This story was originally published by CalMatters. Sign up for their newsletters.
Tens of thousands of Garden Grove residents recently returned home after a cracked chemical tank prompted evacuations. The incident in late May exposed a large and ongoing threat: California communities are vulnerable to dangerous accidents tied to the plastics supply chain.
GKN Aerospace owns the tank that cracked. It produces chemicals used to manufacture plastics. A tank like the one in Garden Grove is a key part of the plastics supply chain, and warehouse raw materials for the plastics industry.
Methyl methacrylate, the chemical that was in danger of spilling, is a raw, oil- and gas-derived material that is mixed with other chemicals to create acrylic plastics. About 80% of methyl methacrylate monomers produced globally go toward making acrylic plastics.
It’s alarming that the tank’s cooling system failed and how unprepared oversight authorities were to respond.
Rather than being resolved through safety protocols or effective regulatory oversight, the crisis at Garden Grove only ended when the tank cracked on its own, releasing built up pressure and avoiding a violent explosion or a leak. Had this not occurred, it’s likely responders would not have been able to safely contain the leak.
The Garden Grove emergency will have far-reaching consequences for the public. It’s a warning about the public health risks tied to plastics manufacturing and chemical production.
Many chemicals used in plastics manufacturing are highly flammable and are carcinogenic toxins. They can contaminate air and water through factory leakage or volatile explosions and can have long-term health impacts to internal organs and irritate skin and eyes. Chemical contamination can spread through soil and water systems, affecting ecosystems and food supplies.
The Garden Grove crisis was not an isolated incident. Across the United States, chemical facilities involved in plastics production have experienced fires, leaks and explosions with devastating consequences.
Chemical releases at plants in Monaca, Pennsylvania, Houston and Nitro, West Virginia — where two workers died and five were injured — illustrate the dangers posed by volatile compounds used to manufacture plastics. In 2023, a chemical plant in Bristol, Pennsylvania, leaked up to 12,000 gallons of plastics-manufacturing chemicals into the Delaware River, where millions of people get their drinking water.
These incidents are part of the mid-stream footprint of the plastics supply chain, which creates community-level, chemical exposure risks that should be recognized as part of plastic’s full impact, alongside the more commonly cited problems of microplastics and plastic waste.
The UCLA Luskin Center for Innovation has been studying the plastics supply chain and its impact on the public health of California communities. We have identified more than 800 plastic manufacturing facilities that use or emit hazardous and toxic chemicals in the state.
The greatest concentration of plastics and plastics-chemicals manufacturing is in the Greater L.A. region, with notable hotspots around Carson, East Los Angeles and Ontario. Smaller but significant hubs are in the San Francisco Bay Area, and near San Diego and Oceanside.
The proximity of these plastics-chemical plants to densely populated areas shows the significant health risks of our dependence on plastics. It’s putting us all at risk.
In a report released in 2025, Luskin Center researchers showed how oil and gas industries are increasing their investment in chemicals for plastics production, which will increase the likelihood of environmental emergencies like the one in Garden Grove.
California cannot continue expanding plastics and petrochemical infrastructure while communities bear the risks. Policymakers should strengthen oversight of hazardous, plastics-related facilities and accelerate efforts to reduce the dependence on plastics production.
