The second issue of Food Security is now published, and is free online. It documents some of the multiple causes of food insecurity.
Helium can be found in underground deposits in the earth. Helium can also be found in stars and other planets. The helium underground - and extracted from natural-gas - is a by-product of the natural radioactive decay of uranium, though is far too stable to be radioactive itself. It also occurs in very small amounts in the atmosphere.
The atmosphere around us only contains five parts per million of helium and that makes it too low to recover. Currently helium comes from natural gas and this seems to be the only economically viable source for the moment. It is captured with the natural gas in a porous rock formation years ago and when the natural gas is withdrawn the helium is also released from the natural gas reservoir. The natural gas â mainly methane â contains 0,5% or 5 000 ppm. This makes the recovery of helium more economical.