Scores of people were exposed to jet fuel or fumes Tuesday when a Delta flight was forced to dump fuel over a Los Angeles schoolyard and school buildings during an emergency shortly after departing Los Angeles International Airport.
At least 20 children were treated for minor injuries after being exposed to the jet fuel, according to the Los Angeles County Fire Department. The department said more than 60 people were treated from seven schools in the area.
No one was taken to a hospital, and there were no evacuation orders.
The school district confirmed that students and staff were being treated for skin irritation and breathing problems after being exposed to the fuel.
"Students and staff were on the playground at the time and may have been sprayed by fuel or inhaled fumes," the Los Angeles Unified School District said.
Fire officials said they did not expect there to be any significant side effects.
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Delta Flight 89, on its way to Shanghai, experienced an engine issue that required it to return to LAX shortly after takeoff, the company said in a statement. The plane landed safely after the fuel release, which the airline said was required as part of the procedure.
"We are in touch with Los Angeles World Airports and the L.A. County Fire Department and share concerns regarding reported minor injuries to adults and children at a school in the area," Delta said.
The Federal Aviation Administration said it was looking into the reports that school children were being treated for fuel exposure.
The FAA also said that there are special fuel-dumping procedures for any aircraft operating from any major U.S. airport: “These procedures call for fuel to be dumped over designated unpopulated areas, typically at higher altitudes so the fuel atomizes and disperses before it reaches the ground."
The agency also said Wednesday that the Delta flight crew did not tell air traffic control that they needed to dump fuel. In a typical scenario, the crew would inform the tower of the issue so that control could direct the plane to a less populated area, according to the FAA.
LAX confirmed that it was aware of the Delta flight reporting a mechanical issue and conducting an “emergency fuel release” before returning.
“We are concerned about reports of impacts on the ground from the fuel release, and are in close communication with Delta and first responders as their investigations continue,” the airport said on its Twitter account.