Tungsten carbide-cobalt (WC-Co) is a so-called hard metal which is characterised by an extraordinary hardness and wear resistance. Hard metals are mainly used in the production of tools for milling, drilling and pressing/punching processes. In addition surgical instruments are made of tungsten carbide-cobalt and the best-known product is the rotating balls used in ball point pens.
Tungsten carbide-cobalt is produced from tungsten carbide powder to which metallic cobalt is added. Humans mainly get in contact with tungsten carbide-cobalt particles when handling the powdered form or during the grinding of workpieces. These released (nano)particles can then be taken up through the skin or via inhalation. Protection measures for workers handling these materials are mandatory at the workplace and include the use of respiratory protection masks and the installation of suction exhaust pipes. Within the finished processed workpiece tungsten carbide-cobalt particles are rigidly bound and no nanoparticles are being released during normal usage preventing uptake by the human body.
Tungsten carbide-cobalt is a toxic substance regardless of the size of the particles. The toxic effects are caused by the percentage of cobalt within the material. Tungsten carbide-cobalt is classified as probably carcinogenic and can cause a lung disease known as "Hard metal disease" in exposed workers. Nowadays this disease occurs only rarely since various protection measures and regulations have been put into place when handling this material at the workplace. Users are safe when handling finished workpieces containing tungsten carbide-cobalt nanoparticles since there is no particle release from these products. Modern factories producing this material are obliged to have filter facilities installed to prevent an environmental release of these materials. All waste products are collected and disposed of as hazardous waste.