Frickel (sociology, Tulane U.) examines a scientists' social movement that became the study of genetic toxicology. As a group of scientists became aware that synthetic chemicals could change genetic structures, they became activists, developing a network of researchers and politicians, establishing funding, and publishing articles and books that came to define environmental health science. Frickel explains how researchers on mutations had to carefully differentiate those caused by synthetic chemicals, developing new methods of acquiring and analyzing data. The results were so alarming, and convincing, that the scientists were able to enlist the aid of others with expertise into a unique social movement based on evidence rather than mere emotional reaction; they then began to work within the political arena to inform those who made environmental policy. Appendices include a list of scientists interviewed in this study and a timeline of events from the beginnings of the movement in 1964 through 1976.