Niobium has no known biological function. Some species of unicellular algae have been shown to accumulate the radionuclide ⁹⁵Nb (Morgan, 1961). Binding of niobium ions in solution by bacteria has also been reported (Engel, 1970; Ishii, 2004).

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Engel WB. Role of metallic ion concentrating microorganisms in the corrosion of metals. Proc Conf Nat Ass Corros Eng, 25th. 1970:588-96.

Ishii N, Tagami K, Enomoto S, Uchida S. Influence of microorganisms on the behavior of technetium and other elements in paddy soil surface water. J Environ Radioact. 2004;77:369-80.

Morgan GB. Absorption of radioisotopes by certain microorganisms. Quart J Florida Acad Sci. 1961;24:94-100.