Volcanoes chloromethane

VLDL, heart disease and, 1090-1091 Volcano, chloromethane from, 332 Vulcanization, 245-246, 499... 

The chloride anion is a major species in the oceans and plays an essential role in biochemistry. Compounds containing carbon-chlorine bonds occur much less frequently in nature. Volcanos emit some halocarbons, and marine algae generate chloromethane. Other marine species produce toxic organohalogen molecules that protect them from predators. Nevertheless, organic chlorine compounds are uncommon, and consequently there are few mechanisms that degrade them. 

Chloromethane (CH3CI) is produced by giant kelp and algae and also found in emissions from volcanoes such as Hawaii s Kilauea. Almost all of the atmospheric chloromethane results from these natural sources. 

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