Integrated Physicochemical Characterization of Techirghiol Sapropelic Mud and Its Relevance for Balneotherapy

Background: Sapropelic mud from Techirghiol Lake has been used therapeutically under medical supervision for more than 170 years; however, its comprehensive physicochemical characterization under application-relevant conditions remains insufficiently documented. This study aimed to evaluate the physicochemical properties, mineral and organic composition, ion-exchange capacity, and potential therapeutic mechanisms of Techirghiol sapropelic mud. Methods: Mud samples were analyzed using standardized physicochemical and analytical techniques to determine pH, water content, granulometry, mineral composition, organic fraction, and trace elements. Results: The results indicate that Techirghiol mud is a highly hydrated alkaline peloid characterized by a complex mineral–organic system. Major elements included sodium, calcium, and magnesium, while trace elements such as manganese, iron, and zinc were present in relevant concentrations. The organic fraction, composed of humic substances, lipids, and proteins, reflected advanced but incomplete humification processes. Conclusions: The findings demonstrate the complex physicochemical composition of Techirghiol sapropelic mud and provide a scientific basis for further studies regarding its properties and applications.