The dust residents described falling from the sky after an explosion at the Exxon Mobile refinery in Torrance on Wednesday is not hazardous but could be an irritant, according to the company.
In a statement shared with KPCC early Friday, Exxon Mobil described the material as a catalyst that is primarily composed of metal oxides and amorphous silica and said that it could cause irritation to the skin, eyes and throat.
It said the results of its testing of the material were consistent with those of an independent test requested by the Torrance Fire Department.
The company has set up a claims hotline for anyone who may have been impacted as a result of the incident. The number is 844-631-2539.
The explosion Wednesday prompted the company to activate its flare system to burn off hydrocarbons as a precautionary measure, a move that resulted in a startling display of fire and smoke coming from the refinery's stacks.
Exxon Mobil said it was cooperating with investigators to determine the cause and develop a repair plan.