# What makes mercury vapors so harmful?

I just read an experiment in which mercury has to be heated and in the same experiment there was a note warning not to inhale mercury vapors as they are very harmful.

I just can't get the point that why are mercury vapors harmful.

• Did you read wikipedia article on mercury poisoning? – permeakra Jun 30 '14 at 8:37

Mercury poisoning (also known as hydrargyria or mercurialism) is type of metal poisoning and a medical condition caused by exposure to mercury or its compounds. Mercury (chemical symbol $\ce{Hg}$) is a heavy metal occurring in several forms, all of which can produce toxic effects in high enough doses. Its zero oxidation state $\ce{Hg^0}$ exists as vapour or as liquid metal, its mercurous state $\ce{Hg2^{2+}}$ exists as inorganic salts, and its mercuric state $\ce{Hg^{2+}}$ may form either inorganic salts or organo-mercury compounds; the three groups vary in effects. Toxic effects include damage to the brain, kidneys and lungs.