Skip Navigation

Overview of the Respiratory System

Author(s): Nancy Moreno, PhD, Deanne Erdmann, MS, and Sonia Rahmati Clayton, PhD
Showing Results for: human Return to Presentation

Indoor Air Pollution and Asthma

Asthma is a lung disease that can causes inflammation and narrowing along the entire airway, from the nose to the lung. When the airway becomes swollen and inflamed, it grows narrower, allowing less air through to the lung tissue. This causes symptoms such as wheezing, coughing, chest tightness, and difficult breathing. 

Once considered a minor ailment impacting only a small portion of the population, asthma is now the most common chronic disorder of childhood, and it affects an estimated 6.2 million children in the US under the age of 18. Asthma runs in families, suggesting that genetic factors may play a role in the development of this disease. However, environmental factors also contribute to the disease process, and asthma can be triggered by a wide range of substances, called allergens.