Re: Sharp vs BlueAir vs RabbitAir BioGS for smoke seepage & Nanosilver safety

A Reader writes:

Hello Ed -

Your website has been extremely helpful to me; thank you so much!

I'd like to pass on some information which might be of use, and also ask you a few questions.

I live in a two room New York City apartment (one room 12 x 14, the other about 13 x 20, both with 10' ceilings).

There has been a recurrent problem with second-hand smoke seeping into the larger room from an adjoining apartment during the day, and during the night I find it helpful to run an air purifier in our bedroom (the small room) to reduce dust and dust mite allergens to reduce my tendency to snore (which can keep my wife awake).

I would just get one air purifier, and move it back and forth between the rooms as needed.

Since my wife is a light sleeper, it needs to be QUIET, and since we have made a real effort to reduce our energy consumption over the past few years, any new appliance which will be running near-continuously needs to be very low power.

I'd pretty much settled on the Sharp FP-P60CX, but Sharp tech support just confirmed to me that it has in fact been officially discontinued.

The KC-C150U humidifier/purifier which replaces it has several problems.

Since I need a humidifier anyway, I actually wouldn't mind purchasing such a combination unit.

However, the KC-C150U lacks the ability to switch between Plasmacluster and negative ion generation (the only option is to just switch Plasmacluster on or off), and the odor sensor of the FP-P60CX has been replaced by a dust sensor (both of these facts confirmed by Sharp Tech support).

Additionally, from reading the manual I get the impression that the sensor technology is less sophisticated than that in the FP-P60CX.

I've given some thought to getting the FP-P40CX, which is still being made and has the same features as the FP-P60CX; however, am I correct that this unit is probably a bit small for my needs?

If the Sharp is eliminated, that really leaves one of the Blueair 400 Smokestop series or one of the Rabbit air purifiers.

I don't mind paying the higher upfront costs of the Blueair, but the $120 filter replacement cost (theoretically every 6 months) is a killer.

Several questions: do you think it would be possible to tape some sort of prefilter material to the intake vents of the Blueair to extend HEPA life, or would this interfere with proper operation of the unit?

Cost issues aside, do you think that the Blueair unit is likely to deal with second-hand tobacco smoke more effectively than the Rabbit Minus A2? (I'd run the Rabbit with the 'toxin' 4th stage filter, which Rabbit tech support said would be effective against smoke).

I would probably go for the Rabbit Minus A2 SPA700, since it is one hundred dollars cheaper than the SPA 780, and according to Rabbit Tech support its performance would be identical except that it moves roughly 20 percent less air at each fan speed setting (which means in effect that the 700 can achieve similar performance to the 780 except at the 780's highest speed, which I would be unlikely to use because of noise).

One other concern about the Rabbit: it boasts a 'nano-silver' prefilter.

As you may be aware, there is some concern about the so- far untested consequences of the wide-spread adaption of nano- technology, and nano-silver may potentially be particularly toxic.

More information can be found here: Friends of the Earth - nanosilver , and specifically in the quite detailed pdf of the full report which the web page links to.

Full FOE Nanosilver Report (.pdf document, requires Adobe Acrobat)

Even if the use of nano-silver in this particular application does not pose a threat to the home user, I'd be concerned about the environmental consequences when the unit is eventually disposed of, and also about the health consequences for the workers who built it.

I'm also a bit concerned about Rabbit's BioGS Hepa filter, which Rabbit claims is made of a germicidal material that "has the capacity to disintegrate allergens on the filter."

Any idea exactly what sort of technology or chemical they are making use of to accomplish this?

I'm not thrilled about the long-term effects of indiscriminate release of bacterial killing agents into the environment (essentially, this just encourages the evolution of increasingly resistant super-bugs).

Thank you for any thoughts you might have!

Best wishes,

A Reader

Ed's Reply

Hey Reader;

Realize that second hand smoke seepage is a very difficult air cleaner issue. The subtle odor and irritation will be elusive, especially if your mystery smoker lights up erratically.

You have chosen well, all three purifiers are still being supported in the "recession."

Realize that many manufacturers have downsized, cutting models and support.

1. Sharp KCC150U.

I still like the Sharps, despite the faults coming to light.

Dropping the FPP60Cx was done very quietly, allowing inventory to move and filters to dry up.

KCC150U is actively promoted by the company, and the negative ion function is not essential to operation.

The sensor issue is dealt with in another email post, see;

Dust sensors found lacking

Since you desire humidification, I'd still keep Sharp KCC150U on your list.

The active plasmaclusters will deal with subtle secondhand smoke seepage better than passive filtration.

Using distilled water cuts down on cleanup chores. Sharps are very quiet.

FPP40CX, AHAM certified to 253 sq. ft., is a bit light for your bigger room.

But you could get two Sharp FP-P40CXes for the cost of ownership of a Blueair.

2. Blueair 400 series.

The Blueair is a premium market brand, a couple steps higher in price and upkeep costs than the Sharp/Rabbit.

Blueair's design is built to render high CADR tests, and obviously to produce long-term downstream revenue from the filters.

This high-throughput keeps Blueairs from being totally quiet, there is a whistling sound some dislike.

I would love to try putting the obvious experimental prefilter package on a Blueair to check filter life. Blueair filters fill up with coarse particles - visible dust - it is very possible that a good prefilter would extend filter life and reduce cleaning chores.

But forget a warranty claim on the high-dollar Blueair if you don't buy filters on schedule.

I have burned up a couple cheap machines with my prefilter experiments.

While my IQAirs run flawlessly with extra prefilters - they're designed to run IQAir's optional coarse dust catcher - Blueair experiments are not contemplated unless I find one cheap on craigslist.

3. RabbitAir MinusA2 SPA700

MinusA2 is very modern, quiet and energy efficient, with long filter life.

And RabbitAir has some of the best service/support in the industry.

Your post raises environmental questions with no easy answers.

I agree with Friends of the Earth and your concerns on the potential environmental effects of industrial scale production of nano-silver and germicidal chemicals.

But I have seen no evidence, and Friends of the Earth's documents do not suggest, direct human health effects from using silver-coated air purifier filters.

It is indeed possible that nanoparticles could be disbursed from these filters, but exposure should be minor compared with products designed for oral interaction like baby bottles/nipples, water filters, toothpaste, shampoos, food products and food packaging.

Clothing and fabric items, and women’s hygiene products in direct contact with skin would be another obvious area.

BioGS Hepa filter is a product of Japanese corporate giant Mitsubishi Heavy Industries (MHI).

Microorganisms trapped in the filter can be killed to prevent "secondary contamination," where the filter breeds the bug.

But I am highly skeptical of all air purifier marketing claims which assert ability to control virus transmission.

Bio GS is claimed to be "coated with anti-influenza virus agent," without many specifics.

But we can derive clues from previous MHI designs.

A earlier MHI HEPA filter, named "Bio ALLOS," had silver on the front and copper on the back.

I suspect this is very similar to Bio GS, with a progression something like;

BioALLOS > BioHEPA > BioFresh > BioGP > BioGS

MHI has also used catechin, a bioflavonoid made popular by green tea, and known for its antimicrobial, deodorizing, and antioxidant qualities, in some filters.

Enzyme-impregnated filter paper was first developed by Tokyo-based Nikki-Universal Corp. under the name Bio-Free.

Enzyme filters consist of glass or rayon fibers, to which lytic (digestive) enzymes that are uniformly bound throughout filter media.

MHI's BIOHEPA bacteriolytic enzyme filter, jointly developed with Nikki Universal, was featured in Mitsubishi's Asian marketed MHI CT455D-S purifier, a precursor to today's American market Mitsubishi-based purifiers (some RabbitAirs).

Enzymes in these filters dissolve viral envelopes, fungal hyphae, and bacterial cell walls.

Builders assert that these bacteriolytic enzymes are commonly found in human bodies, and are harmless if touched.

Enzyme filters are used in Japanese hospitals and clean rooms, and widely copied elsewhere in Asia, notably by Taiwanese filter makers.

We are surrounded by hundreds of thousands of innovative - experimental - and very dangerous products.

Genetically modified organisms and foods, fossil fuel combustion byproducts like addictive acetaldehyde, radioactive waste and depleted uranium munitions, biological warfare agents distributed in food and medicine, electromagnetic emissions from myriad devices, recombinant growth hormone, irradiated fruits and vegetables, and thousands of everyday chemicals whose effects are unknown, are the tip of an iceberg.

I have warned users about dangers of ozone, other oxidant air cleaning technologies including Sharp Plasmacluster, electromagnetic and radio frequency emissions, and even fire hazards associated with some air purifiers.

I don't think the possible catechins and definite enzymes in the Rabbit's BIO GS filter pose any threat to users.

In my opinion, the RabbitAirs are safer than many of the best selling air cleaners, including Sharper Image Ionic Breeze, Oreck, Ecoquest, and Frederich.

I expect that the net result of environmental groups lobbying on silver will be to restrict the sale of colloidal silver herbal alternative medicine remedies, a minor use which Friends of the Earth singles out, from the long list of gross industrial-scale offenders, with repeated specific demands for regulation.

"We believe that all over-the-counter colloidal silver products should be immediately withdrawn from the market and their sale should be banned..."

Friends of the Earth Report - Nano and Biological Silver

Industrial, medical, food handling, and manufacturing nanotech silver uses likely will go untouched or lightly regulated.

Any industrial product you use, including basic necessities like food, has serious negative environmental repercussions. Food itself is a focus, with serious safety issues.

Many products have negative health consequences for production workers, with varying degrees of severity depending on country of origin.

We are starting to see "green" air purifiers coming to market.

See for example, "style over substance" in my review of the pricey Alen Paralda "green" air purifier;

Alen Paralda - green machine

I personally would not reject the otherwise excellent RabbitAir products, service, and support solely on environmental grounds.

So I'd consider the Sharp KCC150U, dual Sharp FPP40CXes, RabbitAir MinusA2 SPA700, and Blueair 450e, in that order, for your smoke seepage.

Best luck and waiting to hear your results with whatever machine you pick.

Ed