http://www.sbsun.com/breakingnews/ci_16660297BARSTOW - Don't drink the water.
That's what residents here were told Friday after unsafe perchlorate levels were discovered in local drinking water.
Golden State Water Company, which services Barstow and surrounding areas, issued the do not drink advisory after water tests at several sites revealed perchlorate levels exceeded six parts per billion, the maximum threshold considered safe.
The city of Barstow and the water company posted notices on its Web sites cautioning residents to avoid tap water.
"Barstow customers should not consume ice, water, beverage or formula prepared with tap water until further notice," the water company's statement said.
Boiling, freezing, filtering or letting water stand won't reduce perchlorate levels, the city's statement said. Boiling causes evaporation, which leads to concentrated perchlorate levels, the city statement said.
"Golden State Water Company is aggressively investigating our water system to determine the source of contamination so that it can be eliminated," the city statement said.
Perchlorate is an ingredient found in munitions, fireworks and rocket fuel that's known to affect human thyroid function. Explosives manufacturing in the local area is believed to be one way the chemical seeped into the Inland Empire groundwater supply.