An analysis of potential carcinogenic risk from formaldehyde.

Formaldehyde was recently shown to be carcinogenic in the nasal cavities of rats and mice following chronic inhalation at vapor concentrations which were cytotoxic. The epidemiological, physiological, and toxicological data on formaldehyde are evaluated as they pertain to the analysis of carcinogenic risk. It is concluded that humans are likely to be less susceptible than test rodents to potential carcinogenic effects and that the risk at low-level exposure would not be linearly related to that observed at the higher levels which were found to be carcinogenic in animals. Risk assessment procedures and risk management decisions should incorporate all of the relevant biological information, such as that discussed, rather than rely solely on a mathematical approach which is likely to yield inaccurate and misleading conclusions.