Formaldehyde is probably most familiar as the active ingredient in the solution used to preserve insects and other biological specimens. This solution, called formalin, is a water solution containing 35 to 40 percent formaldehyde by weight. Formaldehyde itself is a colorless gas which is the simplest member of the class of organic chemicals called aldehydes.
Formaldehyde was discovered in 1867 by August Wilhelm von Hofmann, a German chemist. It is made commercially by the oxidation of methanol (methyl alcohol). Formaldehyde is used for disinfecting, for embalming, and for preserving grains and vegetables. It is also used in the manufacture of pharmaceuticals, urea resins, and dyes. The plastics industry prepares Bakelite from formaldehyde and phenol.
Formaldehyde has a stifling odor and can irritate membranes of the eyes, nose, and throat. In addition, laboratory tests have shown that formaldehyde probably causes cancer. It boils at -21 °C.
