Physicochemical characterization of the pelotherapeutic and balneotherapeutic clayey soils and natural spring water at Isinuka traditional healing spa in the Eastern Cape Province of South Africa.

Isinuka Springs at Port St Johns in the Eastern Cape Province of South Africa is a traditional spa sacred to the AmaMpondo tribe of the Xhosa speaking people. The bathing pond is considered to have healing powers both spiritually and therapeutically. Hundreds of people flock into the spiritual pond every weekend for both recreational and its spiritual healing power. In this study, we present the metal concentrations of the bathing pond (sediments and water samples), the hole drinking water as well as sediments from a cave situated at the bottom of the hill harbouring the bathing pond. Our results show that the geophagic clays from the cave and bathing pond has elevated concentrations of earth metals (up to 134,506 mg kg for calcium), trace metals (up to 36,272 mg kg for iron) and toxic metals (up to 25 mg kg for lead). The levels of both essential and toxic metals in the drinking water were above the recommended daily limits except for zinc and copper. Aluminium, a metal with antibacterial activity was as high as 71,792 mg kg in pond sediments. Even though the results show elevated concentrations especially for toxic metals, the study observes that the spa remains limited in potential for metal toxipathy because the frequency of contact with the pond is minimal estimated at once a week by traditional healers and once a month for locals while visitors from other parts of the province rarely come back.