As AI data centers expand, new cooling chemicals raise PFAS concerns

The artificial intelligence race is creating demand for more than data centers and electricity. It is also creating a new market for the chemicals needed to keep increasingly powerful computer chips from overheating.

2026-08-25

Some of those cooling technologies rely on PFAS, a broad class of fluorinated compounds already responsible for widespread drinking water contamination in North Carolina.

Now, Chemours, the company at the center of the Cape Fear PFAS contamination, is developing a fluorinated fluid called Opteon 2P50 to cool high-powered data center servers.

The chemical is still awaiting federal approval and is not yet commercially available in the United States. Chemours says it could dramatically reduce the water and energy required for cooling, an appealing proposition as communities raise concerns about the resource demands of new data centers.

Those concerns are already playing out across North Carolina, where residents are asking what large data centers could mean for local water supplies.

For Laura McKelvey, a Chapel Hill resident who spent 34 years working for the U.S. Environmental Protection Agency, the concern extends beyond how much water data centers use.

“I worry about discharge,” McKelvey said. “There’s leaks and there’s maintenance.”

WRAL examined what companies developing data centers in North Carolina say they plan to use for cooling, what state regulators require them to disclose, and what is known about a new generation of fluorinated cooling fluids.

Why AI is changing how data centers are cooled

The more computing power packed into a data center, the more heat it has to manage. As AI accelerates demand for increasingly powerful chips, keeping those servers cool is becoming a bigger engineering challenge — and pushing some companies to look beyond traditional air- and water-based cooling.

One emerging option is two-phase immersion cooling, which essentially gives the servers a bath. Computer equipment is submerged in a liquid that does not conduct electricity. As the servers heat up, the fluid boils into vapor, then condenses back into liquid to be used again.

Chemours is developing Opteon 2P50 for this type of cooling and says the closed-loop design allows the fluid to be captured and reused.

PFAS are a large family of manufactured chemicals known for their persistence in the environment. Some have been linked to cancers, decreased fertility, immune system effects, and other health problems.

A coalition of 17 environmental organizations, including the Natural Resources Defense Council (NRDC) and Earthjustice, is urging the EPA not to approve 2P50 and other new PFAS uses. Their concern is not only what happens while the fluid is circulating inside a data center, but what could be released during its manufacture, use, maintenance, and eventual disposal.

“There's no real closed-loop system when it comes to PFAS,” said Drew Ball, Southeast campaigns director for NRDC.

Chemours says 2P50 is intended for sealed, closed-loop systems where the fluid can be reclaimed, reprocessed, and reused. The company says PFAS should not be treated as a single class because individual chemicals have different properties and potential risks, and that 2P50 should be evaluated based on its specific characteristics and potential for exposure.

What Chemours has — and hasn't — disclosed about 2P50

Chemours says it has provided the EPA with “extensive technical and scientific information” about 2P50 as the agency reviews the chemical for commercial use in the United States.

WRAL repeatedly asked Chemours to provide those data and studies, including results from full-scale testing, information about potential emissions and atmospheric breakdown products, and the underlying data supporting its claims about energy and water savings.

After more than a week of correspondence, Chemours did not provide the requested data.

WRAL also asked about an estimated annual evaporative loss rate of approximately 0.7% attributed to Chemours. The company did not confirm that estimate, provide the data behind it, or offer a different expected loss rate.

Chemours has publicly promoted 2P50 since at least 2023, saying customer trials demonstrated its performance and that the technology could reduce cooling energy use by more than 90% and nearly eliminate water use. The company did not provide WRAL with the underlying data requested to independently evaluate those claims.

Chemours' PFAS history in North Carolina

For decades, Chemours and its predecessor, DuPont, released PFAS from Fayetteville Works into the Cape Fear River and the air, contaminating drinking water for hundreds of thousands of people. 

The cleanup is extensive. Under a 2019 consent order with the state and Cape Fear River Watch, Chemours has been required to provide safe drinking water to affected residents, sharply reduce air emissions and address contaminated groundwater. 

Chemours said in a statement that it has invested more than $400 million to reduce PFAS emissions at Fayetteville Works and about $160 million in private well testing. Among the pollution controls required under the consent order was a thermal oxidizer, technology that had been used industrially for decades.

Chemours did not answer questions about what PFAS pollution controls it has undertaken beyond its legal requirements.

Chemours says it does not manufacture 2P50, its precursors or intermediates at Fayetteville Works and told WRAL “there are no plans to change that.”

What Amazon and Microsoft plan to use in North Carolina

Amazon says its planned Richmond County facilities will not use liquid immersion cooling. Instead, the company expects to cool its servers with outside air about 93% of the year, without using water for cooling during those periods. On the hottest days, it plans to switch to evaporative cooling.

That water will be treated with sodium hypochlorite, a disinfectant commonly used in municipal water systems, and chemicals to balance its pH, according to Amazon. The company said total chlorine will be the only treatment chemical remaining in its discharge and that the water will meet applicable discharge requirements.

Microsoft is developing data centers in Person and Catawba counties and says it “does not add PFAS chemicals to datacenter cooling operations.”

For its Person County project, Microsoft has announced plans for air-cooled chillers and a closed, recirculating water loop. The company told WRAL its data center cooling water is not treated with chemicals or additives, though some Microsoft facilities use propylene glycol in closed-loop systems. It also pointed to leak detection, automatic shutdown systems and spill-response procedures designed to contain releases.

What must data centers disclose to North Carolina regulators?

The rapid expansion of data centers in North Carolina leaves a broader question for state regulators: How much must North Carolina know about the chemicals used to cool a data center before it begins operating?

The NC Department of Environmental Quality says data center permit applications are reviewed under existing state and federal environmental laws, with requirements determined by the design of each project.

The agency did not answer more specific questions from WRAL about whether developers must disclose all chemicals used in their cooling systems, which contaminants must be tested for in cooling wastewater, or how regulators would detect a fluorinated chemical that is not already subject to monitoring requirements.

North Carolina lawmakers considered adding some guardrails this year. Senate Bill 730 passed the House in June with provisions addressing some of the costs and resource demands associated with large data centers, including a requirement for certain facilities to use closed-loop cooling designed to minimize water consumption. The bill stalled after returning to the Senate.

Ball said development is moving faster than regulators' understanding of what these increasingly complex facilities could release.

“We don't even have a handle on what type of pollution is coming out of these systems right now,” Ball said. “We need better standards; we need better research in place because they're getting ahead of our local elected officials and our ability to track what's coming out of these things.”

Newer cooling technologies could bring real environmental benefits. Systems that use less water and electricity could ease two of the biggest pressures associated with data centers. Chemours says immersion cooling can do both, while Amazon and Microsoft say their North Carolina designs can reduce water use without it.

The challenge is knowing the full trade-off before those systems are operating at scale. Without clear disclosure of the chemicals being used and monitoring designed to detect what could escape, regulators and communities may not have that picture until after a problem emerges.

North Carolina has learned that lesson with PFAS before. The state has spent years tracing contamination through rivers, groundwater, private wells, and air after the chemicals were already in the environment. The data center buildout offers a chance to understand the environmental footprint of new cooling technologies before they become widespread, rather than trying to reconstruct it afterward.