There are three different types of indoor air pollutants.
Particulates: dust, pollen, dust mites, animal dander, carpet fibers, and lint.
Micro-organisms: mold, influenza, fungi, viruses, bacteria, and germs.
Toxins (gases): benzene chemical vapors, formaldehyde, carbon monoxide, paint, pesticides, carpet fumes, pet odors, ozone, cleaning vapors, and smoke.