Physiological Effects Of Tungsten

Metallic tungsten and cationic tungsten are poorly absorbed through the digestive tract, but soluble tungstates can be absorbed via this route. Absorption via the respiratory tract and skin is unclear. After absorption, tungsten is primarily stored in bones, followed by the spleen, liver, and kidneys, where smaller amounts are found. Only trace amounts of tungsten are present in the blood, and it is mainly excreted in feces and urine. Inhaled tungsten is mainly distributed in the liver and kidneys, bones, and skeletal muscles.

Approximately 75% of ingested tungstate is excreted in urine. Injection of ¹⁸⁵W-tungstate into male, pregnant mice resulted in increased tungsten levels in bones, kidneys, liver, and spleen; these levels were then rapidly excreted in urine and feces. High concentrations of tungsten have also been observed in the thyroid gland, adrenal glands, pituitary gland, seminal vesicles of male mice, and follicles of female ovaries. Studies have found that tungsten can be transferred from mother to offspring, especially in late pregnancy, with significant deposition of compounds in the mother's bones, kidneys, spleen, and yolk sac epithelial cells, and in the offspring's bones.