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.
As earlier said, helium occurs naturally in the universe in vast quantities, though on Earth it is relatively scarce. It is usually found in natural gas pockets in concentrations as high as 7 percent. When the planet formed, some 4.6 billion years ago, virtually no helium was present. Currently however, some 3,000 tones of this element are generated by Earth's crust every year.