Formalin

Formaldehyde is an organic compound with the formula CH₂O. It is the simplest aldehyde, hence its systematic namemethanal.

Formaldehyde is a colorless gas with a characteristic pungent odor. It is an important precursor to many other chemical compounds, especially for polymers. In 2005, annual world production of formaldehyde was estimated to be 23 million tonnes (50 billion pounds).^[4] Commercial solutions of formaldehyde in water, commonly called formalin, were formerly used as disinfectants and for preservation of biological specimens.

In view of its widespread use, toxicity and volatility, exposure to formaldehyde is a significant consideration for human health.^[5] On 10 June 2011, the US National Toxicology Program has described formaldehyde as "known to be a human carcinogen".