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Air Ionizer Dangers: Are Ionic Air Purifiers Safe?

Air ionizers are designed to help provide cleaner air and they do this by utilizing ionized particles. But a lot of questions tend to come with the use of air ionizers, one of the most common being…Are air ionizers dangerous?

The Short Answer: It depends on who you ask. Some critics believe that air ionizers give off dangerous levels of ozone which is not only harmful to the environment, but can be equally as hazardous to your health.

air ionizer dangers - air quality
Ozone exists in 2 levels of the atmosphere: in the stratosphere (good – protects us from the sun’s rays) and at the ground level (bad – toxic when breathed in)

When inhaled in high enough doses, ozone can have harmful effects– including damage to your lungs, chest pain, coughing, or shortness of breath.

Because of this concern, federally-mandated standards restrict the amount of ozone any air purifier can give off. These restrictions help to ensure that any potential ozone exposure remains at a safe level.

Air ionizers vs. Ionic air purifiers

First things first, let’s get our names straight. In the air purifier market, there are air ionizers and there are ionic air purifiers.

Rabbit Air Purifier Filters
The Rabbit Air MinusA2 uses 5 different filters and an ionizer as the last purification stage

What’s the difference?

Basically nothing.

These are two different ways to talk about the same technology, electrically charged molecules being used to help purify the air. In this guide, we’ll be calling them air ionizers– so let’s continue.

How do air ionizers work?

A typical air purifier would use fans or filters to help remove contaminants and purify the air. In the case of air ionizers, they rely on the use of electrically charged air molecules, or ions, to do the same job.

RELATED – See our full list of air purifier reviews.

Every room is filled with positively charged particles, which could be made up of dust, microbes, odors, airborne bacteria or illnesses, smoke or other allergens.

The job of an air ionizer is to release negatively charged particles that are then attracted and bond to the positively charged particles in the room.

how air ionizers work

When the ionized particles bond to the airborne particles, the joint union is then too heavy to float in the air and they fall to the ground. Once they’re no longer airborne, these particles can be vacuumed up, or dusted off of furniture and raised surfaces.

What are the benefits of air ionizers?

Negative ions produce a number of benefits in our natural environment.

Think of some of your favorite places. Maybe it’s the ocean, a serene waterfall or out in nature’s greenery.

Ionic particles produced by waterfalls

This short list here includes some of the natural environments with the highest levels of detected negative ions present

Air ionizers and their connection to negative ions can mean big benefits to your respiratory system and overall health. The use of negative ions in the air can have the following results:

  • Improved air quality through the removal of dust, allergens, pollen, pet dander, mold spores and other airborne bacteria.
  • Decreased exposure to airborne respiratory bacteria like colds, flu, and asthmatic triggers
  • Improved sleep and overall mood, according to a 2012 Italian study that looked at the evidence base for the benefits of negative ions in improving mood and treating mood disorders
  • Relief from seasonal or chronic depression— according to a study from Columbia University, negative ions can have as much of an effect as prescribed antidepressants

All this sound too good to be true?

Some people would say yes. Let’s talk about the potential negative side of negative ions.

What are the dangers of air ionizers?

So naturally occurring negative ions are highly beneficial and share all of the benefits listed above. In the case of air ionizers, these negative ions aren’t naturally occuring, but instead are created through a method called “electric-discharge”.

air ionizer dangers - air quality

During the process of electric discharge, the negative ions that are produced may give off ozone, which can be a very harmful and toxic gas.

What is ozone?

Ozone is a colorless gas that exists in two levels of our atmosphere– one is good and one can be not so good.

air ionizer dangers - oxygen vs. ozone
Oxygen has 2 oxygen atoms while ozone is made up of 3 oxygen atoms, making it toxic for humans to breathe.

On one level, it exists in the stratosphere (which is approximately 6-30 miles high) and helps to protect Earth from the sun’s harmful radiation.

On another level, it also exists at the ground level, which is the air we breathe. Ozone in this part of the atmosphere is not good.

Ever see those ozone alerts as you drive down the highway or on the nightly news?

These are generated to let you know that ozone levels at the ground level may be reaching unsafe levels.

High ozone levels in the air you’re breathing can have really nasty side effects including damage to your lungs, chest pain, coughing, or shortness of breath.

Do air ionizers emit ozone?

So the million dollar question- do air ionizers emit ozone?

In short, yes they do.

Any man-made high-energy particle, like a negatively charged ion can generate ozone as a by-product of the molecular reaction.

Anyone remember the Ionic Breeze from Sharper Image? This product was one of the first air ionizers that came out.

Initially it was widely popular, but trouble came when third-party review sites began to question not only the validity of the air purification system, but also the dangerous levels of ozone that it was emitting.

SHarper Image Ionic Breeze air ionizer advertisement -1999 - source: The Hustle

What resulted from this product was a class action lawsuit, bankruptcy for Sharper Image in 2008, and revised federally-mandated standards (under the Clean Air Act) that put limits on the amount of ozone that a machine like this could generate.

Under these new regulations, the US Food & Drug Administration (FDA) required that indoor medical devices can only produce a maximum of 50 ppb (parts per billion) of ozone.

For comparison, the National Institute of Occupational Safety and Health (HIOSH) advises that indoor ozone levels be no greater than 100 ppb.

Air ionizers today are often fitted with ozone sensors that help to monitor, suppress, and prevent high levels of ozone from sneaking out into the air you breath.

The Bottom Line

Deciding whether or not an air ionizer is right for you is a personal decision. There are certainly benefits to air ionization that be difficult to achieve with a standard air purifier, but with those benefits also come potential risks.

Ozone is a real threat to our health, when consumed in high levels, but today’s air ionizers are federally-restricted in the amount of ozone that can be produced as a by-product of these machines.

At the end of the day, you have to decide for yourself and your family if the benefit of ionized air outweighs the potential risk of increased ozone levels.

Do your research, understand the technology, and move forward into a home with cleaner air.

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About Derek Hales

Derek HalesDerek Hales is the Founder and Editor-in-Chief of He has been featured in Fast Company, Reader's Digest, Business Insider,, She Knows, and other major publications. Derek has a Bachelor's Degree in Business Administration from Kansas State University. Hales has been testing and reviewing products for the home since 2014.

Need Help? Ask Your Question Below

  1. hi there, have you come across of a negative ion generator or machine that of great help to paralyzed person or reversed it thanks

  2. Hi! There are a lot of personal purifiers (necklace types) that has come out in the market because of COVID-19. They are mostly ionisers , that emits from 2million to 120million ions per cm3/second and is suppose to create a safe environment within 3 feet of the user. Supposedly safe for the users . There is also this portable LUFT cube that uses nanotechnology. No filter, no ozone, no ions.

    • Yeah, I’ve seen many of them. Thus far I am extremely doubtful of the claims they make and their overall effectiveness.

  3. I live downstairs from smokers living above me. There are evenings I have trouble sleeping the smell of the smoke is so bad. I used to own a sharper image ionizer and it left the room smelling so fresh and clean all the time I loved that about it. But then it broke and shortly after I heard about the emitting of ozone and it not being healthy so I never replaced it. Now years later I have purchased numerous air purifiers including a Molakule, Bluair, and a Conway and so far not one of them has helped with the strong smoke odor. Do you have any suggestions? I really do miss how the ionizer made my room smell so fresh and clean is there anything else out there that is safe that can do that and get rid of the bad cigarette odor?

    • Since you’ve already tried several air purifiers with limited success I think it’s fair to say you need something more robust. You may consider a system like this –

      This is an in-dust ionization system. It creates high energy particles that are great at dealing with odors and other particulates. The creation of those particles mean it also creates ozone. However, it uses a ozone suppression system, so that the ozone does not get into your air.

      Full disclosure, Clean Air Exp is owned by a personal friend of mine. However, I, nor does Modern Castle have any financial relationship with them. As far as ionization systems go, this is the only one I’ve seen that has the right mix of hardware to create effective ions, while still being safe with respect to ozone.

  4. Hello,
    I have one Honeywell HHT-011 air cleaner with Ionizer for each of my 3 bedrooms. These Ionizers are turned on for 8 hours every day, and I have one Therapure TPP300D with UV + Ionizer that is turned on for 8 hours in my living room. Do you think it is OK for the people in my house?
    Thanks for your time.

    • I’m unfamiliar with those models, so I really cannot say for sure.

      I would suggest you reach out to the manufacturer to better understand if / how much ozone they are putting out into the room. As long as it’s none / less than 0.1 ppm then you should be fine.

  5. Hi. As I read… I have 5 Sharper Image Air-purifiers since 2005 that have ionizer… and just learned today Sept. 19th of all the health concerns. Now I understand why they closed all the stores and went bankrupt. They were irresponsible with their units and with the consumers if this was their primary issue in the law suit.
    Moving on, I don’t know if I have a chance in reporting the machines I still own by Sharper Image. Today I am looking for the best option with no ionizer for a space of 900 sq ft and I found Medify MA-40W V2.0 Medical Grade Filtration H13 True HEPA for 840 Sq. Ft. Air Purifier, 99.9%
    And here someone mentioned the Intellipure Ultra AirPurifier… Which if any you suggest. Thanks

  6. I just purchased a Blaux Portable AC F832. It is very small and has a rechargeable lithium battery. It also has a negative ionizer option. Should I be concerned about the amount of ozone it produces or just operate it without the ionizer? Thank you so much for your help.

    • I would just operate without the ionizer enabled.

      It probably is safe even with it on, but no reason to take a chance, in my view.

  7. I recently had a Reme Halo installed in my A/C system. Immediately it gave off a very “chemically’ smell. I have COPD and emphysemia and have been told that any amount of ozone is damaging to lungs. Should I have it removed?

    • I wouldn’t remove it just yet. Turn it off for now if it’s creating a chemical smell.

      I would suggest you hire an air quality specialist in your area to test the air in your home both with and without it running. You need to better understand the impact it’s having on your air and if that’s safe, given your health conditions.

      Ozone typically isn’t described as a “chemical” smell, so I am doubtful that’s what it is, but it could be (or perhaps something else).

  8. We have a Lightning Air Purifier, LA 1500w, that we purchased about 15 years ago. It states Cascading Tower Technology. We only use it on an occasional basis, but started using it again with the wildfire smoke that we are experiencing.
    Should we have any concerns in using this purifier

    • Unfortunately, I am unfamiliar with that model / brand.

      If it’s producing high volume ozone, then no, I wouldn’t risk turning it on. But if you don’t think it’s using ozone to purify the air then it should be safe.

  9. Hi there!

    I was just informed that someone has purchased a Atmosair Matterhorn 1000 Bipolar Ionization unit for our home as a gift. I’m trying to decide if it’s something I should install or send back.

    I’m confused because on the website it says “A safe, natural and environmentally friendly process. Our patented bipolar ionization technology uses no chemicals, heavy metals or mercury, and produces no harmful by-products such as ozone or ultra-violet light.” But all of my research says that ionizers do produce ozone.

    Would you have any insight? Thank you so much!

    • It is possible that it creates no ozone and/or that that ozone is suppressed.

      I recently had a lunch with a friend who has been working in the air purification industry for 30 years. He mentioned to me that there are some new types of ionizers that do not create ozone (a fact that I was previously unaware of).

      It’s possible that their brand of ionization does not create ozone or that it’s so small it’s negligible. I need to do more research on this specific type of technology to say for sure.

      I’m sorry I don’t have a more clear cut answer.

    • Amanda,
      My research also states that any ionizer creates ozone. The EPA made UL 2998 to identify devices that are acceptable levels of ozone. I believe it is 5 parts per billion. I have also read research on the efficiency and toxicological implications of devices that produce ions and they state that in order to remove the amount of VOC’s and viruses in a real life application the PPB would have to be significantly more than 5 ppb. And this would inevitably lead to ozone being released.

  10. I have an air intellipure.. what’s your opinion on this air purifier .. I am also considering air tamer or anion .. or the portable plasma air purifier using plasma technology .. it very confusing what to choose .. appreciate your opinion. Thank you.

    • We haven’t tested the Intellipure yet, so we cannot say for sure. However, based on the specs and other reviews I’ve seen it would seem to be an excellent air purifier.

      Unfortunately, I’m unfamiliar with Air Tamer and Anion.

  11. I recently used a stand alone Hepa and charcoal filter air purifier. It left a nasty smell in the home and increased the humidity in my home. Any thoughts on this?

    Thank you!

    • Was it new? What was the brand?

      I can think of no reason why it would increase the humidity in your home. That to me seems like there must be another factor at play.

  12. Hi Derek, thanks for the info. I did not see the Dyson HP01 or what is called the Dyson Pure Cool LInk Air Purifier above. Locally that is what is available-would you recommend either?

    • Between those, I would go with the Pure Cool Link (which is most likely the Dyson TP01). HP01 offers purifying and a heat function. So unless you really need / want the heat function, no need to pay extra for it.

      We have an extension Dyson Pure Cool comparison here – – if you’re interested

  13. Hi Derek,
    The RabbitAir MinusA2 air purifier advertises that its Germ Defense Filter “traps and reduces airborne bacteria, mold spores, and viruses”.
    You probably get this question a lot-would that include trapping coronavirus? I thought that the virus was too small to be caught by a filter. Elsewhere I have read that UV emitting machines if they are at the right frequency could kill the virus. But I’ve never seen a claim for a filter that way. What do you think? As always, thanks for your information.

    • Hi Bevan,

      Unfortunately, there isn’t a perfect yes or no answer here. And this isn’t just about Rabbit Air, but about all air purifiers.

      An air purifier can help to keep the air in your home or office cleaner, which can help to reduce the chance of coronavirus spreading. But, there are no absolutes. The EPA does a good job of explaining it here –

      As I understand, COVID 19 and other virus / bacteria are able to become airborne by attaching themselves to particulates that float in the air. This can include water droplets (when you sneeze or cough), dust, hair, fibers, mold, pollen, and a slew of other particulates. Air purifiers are able to reduce bacteria and viruses in your home by pulling these floating particulates out of the air and trapping them within their filters. That’s how the Rabbit Air’s germ layer works, and basically how any filter works.

      While the virus themselves may be too small, the virus is hitching a ride into the air on larger particles. It’s those larger particles that are trapped, collectively trapping the virus also.

      As far as UV light, I’m not as knowledgeable about UV light. From what I’ve read and watched it seems to be an impressive technology. However, it be effective they need to be on for an extended period of time and extremely bright. Most of the UV light consumer grade products aren’t bright enough or on long enough to be effective.

  14. Does anyone have any thoughts or advice on CWR’s rechargeable personal Air Purifier. I am a school teacher going back into the classroom would this help at all with Covid 19

    • We haven’t tested it yet, but a quick look at the product’s form factor really makes me question the effectiveness.

      I understand it’s only for personal use, but I am doubtful that it’s capable of pumping out enough air flow to have any significant impact.

    • We haven’t tested it, but based on a quick look at the specs, it is an ionizer, which means it most likely creates ozone. However, given the size, the level of ozone is probably within what the federal government considers safe.

      That said, given the size I am doubtful that it’s capable of having a significant impact on air quality around you. And for $150…yikes. I certainly would not buy it.

  15. Hi, I have an air oasis iadaptair M

    It has uv light hepa and bipolar ioniser. First time using I felt terrible. I assume it’s the ozone from the ioniser. Is it even worth keeper at all or will a standard hepa do just as good? All this information about ozone I’m worried to ever try it with the ioniser setting.

    • Hi Lee,

      If it’s making you feel sick you should get rid of it.

      HEPA filters do just as well as high power ionizers, but without the dangers. Most hospitals still use HEPA filtration, quite simply because it works.

      See our list of air purifier reviews here – – The vast majority are HEPA-based.

    • I would not.

      It appears to be an ionizer. I’m amazed after all of the bad press (and rightly deserved) from the 1990s / 2000s that ionizers like this still exist.

      If this machine creates enough high energy ions to be effective then it’s dangerous due to the level of ozone created. If it doesn’t create enough high energy particles then it won’t be effective. It’s a catch 22 and one that involves your health / safety. To me, it’s not worth it.

  16. Any review you can give me about the Brookstone Pure-Ion advanced ionic air purifier with ozone control? Thank you!

    • I read a few product reviews and I cannot find any models that say “with ozone control”, so perhaps I’m looking at the wrong models.

      In any case, the product descriptions I’ve read leave me worried. It seems like a pretty typical ionizer. If it is (and that’s an if, as I am not 100% sure), then it is dangerous.

      All the places I looked are out of stock / not for sale…that feels to me like it may have been pulled from the market at some point. Given the lack of clear information in the product description I would not ever buy a product like this for my home.

  17. My 2009 Toyota Camry says that it has negative ion air-conditioning. I have never heard of any recalls or problems with it but I do have concerns. Should this be something I need to worry about?

  18. Hi, is the I-wave-R product ok to use? it is installed in the air conditioning system behind the filter. Was offered and installed by my air conditioning company.

    • I’m not familiar with that model, but a quick read through their page makes me a little uneasy. Doesn’t mention anything about ozone suppression or a lack of ozone.

      I would suggest you inquire on whether or not it’s generating and/or suppressing ozone.

    • Hi,

      I inquired with the IWave company. They claim only a very small amount of ozone is released when it first turns on. If on continuously there is basically no ozone… any thoughts?

    • If it’s creating a small amount of ozone then it’s probably safe. You just want to avoid air purifiers that create large volumes of ozone, which can be dangerous.

  19. We need to install air filtration and purification in our house using either room units or something installed into our HVAC system. Considering Molekule stand alone units for each room vs. installing a bi-polar ionization system in our HVAC along with HEPA filtration. The bi-polar unit being considered is similar to the I-Wave R. Since our main concern is killing and eliminating mold particles, would the Molekule be the better choice? A bi-polar system, it seems, would cause any airborne mold particles to fall to the ground but wouldn’t eliminate them unless vacuumed up later whereas the Molekule seems like it would not only kill the particle but also eliminate it completely. Thoughts?

    • That’s generally the way ionizers works (at least to the degree of my understanding). If that’s your primary concern then yes, I would think a standalone air purifier, be it Molekule or something else, would be a better choice for you.

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