About 670,000 residents in Oregon have been told Friday to boil their drinking water after several tests found E. coli in water samples, the Portland Water Bureau said.
According to CNN, an alert sent to people who live in the city and nearby warned that they "should boil all tap water used for drinking, food preparation, tooth brushing and ice for at least one minute. Ice or any beverages prepared with un-boiled tap water on or after May 20 should be discarded."
"While we believe at this time that the potential health risk is relatively small, we take any contamination seriously and are taking every precaution to protect public health," bureau Administrator David Shaff said in a statement.
Between May 20 and May 23, samples taken three times "confirmed the presence of total coliform and E. coli in routine drinking water samples," the Portland Water Bureau said.
The alert was also received by Tigard and King City, Oregon, as well as parts of Gresham and other districts, NBC affiliate KGW reported. A full list of areas affected is available at KGW com.
Most types of E. coli, a bacterium, are harmless or cause brief diarrhea, according to the Mayo Clinic. According to NBC News, abdominal cramps, bloody diarrhea and vomiting can be caused through some strains.
After investigators determine that the water system is clean of contamination through surveillance sampling, customers will be notified when they no longer have to boil their water, Fox News reported.
This is the second water problem in two months for Portland. In April, the Portland Water Bureau diverted nearly 36 million gallons of water from a reservoir after officials feared it was tainted by a teenager's urine.
The boil water advisory is issued to about 670,000 customers in the Portland Water Bureau and the Burlington, City of Gresham (north of Interstate 84), Lake Grove, Lorna Portland Water, Palatine Hill, Rockwood, Tigard Water Service Area (including Durham, King City and Bull Mountain), Valley View and West Slope Water Districts.
