Environment: Overview

Formaldehyde is a naturally occurring substance in the environment made of carbon, hydrogen and oxygen. According to the U.S. Environmental Protection Agency, natural processes in the upper atmosphere may contribute up to 90 percent of the total formaldehyde in the environment (World Health Organization, International Programme on Chemical Safety, Concise International Chemical Assessment Document: Formaldehyde). Since formaldehyde is a by-product of combustion, cars and trucks emit formaldehyde, as does burning wood (EPA Office of Air Quality, National-Scale Air Toxics Assessment, SAB Review Draft, Table 4-8, 2001).

Formaldehyde does not accumulate in the environment, because it is broken down within a few hours by sunlight or by bacteria present in soil or water. Humans metabolize formaldehyde quickly, so it does not accumulate in the body.