THALLIUM POLLUTION ASSOCIATED WITH MINING OF THALLIUM DEPOSITS

Thallium pollution and poisoning have been found in mining districts o f thallium deposits as a result of introduction of thallium into surfa ce waters, soils, plants and human body owing to weathering and leachi ng of Tl-rich ores and rocks left in the open air. Waters in these min ing districts are divided into four types according to their Tl conten ts and concentration of less than 1 x 10(-9) is proposed as thallium s tandard for drinking water.