Tungsten

CAS ID #: 7440-33-7

Affected Organ Systems: Respiratory (From the Nose to the Lungs)

Cancer Classification: EPA: Not evaluated. IARC: Not evaluated. NTP: Not evaluated

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Chemical Classification: Inorganic substances

Summary: Tungsten is a naturally occurring element. It occurs in rocks and minerals combined with other chemicals, but never as a pure metal. Elemental tungsten is a white to steel gray metal (depending on the purity) that can be used in pure form or mixed with other metals to make alloys. Tungsten alloys tend to be strong and flexible, resist wear, and conduct electricity well. Tungsten is used in products such as x-ray tubes, light bulbs, high-speed tools, welding electrodes, turbine blades, golf clubs, darts, fishing weights, gyroscope wheels, phonograph needles, bullets, and armor penetrators. Tungsten is also used as a catalyst to speed up chemical reactions. Chemical compounds of tungsten are used for many purposes. Cemented tungsten carbide is a hard substance used to make grinding wheels and cutting or forming tools. Other tungsten compounds are used in ceramic pigments, as fire retardant coatings for fabrics, and as color-resistant dyes for fabrics.