Pigs in diving suits reveal carbon tetrafluoride could curb the bends

Duke researchers tested carbon tetrafluoride (CF4) as part of a breathing-gas mix in 40 pigs under simulated deep dives in a hyperbaric tank. The pigs switched to CF4 for the last 10 minutes of the dive had fewer decompression sickness signs and no deaths, while the control group breathing heliox faced severe symptoms and high mortality. CF4 is less soluble than helium, slowing inert-gas uptake and bubble formation, suggesting a potential safer gas mix for deep dives. However, the authors caution that translating this to humans is not immediate due to cost and safety considerations, and likely limits its use to commercial or military diving. The study was published in Proceedings of the National Academy of Sciences (PNAS).