Exposure to silica dust can cause silicosis, a lung disease with three forms depending on exposure levels and duration. Simple chronic silicosis results from over 20 years of low silica exposure and causes lung inflammation. Accelerated silicosis occurs after 5-15 years of medium exposure and causes faster symptoms. Acute silicosis results from very high short term exposure and severe lung inflammation. Symptoms include cough, shortness of breath, and weight loss. Diagnosis involves exposure history, physical exam, chest x-rays, CT scans, pulmonary function tests, and blood tests.

1. SILICOSIS

2. Causes
• Silica is a common naturally occurring crystal. It is found in most rock
beds and forms dust during work with mining, quarrying, tunneling and
working with certain metallic minerals. Silica is a major component of
sand, so that people who work with glass and sand-blasters are also
exposed to this element.
• Three types of silicosis are presented:
• Simple chronic silicosis, which results from prolonged exposure (over 20
years) to low amounts of silica dust. This dust causes inflammation in the
lungs and chest lymph nodes. This disease can cause people to have
difficulty breathing and is the most common form of silicosis.
• Accelerated silicosis, which occurs after exposure to larger amounts of
silica over a shorter period (5-15 years). Inflammation of the lungs and
symptoms occur faster than in simple silicosis.
• Acute silicosis, which results from exposure to very large amounts of
silica short time. The lungs become very inflamed and may fill with fluid,
causing severe shortness of breath and low oxygen levels in the blood.

3. Symptoms
• Cough
• Shortness of breath
• Weight loss

4. Exams and Tests
• The doctor will take a medical history that includes many
questions about the work (past and present), hobbies and other
activities that may have exposed you to silica. The doctor will
also do a physical exam.
• Tests to confirm the diagnosis and rule out similar diseases
include:
• Chest x-rays
• CT scan of chest
• Pulmonary function tests
• Testing for TB
• Blood tests for connective tissue diseases

5. REFERENCES
• Cowie RL, Murray J, Becklake MR. Pneumoconioses and
other mineral dust-related diseases. In: Mason RJ,
Broaddus VC, Martin TR, et al, eds Murray and Nadel's
Textbook of Respiratory Medicine... 5th ed. Philadelphia,
Pa: Saunders Elsevier; 2010: chap 65.
• Tarlo SM. Occupational lung disease. In: Goldman L,
Schafer AI, eds Goldman's Cecil Medicine.. 24th ed.
Philadelphia, Pa: Saunders Elsevier; 2011: chap 93.