Humic material/substances pollutant associations

In addition to complexing metals in the aqueous phase, humic materials can also remove metals and radionuclides contained within the mineral matrix (18). The factors that control this behavior are not well understood however, it has direct implications on waste storage and containment strategies. The binding of organic and inorganic contaminants to humic substances is known to alter their bioavailability (41). Organic contaminants that are associated with humic substances are essentially unavailable for uptake by biota. In most cases studied, toxic metals associated with humic materials also have reduced uptake. With the new focus on bioremediation of polluted are as, the effect of the association of pollutants with humic materials on their phytotoxic properties must be considered, particularly for bound metals and radionuclides. 

Perdue, E. M. (1983). Association of organic pollutants with humic substances partitioning equilibria and hydrolysis constants. In Aquatic and Terrestrial Humic Materials (R. F. Christman and E. T. Gjessing, eds.). Ann Arbor Science, Ann Arbor, MI, pp. 441-460. 

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