Although silica (silicon dioxide) exists abundantly in nature, it is normally found within sand and rock where it cannot be inhaled. Yet when used in construction materials, silica dust is a common byproduct of construction activity, and may be inhaled by workers. (Due to exposure risks from sandblasting activities, silicosis is sometimes also called "sandblasting disease".) Exposure to silica dust is now considered as hazardous to human health as exposure to asbestos.
"Silica" is the common name for silicon dioxide, which is a compound formed from silicon and oxygen. Silica can exist in crystalline and noncrystalline forms. The most common natural form for silica is quartz, but it is also found in flint, agate, the sand found on beaches, and sandstone. Silica is also the main ingredient in glass.
Silicosis is a progressive, incurable disease of the lungs (a fibrogenic pneumoconiosis) caused by inhaling silica dust. In simple terms, the lungs are injured by inhaled silica dust resulting in the formation of scar tissue. Silicosis is characterized by discrete nodular pulmonary fibrosis and, as the disease progresses, by conglomerate fibrosis and respiratory impairment. People suffering from silicosis are also at increased risk of other pulmonary diseases, such as bronchitis and lung cancer.
The three forms of silicosis are:
Simple Chronic Silicosis - Silicosis resulting from long-term exposure to low amounts of silica dust. Common symptoms include breathlessness, similar to that displayed in other forms of chronic obstructive pulmonary disease (COPD). For this form of silicosis, exposure usually occurs over twenty or more years.
Accelerated Silicosis - Silicosis resulting from exposure to larger amounts of silica over a shorter period of time. Symptomology includes lung Inflammation and scarring. Symptoms progress faster in accelerated silicosis than in simple silicosis. For this form of silicosis, exposure usually occurs over five to fifteen years.
Acute Silicosis - Silicosis resulting from short-term exposure to very large amounts of silica dust. The lungs become inflamed and may fill with fluid, resulting in severe shortness of breath and low blood oxygen levels.
As silica dust is most frequently found in the production of glass and ceramics, mining, and construction settings, workers in mining, ship yards, foundry and construction settings are more likely to have been exposed to silica dust creating risk of developing silicosis. The probability of disease and, after onset, the severity of symptoms, correlates with the amount of time a worker is exposed to silica dust, and with the amounts to which the worker is exposed.
Litigation relating to silica dust exposure and silicosis emerges on a variety of theories. An attorney may allege that an employer is liable for failing to provide sufficient safety equipment or warnings about possible exposure to silica dust. Recovery against an employer often takes the form of a workers' compensation claim.
Many silicosis claims are directed at manufacturers of silica-based products, such as sandblasting compounds or other abrasives, with lawyers alleging that the products were not reasonably safe or did not meet industry or government health and safety standards. Manufacturers of safety equipment may find themselves subject to suit, if their products did not perform adequately resulting in worker exposure. Additional theories of liability are directed at the manufacturers of equipment, such as mining equipment, if their products resulted in worker exposure to unreasonable amounts of silica dust.