Formaldehyde (
IUPAC name
methanal) is a
chemical compound with the
formula CH2O. It is the simplest
aldehyde. Formaldehyde also exists as the cyclic trimer
trioxane and the polymer
paraformaldehyde. It exists in water as the hydrate H2C(OH)2. Aqueous solutions of formaldehyde are referred to as
formalin. "100%" formalin consists of a saturated solution of formaldehyde (this is about 40% by volume or 37% by mass) in water, with a small amount of
stabilizer, usually
methanol to limit
oxidation and
polymerization. A typical commercial grade formalin may contain 10-12% methanol in addition to metallic impurities like aluminium (3 ppm), iron (1 ppm) and copper (1 ppm).
Annual world production of formaldehyde (about 2005) was 21 million tonnes, or 46 billion pounds.
[1] [2] [3]
In view of its widespread use, toxicity, and volatility, exposure to formaldehyde is a significant consideration for human health.
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