Small, wearable necklace air purifiers have become popular to protect against viruses and other pollutants. They’re small, lightweight, portable and fairly cheap. Here’s an Amazon listing for one which claims to eliminate germs, dust, viruses and more from the air.
In the Philippines, President Duterte has been seen wearing a portable purifier around his neck during meetings in the Philippines, and while travelling to India.
But the big question is: do these portable purifiers actually work?
In this article, we take a deep dive into what wearable air purifiers are, how they work, and whether they can really protect against viruses, PM2.5 and other pollutants.
Wearable Air Purifiers: What Are They?
Wearable air purifiers work differently from typical home air purifiers. More often than not, they use ionizers and ionization technology as a means to filter out pollutants from the air.
Most non-portable home air purifiers, on the other hand, use HEPA filter technology to filter out pollution.
Wearable ionizer purifiers work by emitting thousands of ions into the air every minute.
These emitted ions attach to pollutants in the air, giving them a static charge. Just like a balloon sticks to a wall when it’s been statically charged, the charged particles are then more likely to stick to whatever’s near them.
Personal Air Purifiers: Can They Protect Against Viruses and Other Pollutants?
A study by scientists in China and California tested the effectiveness of 4 wearable ionizer air purifiers. They put each wearable air purifier in a 0.46m3 chamber about the size of a dog kennel. They then measured how well each portable air purifier removed tiny particles from the air. The results? 3 of the 4 wearable ionizers tested removed less than 10% of particles 20 cm away from it.
10% protection isn’t great, and far lower than the 95% virus-protection you get from wearing a mask. What’s more, these tests of personal air purifiers were done in small enclosed 0.46m3 chamber, with no moving air. It’s likely these wearable air purifiers would perform even worse when worn around the neck in the real world.
The data above shows wearable ionizer purifiers don’t work well at purifying the air. But what’s the harm? Surely wearing a portable air purifier and getting 10% protection is better than nothing?
Ionizer Wearable Can Harm Your Body
In addition to studies showing wearable purifiers are not great at cleaning the air, there are also other concerns.
1. Wearable Purifiers Create Ozone
Various studies have shown wearable purifiers can create ozone, due to the use of an ionizer instead of a HEPA filter. Ozone is harmful to humans and can damage lungs. The exact amount of ozone created by each personal purifier can vary widely, but the average consumer has no way of knowing for sure the levels of ozone created by their device.
The exact amount of ozone created by each ionizer can vary widely, but some have been shown to produce harmful levels.
The ozone concentration [produced by wearable purifiers] at human breathing zone may reach up to a harmful level if wearable ionization air cleaners are utilized under calm air conditions.Shi et al. (2016). Performance of wearable ionization air cleaners: Ozone emission and particle removal
Some marketers have tried to sell the consumer that the ozone produced by ionizers is different than other ozone, and therefore not harmful. This is false, as explained by the EPA:
There is no difference, despite some marketers’ claims, between ozone in smog outdoors and ozone produced by these devices.United States Environmental Protection Agency
2. Wearable Purifiers Interfere With Personal Care Products
The ozone produced by wearable purifiers may even have other serious health risks.
Studies show ozone can react with terpenes in personal care products including lotions, perfumes, makeup and other scented products. These ozone reactions can result in the formation of dangerous VOCs such as formaldehyde, as well as PM2.5 particulate matter. All of this would be taking place in the head region. Yikes!
3. Portable Purifiers Can Make Pollution Stick to your Face & Clothes
Ionizers work by making pollution stick to nearby surfaces, removing them from the air. But if the nearest surface is your body, there’s a problem.
When wearing an ionizer air purifier, your face, body and clothes act as the magnet for the pollution to stick to. This could result in dirty clothes and skin, or even breathing in more pollutants than you otherwise would.