It has been established that over a long period of exploitation of gold deposits in Eastern Transbaikalia the area occupied by technogenic formations now measures more than 4 thou ha of land. Most of the tailings of Eastern Transbaikalia date back to the 1930s–1950s. Their surface was, for the most part, not covered with a layer of binding materials for fixing. When designing them, no waterproofing of the bases and protective dams was foreseen. It is shown that among the technogenic formations of the worked-out gold deposits in Eastern Transbaikalia the tailing dump of the gold extraction plant of the Kariiskoe deposit presents the greatest environmental hazard. Its potential toxicity is characterized by the values of GER = 52 632. Dumps of gold recovery plants of the Klyuchevskoe (GER = 4166) and Ilinskoe (GER = 6617) deposits are less dangerous. It was found that the tailings of gold deposits in Eastern Transbaikalia contain from 0.35 to 1.79 g/t of gold. In the course of experimental studies on the leaching of elements from gold-bearing ores, a high mobility of As, Ca, Fe, Cu, Pb and Zn, and a lower mobility of Ni, Co, Cd, Bi and Sb was determined. Studies conducted by specialists of the Research Institute of Occupational Medicine and Human Ecology (Irkutsk) showed that residents of Balei, compared to residents of the cities of Chita and Nerchinsk with no mining enterprises, significantly more often have pathologies of the circulatory organs, pathological disorders of the organs of vision and hearing and diseases of the respiratory system.Keywords: tailings, toxic elements, leaching, public health, ecological problems, gold deposits.