A gasoline additive meant to make fuel burn more cleanly has been found in two Southern California lakes, Castaic and Pyramid, that provide drinking water to dozens of agencies, but the levels are considered to be safe, officials said.
California officials have commissioned studies to find out the additive's health effects, which have not been determined, authorities said Wednesday.Water officials only recently began testing reservoirs that store state water for methyl tertbutyl ether after some gas station employees and mechanics reported problems such as nose, throat and eye irritation, said Stefan Cajina, a sanitary engineer for the Department of Health Services, which has set the safety standard.
MTBE also has been found at other locations, including Lake Tahoe, Donner Lake, Shasta Lake, Don Pedro Reservoir and Pardee Reservoir.
"In tests on rodents, (MTBE) has caused cancer. But there has been no link made to effects on humans," Cajina said. "People have reported nose and throat irritation and other symptoms, but they haven't been definitively linked to MTBE. Studies have been inconclusive."
Monitoring of Castaic and Pyramid lakes, which provide state water to the Castaic Lake Water Agency and Southern California's Metropolitan Water District, began in June for MTBE, said Dan Peterson, chief of environmental assessment for the State Water Project.
During the months of testing, MTBE was found in both recreational reservoirs, Peterson said. The additive enters the water supply through recreational vehicles such as powerboats and Jet Ski-like personal watercraft, he said.
"It's not surprising that we found levels there if you have Jet Skis and motorboats," Peterson said. "We find more of it in the top 3 feet (of the reservoirs). There's less at deeper depths."