| Abstract: | Formaldehyde, a highly reactive gas with a pungent odor, is released from a variety of sources including urea-formaldehyde foam insulation, particle board, and plywood, as well as various combustion processes. Concentrations of formaldehyde associated with the presence of these products are higher indoors than outdoors. Under controlled conditions, formaldehyde causes eye and nasal irritation at air concentrations of 0.24 mg/m3 and above. Exposure, residential or occupational, has been associated with eye, nose, and throat irritation, coughing, wheezing, skin rashes, nausea, and other symptoms. Formaldehyde is also a sensitizer; Individuals who are allergic to formaldehyde, or who suffer from respiratory diseases, are likely to suffer the effects of formaldehyde at even lower concentrations. Based on its known metabolism, reactivity with DNA and other marcomolecules, as well as its mutagenic effects in many test systems, formaldehyde is thought to be genotoxic. Recent studies have indicated that formaldehyde is also a carcinogen in rats and probably in mice. Epidemiological studies to date have been inadequate to determine whether or not formaldehyde is a human carcinogen. Formaldehyde seems to be a direct acting carcinogen and it is likely to pose a carcinogenic risk to humans. |
