The regions in Armenia that were studied are biogeochemical provinces infiltrated by molybdenum. The content of molybdenum in the soils, waters, and living organisms in these provinces exceed the usual concentration of this element in other regions. Maximum quantities of molybdenum are found in slightly alkaline and neutral soils, as well as in soils the features of which are high contents of organic matter. It is in these soils that the molybdenum is most available for plants. Biochemical research resulted in findings of definite reactions on the part of animal organisms to an elevated content of molybdenum in the environment. An endemic disease that is similar in its symptoms to podagra develops in man within the limits of the Ankavan molybdenum province. The disease is accompanied by an increased blood molybdenum content, increased excretion from the organism of copper, increased xanthine oxidase activity, and an increase in blood uric acid content.