There are few things that can strike fear into a parent's heart more quickly than hearing that the water she has been giving her children to drink may contain dangerous levels of lead. But that is the situation that many D.C. parents are facing this morning after learning that the lead level studies that deemed their drinking water safe were based on data that is now being called "wildly incomplete."

According to the Washington Post, more than twice as many D.C. children as previously reported by federal and local health officials had high levels of lead in their blood amid the city's drinking water crisis, casting some serious doubt over the assurances given by city officials that the lead in tap water did not seriously harm children.

The new data was apparently uncovered by a House subcommittee investigating the Federal Centers for Disease Control and Prevention's (CDC) performance. Here's what they found:

In 2003, D.C. officials found tens of thousands of city homes with elevated lead in the water. But another whole year would go by before the public was alerted to the problem. Many D.C. residents began protecting themselves and their children by switching to filtered or bottled water.  

After D.C.'s lead problem became public in 2004, residents demanded studies to show whether or not their drinking water was safe. Analyzing data from previous years, the CDC found that in 2001 and 2002, the health department had collected results from 16,042 children and 15,755 children, respectively. But in 2003, results from only 9,229 children were on file. In other words, blood tests from thousands of city children were inexplicably missing from D.C. government files. This "incomplete" data showed that in 2003 there were 193 cases of children with elevated blood levels. In 2002, based on the testing of 15,755 children, there was 122 cases of children with elevated blood levels.  

And it was this data that was used to determine that lead in D.C.'s drinking water was not a significant problem. Using the partial data, the CDC, the nation's leading public health agency, and the D.C. Department of Health published a paper reporting that they were not finding a significant increase in children with dangerous lead levels.

The subcomittee requested the data directly from all D.C. labs and found a total of 486 cases of children with elevated blood levels compared with the 193 cases that the CDC had used to compile their report. These new figures are obviously quite alarming and have cast doubt on whether or not D.C.'s lead problem was really as insignificant as the CDC once thought. Stay tuned for more details from this House Subcomittee investigation.

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