(The Hill) – A federal court on Tuesday tossed out a decision from the Environmental Protection Agency (EPA) not to regulate a chemical used in rocket fuel in drinking water. 

The Trump administration decided in 2020 not to regulate a chemical called perchlorate that can interfere with thyroid function and may harm fetal brain development. The Biden administration upheld that decision last year. 

But, a federal appeals court in Washington, D.C., reversed the decision on Tuesday.

The opinion of the three-judge panel, authored by David Sentelle — a Reagan administration appointee — argued that the Safe Drinking Water Act did not give the EPA the authority to reverse a 2011 decision in favor of issuing drinking water standards for perchlorate.

A concurring opinion from Florence Pan, a Biden appointee, disagreed on the statutory authority question, but agreed with the ultimate decision for other reasons. Namely, Pan found that the agency was working with a “biased dataset that was selectively updated” and was based on inadequate health goals. 

When it made the decision not to regulate the chemical, the Trump administration said there was not a “meaningful opportunity for health risk reduction.”

It said that the number of people who could be consuming the chemical at concerning levels could be between 26,000 and 620,000, which it said was not enough to take action. 

When it upheld the decision, the Biden administration said that it was based on the best available science. 

The Natural Resources Defense Council sued over the issue in 2020. 

An EPA spokesperson said that the agency was reviewing the decision. 

In addition to being used in rocket fuel, perchlorate can also be found in explosives, fireworks and road flares.