Strange but true. It is very, very difficult to find well-organized and well-documented scientific research on the technologies behind ionic air purifiers, a multi-billion dollar global industry!
Weird Because if the science is solid, I’d expect any ionic air purifier manufacturer to tout the science behind their brand. I would expect them to expose the efficacy and effectiveness of their unique technology. Furthermore, I would expect them to reassure users profusely that their technology is perfectly safe, that it kills microbes but is perfectly harmless to humans. Unfortunately, my expectations are not met.
Real because I have spent countless hours searching for scientific white papers that support the technologies behind existing ionic air purifiers on the market, and yet I have very little to show for it. Whether deliberate or not, marketers of ionic air purifiers simply don’t bother to post scientific articles on their websites. When they do, they make no distinction between the safety, efficacy, and effectiveness of their specific brands. The scientific references are mentioned only briefly and do not provide enough detail for serious prospective buyers of the particular air purifier to study. It is as if the manufacturers do not expect anyone to question and examine their products!
Inaccessible scientific research
Where I have come across relevant scientific research articles on the web, they are not easily accessible as they are normally cost prohibitive, charging per article! I guess if I’m an entrepreneur looking to make a new ionic air purifier, I’d be willing to invest in the hundreds and possibly thousands of technical articles listed on some scientific journal websites. But I’m just looking for a reliable and safe product to buy for my personal use!
It is unfortunate that the scientific world is also commercially driven, so research of great importance is not made available to everyone who is interested or needs to know.
logical criteria
However, while my head is still spinning from the avalanche of confusing and inconclusive web data, my search for the ideal air purifier continues, following these criteria:
(1) Safety: Ionic air purifier technology should not cause any bodily harm to users;
(2) Efficacy: Ionic air purifier technology has been laboratory tested to really work based on some extensive scientific research;
(3) Efficiency: Ionic air purifier technology has been successfully transplanted from the laboratory into a device that will provide the same results in a user environment, ie home, office, factory, school, etc.
Security issues
In this article, I want to focus on the safety of ionic air purifiers, a factor that I believe overrides the other two criteria of efficacy and effectiveness. There is no point in having something that works wonderfully at killing microbes but is so powerful that it harms our health. Two important questions need to be answered:
(1) Do the purported beneficial active agents in ionic air purification technologies cause harm to human tissue? Are Negative Ions, Bipolar Ions, Hydroxyl Radicals, Sharp’s Proprietary Plasmacluster Ions or whatever name you give them safe?
(2) Do the unwanted by-products of ionic air purification technologies cause any harm to human tissue? By-products include ozone and nitric oxides which are highly reactive and known to be harmful in high concentrations.
Beneficial Active Agents: Do They Harm Human Tissue?
There is no scientific data available on the web on whether negative ions, bipolar ions, hydroxyl radicals, plasmacluster ions, etc. they are safe in the sense that they do not harm human tissue. There is plenty of data to show that these active ingredients effectively kill microbes, which I will cover in a later article. Here I am concerned that the full potency of the active agents is equally destructive on fragile human tissue. Why is there a dearth of scientific data when consumers spend millions of dollars on ionic air purifiers each year?
After extensive but unsuccessful web searches, I did the next logical thing: ask the manufacturers of ionic air purifiers! After a few queries, the answer gradually became clear: the scientific data exists, but the manufacturers do not want to make it public so as not to provoke the wrath of animal welfare groups. Is this a real fear or are they hiding some unpleasant truth about their product?
Googling “animal testing” immediately sparked the huge controversy surrounding the use of animals to test the safety of products intended for humans. An example would be Huntingdon Life Sciences, a UK research company that conducts safety testing of commercial products, pharmaceuticals and household appliances. To this day, there is a lot of conflict between testing companies and animal welfare groups. No wonder the cloak of secrecy from ionic air purifier manufacturers is likely to conduct safety tests using similar testing companies.
Documented animal testing
A casual web search result helped me better understand the animal testing controversy. The safety tests mentioned on the website relate to a liquid product, not directly related to any ionic air purification technology. The liquid is applied on furniture and other domestic accessories. In the explanation of one of the benefits, it is stated that when ultraviolet light from sunlight strikes the liquid, hydroxyl radicals and superoxide ions are released into the air and thus destroy any microbes such as bacteria, viruses and mold that may be present.
To prove that the liquid is harmless to humans, four categories of safety tests were conducted on mice, guinea pigs and rabbits (please note that the following paragraph may be offensive to you and you may wish to skip to the next paragraph).
They are:
(1) Acute oral toxicity test: the liquid was orally fed to mice;
(2) Primary skin irritation test: the liquid was applied to deliberately scraped skin of rabbits;
(3) Skin sensitivity test: the liquid was injected under the skin of guinea pigs;
(4) Mutagenicity test: the liquid was applied to salmonella bacteria to determine whether they caused mutation in the bacteria nuclei to determine whether the liquid has the ability to cause cancer.
unharmed animals
Pretty gloomy and repulsive stuff! I’m sorry even though reports indicate that the tests were conducted in accordance with the Organization for Economic Co-operation and Development (OECD) Guidelines for Chemical Testing. I can begin to empathize with the animal welfare field about such safety tests. Fortunately, for this liquid product, all animals (including salmonella bacteria) were unharmed by its application.
This brief overview of animal testing explains why ionic air purifier manufacturers refrain from advertising or even mentioning such tests when they are conducted.
Security footnotes
Despite this concern from manufacturers, my web searches have revealed footnotes for certain brands indicating that active agents have been tested for safety. When searching for my ionic air purifier, I would be looking for those footnotes. I would hope that no animals have been harmed or that the purifier has no good reason for being on the market for humans. I would also ensure that safety testing is done by accredited institutions that are GLP (Good Laboratory Practice) accredited, a set of principles issued by the OECD to recognize organizations that meet strict scientific testing standards.
human trials
Ultimately, does this mean that there really is no safety evidence for the effects of active agents in humans using ionic air purifiers? Hardly, if you think about it. All users become testers, having unknowingly volunteered by the act of buying one and using it!
Unfortunately, all you’ll hear on manufacturers’ websites will be glowing testimonials to the purifier’s benefits. Such testimonials, while helpful, come under the cherry-picking cloud, meaning only positive ones are featured. To be considered strong scientific proof that the active agents do not cause harm to human tissue, the operation of the ionic air purifier by users would have had to be subject to very strict testing criteria and parameters of a GLP laboratory.
It would seem that this is a problem that will never be adequately solved. The only consolation for me is that many other products on the consumer market are sold in the same way, solely in the good faith of the manufacturers and are considered safe until proven otherwise.
Security – Second Aspect
In a future article, I will discuss the second aspect of security. Aside from the active agents, human tissue can also be damaged by possible by-products, deliberate or not, of ionic air purifiers.