Hydrogen sulphide suspected in deaths of three at Japanese hot spring

Three men died Wednesday while working at popular hot spring in northern Japan, possibly due to toxic gas poisoning, a local fire official said. Two municipal workers from Senboku city in Akita prefecture and two contractors were at the snow-covered source of the volcanic hot spring to carry out maintenance, the official said. Rescue workers who arrived at the scene said the three were in a “state of cardiopulmonary arrest” – a term is used by first responders because only a doctor can certify death.

One of the city workers made an emergency call to report that the three others had collapsed. The three people were pulled from a hole… roughly two metres deep, possibly affected by hydrogen sulfide.

Japanese official

Hydrogen sulphide is a gas commonly found in volcanic hot water springs, the result of bacterium that grow in the absence of oxygen. Humans are able to tolerate low levels of hydrogen sulphide, but workers are usually equipped with detectors that sound an alarm as soon as the level is higher than 15 ppm. Extreme poisoning by hydrogen sulphide is often identified by checking the change in a victim’s pocket: copper coins will become discoloured when exposed to the gas.

Science