New Research: Ionizers are "Negative" for Health

[IndoorAirNerd]

A recent study found that the negative air ions generated by air-cleaning ionizers have a harmful effect on humans. Specifically the researchers found an increase in a biomarker of systemic oxidative stress.

Although ionizers have the benefit of removing airborne particles, the researchers conclude that the benefits do not outweigh the negative effects. Here is a link to the abstract, which is in the Indoor Air Journal: https://onlinelibrary.wiley.com/doi/10.1111/ina.12728

Bottom line: for removing particles, HEPA will be a better option.

p.s. I don't sell any air purifiers, I'm just an IAQ consultant!

[Jim Davis]

If China says it, it must be true!

[kangaroogod]

A recent study found that the negative air ions generated by air-cleaning ionizers have a harmful effect on humans. Specifically the researchers found an increase in a biomarker of systemic oxidative stress.

Although ionizers have the benefit of removing airborne particles, the researchers conclude that the benefits do not outweigh the negative effects. Here is a link to the abstract, which is in the Indoor Air Journal: https://onlinelibrary.wiley.com/doi/10.1111/ina.12728

Bottom line: for removing particles, HEPA will be a better option.

p.s. I don't sell any air purifiers, I'm just an IAQ consultant!

What about virus, bacteria and voc remediation?

Sent from my SM-N960U using Tapatalk

[fourelements]

good to know

[teddy bear]

Prime is the idea of a filtered fresh air change in 3-5 hours to purge all of the indoor pollutants and renew oxygen when occupied. By maintaining <50%RH mold/mildew/dust mites/other biologicals are avoided.
A well setup a/c combined with small whole house dehumidifier makes most homes healthy and comfortable.
Regards Teddy Bear

[fourelements]

what abot UV bulbs?Lot hvac companies offer against viruses too

[IndoorAirNerd]

What about virus, bacteria and voc remediation?

The research didn't specifically look at the effects ionizers may have at reducing VOCs, viruses, and bacteria... it focused on oxidative stress that negative ions can cause when the ionizer is operating.

[IndoorAirNerd]

what abot UV bulbs?Lot hvac companies offer against viruses too

UV bulbs, if designed to produce ozone, would create oxidative stress too; albeit in a different way from ionizers. Bottom line you want to avoid oxidative stress. You see TV commercials for products like pomegranate juice that are "rich in anti-oxidants" (which counter oxidative stress). So things that produce ozone and other reactive oxygen species (ROS) should generally be avoided.

[Tekjunkie]

Around here I see A LOT of people pushing for I-waves. It uses bi polar ionization but my concern is that does it cancel each other out and kill off the pollutants before becoming damaging to ones health?

[randyf]

Very interesting and nuanced findings.
From the Abstract:

Increases in PM2.5 and negative ion (NI) exposure were independently associated with increased urinary concentration of malondialdehyde, a biomarker of systemic oxidative stress, resulting in a null net effect of NIAP on malondialdehyde.

So having the machine on or off resulted in the same level of oxidative stress. PM 2.5 was associated with just as much oxidative stress as the negative ions.

[randyf]

The I-wave might reduce particulate pollution, but,contrary to the claims of GPS, will do nothing for VOCs.

[Tekjunkie]

The I-wave might reduce particulate pollution, but,contrary to the claims of GPS, will do nothing for VOCs.

Has this been proven? Either way it still sounds like air purifiers are just band aids to a problem.

[randyf]

Has this been proven? Either way it still sounds like air purifiers are just band aids to a problem.

Very fair question. I apologize in advance for the long winded nerdy explanation that follows. My wish is for more folks like yourself to become conversant with this stuff to call out manufactures on their unfounded claims.

There are three basic method to mitigate VOCs.

1. Ventilate and dilute. This is fast and effective. Teddy is a champion of this approach (along with humidity control). This works!

2. Trap and sequester ala activated carbon (and other substances). This also works. I've got a couple of 30 and 15lbs carbon canisters and I"ve measure results.
But there are drawbacks.
Carbon loses effectiveness much faster than most realize. And carbon is picky - it likes some VOCS more than others. Also when temps rise > 78 it can desaturate and release previously trapped VOCs. Same thing happens when humidity rises.

3. Destroy VOCs.
What destroy means in context is to break apart the carbon and hydrogen bonds of VOCs leaving just H2O and Water. This *breaking apart* process is called oxidation.

How is ths done? By generating *oxidants*.

What are oxidants - Ozone, Hydroxlys, Hydrogen Peroxide, Super Oxygen and others

Do these work? Sometimes, in certain contexts, but there are downsides.

What's the best oxidant? Hydroxyls are by far the most powerful. Ozone, although very cheap to produce in quantity, is a bit of a double edge sword.

What are the downsides?
Sometimes smaller, more dangerous VOCs are produced. Some claim that Hydroxyls can damage human tissue, but I don't think so.
Ozone in quantities needed to destroy VOCS is definitely damaging to the body but this treatment will only be used in unoccupied areas. Ozone in high quantities can also produce Ultra fine particulate matter, which is definitely a negative.

How are "Hydroxyls produced?
1. Photo-Catalytic- Oxidation. This process involves radiating a special metal catalyst with UV light. The hydroxlys produced have a life span of < 1 second so they don't travel very far.
Has this approach been proven to work?
Yes but there are caveats.
a. Most studies have shown effectiveness in High concentrations of specific VOCs. There is little data showing effectiveness with concentrations found in homes/offices.
b. This is some concern about the intermediate byproducts being more problematic that the original offending VOC. Other studies give these devices a clean bill of health

2. The other method to produce Hydroxyls are bipolar ion generators. But, and this is a big but, the method used differs significantly from the needle point method that the IWave and GPS uses. The needle point method does not product Hydroxlys.
The Iwave does produce bipolar ions and this is useful for particulate reduction but won't do squat for VOCs.

GPS conflates Ionizaton with Oxidation. These are two fundamentally different processes. On their web site they list the ionization potential of various VOCS. They then take the incorrect leap that since their products produce Ionization potentials greater than most VOCs their product destroy these VOCs. Not So. The ionization potential of VOCs is the energy needed to strip electrons off the outer shell of a compound Not the energy needed to break apart carbon/hydrogen bonds.

Their claims for VOC reduction are misunderstanding of basic science.
If I'm wrong (and I could be) it would be easy enough to GPS to demonstrate. All they need to do is rent the appropriate gear(it's not that expensive) and take measurements. I would be thrilled if it worked.

[Tekjunkie]

I'd rather have long winded and nerdy explanations. I would consider myself a citizen scientist and nerd.

Yea, I'm very familiar with activated carbon. We use it here at work in one of the laser extraction systems and it doesn't last long. But it also is impregnated to absorb most of the VOCs that the rubber gives on during the laser engraving process... or so they say. Which brings me up to two different solutions, ERV or I-wave. But this morning I noticed that one of the anemic exhaust fans its able to overcome negative building pressure due to the other Laser exhausts fans in the back (or I assume this, more testing is needed).

I think I will install an ERV at home also, My CO2 goes up to 1600ppm at times and my house is only getting tighter. Im at less then 4ACH50.

[lofi]

that is very sad, cause lots of people trusted them for a long time

[teddy bear]

I'd rather have long winded and nerdy explanations. I would consider myself a citizen scientist and nerd.

Yea, I'm very familiar with activated carbon. We use it here at work in one of the laser extraction systems and it doesn't last long. But it also is impregnated to absorb most of the VOCs that the rubber gives on during the laser engraving process... or so they say. Which brings me up to two different solutions, ERV or I-wave. But this morning I noticed that one of the anemic exhaust fans its able to overcome negative building pressure due to the other Laser exhausts fans in the back (or I assume this, more testing is needed).

I think I will install an ERV at home also, My CO2 goes up to 1600ppm at times and my house is only getting tighter. Im at less then 4ACH50.

How many are in the space while 1,600 PPM CO2? If the air in the space is well mixed, you are getting +-15 cfm of fresh air per average size inactive adult. The critical issue is getting enough fresh air change to purge the indoor pollutants. 20% O2 is about 450 PPM CO2. This is about as good as fresh air gets. Your 4ACH50 is typically an average winter day. As wind and stack effect declines the ACH declines. A foam home in during mild calm conditions will be <12ACH. We can survive 5,000 PPM for short periods of time. 15% O2 is thought to be too low for extended time.

So, most of us depend on O2 for survival. Try a plastic bag for 3 mins!
Interesting stuff.

20% O2, 40-60%RH. Filter to you needs.
Pick the temperature you like. You want an ionizer-be my guest, I do not know.

Very few of us have these levels of control.

Regards Teddy Bear