Silicosis is occupational pneumoconiosis caused by inhalation of crystalline silicon dioxide. This disease is one of several well-described pulmonary complications associated with toxic exposures in the workplace, along with asbestosis, berylliosis, coal miner's lung, hard metal pneumoconiosis, among others.Symptoms of silicosis usually appear after many years of exposure. In early stages, symptoms are mild and include cough, sputum and progressive shortness of breath. As the scarring continues to worsen, the first real signs of a problem may be an abnormal chest X-ray and a slowly developing cough.