COMPREHENSIVE GEOCHEMICAL RESEARCH OF THE ENVIRONMENTAL COMPONENTS IN ENDEMIC AREAS OF TRANSBAIKALIA

Abstract

The relevance of the research. Kashin–Beck disease, or Urov disease, is a classic example of endemic diseases. However, unlike other diseases, the cause of this one has not yet been determined. Currently, the scientists discuss more than 20 theories and hypotheses that explain its etiology and factors. The priority theory is the biogeochemical one, according to which the occurrence and history of the disease depends on the environmental factor (lack/excess of chemical elements or compounds). In this regard, the study of the environmental geochemistry in the area of Kashin–Beck disease is relevant. The main aim of the research is to assess the environmental components geochemical features in the territory of south-eastern Transbaikalia, area of Kashin–Beck disease distribution. Objects: environmental components – soil, bottom sediments, natural waters (surface, underground), drinking water salt sediments, core of tree rings, poplar leaves, lichen, moss, wormwood, potato, children’s hair, bones of domestic pig. Methods: Instrumental neutron activation analysis and inductively coupled plasma mass spectrometry for detection of chemical composition of environmental components; processing of the obtained data included normalization of chemical elements content relative to background values (the noosphere clarke, water of Lake Baikal) and calculation of indicative ratios. Results. The content of 26 (instrumental neutron activation analysis) and 62 (inductively coupled plasma mass spectrometry) chemical elements in 13 environmental components was studied. In the element composition of all the studied components, a regional geochemical association (Zn-Pb-Ba-Sb-As-Bi-Au) was identified, associated with the features of the regional metallogeny. For future research, the most informative components are natural waters, bone tissue, and children's hair. The most contrasting geochemical specialization of the environment is formed in settlements where, according to literature data, the maximum incidence of Kashin–Beck disease is observed. The disease etiology is multifactorial: natural conditions play an important role in the development of the disease, which leads to an imbalance in the element composition of the environmental components and, respectively, the human body.

Keywords

• kashin–beck disease
• urov disease
• south-eastern transbaikalia
• environmental geochemistry
• indicative ratios