Both directions of the 215 Freeway in Perris have been reopened and evacuation orders have been lifted Saturday after a hazardous chemical leak prompted closures.
The leak began Thursday night when a tanker carrying the chemical styrene began overheating and leaking into the air.
"Styrene is a chemical used in latex, synthetic rubber and polystyrene resins, which are used in plastic packages, disposable cups and containers, insulation and other products," the CDC says on its website. Exposure is possible by breathing it in through the air. Exposure to large amounts of styrene can irritate the eyes and respiratory passages.
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Styrene is found indoors due to operating photocopiers and laser printers, and from cigarette smoke, according to the Centers for Disease Control and Prevention. It's also found naturally in some plants.
A plume of smoke from the leak caused residents who live nearby to feel sick.
Firefighters described it as a ticking time bomb that could explode at any time.
Typically, Cal Fire Riverside County Chief John Crater said, styrene sits at around 85 degrees Farenheit. The roughly 188,000 pounds of styrene in the tank had reached temperatures up to 323 degrees.
The cause of the overheating remains unclear.
"I made about three steps before I could get outside and immediately vomited," said Steven Moore an evacuated Perris resident. "I didn't know what it was, I was dizzy and almost passed out."
Firefighters say that the tanker was filled in Texas and had been in transit for more than 50 days and they are confident that the current evacuation zone is large enough to protect neighbors from potential fumes.
