Gamma Radiation (2008)

Gamma Radiation was being tested by Bruce Banner when he was exposed turning him into the Hulk.

Biography
Gamma Radiation was being used in-order to create another super-soldier like Steve Rogers. It was a massive failure, literally. Thus the Hulk was born.

The Incredible Hulk
Throughout The Incredible Hulk, Banner is constantly trying to erase the Gamma Radiation in his blood and fully suppress the Hulk in-order to live a normal life. He fails epically, literally after Emil Blonsky used his Gamma irradiated blood to become the Abomination and faught the Hulk.