Under certain conditions of use, ion generators and other air purifiers that generate ozone can produce levels of this lung irritant significantly above levels considered harmful to human health. A small percentage of air purifiers claiming a health benefit may be regulated by the FDA as a medical device. Many manufacturers often use ionizing technology in their air purifiers to increase the characteristics of their machines and increase the price of the system. Although this may seem logical, evidence against the effects of this technology can do a disservice to the company. As more information is disseminated and presented to the public about the potential risks of air ionizers, consumers will be better informed before making a purchase decision, and they are likely to be aware of and avoid these potentially hazardous ionizing air systems.
Studies have also shown that ionizers can worsen allergies and asthma in some cases. Not only does ozone become a lung irritant, but remaining allergens and dust can trigger symptoms. Negative ions occur naturally, near waterfalls or after rain. These negative ions can even positively affect humans, animals and the environment because they create oases of clean air. However, ionic air filters are not always so benign.
When released into indoor air and inhaled, ozone is a powerful lung irritant that exacerbates allergies and asthma. Ionic air purifiers not only produce ozone as an undesirable by-product, but they are not even particularly effective in removing other pollutants from the air. Ionizer air purifiers are generally safe because ionizers aren't energized enough to be harmful to you. These ionizers turn on for 8 hours every day, and I have a Therapure TPP300D with UV+ ionizer that turns on for 8 hours in my living room. Despite conflicting data surrounding the safety of ionizers, I usually keep my ionizer option turned off. Air ionizers are designed to help provide cleaner air and they do so through the use of ionized particles.
However, to get rid of the dangers of second and third hand smoking from my roommate, I now plan to keep my ionizer turned on only for 30-40 minutes when no one is in the room, and then turn off the ionizer before anyone comes in.