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Rare earth elements are often excluded in literature on the geochemistry and medical geology of serpentinitic geological systems. Exceptions are cases where they are used as geochemical or environmental tracers [13]. Yet, evidence shows that rare earth elements may undergo enrichment in serpentinites such as peridotite and dunite, as well as their ultramafic protoliths [32, 33]. The enrichment of rare earth elements have been attributed to various processes occurring during the hydrothermal transformation [32, 34]. First, a decline in the solubility of rare earth elements is attributed to a rise in the pH of hydrothermal solutions during the transition from acidic to alkaline conditions after interacting with alkaline ultramafic rocks. Second, the interactions between the ultramafic rocks and hydrothermal fluids/melts and sea water rich in rare earth elements promote enrichment of rare earth elements. Therefore, rare earth elements may occur in high concentrations in serpentinitic geological systems, where they may undergo simultaneous release and dissemination with other toxic contaminants. The dissemination of rare earth elements may occur via contaminated sediments, and solid wastes and wastewaters from mining and mineral processing [4, 10, 35].