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.
Helium, which is the second most abundant element in the universe (behind hydrogen) is about a quarter of all matter. It is a gas here on earth, and can only be liquefied if it is cooled to near absolute zero. It will not solidify, by the way. Outside earth, it is mostly found in stars where it is a plasma.