Air Quality & Outdoor Pollution Make an Appointment Ask a Question Search Conditions What is Air Pollution? Air pollution is caused by gases, dust particles, fumes, smoke and odors. Pollution can injure the lungs, cause diseases to develop and make symptoms of allergies, asthma, COPD and other diseases worse. Air Quality Reports Many cities across the country offer daily ozone and air quality forecasts to help you know when the air quality is low, using the Air Quality Index ratings below. COLORADO AIR QUALITY NATIONAL AIR QUALITY