What to know about LA chemical tank set to explode or leak

U.S. Los Angeles tank holding dangerous chemicals is set to explode or leak, officials say. Here's what to know By Kerry Breen Kerry Breen News Editor Kerry Breen is a news editor at CBSNews.com. A graduate of New York University's Arthur L. Carter School of Journalism, she previously worked at NBC News' TODAY Digital. She covers current events, breaking news and issues including substance use. Read Full Bio Kerry Breen May 23, 2026 / 11:20 AM EDT / CBS News Add CBS News on Google Tens of thousands of Southern California residents have been evacuated after officials warned a leaking chemical tank holding a "highly flammable" substance at an aerospace facility would inevitably fail and potentially explode. The tank at GKN Aerospace is estimated to contain 7,000 gallons of methyl methacrylate, a "highly volatile" substance used in the production of plastics, according to Orange County Fire Authority Chief Craig Covey. It is not clear when the tank will fail, Covey said.Methyl methacrylate is a flammable plastic epoxy that generates its own heat. That means if it leaks into the atmosphere, any spark or flash could lead to an uncontrolled fire or explosion, said Elias Picazo, an associate professor of chemistry at the University of Southern California. At the moment, fire officials are working to keep the tank cooled.Covey told CBS Los Angeles that this is "the most significantly dangerous event" he's been a part of in his decades in fire service. "This is bad as I've ever seen," he added. So far, no injuries or deaths have been reported. GKN Aerospace is in Garden Grove, a town about 38 miles south of Los Angeles.  Emergency personnel respond to a hazardous materials incident at GKN Aerospace in Garden Grove, Los Angeles.  Allen J. Schaben/Los Angeles Times via Getty Images Health risks of methyl methacrylate Methyl methacrylate is a respiratory irritant, health experts told CBS Los Angeles. Exposure to the chemical can cause lung, sk...