Four linear furocoumarins (psoralen, bergapten, xanthotoxin, and isopimpinellin) were isolated from three varieties of healthy, commercially grown celery (Apium graveolens). Psoralen has not previously been reported to occur in celery. Combined levels of these photomutagenic and photocarcinogenic furocoumarins measured by normal-phase HPLC did not exceed 1.3 ppm in any of the celery varieties studied.