Methanethiol is an organosulfur compound with the chemical formula CH3SH. It is a colorless gas with a distinctive putrid smell. It is a natural substance found in the blood, brain and feces of animals, as well as in plant tissues. It also occurs naturally in certain foods, such as some nuts and cheese. It is one of the chemical compounds responsible for bad breath and the smell of flatus. Methanethiol is the simplest thiol and is sometimes abbreviated as MeSH. It is very flammable.
Cylinder of methanethiol gas
Hydrogen sulfide is a chemical compound with the formula H2S. It is a colorless chalcogen-hydride gas, and is poisonous, corrosive, and flammable, with trace amounts in ambient atmosphere having a characteristic foul odor of rotten eggs. Swedish chemist Carl Wilhelm Scheele is credited with having discovered the chemical composition of purified hydrogen sulfide in 1777.
Deposit of sulfur on a rock, caused by volcanic gas
Sludge from a pond; the black color is due to metal sulfides
A hydrogen sulfide bloom (green) stretching for about 150km along the coast of Namibia. As oxygen-poor water reaches the coast, bacteria in the organic-matter rich sediment produce hydrogen sulfide, which is toxic to fish.
