Odor of Stagnant Water Sickens Workers in Cypress

Dozens of workers at a Mitsubishi plant were rushed to local hospitals and hundreds of others were evacuated Thursday morning after a foul odor from stagnant water stored inside a sprinkler system made them sick, firefighters said.

The building’s 250 employees were evacuated about 9 a.m. after workers experienced headaches, vomiting and difficulty breathing, said Dennis Shell, spokesman for the Orange County Fire Authority. All told, 37 people were taken to eight hospitals, where they were treated and released, authorities said.

“Think of the worst water you’ve ever smelled and multiply that by 10,” Shell said. “People were throwing up from the stench. . . . But it’s not toxic.”

Firefighters were summoned to the plant on the 10800 block of Holder Street, where three women, one of whom is seven months pregnant, reported nausea and other symptoms. After the women were taken to Los Alamitos Medical Center, a few more employees walked out with similar complaints, Fire Capt. Jack Cheak said.

“We had thought that was the end of it,” Cheak said. “But then another walked out, and then two more. Before we knew it, we had nine people who had gotten sick.”

Firefighters then ordered the building evacuated. Seven huge fans were used to clear out the air, Shell said.

Most employees returned to work a few hours later.

Hazardous material investigators said the foul smell came from stagnant water stored inside the fire-protection sprinkler system, which was being serviced Thursday. The smell was released into the air-conditioning system and circulated throughout the facility’s third floor, Shell said.

The incident prompted firefighters to set up a “mass casualty area,” where workers could get immediate medical attention. They also activated the Hospital Emergency Alert Radio System, which is reserved for large-scale emergencies that require numerous hospitalizations.

The last time Shell and other firefighters remember the hospital emergency system being activated was in August 1986, when a passenger plane collided with a private plane over Cerritos, killing more than 60 people. Orange County firefighters assisted in that accident.

“It has to be a very serious situation before we activate it,” Shell said. “In this case, we had a strong possibility that there is a large number of people who are seriously ill. We’re very thankful that that didn’t happen, but it could have.”

Also contributing to this report was Times correspondent John Pope.