Chemical and radiological characterization of Peruíbe Black Mud

The Black Mud (PBM) extensively used for therapeutic treatments in the City of Peruíbe, Southwest Brazil, was characterized for its physicochemical properties, chemical constituent and mineralogical composition. Radiometric assay was done by determining its radioactive elements activity concentration and estimating the dose resulting from the mud application on the skin. It was determined that the PBM is a material mainly composed of silt–clayey and sand fine size particles. PBM may be characterized by being enriched in the elements Br, Cr, Sb, Se, and Zn and depleted in Ca, Rb, and Ta, related to the Upper Continental Crust. It has been found that the elements Fe, K, Cl, Mg, Ti, Ca, and P are enriched in the matured form, relative to the in natura form during the maturation process. Effective dose assessed for public members indicated that the therapeutic use of the mud poses no radiation risk to the individuals under therapeutic treatment.