Cadmium is also known to cause lung cancer in humans with long-term excessive exposure, and is suspected as a cause of prostate cancer. Cadmium has been shown clearly to induce cancers in laboratory animals. Either of these lung conditions can develop quickly or over a long period of time, and can be associated with relatively low exposure levels. Both conditions are potentially reversible if detected in early stages, but otherwise can progress rapidly or slowly to cause severe disability. Hard metal lung disease can be fatal.
Cobalt is a definite carcinogen in animals, and a suspected carcinogen in humans.
Contact dermatitis is common in saw filers and tool grinders. It also may be caused by skin irritation from coolants or by sensitization to other metals, such as nickel or chromium. The PELs are established at levels generally believed to ensure that nearly all workers will not suffer adverse health effects, even though they may be exposed daily to these levels in the workplace. Exposure levels above the PEL are considered potentially harmful, and the law requires that employers ensure that employees are never exposed to levels over the PELs. In 1993, Washington adopted detailed safety and health requirements for protecting employees from overexposure to cadmium.