@wedivebc, CO2 is actually 25x more lipid soluble than nitrogen. Solubility doesn't tell the whole narcosis story though. The physiological effects of CO2 impart an even higher narcotic effect than the 25X solubility factor.
Carbon Dioxide, Narcosis, and Diving
CARBON DIOXIDE, NARCOSIS, AND DIVING BY JOHNNY E. BRIAN JR., M.D. Carbon dioxide (CO2) is the gaseous end product of the aerobic metabolism of oxygen. CO2 is highly soluble in body tissues, and readily diffuses from cells to blood, where circulation transports it to the lungs for elimination...
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