Formaldehyde is a colorless gas used in the production of resins, wood products, plastics, fertilizers, and foam insulation. It also has utility as a textile finish, preservative, stabilizer, disinfectant, and antibacterial food additive. In solution as formalin, it has uses as a disinfectant, and the total number of products containing formaldehyde exceeds 3000, any of which may give off formaldehyde vapors. There is one poorly documented foreign report in which lower birth weights were said to be recorded among 446 females exposed to formaldehyde vapor at concentrations ranging from 1.2-3.6 ppm compared to 200 control women. In the absence of corroborating and better validated studies, this report is not included as being valid. Laboratory animal studies by the inhalational route have been limited to the rat, and their relevance to human exposures is unknown. Formaldehyde is one of the smallest organic human developmental toxicants. It is hydrophilic and is capable of participating in hydrogen bonding interactions as an acceptor.