Environmental exposure to thallium.

This paper reviews recent data and findings concerning the sources of thallium in the environment and its current environmental levels and exposures, particularly with respect to human exposure. Special emphasis is given to some recent cases of environmental thallium pollution that were recognized around several cement factories in the Federal Republic of Germany. Contaminated food grown in these areas gave rise to a significantly increased thallium exposure of the population living there. Recent studies show that the thallium level in human urine normally is below 1 micrograms/g creatinine and that the normal concentration range of thallium in human air is approximately 5-10 ng/g. These data allow to recognize even minor undue exposure to thallium in the work and general environment.