A strong smell of rotten eggs wafted through far-flung parts of Southern California Monday, disturbing children at school in the Moreno Valley and wrinkling noses as far away as the Simi and San Fernando valleys.
The Air Quality Management District has been investigating the smell, which has prompted many residents to call 911. Results from air-quality samples could be available as soon as Tuesday.
There has been considerable speculation that the odor is coming from a fish die-off at the Salton Sea near Indio. The Air Quality Management District released this statement, in part, Monday night:
Air quality officials are continuing to investigate the source of a rotten-egg odor reported last night and today across much of Southern California, from the Salton Sea to the San Fernando Valley.
"Several factors indicate that the Salton Sea may have been the source of these odors," said Barry Wallerstein, executive officer for the South Coast Air Quality Management District (AQMD). "However we do not have any definitive evidence to pinpoint the Salton Sea or any other source yet."
Several sources have reported hot weather and a possible release of bacteria from the bottom of the sea due to winds there. Those conditions could cause strong sulfur odors.
Andrew Schlange, interim general manager of the Salton Sea Authority, echoed that hesitation to NBC4 earlier in the day, saying that it is not yet clear whether the inland sea is the culprit.
"We are in the process of trying to track it down," Schlange said. It would be unusual, he said, for a fish die-off to cause odors so far from the Salton Sea.
The smell may not be coming from the Salton Sea at all, he said. Or if it is from the Salton Sea, there could be other reasons for it.
For example, Schlange said, high winds that ripped through the area last night might have disturbed still water underneath the surface, bringing up a foul odor. That hypothesis was echoed by Air Quality officials Monday night.
Emergency personnel at the Los Angeles Fire Department were also trying to track down the smell. But by mid-morning, little information was available, spokesman Brian Humphrey said.
"LAFD is not aware of any specific hazard associated with the odor," Humphrey said in a fire department email alert.
The odor "has been sensed across vast expanses of Southern California since early this morning," he wrote.
Porter Ranch resident Cheryl Shapiro said she thought "the dogs brought something in," until her son-in-law called and said he smelled sulfur in the air.
A strong sulfur smell reached Palm Springs Sunday night after heavy winds began whipping through the area.
At Rainbow Ridge Elementary School in Moreno Valley, the smell was particularly bad at about 7:15 a.m. Monday, Kymberlee Henry-Davis said in an email to NBC4.
"All of the children were holding their noses," Henry-Davis wrote. "I even saw a child vomiting."