Suicide by inhaling hydrogen sulfide has become a social phenomenon in Japan. Police say that some 300 people may have killed themselves this way in the past year, including at least 70 from January to April. Even during the first week of May, suicides by inhaling the gas continued.
Neighbors of those who choose to kill themselves with the gas are also at risk. Although hydrogen sulfide smells like a rotten egg, it has no color and being heavier than air it can easily accumulate. When a junior high school girl student killed herself with the gas on April 23 in Konan, Kochi Prefecture, about 120 neighbors were evacuated and 14 of them were hospitalized.
Some people who decide to commit suicide this way are aware of the danger to others and even post notices warning neighbors that hydrogen sulfide is being produced. But such notices do not always work.