magine most of the people of an entire city coughing and wheezing, gasping for breath, unable to do anything except cough. Think about older people dying of exhaustion from the effort to breathe. Think about infants and small children with blue-tinged skin and lips, rolling and tossing with discomfort as they, too, struggle to breathe. Imagine air that feels thick enough to eat like soup, air that never seems to satisfy the need to breathe. This has happened over the years in many cities all over the world. The cause: air pollution.
Air pollution is a significant cause of asthma. Polluted air is air that contains any substance harmful to health. These can be gases such as sulfur dioxide, chemicals such as formaldehyde, or tiny bits and pieces of solid matter that float in the air. Most air pollution is man-made, but there are some pollutants, such as volcanic gases and debris, that occur from natural causes. Although some fires are man-made, a major natural cause of air pollution is forest fires that are most often caused by lightning. Burning of thousands of acres of woodland contributes to pollution by ash, gases, and tiny particles of other materials made airborne by air currents from the fire. These materials are very irritating to the mucous membranes of the respiratory tract and can trigger asthma, especially in people with twitchy lungs.