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A 5.0 mM 1:1 uranium:citrate complex was prepared by combining equimolar amounts of citric acid and uranyl nitrate in deionized water. The pH of the sample was adjusted to 6.0 with 1N NAOH and the ionic strength to 0.1M with KCl. One hundred milliliters of the sample was transferred to 125 ml acid washed serum bottles and was incubated under 60 watt high output growth lights (Westinghouse, cool white #F24T12) at 25° C. Aerobic sample bottles were fitted with cotton plugs whereas the anaerobic samples were purged with nitrogen for about 20 minutes and then fitted with butyl rubber stoppers. Control samples were incubated in the dark. At periodic intervals samples were withdrawn and analyzed for pH, uranium and citric acid and its degradation products. Citric acid degradation products were identified by GC/MS. Under aerobic and anaerobic conditions, U(VI) citrate (aqueous) was photodegraded to yield a precipitate of U(VI) and citrate degradation products of acetic acid and CP2. Minor amounts of intermediate degradation products of citrate such as 3-oxoglutaric acid and a few unidentified products were also observed. Photodegradation of 1:1 uranium citrate complex under aerobic and anaerobic conditions is shown in FIG. 5. Photodegradation of uranium citrate complex was much more rapid and complete under aerobic conditions than under anaerobic conditions. Photodegradation of 1:1 uranium citrate complex showing the fate of uranium under aerobic conditions is presented in FIG. 6.