Source:http://linkedlifedata.com/resource/umls/id/C0025617
MSH: The simplest saturated hydrocarbon. It is a colorless, flammable gas, slightly soluble in water. It is one of the chief constituents of natural gas and is formed in the decomposition of organic matter. (Grant & Hackh's Chemical Dictionary, 5th ed),CSP: colorless, odorless, inflammable gas, CH4, produced by decomposition of organic matter, which may explode when mixed with air or oxygen; the first member of a homologous series of saturated hydrocarbons, including ethane, propane, and butane.