Hemopyrrole and kryptopyrrole are absent from the urine of schizophrenics and normal persons.

We describe a method for detecting hemopyrrole and kryptopyrrole in urine, with a detection limit of 100 mug/liter (1 part in 10(7)). Urine is thoroughly extracted with methylene chloride and the extract is concentrated and examined by gas chromatography and gas chromatography-mass spectrometry. No hemopyrrole or kryptopyrrole could be detected in 52 samples, from 17 controls, 29 schizophrenics, and six persons with acute intermittent porphyria.