[citation needed] Burk joined the Department of Agriculture in 1929 working in the Fixed Nitrogen Research Laboratory.

[10][11][better source needed] He and a coauthor published an analysis of cancer mortality in 10 cities that fluoridated the drinking water supply and 10 that didn't.

The paper was criticized for using overly broad grouping and making assumptions about variations in racial composition of cities.

[13] He also was an avid supporter of laetrile; an alleged cancer treatment regarded by the medical community as ineffective and potentially dangerous.

Dean Burk and Otto Heinrich Warburg discovered the photosynthesis I-quantum reaction that splits CO2 activated by respiration.

[16][17] For his techniques to distinguish between normal cells and those damaged by cancer, Dean Burk was awarded the Gerhard Domagk Prize in 1965.