CHARLESTON, W.Va. -- State health officials late Wednesday advised pregnant women who get their water from West Virginia American Water's Charleston-based system to drink only bottled water until levels of the chemical "Crude MCHM" are not detected at any level.
At about 8 p.m., the West Virginia Department of Health and Human Resources' Bureau for Public Health issued a one-page "Water Advisory for Pregnant Women." The advisory recommended the step "out of an abundance of caution" and based it on consultations with the federal Centers for Disease Control and Prevention.
Lawrence Messina, a spokesman for the state Department of Military Affairs and Public Safety, said the government plans to notify the public when the level in the WVAW system drops to zero and the advisory for pregnant women is lifted.
State officials also released a one-page letter to DHHR Secretary Karen Bowling in which CDC Director Dr. Thomas Frieden cited "limited availability of data" on the chemical released into the Elk River drinking water supply by Freedom Industries a week ago.
In the letter, Frieden said the CDC's previous guidance concentrations of the chemical below 1 part per million are "a protective level to prevent adverse health effects."
The advisory for pregnant women comes after state officials have said little about how the 1 part-per-million figure was derived, and the CDC has refused repeated requests for interviews on the matter.
Reached at his home Wednesday night, Frieden refused to answer questions from a Charleston Gazette reporter.
"I'll give you the number of the CDC press office. This is a private number," Frieden said. "If you'd like to reach the CDC, you need to go through the press office."
Later, senior CDC press officer Tom Skinner said, "There's not a lot of data that we have with this particular chemical as the letter alludes to. We're basing our calculations on the limited data and experience that we have on this.
"That also involves data from animals and people, so I think that's why the letter is worded the way that it is," Skinner said late Wednesday night.
In his letter to Bowling, Frieden defended the CDC's methods, noting that "there are few studies on this specialized chemical" and that agency officials "used the available information."
"These calculations use safety factors to take into account the differences between animals and people, and to consider possible effects on specialized populations," Frieden wrote. "An additional safety factor was applied to account for the limited availability of data."