Washington DC - Trump administration officials are reconsidering whether greenhouse gases should be considered harmful to public health as the Environmental Protection Agency (EPA) rolls back regulations.

As part of a massive string of announcements that administrator Lee Zeldin labeled the "most consequential day of deregulation in American history," the EPA revealed that the agency would reconsider a landmark 2009 ruling.

The 2009 Endangerment Finding established that the six key greenhouse gases (carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbon, and sulfur hexafluoride) are harmful to human health in high concentrations.

EPA officials acknowledged in the finding that greenhouse gas pollution from motor vehicles and the burning of fossil fuels are a significant threat to public health and welfare.

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What was not introduced in the endangerment finding, however, were any measures that the US government or key polluters were expected to make to reduce emissions.

Effectively, while the 2009 Endangerment Finding does not impose any specific restrictions on Trump administration policy, it is inconvenient, as it cements the fact that greenhouse gases are harmful into law.

Lee Zeldin justified the decision to reconsider the landmark 2009 finding on the basis of promoting prosperity and energy security by making it easier for polluters to operate without having to worry about EPA regulations.

"The Trump Administration will not sacrifice national prosperity, energy security, and the freedom of our people for an agenda that throttles our industries, our mobility, and our consumer choice while benefiting adversaries overseas," Zeldin said in a press release.

"We will follow the science, the law, and common sense wherever it leads, and we will do so while advancing our commitment towards helping to deliver cleaner, healthier, and safer air, land, and water."

Environmental groups, however, dispute many of Zeldin's claims, including the idea that the 2009 Endangerment Finding was an ideological document. Many doubt the truth in his claim that his EPA is committed to delivering cleaner air, or even following the science at all.

"The Trump administration's ignorance is trumped only by its malice toward the planet," said Jason Rylander, legal director at the Center for Biological Diversity's (CBD) Climate Law Institute.

In a press release, the CBD reiterated that the finding was based on "robust and irrefutable" scientific evidence and emphasized that as the world's second-largest carbon polluter, the US needs to be world-leading in the fight against greenhouse gas pollution and climate change.

"Come hell and high water, raging fires and deadly heatwaves," Rylander said, "Trump and his cronies are bent on putting polluter profits ahead of people's lives. This move won't stand up in court. We're going to fight it every step of the way."