Hydrochemical Characteristics of Surface Waters and Their Relationships to the Kashin–Beck Disease in Longzi County, Tibet

Although previous studies have been reported between the Kashin–Beck Disease (KBD) epidemic and the hydrochemical characteristics of surface waters, the etiology of the disease remains unclear. In the present study, we investigated the relationship between the KBD and the environment by comprehensively examining the hydrochemical characteristics of surface waters in Longzi County, Tibet, and the spatial incidence of the disease. Results show that, the pH (mean = 7.27±0.30), TH (mean = 57.08±45.74 mg L–1), and TDS (mean = 67.56±44.00 mg L–1) of surface waters in KBD endemic areas are lower than for those in the non-KBD endemic areas (means of pH = 7.49±0.30; TH = 262.06±123.29 mg L–1; TDS = 253.25±100.39 mg L–1). These results suggest that long-term consumption of low TDS, essential trace elements (e.g., nickel, cobalt, iron, selenium, zinc, molybdenum, and iodine) deficient, and potential toxic elements (such as arsenic) enriched waters by humans likely causes the KBD. Environmental factors such as the geology and geomorphology may produce biogeochemical imbalance, geomorphic, vegetation types and local climatic conditions may have significant impact on food fungi toxin poisoning and water organic compound poisoning, and these are also important in the KBD occurrence.