A group of Democratic lawmakers urged Environmental Protection Agency (EPA) Administrator Gina McCarthy Wednesday to reduce pollutants known to cause climate change.

Sen. Tom Carper (D-Del.) and Rep. Scott Peters (D-Calif.) led 16 other lawmakers in writing a letter to McCarthy, where they asked her to use the agency’s authority to reduce the use of hydrofluorocarbon (HFCs) compounds.

“We believe the EPA does not need to wait to implement smart policies that can help accelerate these transitions in the United States and globally,” the letter stated.

HFCs are used in refrigeration and air conditioning, but the European Union has implemented policy to encourage alternative products.

Scientists have said HFCs could account for 20 percent of greenhouse gas pollution by 2050.

“The agency should look to where market transitions are already underway and where EPA action could hasten the pace of those transitions, both domestically and elsewhere,” the lawmakers wrote. “We think that such actions would not only have significant cost-effective environmental benefits but would also strengthen the administration’s hand in the Montreal Protocol negotiations.”

The Montreal Protocol is a multi-national environmental initiative that the United States ratified in 1988. It aimed to reduce the use of ozone-depleting substances.

In addition to Carper and Peters, Sens. Diane Feinstein (D-Calif.), Chris Coons (D-Del.), Sheldon Whitehouse (D-R.I.), Chris Murphy (D-Conn.), Barbara Boxer (D-Calif.), Bob Menendez (D-N.J.), Ed Markey (D-Mass.), Kristen Gillibrand (D-N.Y.) ans Reps. Anna Eshoo (D-Calif.), Susan Davis (D-Calif.), Matt Cartwright (D-Pa.), Paul Tonko (D-N.Y.), Alan Lowenthal (D-Calif.) and Suzanne Bonamici (D-Ore.) signed the letter.