Formaldehyde Labeled a Carcinogen

In doing so, the EPA adopted a far more lenient assessment of formaldehyde danger. Administration officials said the controversial change was justified by the "best available science."

Administration critics Tuesday characterized the international health group's action as a rebuke of the EPA's handling of the matter. An industry representative downplayed the international finding, noting that the reclassification of formaldehyde was not a finding of actual risk.

The World Health Organization panel, made up of 26 scientists from 10 countries, reviewed the latest literature and concluded that formaldehyde posed a greater hazard than previously thought.

"Based on this new information, the expert working group has determined that there is now sufficient evidence that formaldehyde causes nasopharyngeal cancer in humans, a rare cancer in developed countries," said a statement Tuesday from the agency's headquarters in Lyon, France. Nasopharyngeal refers to the area in the back of the mouth and nose.

The organization's previous evaluation of formaldehyde had concluded it was "probably carcinogenic." Review of the latest epidemiological studies "increased the overall weight of the evidence" about the toxic chemical, the expert panel said.

The scientists included in their assessment recent studies by the National Cancer Institute and the National Institute of Occupational Safety and Health showing that exposure to formaldehyde might also cause leukemia in humans. The panel concluded that evidence of such a link was "strong but not sufficient" to establish a causal relationship.

The administration adopted its less stringent formaldehyde risk assessment shortly after the leukemia studies were disclosed. The EPA wood products rule did not mention leukemia risk. White House and EPA officials said this was because the two U.S. studies and a third in England appeared contradictory and were not thoroughly reviewed.