Actor and environmental activist Mark Ruffalo appeared before a Congressional subcommittee on Tuesday to give testimony on chemical pollution and to promote his latest movie, Dark Waters, an indie drama based on the legal fight between attorney Robert Bilott and chemical giant DuPont.

But his appearance elicited sharp partisan division among members of the subcommittee.

Reps. Alexandria Ocasio-Cortez (D-NY) and Rashida Tlaib (D-MI) supported the Avengers: Endgame star’s decision to speak, while Republican members questioned why an actor with no technical background was giving testimony on a subject as complex as perfluoroalky and polyfluoroalkyl chemicals, or “PFAS” chemicals.

“It’s unclear to me why a Hollywood actor with no scientific expertise on PFAS chemicals would be called to testify today,” Rep. James Comer (R-KY) said in his opening comments as part of the House Oversight and Reform Subcommittee on Environment.

Rep. Fred Keller (R-PA) had even harsher words for Mark Ruffalo.

“The majority has called as their star witness an actor — that’s right an actor. An actor with no medical, no scientific or research expertise except for a few scenes as Dr. Bruce Banner. An actor that has a record of anti-business activism,” he said. “More importantly to Mr. Ruffalo… an actor with a movie premiering this week that attacks private sector job creators with loose facts and hyped up emotional rhetoric.”

Rep. Keller added: “I’m not sure if Mr Ruffalo is looking for an Academy Award for his performance in the upcoming movie or for his performance in this hearing.”

Reps. Comer and Keller said they support a bi-partisan solution to the problems posed by PFAS chemicals. But they also noted that the chemicals have important uses, including in certain firefighting foams.

Ruffalo stars in Dark Waters as Robert Bilott, an attorney who waged a war against DuPont, forcing the company to share documents on a chemical believed to have poisoned the ground and drinking water in certain states. Focus Features is set to open the indie movie Nov. 22 in limited release.

The actor spoke in impassioned tones Tuesday about the need for government action.

“We have done absolutely nothing. We have not stopped industrial releases of PFAS into the air and water,” Ruffalo said before the subcommittee. “Who should pay? The companies…. They knew they were toxic but failed to tell anyone.”

Rep. Tlaib praised the actor, saying “I think what you said is exactly what we need to do in Congress.”

She said there remains a culture of “so what?” that has led to inaction. “Corporate greed is tainting our democracy,” she said. “Put people before profits.”

Rep. Ocasio-Cortez also complimented Ruffalo for testifying, saying that it was “laughable” that Republicans would feel threatened by a movie.

Other Democrats who backed Ruffalo’s appearance included Rep. Debbie Wasserman-Schultz (D-FL) and Rep. Dan Kildee (D-MI).

“I’ll take help from anyone who will step up and help tell this story to the American people. Mark, keep doing what you’re doing,” Rep. Kildee said.

Ruffalo closed by saying he wants to see a bi-partisan solution from the subcommittee.

“I want to see that happen. It would be a travesty if that doesn’t happen.”

Earlier in the day, the Hollywood star appeared in a press conference with Bilott outside Capitol Hill. Mark Ruffalo spoke about Dark Waters and the need for government action to rein in corporations.

“We have a chance with this movie… to actually start to turn the tide on who is watching out for us,” the actor said.

“Are we a country that is going to be responsive to the people, and make sure that our people remain healthy? Or we only going to be responsible to the bottom lines of corporations and their greed? Because right now, the people are losing.”

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