Particles in the air from many sources cause these lung problems. These sources include factories, smokestacks, exhaust, fires, mining, construction, and agriculture. The smaller the particles are, the more damage they can do to the lungs. Smaller particles are easily inhaled deep into the lungs. There, they are absorbed into the body instead of being coughed out. Certain types of jobs put you at greater risk for this than others. For instance, working in a car garage or textile factory can expose you to unsafe chemicals, dusts, and fibers.

Most work-related lung diseases are caused by repeated, long-term exposure. But even a severe, single exposure to an unsafe agent can damage the lungs.

Smoking can make this condition worse.

Chronic obstructive pulmonary disease (COPD) is a progressive, irreversible inflammatory disease in your lungs that makes it hard to breathe. Common symptoms include a chronic cough, wheezing, production of phlegm, shortness of breath, and a feeling of tightness in your chest, though these symptoms may not be noticeable until you're in the later stages of the disease. COPD is not curable, but it's a preventable and treatable illness. The earlier you start treatment, the better your prognosis.

COPD is the third-leading cause of death in the United States, preceded by only heart disease and cancer. It predominantly occurs in people over 40 years of age and affects more than 11 million Americans. However, millions of adults have evidence of impaired lung function, indicating that there is a high probability of under-diagnosis.

Interstitial lung disease is a general category that includes many different lung conditions. All interstitial lung diseases affect the interstitium, a part of the lungs' anatomic structure.

The interstitium is a lace-like network of tissue that extends throughout both lungs. The interstitium provides support to the lungs' microscopic air sacs (alveoli). Tiny blood vessels travel through the interstitium, allowing gas exchange between blood and the air in the lungs. Normally, the interstitium is so thin it can't be seen on chest X-rays or CT scans.

Interstitial lung disease (ILD) is a group of lung disorders in which the lung tissues become inflamed and then damaged.

Interstitial lung disease can be caused by long-term exposure to hazardous materials, such as asbestos. Some types of autoimmune diseases, such as rheumatoid arthritis, also can cause interstitial lung disease. In some cases, however, the causes remain unknown.

Once lung scarring occurs, it's generally irreversible. Medications may slow the damage of interstitial lung disease, but many people never regain full use of their lungs. Lung transplant is an option for some people who have interstitial lung disease.

Tuberculosis is spread through the air when people who have active TB in their lungs cough, spit, speak, or sneeze. People with latent TB do not spread the disease. Active infection occurs more often in people with HIV/AIDS and in those who smoke. Diagnosis of active TB is based on chest X-rays, as well as microscopic examination and culture of body fluids. Diagnosis of latent TB relies on the tuberculin skin test (TST) or blood tests.

Prevention of TB involves screening those at high risk, early detection and treatment of cases, and vaccination with the bacillus Calmette-Guérin (BCG) vaccine. Those at high risk include household, workplace, and social contacts of people with active TB. Treatment requires the use of multiple antibiotics over a long period of time. Antibiotic resistance is a growing problem with increasing rates of multiple drug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB).