What is silicosis?
Preventing silicosis is very important if its effect is to be surmounted in our work sites.
Silicosis is a form of occupational lung disease caused by inhalation of crystalline silica dust, and is marked by inflammation and scarring in the form of nodular lesions in the upper lobes of the lungs.
Silicosis is due to deposition of fine respirable dust (less than 10 micrometers in diameter) containing crystalline silicon dioxide in the form of alpha-quartz, cristobalite, or tridymite in the lungs tissue.
Epidemiology of silicosis
Silicosis is the most common occupational lung disease worldwide; it occurs everywhere, but is especially common in developing countries. In the United States, it is estimated that between one and two million workers have had occupational exposure to crystalline silica dust and 59,000 of these workers will develop silicosis sometime in the course of their lives.
Over the past 4 decades, the number of people dying with silicosis in the United States has declined dramatically because of improved workplace protection, but it still accounts for potential life lost before age 65 years.
This epidemiology shows the necessity of preventing silicosis.
Types of silicosis
- Acute silicosis, which results from short-term exposure to very large amounts of silica. The lung become very inflamed and is filled with fluid, causing severe shortness of breath and a low blood oxygen level.
- Chronic silicosis, which results from long-term exposure (more than 20 years) to low amounts of silica dust. The silica dust causes swelling in the lungs and chest lymph nodes. This disease may cause people to have trouble breathing. This is the most common form of silicosis.
- Accelerated silicosis, which occurs after exposure to larger amounts of silica over a shorter period of time (5 to 15 years). Swelling in the lungs and symptoms occur faster than in simple silicosis.
Signs and symptoms of silicosis
The American lungs association highlights the signs and symptoms to include:
Cough: This is an early symptom and develops over time with exposure to silica that is inhaled.
In acute silicosis, you may experience fever and sharp chest pain along with breathing difficulty. These symptoms can come on suddenly.
In chronic silicosis, you may only have an abnormal chest X-ray in the beginning and then slowly develop a cough and breathing difficulty. More than a third of people with silicosis have phlegm production and cough. Chronic bronchitis-like symptoms may occur, and the lungs have additional sounds called wheezes and crackles. As extensive scarring progresses over time, you may see signs of chronic lung disease such as leg swelling, increased breathing rate, and bluish discoloration of the lips.
Symptoms of silicosis can appear from a few weeks to many years after exposure to silica dust. Symptoms typically worsen over time as scarring in the lungs occurs.
Treatment of silicosis
There is no specific treatment for silicosis. Removing the source of silica exposure is important to prevent the disease from getting worse. Silicosis patient is also advised to limiting exposure to irritants and quitting smoking.
People with silicosis are at high risk of developing tuberculosis (TB). Silica is believed to interfere with the body’s immune response to the bacteria that cause TB.
People with severe silicosis may need to have a lung transplant.
If you start developing the above symptoms related to silicosis, contact a medical professional for proper examination.
Medscape prescribed the following medical care for silicosis patient:
- Prevent further exposure to silica dust.
- Strongly advise patients to quit smoking and provide help in smoking cessation efforts.
- Immunize patients against influenza and pneumococcal pneumonia.
- Corticosteroids may be of benefit in acute silicosis. In chronic silicosis, they are unlikely to be of benefit, although pulmonary function improvement was noted in one study.
- Selectively in patients with very advanced disease without other comorbid conditions, lung transplantation may be an option.
- Experimental (unproven) approaches to treatment include whole-lung lavage, aluminum inhalation, and parenteral administration of polyvinyl pyridine N-oxide.
- Latent tuberculosis infection (ie, positive tuberculin skin test result without active disease) should be treated with isoniazid (see Medication). A 10-mm induration is considered a positive test result in this population.
- Active tuberculosis (ie,Mycobacterium tuberculosis identified in smear or culture) should be treated with appropriate multiple drugs (see Medication) according to the most recently established guidelines. 
- Complications (eg, airflow obstruction, cor pulmonale, respiratory failure), should they occur, should be treated appropriately.
Silicosis is better prevented than treated. In Preventing silicosis, adequate planing, monitoring of air quality and dust concentration in the workplace is essential.
Water sprays and wet cutting methods reduce the risk of silica exposure.
Workplaces should meet Occupational Safety and Health Administration (OSHA) standards. This includes proper ventilation. Employers can monitor air quality at worksites to ensure that there’s no excess silica in the air.
The Occupational Safety and Health Administration (OSHA) has set a permissible exposure limit for respirable silica of 10 mg/m3. The National Institute for Occupational Safety and Health (NIOSH) standard is a more stringent exposure limit of 0.05 mg/m3.
In addition to the primary prevention measures, secondary methods include monitoring workers with chest radiograph and spirometry to identify early disease and to stop further exposure to silica.
Workers can wear special masks called respirators to keep from inhaling silica. These masks may be marked for “abrasive blasting” use.