion exchange systems. ⁷

Links

• American Water Works Association (AWWA)
• Per- and Polyfluoroalkyl Substances
• Environmental Protection Agency
• PFAS Explained
• Fairfax Water
• Poly- and Perfluoroalkyl Substances (PFAS) Overview and Current Activities
• Virginia Department of Environmental Quality (DEQ)
• Per- and Polyfluoroalkyl Substances (PFAS)
• Virginia Department of Health
Per- and Polyfluoroalkyl Substances (PFAS) in Drinking Water

References