Bruce Nathan Ames (December 16, 1928 – October 5, 2024) was an American biochemist who was a professor of biochemistry and Molecular Biology Emeritus at the University of California, Berkeley, and was a senior scientist at Children's Hospital Oakland Research Institute (CHORI).

[3] The test revolutionized the field of toxicology and has played a crucial role in identifying numerous environmental and industrial carcinogens.

The ease with which Ames test allows widely used chemicals to be identified as possible carcinogens made him an early hero of environmentalism.

Previously, scientists tended to only look for positive or negative results without considering the magnitude of the effect, which meant that as more and more items were shown to be potentially mutagenic, there was no system for evaluating the relative dangers.

[15] He contended that most human genetic damage arises from essential micronutrients lacking in poor diets and the oxidation of DNA during normal metabolism, and that the most important environmental carcinogens may include some whose chief effect is to cause the chronic division of stem cells whereby the normal protective mechanisms of a cell become less effective.

Ames published results showing that many ordinary food products would be found carcinogenic according to the same criteria.