October 13, 2026

Understanding PFAS Exposure in PEX-a Pipe

By Maddy Dolby

Per-and polyfluoroalkyl substances, also known as PFAS, are a large group of synthetic chemicals used to make consumer products water resistant, grease resistant, and heat resilient. Many call them “forever chemicals” because they don’t break down easily.

PFAS reach and move through the Earth in various ways. They can soak into the soil from rainwater and irrigation, landfills and waste, biosolids and sludge, and air deposition. They can also be found in firefighting foam. Aqueous film-forming foams are commonly used at airports, military bases, and industrial sites. These foams can sink directly into the soil during training or emergency responses.

While metallic pipes themselves do not inherently contain these “forever chemicals,” PFAS may still be present in certain metal plating, coating, or finishing processes used on pipes, as well as in some associated components, such as seals and fittings.

PFAS is not used in the ingredients to manufacture PEX-a pipe; they are not required to create the pipe or the base high-density polyethylene (HDPE) polymer.

PFAS do not chemically degrade or structurally damage PEX-a pipe. Many PFAS dissolve readily in water and bind weakly to soil, allowing them to move quickly through the ground and into water supplies.

The Sustainability Benefits of PEX-a Pipe

Flexible PEX-a pipe resists corrosion and scale buildup, is resilient in freeze/thaw cycles, has superior flow properties, and offers a lower carbon footprint compared to metallic piping (25% lower total greenhouse gas emissions and 3% lower climate change impact over the entire lifecycle of the product).

Uponor PEX-a piping systems support various sustainability efforts by contributing to decarbonization goals, net-zero targets, and electrification strategies. The production and installation processes for the pipe are energy efficient, helping to lower carbon footprints, and the durability of the product helps minimize waste and environmental impact, aligning with net-zero objectives. Additionally, Uponor PEX-a piping heating and cooling systems are compatible with geothermal and solar energy sources to further support sustainable building.

For more information about the sustainability benefits of PEX piping systems, check out this blog.