August 1999 Update Air pollution contributes to lung disease, including respiratory tract infections, asthma, and lung cancer. Lung disease claims close to 335,000 lives in America every year and is the third leading cause of death in the United States. Over the last decade, the death rate for lung disease has risen faster than for almost any other major disease. Poor indoor air quality can cause or contribute to the development of chronic respiratory diseases such as asthma and hypersensitivity pneumonitis. In addition, it can cause headaches, dry eyes, nasal congestion, nausea and fatigue. People who already have respiratory diseases are at greater risk. Biological pollutants, including molds, bacteria, viruses, pollen, dust mites, and animal dander promote poor indoor air quality and may be a major cause of days lost from work and school. In office buildings, heating, cooling, and ventilation systems are frequent sources of biological substances that are inhaled, leading to breathing problems. To help prevent growth of mold when humidity is high, make sure bathrooms, kitchens and basements have good air circulation and are cleaned often. The basement in particular may need a dehumidifier. And remember, the water in the dehumidifier must be emptied and the container cleaned often to prevent forming mildew. An estimated one out of every 15 homes in the United States has radon levels above 4pci/L, the U. S. Environmental Protection Agency-recommended action level. Radon, a naturally occurring gas, can enter the home through cracks in the foundation floor and walls, drains, and other openings. Indoor radon exposure is estimated to be the second leading cause of lung cancer. A recent report by the National Research Council estimates that radon is responsible for between 15,000 and 21,000 lung cancer deaths each year in the United States. Environmental tobacco smoke (ETS) also called "secondhand smoke," a major indoor air pollutant, contains about 4,000 chemicals, including 200 known poisons, such as formaldehyde and carbon monoxide, as well as 43 carcinogens. ETS causes an estimated 3,000 lung cancer deaths and 35,000 to 50,000 heart disease deaths in non-smokers, as well as 150,000 to 300,000 cases of lower respiratory tract infections in children under 18 months of age each year. Formaldehyde is a common chemical, found primarily in adhesive or bonding agents for many materials found in households and offices, including carpets, upholstery, particle board, and plywood paneling. The release of formaldehyde into the air may cause health problems, such as coughing; eye, nose, and throat irritation; skin rashes, headaches, and dizziness. Asbestos is the name given to a group of microscopic mineral fibers that are flexible and durable and will not burn. Asbestos fibers are light and small enough to remain airborne; they can be inhaled into the lungs and can cause asbestosis (scarring of the lung tissue), lung cancer and mesothelioma, a relatively uncommon cancer of the lining of the lung or abdominal cavity. Many asbestos products are found in the home, including roofing and flooring materials, wall and pipe insulation, spackling compounds, cement, coating materials, heating equipment, and acoustic insulation. These products are a potential problem indoors only if the asbestos-containing material is disturbed and becomes airborne, or when it disintegrates with age. Heating systems and other home appliances using gas, fuel, or wood, can produce several combustion products, of which the most dangerous are carbon monoxide (CO) and nitrogen dioxide (NO2). Fuel burning stoves, furnaces, fireplaces, heaters, water heaters, and dryers are all combustion appliances. Carbon monoxide is an odorless, colorless gas that interferes with the distribution of oxygen to the body. Depending on the amount inhaled, this gas can impede coordination, worsen cardiovascular conditions, and produce fatigue, headache, confusion, nausea, and dizziness. Very high levels can cause death. Nitrogen dioxide is a colorless, odorless gas that irritates the mucous membranes in the eye, nose and throat and causes shortness of breath after exposure to high concentrations. Prolonged exposure to high levels of this gas can damage respiratory tissue and may lead to chronic bronchitis. Household cleaning agents, personal care products, pesticides, paints, hobby products, and solvents may be sources of hundreds of potentially harmful chemicals. Such components in many household and personal care products can cause dizziness, nausea, allergic reactions, eye/skin/respiratory tract irritation, and cancer. Bron: American Lung Association