WHY THE WORLD IS running out of helium. “Scientists have warned that the world’s most commonly used inert gas is being depleted at an astonishing rate because of a law passed in the United States in 1996 which has effectively made helium too cheap to recycle. The law stipulates that the US National Helium Reserve, which is kept in a disused underground gas field near Amarillo, Texas – by far the biggest store of helium in the world – must all be sold off by 2015, irrespective of the market price.”