Odorous compounds in natural waters. Some sulfur compounds associated with blue-green algae.

Several odorous organic sulfur-containing compounds have been identified in cultures of blue-green algae using gas chromatographic techniques. The blue-green algae cultures were bacterially contaminated, and in all but one case the odorous sulfur compounds most probably resulted from bacterial putrefaction of th2 blue-green algal cells. The organism Microcystis flos-qucie, however, was shown to be capable of producing a natural gas odor, which was shown to be isopropyl mercaptan, during periods of active growth. Odorous sulfur compounds produced in decaying blue-green algal cultures and reservoir waters containing blue-green algal blooms included methyl mercaptan, dimethyl sulfide, isobutyl mercaptan, and n-butyl mercaptan.