What Is Tungsten?

USGS estimates that 60% of the tungsten consumed in the United States was used in cemented carbide parts for cutting and wear-resistant applications, primarily in construction, metalworking, mining and oil and gas drilling, with the remainder used in alloys and specialty steels, electrodes, filaments, wires and other components, and chemicals. It says tungsten has not been mined commercially in the United States since 2015.

ATSDR says exposure to very low levels of tungsten may occur by breathing air, eating food or drinking water that contains it, that no specific health effects have been associated with exposure to tungsten in humans, and that exposure to high levels of tungsten is unlikely. It reports that NIOSH recommends an exposure limit of 5 mg/m3, averaged over a 10-hour period, for tungsten and insoluble tungsten compounds in air.

In its Volume 131 monographs, IARC classified weapons-grade tungsten alloy containing nickel and cobalt as possibly carcinogenic to humans (Group 2B), based on sufficient evidence of cancer in experimental animals. A 2018 case series in Respiratory Medicine Case Reports describes hard metal pneumoconiosis as a rare and serious occupational lung disease that occurs after inhaling the hard metals tungsten carbide and cobalt, with the greatest exposures in mining, the cemented tungsten carbide industry, alloy production, and grinding and sharpening of steel tools with these abrasives.