The International Agency for Research on Cancer (IARC) recently concluded, based on human exposures in the workplace, that formaldehyde can cause nasopharyngeal cancer (cancer of the nose and throat). IARC also found
limited evidence that formaldehyde may cause other respiratory tract cancers, and a possible link with leukemia. Previously, the U.S. Environmental Protection Agency had classified formaldehyde as a “probable” human
carcinogen, based on studies of laboratory animals repeatedly exposed to high levels of formaldehyde.
When assessing formaldehyde for identification as a California Toxic AirContaminant, the ARB’s Scientific Review Panel concluded that, like other carcinogens, there is no level of exposure below which the risk of developing cancer is zero. Estimating Californians’ risk from current indoor levels of formaldehyde is complex. As an approximation, if the California population were exposed to current, average indoor levels of formaldehyde over a lifetime, ARB staff estimate that about 4000 excess cases of cancer would be expected to develop, or about 115 excess cases of cancer per million people
exposed. Reducing your exposure to formaldehyde will help reduce your individual risk.