Iodine deficiency in soils and evaluation of its impact on thyroid gland diseases in areas subjected to contamination after the Chernobyl accident

• Spatial structure of modern I biogeochemical provinces is discussed.
• New method of evaluation of ecogeochemiсal situation was suggested.
• A risk map as a combination of technogenic and natural levels was created.
• The hypothesis about the universal character of the proposed method was formulated.

Geochemical and medical data on iodine deficiency and radioiodine “attack” after the Chernobyl accident were analyzed for the areas of Belarus Republic and Bryansk Oblast' of the Russian Federation. A concept that the spatial structure of modern iodine biogeochemical provinces is formed due to superposition of the natural and technogenic geochemical fields of this chemical element in biosphere is developed. The soil map, and the reconstructed radioiodine contamination have been used to evaluate soil iodine status and radioiodine attack capacity for particular settlements and regions and to create a combined health risk map for the Bryansk Oblast'. Obtained cartographic estimates were based on the real soil data and compared with medical data. The proposed approach helps to identify the areas of existing or possible negative biological effects with different health risk levels that might be helpful in eco-geochemical monitoring preventive steps and countermeasures.