Physico-chemical and geochemical characterization of Makirina Bay peloid mud and its evaluation for potential use in balneotherapy (N Dalmatia, Republic of Croatia)

Abstract

Makirina Bay peloid mud was analysed in the interest of determining its physico-chemical and geochemical characteristics in order to assess the suitability of peloid mud use for cosmetic and/or therapeutic purposes as material for mud wraps or baths. The properties of Makirina Bay peloid mud were compared with various raw geological materials (Dead Sea mud, the mud of ‘Capetta’, Lo Pagán lagoon sediments, and peloid mud from Morinje Bay) already applied or with potential to be used in various spa centres. Makirina Bay peloid mud is represented mostly by sandy silt and has a relatively high C_org content (5%) and cation exchange capacity (CEC) value (63.82 meq/100g). The mineral composition of peloid mud is dominated by dolomite and quartz, followed by illite/muscovite, aragonite, halite, calcite, and pyrite. The calculated contamination factor (CF) and index of geoaccumulation (I_geo) values for the majority of heavy metals showed that the peloid mud had a low contamination status. The highest CF and I_geo values were for lead, at 2.2 and 0.5 respectively, but the pollution load index value was < 1, indicating that no heavy metal contamination of the peloid mud exists. Geochemical analyses have shown the adequate comparability of Makirina Bay peloid mud with raw materials already successfully used in purposes related to wellness and therapy.