There are global variations on this asphyxiation-by-carbon-dioxide phenomenon. Rather infamously, back in 1986, Cameroon’s volcanic Lake Nyos – which had accumulated and trapped centuries’ worth of dissolved carbon dioxide gas within its waters – unleashed its colorless, odorless payload all at once. The cascading gas wiped out every living thing in its path, including more than 1,700 people.
Although it’s not yet certain what triggered the sudden overturning of the lake and the subsequent release of gas, it could easily happen again – which is why authorities are artificially degassing it to make sure that it can’t.
A similar, but less deadly event took place a couple of years earlier at Cameroon's Lake Monoun. Although these so-called "limnic eruptions" are far more sudden and catastrophic compared to the perpetual emissions at Plutonium, both speak to the lethal power of geologic CO2.
Rather curiously, traditional villagers living near Lake Monoun claimed that evil spirits periodically escaped the lake in order to kill people.
“More than 2,000 years ago, these phenomena could not be explained scientifically but only by the imagination of supernatural forces from Hadean depths or well-meaning gods,” the team’s study concludes. Times may have changed, but the power of (geological) hell clearly still inspires fear in the hearts of many.