Why CDC Responded With ‘Lack of Urgency’ to Formaldehyde Warnings

The Centers for Disease Control study (PDF) sounded reassuring when it was made public in 2007. Hurricane Katrina survivors didn't have to worry about reports that there were harmful levels of formaldehyde in their trailers. The air was safe to breathe and the contamination would not reach a "level of concern" as long as they kept the windows open.

Today, senior CDC officials acknowledge that the study was based on a fundamental error.

An agency standard says that people exposed to as a little as 30 parts of formaldehyde per billion parts of air (ppb) for more than two weeks can suffer constricted airways, headaches and rashes. The trailers all measured above that level.

But the scientists who conducted the study used a much higher agency standard to evaluate the formaldehyde in the trailers: instead of 30 parts per billion, they said health dangers wouldn't occur until the substance reached 300 ppb, 10 times greater than the long-term standard. According to the CDC, people exposed to that amount for just a few hours can suffer respiratory problems and other ailments.

The story of the Katrina survivors and the trailers has been told many times in Congressional hearings and in the media. But it has been unclear until now why government officials continued reassuring residents the trailers were safe, at least a year after they should have been warning them to get out.

A reconstruction of how CDC and other government agencies handled the formaldehyde problem, drawn from documents, interviews and a new congressional report (PDF), suggests that top government officials were worried from the beginning about lawsuits by the people living in the trailers. Communications among government agencies broke down, so much so that the CDC wasn't aware that other government agencies were continuing to rely on a flawed study.

CDC’s reaction to the formaldehyde problem was “marred by scientific flaws, ineffective leadership, a sluggish response to inform trailer residents of the potential risks they faced, and a lack of urgency to actually remove them from harm’s way,” concludes the 40-page report, scheduled to be released this week by Democrats on the Science and Technology Committee’s subcommittee on investigations and oversight for the U.S. House of Representatives.

The report also chronicles the futile efforts of Christopher De Rosa, a senior CDC toxicologist, to warn top officials of another problem with the 2007 study: It failed to mention that formaldehyde can cause cancer.

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