THE TOXICITY OF ORALLY INGESTED ARSENIC, SELENIUM, TELLURIUM, VANADIUM AND MOLYBDENUM

¹ Department of Experiment Station Chemistry, South Dakota State College, Brookings

Albino rats were fed salts of arsenic, molybdenum, tellurium, vanadium and selenium at levels of 25 and 50 parts per million of the elements in their diets. Toxicity of the elements was determined by their effects upon the growth, food consumption, mortality, and hematopoietic system of the animals. Growth curves, food consumption mortality, and hemoglobin levels are shown in the charts and tables. The following conclusions were made: (a) The relative toxicity of the elements in the increasing order of their toxicity was as follows: arsenic (Na₂HAsO₃) molybdenum ((NH₄)₆Mo₇O₂₄) tellurium (Na₂TeO₄ and Na₂TeO₃) vanadium (NaVO₃) selenium (Na₂SeO₃ and Na₂SeO₄). At the 50 parts per million level arsenic and molybdenum were slightly toxic, tellurium and vanadium were moderately toxic, and selenium was very toxic. (c) Of the five elements considered selenium was the only one which caused a distinct disturbance of the hematopoietic system. (d) The rats receiving tellurium in their diets exhibited a loss of hair (alopecia).