The Biden administration has launched a new initiative to crack down on smugglers at U.S. borders and ports. The concern isn't drugs or counterfeit goods, though; it's a refrigerant that's also a dangerous greenhouse gas.

The Environmental Protection Agency, Customs and Border Protection and other agencies are arming themselves with new weapons—like AI tools that can pick out suspicious shipments—and rethinking ways of teaming up to combat the threat.

"We're deploying our enforcement authorities in ways we never have before to combat climate change," said David Uhlmann, head of EPA's enforcement division. In early September, the agency issued an enforcement alert to spotlight the problem.

The U.S. has experienced a smuggling epidemic like this before, with HFCs' predecessors. When dozens of nations agreed in the 1990s to ban chlorofluorocarbons (CFCs), one of the most unwelcome outcomes was the formation of a black market for people who wanted to keep using refrigerants. The market grew so fast that, by mid-decade, $500 million of CFCs were being illegally traded each year, according to the United Nations Environment Program.

Now, the Biden administration is attempting to disrupt an eerily similar pattern from playing out as a phase-out of HFCs leads to a burgeoning black market. So far, the results of the crackdown have been striking. Since the start of fiscal year 2024, the Biden administration has stopped roughly 25 illegal shipments of hydrofluorocarbons (HFCs), according to an EPA spokesman. Those shipments account for more than 211,000 metric tons of carbon dioxide, the equivalent of 50,000 gas-powered vehicles driving for a year.

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