Fine AirBorne Particles and Health

Recent toxicological studies have confirmed that airborne particles in the ultra-fine size range can disrupt basic cellular functions, contributing to many diseases. Sub-micron particles float in the air longer, drift farther and are inhaled deeper.

The particles we can actually see in a shaft of sunlight represent about 10% of those floating in indoor air.

We are in the habit of thinking that what we can see is "dust", and that if we don't see anything, air is "clean."

Unfortunately, this is not true.

In many homes without an obvious source, such as resident tobacco smokers, air is dirtiest right after the vacuum cleaner runs.

Particulate densities as high as 8,000,000 particles/cubic foot have been measured in rooms being vacuum "cleaned." This is especially the case in homes with deep carpets.

Particles seen accumulating on furniture or visible in a shaft of light are 50 microns or larger. The great majority of particles are 3 microns or smaller. Submicron particulate (less than 1.0 micron) sticks to surfaces, including in our lungs, by molecular adhesion.

100,000 such pipsqueaks could hide on the head of a pin. With relative air borne particle size, a visual is worth a thousand words.

The best way to visualize size is this zooming graphic from cellsalive.com: the smallest airborne particles are beyond microscopically small.

This graphic is about microorganisms, but the relative sizes of particles are very similar.

It opens in a new window, wait till it loads, then click on the words "start the animation." (sometimes it takes 2 clicks, worth the wait) Click on the little blue arrows to zoom;

Very Cool Visual Size Graphic

PENETRATION

We are accustomed to thinking about "allergens" like mold spores, pollen, and dander, but these are relatively large, causing only superficial inflammatory responses.

Dust mite allergen measures from .1 to .3 micron, but resides largely in bedding and stuffed toys, rather than becoming airborne.

Superfine .1 micron particles easily penetrate the body's defense mechanisms.

Studies show these cause more inflammation than larger respirable particles made from the same material.

The smallest airborne particles go through the lungs, circulate in the bloodstream, and penetrate cell walls.

These fine particles serve as nuclei for attached chemical molecules.

They have a very large surface area to mass ratio, which allows them to provoke significant irritation in living tissues.

HEALTH EFFECTS of TINY PARTICULATE

Particulate in our bodies triggers an inflammatory cascade, such as occurs in asthma.

Ultrafines oxidative stress and inflammation are one health robbing mechanism.

However, research has shown particulate accumulation at the sub cellular level.

Mitochondria are the energy factories that keep us alive, very fine particulate can distort shapes of these organelles, reducing cellular vitality.

Damaged mitochondria are implicated in Parkinson's and Alzheimer's, and other neurodegenerative disease.

The chronic cardiovascular diseases are now (belatedly, after 30 years of "dietary cholesterol" propaganda) being linked to inflammatory processes.

HOUSEHOLD SOURCES

We now possess technology to measure invisible particles.

One thing is very clear: indoor burning is the biggest airborne residential health hazard

All combustion results in ultrafine particulates and there is no safe level.

Tobacco smoke measures .01 microns and up, oil Smoke starts at .03 micron, below the abilities of the majority of air purifiers mentioned here.

Electrostatics loose efficiency after a coating of oxidized oils fouls their collector plates.

Many HEPA rated filters fail to live up to the rating in practice (99.97%@.3 micron).

While the theoretical efficiency of these filters is challenged most by a .3 micron particle, smaller ones routinelyslip through cheaper HEPAS.

These have creases and cracks, glue strips, and joints to frames, which make smaller-than-pinhole leaks.

Cooking, a practice we take as given, has many health robbing attributes.

We may want our air purifier to remove the odor, but we rarely think of the often invisible particulate that accompanies it.

Skillet or deep-fat frying inevitably creates smoke in all particle sizes.

I had a wood stove for many years.

I loved the quick warm up on cold mornings, and had ample free fuel.

My stove back-drafted, releasing a puff of nasty smoke, whenever the door was opened to load more fuel.

Ash removal always resulted in a mess. I was very fond of that 19th century throwback.

A neighbor of mine had built his home around a wood burning stove. When he died of lung cancer, I took out my stove.

Humans have lived for thousands of years immersed in smoke, dying young of respiratory infections.

We routinely ignore it at campfires, birthday parties, tailgatesand grill outs.

A couple years ago, camped at a ridge line shelter on the Appalachian trail, our group was engulfed by thick smoke from a downhill forest fire.

We were surrounded, several hikers panicked.

Thick forest fire smoke is on a par with CS gas (strong tear gas), only you can't outrun it.

One guy climbed to the top of the mountain and called the forest service. They responded that it was a "controlled burn" and we were safe.

Combustion, even from "clean burning" gas appliances, produces carbon particles carrying high positive electrostatic charges. These flock together and stick to everything.

The biggest mistake I find repeated with consumers buying air purifiers is the expectation that an air purifier can compensate for pollutant sources left in place.

These may include indoor burning.

These invisible airborne particles remain after the majority of mass market air purifiers sold today have done their best.

Ozone makes air smell good, cheap filters make it look clean: it seldom is.

So what is the moral of this story?

Remove pollutant sources from your living space and over install more than one air purifier.

I start with an IQAir, best at .1 micron efficiency, and build from that base.

Health Risks of Exercise in Air Pollution

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