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Medical Science and Mold

A beginner's guide to some of the medical implications behind mold exposure

By Jason Earle Google+

Source: Habitat Quarterly

So what’s wrong with a little mold in the house? Maybe a lot. Top rated medical research organizations have linked indoor mold exposure to a litany of woes, including asthma, chronic sinusitis, a variety of other respiratory ailments and, yes, even depression.

Most Americans spend the vast majority of their time indoors, either at home, at work or in school. And that’s where the worst air pollution crisis in the country exists. The US Environmental Protection Agency (EPA) says indoor air can be up to 100 times dirtier than outside air. Why?

Much of it has to do with modern construction methods, introduced in the 1970s, aimed at making homes more airtight, thus more energy efficient. This traps air and all its contaminants indoors. As more contaminants are added or created organically, the air gets thicker with them. Some of them can make some people ill. 

What’s in the Air?

Indoor air pollutants commonly include skin and hair cells from people and any animals in the house (aka “dust”); volatile organic compounds (VOCs) emitted by various plastics, adhesives, textiles, finishes and cleaning products. Also in the air are mold spores, mold parts and microbial volatile organic compounds (MVOCs) produced by mold. If there is mold growth in the house, these substances will continue to intensify.

Some molds also emit substances called mycotoxins. A good example is penicillin, the first antibiotic, which was derived from the mycotoxins of the penicillium fungus, a common mold. Most modern antibiotics are derived from, or based on, mycotoxins. Ironically, medical science knows little if anything about what those mycotoxins might do to people. But they know they’re deadly to bacteria.

As homes in the US became more airtight and energy-stingy, they also became more prone to moisture problems. Just as there’s no such thing as a waterproof watch (they’re “water resistant”), there’s no such thing as a waterproof house. Water will find its way in, either through leaks, plumbing failures, spills, or as water vapor that condenses when conditions are right.

With that invading moisture comes the rising probability of mold growth, and the risk of the indoor air becoming a far greater threat to health. Medical science has begun finding the links between indoor mold growth and our health, and doctors are beginning to recognize that home indoor air quality is a factor that must be investigated for their patients who don’t respond to treatment.

Mold assessment experts tell us that even blind spaces such as wall cavities, crawl spaces and attics can gain moisture via condensation, and mold can grow unseen. All mold needs is relative humidity of more than 50%, the same temperature range people can tolerate, and food, meaning anything organic, such as wood, paper, fabric, and even dust.

Mold and Illness

What kinds of ailments can be attributed to mold exposure? Not too may years ago, a knowledgeable person would have replied that there is no medical evidence of any connection. Not anymore. Mold is now implicated in a growing number of scientific studies as a possible, sometimes likely, culprit behind a host of illnesses, such as chronic sinusitis, asthma, even depression.

The Mayo Clinic in 1999 provided probably the first major medical evidence of mold’s role in disease. Mayo researchers found in a study that 97 percent of chronic sinusitis is caused by fungus. Said the Mayo Clinic in its press release:

"An estimated 37 million people in the United States suffer from chronic sinusitis, an inflammation of the membranes of the nose and sinus cavity. Its incidence has been increasing steadily over the last decade. Common symptoms are runny nose, nasal congestion, loss of smell and headaches. Frequently  the chronic inflammation leads to polyps, small growths in the nasal passages which hinder breathing."

“Up to now, the cause of chronic sinusitis has not been known,” say the Mayo researchers: Drs. David Sherris, Eugene Kern and Jens Ponikau , Mayo Clinic ear, nose and throat specialists. Their report appears in the September issue of the journal Mayo Clinic Proceedings.

“Fungus allergy was thought to be involved in less than ten percent of cases,” says Dr. Sherris. “Our studies indicate that, in fact, fungus is likely the cause of nearly all of these problems. And it is not an allergic reaction, but an immune reaction.”

The researchers studied 210 patients with chronic sinusitis. Using new methods of collecting and testing mucus from the nose, they discovered fungus in 96 percent of the patients’ mucus. They identified a total of 40 different kinds of fungi in these patients, with an average of 2.7 kinds per patient.

In a subset of 101 patients who had surgery to remove nasal polyps, the researchers found eosinophils (a type of white blood cell activated by the body’s immune system) in the nasal tissue and mucus of 96 percent of the patients.

The results, the researchers say, clearly portray a disease process in which, in sensitive individuals, the body’s immune system sends eosinophils to attack fungi and the eosinophils irritate the membranes in the nose. As long as fungi remain, so will the irritation.

It would be quite a few years before another major study found other links between illness and indoor mold exposure. In 2005 a European study found that children’s risk of developing asthma between age 1 and 7 more than doubled in a home that smelled moldy.

Then in 2007 Berkeley Lab and the EPA collaborated on two papers, one of which concluded that indoor dampness and mold increased the risk of respiratory illness, including asthma, by as much as 50 percent. The second paper reported that 4.6 million  of the nearly 22 million asthma cases in the US can be attributed to mold exposure and dampness.

William J. Fisk, Quanhong Lei-Gomez and Mark J. Mendell, all from the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), wrote the first paper, which concluded that indoor dampness and mold raised the risk of a variety of respiratory and asthma-related conditions by 30 to 50 percent.

“Our analysis does not prove that dampness and mold cause these health effects,” says Fisk. “However, the consistent and relatively strong associations of dampness with adverse health effects strongly suggest causation by dampness-related [pollutant] exposures.”

The second paper, by Fisk and David Mudarri of the EPA, used results of the first paper and added data on dampness prevalence to arrive at an estimate that 21 percent of current asthma cases in the U.S. are attributable to dampness and mold exposure.

“Of the 21.8 million people reported to have asthma in the U.S., approximately 4.6 million cases are estimated to be attributable to dampness and mold exposure in the home,” said the authors.

With the exception of the Mayo Clinic study, which identified mold in the sinus cavities of its subjects, most studies don’t even attempt to identify the mechanism by which mold might cause, or help to cause a mold-related illnesses. This is because most studies are statistical analysis, not hands-on clinical analysis as at the Mayo Clinic.

What Is It About Mold?

So what aspect of mold is dangerous? Is it the spores, or the MVOCs, or the dreaded mycotoxins? And the answer is: No one knows. Science has not progressed that far.

Still, mold assessment professionals like Jason Earle, founder of national franchiser 1-800-GOT-MOLD?, say they have seen lots of field evidence indicating it could be all three, depending on the circumstances, but that MVOCs are highly suspect.

MVOCs are what most people would think of as solvents and petroleum products. They include such chemicals as benzene, acetone, alcohol (a variety), methyl chloride, and on and on.  When mold is hidden in closed spaces such as wall cavities, its spores are usually not found in the air, yet sensitive people often become ill as a result – and get better when the moldy material is properly removed.

This strongly suggests that it’s the MVOCs doing the dirty work, because they are vapors that can pass through solid materials such as sheetrock, which would block particles such as spores.
What 1-800-GOT-MOLD?’s Mr. Earle says he has learned from experience with thousands of families is that a three-pronged approach usually solves chronic health problems:

  • Detect, locate and quantify the extent of mold growth and mold-affected areas, hidden or otherwise, using professionals equipped with dogs, infrared thermography and experience;
  • Diagnose and correct the source of excess moisture;
  • Eliminate any moldy materials using professional remediation contractors, supervised by a third party qualified mold assessment professional, and install dehumidification and air purification equipment recommended by an indoor air quality professional to keep indoor air contaminants at a minimum.
For more information about mold and how to deal with it, 1800gotmold.com is a good place to start.

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Medical Science and Mold
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