Battling Mold

An article on 25 ways (convenient number to stop on) to combat mold. There are some good points: don’t use bleach, find the source of the water.

The article ends with, “A mold-safe building is not a one-time effort.” Discouraging.

“Neither Plant Nor Animal”

Old news, new study. Beautiful pictures.

Research Frontiers article

Mold’s Effect on Individuals

Most commonly, molds affect many people by allergenic reactions. Symptoms include nasal stuffiness, eye irritation, sneezing, wheezing, and skin irritation. However, many people report more severe reactions to mold. These symptoms go beyond the basic skin and respiratory irritations to include fever, and asthmatic attacks. Chronic lung disease, such as obstructive lung disease, develop mold infections inside of the lungs. The 2004 Institute of Medicine found evidence to link upper respitory diseases to otherwise healthy individuals.

Mold in lungs.

More information available at Center for Disease Control.

Lovely Mold Article

Nothing this pretty could be bad for us..

Island Nature article.

Mold In The Arts

I was struck by the beauty of mold as a high school student. I would draw trees like molds on everything I owned. I got pretty good at it. Seems I wasn’t alone in finding mold beautiful.

Mold in the arts.

Mold Choir

In this photo it is easy to see how easily mold particles become airborne.

Photo by Dr. Steven Stephenson

Brown University Links Mold to Depression

This is something workers in the mold and waterproofing industry have know all along. It is a common observation that people that have moldy homes are more lethargic and depressed.

Brown study

The European World Health Organization

In October, 2007, European specialists met in Bonn in order to discuss the problem of microbial pollution. Indoor pollution is caused by hundreds of species of bacteria and fungi, but most particularly filamentous fungi—mould. The Guidelines for Indoor Air Quality: Dampness and Mould discusses the most recent scientific evidence on health problems caused from mould which concludes that exposure to indoor pollution causes increased respiratory problems, allergies, and asthma, as well as agitation of the immunity system. This document also discusses common conditions in which mould thrives  and ways to control it. The best way to avoid health issues due to microbial pollution is to prevent excessive moisture from accumulating visible or within walls and foundations.

European Health Minister at 60th regional meeting in Moscow (September, 2010)

More Information available at World Health Organization.

Mold And Allergies

This article discusses pediatric mold issues and symptoms.

Pediatric Mold Allergies

Why is Mold Growing in My Home?

In a natural environment, mold is part of the nature’s cyclical process. Mold works to break down organic material, which is great if you are creating homemade organic mulch for your garden. However, in your home, this is not necessarily a good thing. Mold reproduces by microscopic airborne spores. When these spores blow into the house and land on dusty surfaces or organic material (wood, paper, fiber, clothe, etc.), they continue to cultivate. Warm moist areas are best at culturing mold, but any form of moisture will work.

Wet conditions favor the development of fungal blights of tomato. Mold is everywhere.

(Photo available from ISU Plant Disease Clinic)

Information found at Environmental Protection Agency.

ScienceNews Mold Article

This article appeared in ScienceNews May 22, 2010. It discusses the similarities of humans and mold.

In the germ world, fungi usually lack the flair of viruses or bacteria. To people with normal, healthy immune systems, a fungus will rarely show itself — even though you carry around a microscopic film of fungus on your hair and skin, and take in invisible clouds of fungal spores with each breath. While many other microbes prefer to make a living through disease and death, a fungus is often content to wait for its host to die of something else.

In fact, throughout the history of civilization fungi have mostly been humans’ friends, providing the bounty of bread and beer, recycling trash and enabling plants to extract nutrients from the soil. Scientists estimate that roughly 1.5 million species of fungus inhabit the Earth, but only a handful are capable of causing human disease.

Problem is, when they do, fungi can be remarkably lethal: For example, about half the patients who develop serious infections from the fungus Aspergillus will not survive. The mortality rate for the most common fungal infection in hospitals, candidiasis, has been reported to be just as high — and though numbers are hard to come by, reports suggest overall fungal infection rates have been on the rise. Doctors have also recently become concerned about a once-rare infection from the Cryptococcus fungus spreading in the Pacific Northwest (SN Online: 4/22/10).

Understanding what transforms a fungus from pal to pathogen has occupied researchers for more than a century. Yet scientists have only recently discovered some key principles that govern how fungi operate, and that allow a normally peaceful fungus to turn against people. In trying to decode the molecular conversation between microbe and human host, fungus explorers have also found some surprising secrets about the human immune system.

“We’re now starting to see studies that rival anything else done before them,” says William E. Goldman, a microbiologist at the University of North Carolina at Chapel Hill. Since 2004, when the complete genetic blueprint of Candida albicans was published, researchers have cataloged the genomes of about a dozen species of fungus that cause disease. Studies of these genomes may soon reveal how fungi survive in people’s bodies — and suggest new ways to extinguish the germs. Scientists have also recently discovered families of molecules on human immune cells that alert the body to the presence of fungi and other invaders, as well as mechanisms that allow a fungus to evade those cells.

Taken together, these findings may soon solve one of the most challenging aspects of treating fungal infection: how to get rid of the germ that is your closest relative.

In old biology classes, fungi were lumped with plants, presumably because both forms of life could sprout from dirt. Today, fungi are recognized as their own kingdom, a diverse group of organisms that live in the inky depths of the ocean, the sub-zero snows of Antarctica and the forgotten apple in the refrigerator.

Fungi include mold, yeast, mushrooms and other growths that don’t make energy from chlorophyll and light. To reproduce, many fungi shed microscopic spores, each one capable of propagating. Even if you don’t see fungi, you live with them daily. A 2005 study found that about a million spores are nestled in your pillow alone.

Fungi are usually the vultures of the ecosystem, preferring food that is almost or already dead. (Aspergillus, for example, usually hangs around rotting leaves and compost piles, feasting on decaying matter.) But sometimes, when conditions are right, a fungus starts to germinate while its host is still among the living. In people, this generally leads to troublesome, but not fatal, infections of the skin and nails.

“Most fungal pathogens are pretty wimpy,” Goldman says. “They are not very good at causing disease in normal hosts with normal immune systems.”

But a growing population of people have not-so normal immune systems. Fungal infections are so deadly in part because most patients who become seriously ill are already weakened by AIDS, cancer, transplants or medications that handicap the body’s ability to mount a strong defense. More and more of these patients have taken high doses of anti biotics to prevent other infections, fundamentally changing the body’s ecology and allowing unnatural fungal growths to take over. More patients are also undergoing medical procedures that breach normal immune barriers with catheters and other devices.

While relatively rare a generation ago, candidiasis — a blood infection from the fungal genus Candida, which normally lives on the skin — has become the fourth most common infection acquired in hospitals. Although infections from Aspergillus are not carefully tracked, studies suggest that the number of deaths quadrupled during the 1980s and ’90s.

Drugs to treat fungal infections have been difficult to develop because fungi share many properties with people; from an evolutionary standpoint, fungi are closer to the animal kingdom than any other form of life. If you put mushrooms on your pizza, the mushrooms have more in common with you than with the tomato sauce. Fungi are also much more closely related to humans than are viruses and bacteria, which makes attacking fungal infection a tricky business.

Unlike other kinds of germs, both people and fungi are eukaryotes — among other commonalities, their cells have a nucleus, and the nucleus has its own membrane. In fact, fungal cells are so much like animal cells that much about the basics of human life has been gleaned from studies of baker’s yeast.

To fight infection, antimicrobial drugs often exploit some molecular difference between an invading organism’s cells and human cells. But with fungal treatment, human tissue is more likely to find itself in the line of fire. Although more modern antifungal drugs are less harsh than their predecessors, one of the first widely used antifungals — amphotericin B — had a reputation for being highly toxic.

“When we are evolutionarily so similar, it’s hard to get drugs that target fungi alone,” says Bruce Klein of the University of Wisconsin–Madison. Drugs that treat bacterial infections often aim for molecules in the bacterial membrane. However, if drugs attack fungal membranes, the treatments often hit human cells too.

There are, however, distinctions between human and mold. Most notably, fungal cells enclose themselves in a tough outer wall that shields them from abrupt changes in moisture and temperature.

“The fungal cell wall is the major difference between us and them,” says Stuart Levitz of the University of Massachusetts Medical School in Worcester. “But it can be their Achilles’ heel. It’s what protects them in the environment, but also what flags them as being different.”

The most important building blocks of this wall, at least to the immune system, are large glucose-based molecules called beta-glucans. In recent years, researchers have begun to compile a laundry list of receptor molecules on the surfaces of human immune cells that recognize and interact with the beta-glucan molecules from fungi. Receptors act as gatekeepers, linking the outside of a cell to its internal workings. By examining these receptors, researchers can eavesdrop on the molecular crosstalk between fungi and people.

Studies have found that just after fungi enter the body, defense relies mostly on “innate immunity” — a general, shotgun-like immune response that enlists certain types of white blood cells to find and destroy invaders. The other type of immunity, “adaptive immunity,” takes longer to kick in, involving specialized infection-fighting white blood cells known as T cells and the production of antibodies that confer long-lasting protection against a specific target.

While humans produce plenty of antifungal antibodies, innate immunity is thought to be the first responder against a fungus. This basic defense mechanism is found throughout the animal kingdom; even horseshoe crabs protect themselves from fungi using innate immunity.

Scientists speculate that one reason fungi don’t cause as much human disease as other microbes is because “our innate immunity has evolved very, very well so we’re able to recognize and respond to fungi by a variety of different mechanisms,” says Levitz. “Possibly as a consequence of that, the fungi have not evolved to become significant human pathogens to the extent that bacteria, parasites and viruses have.” (Plants have not been so fortunate; despite plants and fungi’s long and close interaction, fungi are significant plant pathogens that spoil about 10 percent of the world’s harvests each year.)

Among the most important type of proteins that recognize fungi are the toll-like receptors, so named because they resemble a similar fruit fly molecule called toll. As receptors, they switch on when they encounter proteins from fungi and bacteria, setting off other reactions inside the cell. A team of French researchers reported in 1996 in the journal Cell that flies with mutations in the gene for a toll receptor were unusually vulnerable to infection with Aspergillus. In human white blood cells, two toll-like receptors in particular — TLR2 and TLR4 — appear to be involved in the body’s fungus-fighting ability.

In 2008, scientists from the Fred Hutchinson Cancer Research Center in Seattle helped demonstrate the fungus-fighting role of TLR4 in a study in the New England Journal of Medicine. The researchers examined patients who had received bone marrow transplants and later developed Aspergillus infections. In general, about 10 to 15 percent of transplant patients will develop the life-threatening condition aspergillosis, but it’s not clear why the other 85 to 90 percent of patients escape unscathed.

The researchers discovered an inherited gene that causes a malfunctioning TLR4 in the patients who had become ill. Without a normal TLR4, the scientists proposed, these patients’ immune responses may have been weakened. Genetic testing for this mutation among blood stem cell donors may one day identify patients who need special care or attention following a transplant, the authors pointed out.

Two other reports in the New England Journal of Medicine last year described genetic flaws that caused increased susceptibility to fungal disease, confirming the role of other receptors in fungal protection. One involved dectin-1, a receptor first recognized as key to fungal defense in 2001. Dectin-1 partners with the TLR receptors to produce substances that both attack fungi and deploy other white blood cells to help fight infection.

Last October, an international team of researchers described genetic studies of one family in which otherwise healthy women seemed particularly prone to chronic Candida (“yeast”) infections of the vagina, fingers and toes. The researchers found an inherited genetic alteration that led to a defect in dectin-1.

A second team investigated another family whose members were prone to recurrent, and sometimes fatal, infections of Candida. A team led by University College London researchers found a different inherited mutation that made a person vulnerable to fungal infection. When dectin-1 detects the fungus, it sets off a chain reaction that gets immune cells in battle mode. A mutation can interfere with one link in that chain, a molecule called CARD9, the researchers found. In this case, dectin-1 was triggered correctly, but the mechanism jammed farther down the line.

While these and other discoveries have brought new understanding to how immunity works, much about how the human body handles its relationship with fungi remains unclear.

“The thing that’s most on my mind is how these organisms can manage to survive and proliferate in such a close relationship with host cells without triggering alarms,” Goldman says.

Stealth spores.
Goldman’s work focuses largely on Histoplasma, which can cause lung infections. These fungal spores grow inside white blood cells called macrophages — innate immunity cells assigned the job of destroying invading organisms like fungi. “Here is an organism that gets inside the very cell that’s supposed to be destroying them,” he says.

While the stealth tactics deployed by Histoplasma remain largely a mystery, scientists recently reported that Aspergillus may dodge the immune system by borrowing a tool from Harry Potter: a cloak of invisibility.

Though each cubic meter of inhaled air may contain a thousand or more Aspergillus spores, the immune system doesn’t seem to notice. Scientists had been unclear why. Then, writing in August 2009 in Nature, researchers from the Pasteur Institute and elsewhere offered an explanation: The body’s immune system can’t react to the spores because the immune system doesn’t know they are there. Normally, the spores are coated with a thatching of small fibers called the “rodlet layer.” In experiments with mice, the researchers found that the fibers alone do not excite the immune system. However, when researchers stripped the rodlets from the outside of the cells, the exposed spores invoked a robust immune response.

It appears that the rodlet layer may allow the fungal spores to hide in the body, waiting until conditions are favorable to germinate (such as death). The researchers also noted that when Aspergillus spores start to grow, the outer coating disintegrates and the immune system kicks in.

Scientists have recently discovered other deceptive feats. In the March 18 Nature, researchers revealed that members of a fungus genus that attacks plants are capable of passing off genes to one another — a lateral handoff thought to occur almost exclusively in bacteria. The discovery means fungi that develop genetic resistance to a drug treatment could theoretically share that secret with neighboring organisms.

The shocking thing, says study co author Michael Freitag of Oregon State University in Corvallis, was the ease with which fungi traded genes. Freitag and his colleagues simply put genetically distinct samples of the fungi side by side on a petri dish, incubated them together and tracked genetic movement. “It’s not that far removed from what would occur in natural conditions,” Freitag says. “I was surprised it would work that well.”

While no one knows whether other species of fungus are capable of sharing genes so readily, the findings reinforce the idea that nothing about fungi should be underestimated. To succeed in conquering infections, the next generation of treatment will need to hit several targets at once.

Freitag likens current antifungal treatments to the cancer treatments of the ’60s and ’70s, most of which were designed to target cells that grew rapidly, and not cancer cells specifically. Today, doctors have a number of drugs that can zero in on the specific defects of a malignant cell, and physicians prescribe drug cocktails that try to disable several mechanisms simultaneously. Fungal infections appear to have similar complexity, including sharing properties with nontargeted cells, and will require treatment just as sophisticated, Freitag says. “Just like now we can attack very specific targets in cancer,” he says, “we are going to have to do that with fungi.”

Article source:,_Mold

Testing For Mold

Are there reliable tests to indicate the presence of mold?

Almost all of us already have two effective mold detectors: our eyes and our noses. If black or green discoloration is noticed that is fuzzy in appearance and is in a location that is damp or had been damp, it is almost certainly mold. If a building smells musty, there probably is mold somewhere; the mold may be on boxes stored in a basement or in walls or in the crawl space. If you want to find mold, look for the presence of water or a location where water was likely to have been. If there is still any question about whether the black stuff is mold, have a reliable laboratory examine the material. All you need to know is whether mold is seen when the material is examined under the microscope.

An increasing number of companies are offering “air testing for mold.” On the surface this seems like a reasonable thing to do. The problem, however, is that the results of most air sampling for mold are meaningless for two reasons. Air sampling for mold was not developed to determine if an environment was safe or had a dangerous level of mold in the air. Air sampling was developed to help identify the location of a hidden reservoir of mold. If the source of mold is already identified, air sampling does not provide additional meaningful information. Furthermore, safe or toxic levels of air borne mold have not been established. An individual air sample for mold provides a “snapshot” of what was in the air during the few minutes of sampling. The results may not be indicative of the amount of mold that is in the air during most of the day.

Air sampling for mold should be done either to obtain an answer to a question that cannot be answered without the air sampling or to obtain data as part of a research project. The Center for Disease Control (CDC), the U.S. Environmental Protection Agency (EPA) and the American Conference of Governmental Industrial Hygienists do not recommend routine air testing for mold.

About the Author

Dr. Nathan Yost, MD is a Principal with the Building Science Corporation, a building and construction consulting firm. Over the last twenty years, Dr. Yost has been a home builder, and a medical doctor specializing in respiratory illness. NAR has hired Dr. Yost on a contractual basis to provide its members with information and analysis on the scientific aspects of mold and moisture issues. The information contained in this FAQ is strictly the opinion of Dr. Yost, does not reflect NAR policy, and should not be construed as medical advice.

Article source

Illinois Dept. Of Health article
Should I have my home or business tested for mold?

IDPH does not recommend testing for mold (see the fact sheet “Indoor Environmental Quality: Testing Should Not Be the First Step”). If mold growth is visible, testing is not needed to identify what type or level of mold is present. Mold testing also is not typically useful in determining what steps to take for cleanup.

If you can see or smell mold, testing is usually not necessary. It is likely that there is a source of moisture that needs to be fixed and the mold needs to be cleaned or removed. Even if testing is done, no standards or guidelines exist to judge acceptable amounts of mold. Testing cannot determine whether health effects will occur.

Article source

What Causes Mold Growth?

The primary cause of mold growth is water. Mold does need food such as paper, building products, paper, boxes, fabrics etc. but mold can also grow and feed on dust. Because of this mold can grow in an empty basement where there is only cinder blocks as in the images below.

This most important factor in mold growth though is water alone. This is because mold can grow on, yep, mold! If you remove the water supply the mold will die rather quickly, but if you remove the food (drywall, cellulose, fabrics etc.) the mold will still grow in the residual mold. This is but one of the reasons that mold remediation begins with treating the water intrusion.


Is the use of dehumidifiers a solution to interior moisture problems?

Honest answer. No.

Dehumidifiers pull moisture out of the air. If there is a moisture problem: AC condensation or imbalance, plumbing, roof or foundation leak, unsealed drainage system, foundation overpour, or any other issues causing interior moisture or dampness then these problems should be dealt with directly. If a space requires a dehumidifier then it has a definite moisture problem that should be addressed first.

Dehumidifiers will not remove puddles of water from a floor or dry out wet carpet and should only be used if other moisture prevention measures have failed.

Can Moldy Carpet Be Cleaned?

This is a very common question asked by homeowners that have experienced a flood.  Carpet is pretty easily cleaned and is made of mostly plastic fibers and plastic can not rot, but there are some materials that can. The answer is dependent on a few points.

  1. If the carpet has got to the point after to many wet/dry situations that it is actually brittle then it is not really salvageable.
  2. Did the carpet get really wet or just the pad. If it was mostly the pad then just pull the carpet off the pad and replace the pad.
  3. If the mold has stained the carpet a blackish color it may be possible to fully clean it, but it will not be possible to restore the original color.

And finally, is it really the carpet that is what smells? Sometimes cleaning the carpet does not remove the smell if there is wet or moldy drywall, furniture, boxes, luggage etc.

How Does a Basement Flood?

The most common point of entry of water into a basement is through the cove seem. This is the seam where the footer sits on top of the wall as show below.

This ‘cove seam’ where the separate sections (the footer and the wall) are poured at different times (the footer is poured first). This is the way all belowground foundations are built. The problem is that this always leaves a small seam where the two footer (first pour) and the wall (second pour) meet. As water stands outside the foundation as in the picture below, it penetrates through this seam. This is why most foundations are damp/wet across the entire wall floor seam (cove seam).

The problem in most finished basements is when you place drywall and framing on these same problem outside walls. It is a recipe for instant mold.

Water is a very small molecule (see Amazing Water). One of the smallest actually. Trying to seal these walls off with painting products or trying to dry out the rooms with standing water using dehumidifiers is not possible.

What Is Mold Remediation?

Mold remediation is often considered the removal of mold from walls, furniture etc. and this is correct, but there is more. The following article from NC State University outlines how resolving the source of moisture is the primary step to mold remediation.

The following was taken from the page

Factors That Produce Mold Growth

Although molds can be found almost anywhere, they need moisture and nutrients to grow. The exact specifications for optimal mold growth vary by the species of mold. However, mold grows best in damp, warm environments. The availability of nutrients in indoor environments rarely limits mold growth because wood, wallboard, wallpaper, upholstery, and dust can be nutrient sources. Similarly, the temperature of indoor environments, above freezing and below the temperature for denaturing proteins, can support mold growth, even if the actual temperature is not optimal (8).

The primary factor that limits the growth of mold indoors is lack of moisture. Substantial indoor mold growth is virtually synonymous with the presence of moisture inside the building envelope. This intrusion of moisture might be from rainwater leaking through faulty gutters or a roof in disrepair, from a foundation leak, from condensation at an interface (e.g., windows or pipes), or between a cold and a warm environment. Water also can come from leaks in the plumbing or sewage system inside the structure. Studies of mold growth on building materials, such as plywood, have found that mold grows on materials that remain wet for 48–72 hours (8). Flooding, particularly when floodwaters remain for days or weeks, provides an almost optimal opportunity for mold growth.

To summarize, mold remediation is not cleaning mold, but actually taking the steps to prevent any moisture from re-entering the molded area. This step of prevention can be attained by foundation waterproofing, repairing failed gutters or spouts, AC condensation problems, roof leaks, plumbing leaks. Rarely is ‘sloping the ground away from the house’ an adequate solution. The problem is nearly always in the ground not on the ground.

Mold Benefits?

There are many different types of mold, but not all of them are harmful. In fact mold is pretty helpful a lot of the time. Mold breaks down dead substances and deposits them back into the ecosystem. For example if a tree dies in the woods the mold would break it back down in to soil. Also we eat some molds such as mushrooms. Finally, molds help us create antibiotics such as penicillin and many others. Many say we could not live without mold. Although there are many ways in which mold helps us there are also many molds that are extremely harmful and should be taken very seriously.

What should you do when mold is discovered?

None of us want mold in our houses, but what do you do when it does show up?  Unlike many things mold is basically impossible to prevent. Just because it is impossible to  prevent, doesn’t mean you can stop it when it starts. Mold needs water to live so therefore you must eliminate it’s water source. Sometimes water comes from a leaky roof or a countless number of other things.

Fighting Gray Mold

As a gardener I have seen gray mold destroy plants that were once the picture of health. Destroying strawberries and potatoes that I had much better plans for. What can be done about this determined pathogen? Fungicides make me nervous and moldicides too. Brown University chemist David Cane now has an answer for us.