The US Environmental Protection Agency (EPA) has increased acts of environmental deregulation under President Donald Trump.

But a new rule—in the process of being finalized—would have an even more significant effect by restricting which studies EPA employees could use when drafting new regulations.

The rule would require EPA rule-makers to use only studies based on public data, in the name of transparency.

Such a requirement would make it impossible, for example, to use the countless studies that were based on individuals' medical data.

This type of analysis—showing the effects of air pollution on quality of life—is the foundation of a large number of environmental regulations.

The EPA also intends to make the transparency rule retroactive, according to The New York Times, which could call into question decades of regulations on air quality, water mercury levels or lead levels in paint.

"As leaders of peer-reviewed journals, we support open sharing of research data, but we also recognize the validity of scientific studies that, for confidentiality reasons, cannot indiscriminately share absolutely all data," wrote the editors-in-chief of Science, Nature, PLOS, PNAS, Cell Press and The Lancet.

They pointed to genetic studies that allowed researchers to find mutations that caused certain diseases.

Their main concern is that the new rule, even if not retroactive, would weaken regulations when they need to be updated.

"That would be a catastrophe," they wrote.

The EPA has not yet announced the date for the new regulation's finalization.