A comparative study of oxygen toxicity in vertebrates.

Survival time in conditions of hyperbaric oxygenation were measured in trout and eels in water, and in frog in water or in gas phase at various temperatures. In eel and trout, the gill surface is altered within 90 min at 15 ata pressure of oxygen. Survival times of the frog during hyperoxia in aquatic or gaseous conditions are only slightly different, in spite of the marked difference in the oxygen concentration of the two media. Oxygen toxicity is well correlated with the aerobic metabolic rate, (1) in a given species adapted to various temperatures; (2) in trout eel and frog observed at the same temperature. The differing O2 toxicities in homeothermic and poikilothermic animals are also related to the differences in metabolic activity.