From 1954 to 1963, numerous scientists engaged in a public debate over the possible hazards from radioactive fallout from nuclear weapons testing. Nobel laureate Linus Pauling, a California Institute of Technology chemist, was one of the most prominent. His scientific papers relating to the fallout debate reveal many of the scientific, social and political issues involved in the controversy. Although the public controversy ended after the signing of the 1963 Limited Test Ban Treaty, many of the scientific questions about the possible hazards of low-level radiation remain under debate within the scientific community. Moreover, the fallout debate was a prototype of current controversies over environmental and public-health hazards.