It is highly unlikely that the troubled San Onofre nuclear plant is the source of the flammable substance that caused some colorful beach rocks to burst into flames in a pocket of a woman's cargo shorts, leaving her with second and third-degree burns.
Scientists weren't so quick, however, to rule out the Marine base at nearby Camp Pendleton as a source.
"I would be very doubtful about that possibility," James Earthman, a professor of chemical engineering and material science at UC Irvine, said of the possibility that the rocks, which showed traces of a "phosphorous substance" after tests, could have been somehow contaminated by the nearby nuclear facility.
Officials with Southern California Edison, which oversees the San Onofre facility, dismissed the chance of any link with the burning rocks.
"San Onofre Nuclear Generating Station does not use this chemical form at the plant nor is it a byproduct of the plant's operation," Jennifer Manfe, a company spokeswoman, said in a statement.
Another possible source could have been Camp Pendleton, which hugs the north San Diego coastline near the state beach where the women and her children gathered the rocks. Earthman would not rule out that possibility.
A Marine spokesman said Friday there is no indication the flammable material came from anything being used during training at the base. But, he added, the base is prepared to help in an investigation, if asked.
The San Clemente woman, identified as Lyn Hiner in an interview Friday with ABC News, remains hospitalized with second- and third-degree burns after the colored rocks her daughters collected Saturday at San Onofre State Beach ignited hours later in the pocket of her cargo shorts, after she had returned home.
"We were taking about who was going to pick up the babysitter," Hiner recounted in the interview on "Good Morning America."
"And all of a sudden, something on my leg just sort of started to bother me, so I started thinking it was a bug bite, so I slapped it," he said. "And the next thing I know my pants were on fire."