Allergens: Common sources of allergens in the environment include pollen from trees, grasses, and weeds; dust mites found in bedding, carpets, and upholstery; pet dander from cats, dogs, and other animals; mold spores present in damp environments; certain foods such as peanuts, shellfish, and dairy products; and insect venom from bees, wasps, and ants.
Irritants: Common sources of irritants include cigarette smoke, air pollution (e.g., vehicle emissions, industrial pollutants), strong odors (e.g., perfumes, cleaning agents), and chemicals found in household products, cosmetics, and personal care items.