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.
Approximately 99% of the helium produced on Earth is the result of the alpha decay of underground deposits of minerals containing uranium or thorium. The helium is brought to the surface as a byproduct of natural gas production.