Naphthalene is a naphthene (saturated hydrocarbons, C_nH_2n possessing a cyclic structure).

WHAT IS NAPHTHALENE?

Naphthalene is either a white solid or a liquid with a strong odor like mothballs.  It can also be a colourless crystal and is stable under ordinary conditions of use and storage.
It is used to make dyes, explosives, plastics, and lubricants.  Naphthalene is found naturally in crude oil and in coal tar.

Potential Health Effects:

Inhalation: Inhalation of dust or vapors can cause headache, nausea, vomiting, extensive sweating, and disorientation. The predominant reaction is delayed intravascular hemolysis with symptoms of anemia, fever, jaundice, and kidney or liver damage.

Ingestion: Toxic. Can cause headache, profuse perspiration, listlessness, dark urine, nausea, vomiting and disorientation. Intravascular hemolysis may produce coma with or without convulsions. Death may result from renal failure.
Skin Contact: Can irritate the skin and, on prolonged contact, may cause rashes and allergy. "Sensitized" individuals may suffer a severe dermatitis.
Eye Contact: Vapors and solid causes irritation, redness and pain. Very high exposures can damage the nerves of the eye.
Chronic Exposure: Has led to cataract formation in eyes. May cause skin allergy. 

On evaporation, naphthalene can end up in lakes, streams or soil. Naphthalene that seeps through soil into groundwater can remain unchanged for many years.  It is recommended that