We utilize an activated carbon filter. By itself, carbon is a highly absorbent material that can absorb thousands of different chemicals. Activated carbon is carbon with a slightly positive charge to it, which makes it even more absorbent to chemicals and contaminants. As your water passes over the charged carbon surface, the negative ions of the contaminants are attracted to the surface of the carbon granules. Activated carbon effectively removes volatile organic compounds (VOCs), pesticides, herbicides, chlorine, benzene, radon, cancer-causing chlorine byproducts such as THMs, and hundreds of other chemicals in tap water. Finally, here's the magic...activated carbon filters are NOT particularly effective at removing dissolved inorganic minerals/salts.