Fungi evolved over millions of years ago (Sherwood-Pike, 1985) and references to mold in buildings suggest that molds have always been present in human environments. At present, there is growing public concern about the potential health effects of mold in homes and structures that has been heightened by growing illness and bizarre weather conditions, inexpensive building materials, defective workmanship, and cutting corners; although extremists and those who benefit from false information would like you to think it is due to media reports and litigation. That is a fallacy and brought on by ignorance and propaganda, as will be further explained in this article.
There are a host of materials in and around the home that, under proper conditions, can become breeding grounds for mold. Molds can grow on organic materials such as drywall paper, wood panels, OSB, lumber and carpet, and backing. It may grow equally well on inorganic materials such as concrete, glass or plastics that may have nutrients and organic material on the surface. It has become apparent in all cases that the presence of moisture is a critical condition for the growth of mold.
Lumber is an organic material and a focus of many issues in regards to indoor mold contamination. In situations with adequate moisture, mold can become established on wood and this can become a starting point for mold to begin. Mold Help suggests coated lumber, treated against microbials.
However, in all cases involving mold, the underlying problems such as flooding or water leaks affect many materials in the structure, including lumber. But if products are pretreated, and this process can be done quite inexpensively and even purchased as such, it is the best purchase you could possibly make. The purpose for using lumber in this study, is that mold proliferates on lumber very easily and it makes mycotoxin-producing molds easier to explain to the layperson.
Why is there Concern About Mold in Homes?
Mold growth in homes has not necessarily increased in recent years, except for the increase of use of cheaper, more absorbent materials, but advocacy and awareness has certainly made its way into the industry. This has disrupted the influence on “crusade” on the ignorant; thus influencing the way that many “market” the entire mold problem. This has enhanced the entire “hype” and “hysteria” crusade on the part of defense physicians, insurance companies, and anyone else who has a financial interest in this field.
‘Hype’ and ‘Hysteria’
This is all false and any educated individual can see this, should they choose to.
First, there has been increased media coverage due in partly because of newly discovered evidence of the permanent neurological, pathological, immunological, and psychological damage that exposure to certain mycotoxin producing fungi causes.
The squalid insurance industry, in their efforts to avoid liability, is trying everything they possibly can to discredit the 40,000 documented peer-reviewed medical papers that demonstrate the severe health effects of fungal exposure fro reputable physicians world-wide. Their marketing tactics have been dramatic, succinct, and wide-spread. But the truth, however is prevailing, and even the insurance industry, the government, and many inept physicians are realizing that their half stacked house of cards is falling. It’s only a matter of time before the truth prevails.
Much of the recent concern about mold was aroused after several articles on the subject appeared in scientific journals. One of the most widely publicized articles was written by well-versed researchers or (‘spin-doctors’) from the U.S. Centers for Disease Control (CDC, 1994, 1997). They stated that in 1993, there were 10 cases of acute pulmonary hemorrhage/hemosiderosis in infants, some of whom died, that was claimed to be linked to the mold Stachybotrys chartarum (also known as Stachybotrys-atra).
This article caused great concern and spurred reactions across the country. However, upon a closer marketing plan of the study and its data and ‘conclusions’, a CDC focus group and an company they hired denied the initial findings to allegedly rebuff liability. Many groups rejected this as a racist plot since all 10 babies were African American and low-income. Both panels claimed there was ‘no evidence or scientific proof’ that Stachybotrys caused the health problems in these infants (CDC, 2000) although the infants were seemingly healthy and one epidemiologist allegedly quit as a result of this after this potential cover-up. Many called it a racial conspiracy and were very upset over this CDC blunder.
While the initial report of the CDC research was marketed, the revised findings received little coverage, and the public was greatly disappointed. As a result, there continues to be the misperception and great distrust on the part of the CDC as the damage had already been done, for great reason. The idea was already there that there is scientific proof Stachybotrys chartarum causes serious health problems in infants. In fact, the CDC now claims: “At present there is no test that proves an association between Stachybotrys chartarum (Stachybotrys atra) and particular health symptoms.”(CDC, 2000b). The bulk of the intellectual people believe otherwise as the damage had already been done. For several hundred scientific papers on stachybotrys chartarum, see our scientific data section.
Two other articles have influenced the concern about mold and health problems, specifically in persons who worked in office buildings. These studies proved to show a causal link between working in the buildings and symptoms such as neurological/cognitive problems, as reported in questionnaires (Johanning, 1996; Hodgson, 1998). The authors of these studies concluded that mold producing mycotoxins were the root of many major environmental health symptoms. In addition to the above studies, there are some widely cited anecdotal reports of acute, or sudden, health effects attributed to mycotoxins (toxins produced by molds) after exposure to extremely moldy conditions, depending on individual immune systems, exposures, and a multiplicity of other correlations of the moldy environments (Brinton, 1987; Croft, 1986; Di Paolo, 1994; Emanuel, 1975; Malmberg, 1993). In all of them, the individuals were exposed to different concentrations of mold spores and some recovered after they were removed from exposure. However, many required treatment of various types including antifungal therapy, Mold Diet, vitamin/supplement/enzyme treatment, and other various therapies.
Other symptoms, such as neurological symptoms, coordination/balance, memory loss, pathological disorders, immunological imbalances, and joint pain are definitely attributed to fungal exposure. These symptoms are very common with prolonged, direct mycotoxin inhalation and a separate, prescribed treatment is key to success in all cases
Cholestyramine, according to many specialists, is not a recommended option nor is it a means to lifelong recovery. Granted, it may be an option in some cases, but it is not a “cure-all” as it has been marketed by some and patients should use caution just because they have found a physician who is competent in treating fungal disease.
Treatment can be a very complicated regimen and not one treatment works for everyone; which makes mycotoxicosis very difficult to treat. However, there are several ways to relieve symptoms and reduce stress. In extremely rare cases, it can take as long as 30 years to fully recover from the effects of fungal exposure.
What Is Mold?
Molds are part of the fungi kingdom. Fungi are a diverse group of organisms that include a wide range of species from the largest mushrooms to the tiniest spot of mildew. Distinguishing features of fungi are the need to extract their food from the organic materials they grow on and the ability to reproduce by way of minute spores. Fungi are a part of nature’s recycling system and play an important role in breaking down materials such as plants, leaves, wood and other natural matter.
Mold is the common name for micro fungi. In order to grow, molds require food, suitable temperature (ideally between 70 and 85 degrees Fahrenheit), oxygen and moisture (Zabel, 1992). When these conditions are met, mold will grow and reproduce by creating spores that are released into the air. Molds are very adaptable and can grow even on damp inorganic materials such as glass, metal, concrete or painted surfaces if a microscopic layer of organic nutrients is available. Such nutrients can be found on household dust and soil particles. They are much more prevalent in today?s building materials and building practices used primarily in the United States in lower cost dwellings.
Conservatively, more than 100,000 species of mold exist in the world. At least 1,000 mold species are common in the U.S. (Hawksworth, 1999). It is estimated that molds and other fungi make up some 25 percent of the earth’s biomass. Most mold spores land on places unsuitable for growth and eventually die. A select few land on surfaces containing nutrients and where the moisture, oxygen and temperature conditions are right for growth.
Mold and mold spores are everywhere around us and have always been a part of our environment. The air we breathe is a virtual jungle of fungal spores. We routinely encounter mold spores as part of everyday life both indoors and outdoors. Spore levels may vary seasonally, but some spores are always present.
Why Does Mold Grow on Wood?
Wood is a biological material consisting primarily of cellulose, lignin and hemicellulose. These three structural polymers make up 90 to 99 percent of the wood mass and give wood its unique properties that make it an excellent structural material (Panshin, 1980).
The wood chips, and wood pulp imported from the Amazon rain forests bring with them their own varieties of mold spores. The climate of “deregulation” that has prevailed since the early eighties has favored the proliferation of new construction in which building codes requiring pretreatment of building materials with anti-fungal agents have simply not been adequately enforced.
This in turn has led to circumstances, which when coupled with “corner-cutting” structural defects, have led to the conditions which favor water intrusion that has all to often allowed the appearance of truly toxic levels of mold spores and mycotoxins, which are, in turn, capable of inducing serious diseases resulting from the presence of agents with the potential for damaging the human immune system, inducing allergies, gastrointestinal disorders, skin disease, neurological disease, endocrine disruption, birth defects, cancer, pulmonary, renal, hepatic, and general metabolic disorders. (Gray, 2002)
Wood also contains a variety of other materials, including sugars, starches, proteins, lipids and fatty acids. These materials are present in the storage tissues of the living tree and are essential for a variety of functions. Even after a tree is harvested, these materials remain in the wood and can provide the initial food source for mold fungi.
Mold fungi are rarely present inside a living tree because the bark provides an excellent barrier against fungal and insect attack. Once the tree is harvested, these protective effects decline and the many spores present in the air can settle on the surface and colonize the wood. Also, the food sources for mold — the stored sugars, starches and other compounds — are exposed when logs are processed into lumber. Much lumber in today?s market is imported from rain forests that is not treated without fungicides, which makes it much more inhabitable for fungal species to live in dormant conditions until given a chance to proliferate, especially in damper conditions in North America or when mixed with other chemicals to enrich its living conditions.
What Types of Molds Are Found on Wood?
Under the proper conditions, wood may be colonized by a variety of fungi (Davidson, 1935; Dowding, 1970; Kaarik, 1980). A recent study at Oregon State University revealed that Douglas fir sapwood was colonized by over 45 species of fungi within six weeks after sawing (Kang, 2000). Most of these fungi are common to many other materials, while a few were specialized and only grow on wood.
Molds and stain fungi are the most rapid colonizers of freshly exposed wood. Both fungi discolor the wood and are almost indistinguishable from each other to the naked eye. Molds are typically characterized as fungi that discolor the wood surface through production of pigmented spores that can be yellow, green, orange, black and an array of other colors. The discoloration seen with molds is usually confined to the wood surface. Stain fungi discolor the wood more deeply and are not as easily removed. These fungi may produce some discoloration as they grow on the wood surface, but the primary changes occur as they grow deeper into the wood. Stain fungi darken as they age. This darkening creates what is called “blue stain” in the wood (Zink, 1988). Stained wood can experience minor losses in physical properties, but, like molds, the primary changes are in color and the increased ability to absorb liquids (Lindgren, 1952).
Decay fungi may also grow when wood products are exposed to chronic moisture. Decay fungi attack beyond the surface of the wood into the structural polymers of the fiber, reducing its strength. Decayed wood may be discolored, but spores of the decay fungus are not typically found on the surface. Spores of most species are produced on more complex fruiting structures that can produce billions of spores. Generally, decay fungi invade wood in structures after prolonged exposure to moisture, such as what occurs with plumbing leaks or seeping from outdoor water sources.
Many of the molds and other fungi that grow on wood are found on almost any material containing sugars or starches, including plant leaves, bread and other foods. They can grow on a microscopically thin layer of organic material, even forming on common household dust.
These fungi have evolved to rapidly colonize a substrate and utilize the stored sugars as quickly as possible, but they lack the ability to cause significant effects on the wood structure. The most common effect of mold attack on wood is an increase in permeability, which can lead to an increase in moisture or paint uptake (Lindgren, 1952). This is neither “hype, nor “hysteria.”
How are Molds Identified?
Mycology is the scientific study of fungi. Proper identification of molds requires that the person examining the fungi have extensive professional training in mycology. Although some species produce distinctive structures or colors, it is nearly impossible to identify the fungi present on wood with the naked eye. The identification of fungi from a sample using a microscope can take a few days or several weeks. This has been a recognized science since the 1800’s; hardly “hype” or “hysteria.”
Most mold and stain fungi are identified by the spores they produce and the structures on which they are produced. Samples can be taken by smoothing a piece of clear tape on the wood surface, then mounting the tape on a microscope slide. Another approach is to cut small pieces from the wood surface, then place these on a nutrient media. Fungi growing from the wood onto the media are then examined under a microscope for spores and other key identifying features.
It is important to note that finding mold does not provide information about the possible exposure to mold, or the risk of health effects from mold. The airborne mold spore concentration, or possible exposure to mold, cannot be calculated from the types and quantity of molds found on surfaces.
Individuals who inspect and test homes for mold should have the appropriate education and experience. A certified industrial hygienist (CIH), or approved and certified MH? mold testing professional with experience in sampling for molds is qualified to inspect a home for the presence of visible mold, and to collect samples for mold and to help with interpretation of the results. Industrial hygienists have training in exposure assessment and methods of controlling exposures to molds and other dusts. They can also provide advice on how to control exposure and contamination during clean up of mold.
The Mold Help Organization sets approval ratings for certifying testing professionals, hygienists, and remediation companies These standards require at least a CIH to have an accredited bachelor’s degree with a minimum 30 semester hours of science and specific industrial hygiene coursework, a minimum of four years of professional level-1 industrial hygiene experience and successful completion of a comprehensive one-day examination.
Testing professionals must have all completed coursework with a recognized and approved program that provides them with the knowledge, skills, and abilities to effectively and thoroughly test and write an abatement protocol to meet the needs of today?s consumer in 12 key areas to a 10 part testing regimen. Remediation contractors must all have completed applicable training, be licensed, bonded, and have full working knowledge of household mold, methodologies, and effective strategies to uphold the work ethics that exceed the demands of today?s consumer.
Each company will have a complete background check, including credit history, criminal background, and business license history. There will be a variety of methodologies; however, the four star rating and technical write-up will assist consumers in finding the right match. Resources will be rated on several factors, such as quality, background, safety, value, and qualifications. There will also be a strictly monitored process where previous consumers may write in and make comments and recommendations. This is the only way that fraud, waste, and abuse can be avoided in a rapidly changing industry with propensity for customer exploitation.
What are ‘Toxic Molds’?
This is somewhat of a misnomer. Some molds are referred to as ‘toxic molds’ because under certain conditions, they can produce mycotoxins. Mycotoxins are compounds “produced by fungi that are toxic to humans or animals and have economic impact.” (Ciegler, 1980). Many common molds can produce mycotoxins, thus the name should appropriately be called mycotoxin producing molds as apposed to ‘toxic molds’. Those that arbitrarily have been cited as ‘toxic molds’ including Stachybotrys chartarum (or atra), Chaetomium, various species of Aspergillus, Fusarium and Penicillium.
Mycotoxins are secondary metabolites. This means that the mold does not need to produce mycotoxins to grow or survive. Mycotoxins are produced only when certain environmental conditions are in place and when produced are found in extremely small quantities on a per-spore basis. Mycotoxins are contained in the spore itself and also may be found in the substrate or material in which the mold is growing (Jarvis, 1986).
The isolation of a mold type that has shown to produce toxins (“toxigenic” species) does not substantiate the presence of mycotoxins (Ren, 1999). For example, known mycotoxin-producing strains of Aspergillus flavus and A. fumigatus were grown on various building and construction materials. No mycotoxins were found in extracts of densely colonized ceiling tiles, wallboard, wallpaper and air filters. These negative results were obtained even with enhanced growth when the indoor construction and finishing materials were supplemented with carbon and nitrogen (Tuomi, 2000).
Mycotoxins are relatively large and heavy molecules (Schiefer, 1990; WHO, 1990). This means they are not volatile and do not evaporate from the mold spore or substrate particle. The musty odor associated with mold comes from volatile compounds generated as the mold reproduces (Pasanen, 1996). These compounds, which are different from the mycotoxins, may be annoying and irritating, but are not mycotoxins and are not highly toxic.
The concentration of the volatile organic compounds (VOCs) is usually too low, even in damp and moldy buildings, to cause sensory irritation symptoms such as burning eyes and upper airway irritation (Pasanen, 1998; Korpi, 1999). However, the odor of these compounds may be noticeable at levels well below the concentrations that might result in sensory irritation (Pasanen, 1996; 1998).
What is Stachybotrys?
Stachybotrys is a mold that grows well on chronically wet cellulose material. Outdoors, Stachybotrys typically grows on and breaks down dead plant material. In research conducted by Oregon State University, none of the 45 different species of fungi that formed on samples of Douglas fir sapwood were Stachybotrys chartarum (Kang, 2000). Stachybotrys chartarum and Stachybotrys atra are two different scientific names for the same mold. Indoors, it can grow on chronically wet cellulose building materials such as lumber, wood panels, drywall backing, insulation and ceiling tiles. Moisture contributing to indoor growth of Stachybotrys is usually provided by flooding or leaks. Left wet, the spores of Stachybotrys are not easily released to the air. However if allowed to dry, the spores may become airborne and can be inhaled.
The dubious CDC article and well regarded scientific papers that have directed much attention to Stachybotrys. These studies provide quite specific scientific evidence of an Stachybotrys exposure and the link between the permanent neurological, pathological, immunological, and psychological health effects that this mold can cause even altering DNA synthesis and cell replication. There are anecdotal case reports that state direct contact and exposures to low concentrations of Stachybotrys can result in symptoms of skin rash, coughing, chest tightness, bloody nose, fatigue, nausea, vomiting, memory lapse, joint pain, miscarriage, and onset of autoimmune disease — and in rare cases — lower white blood cell counts. These symptoms are also reported to cease after the individual is no longer exposed to some symptoms. This is all documented science; no “hype,” nor “hysteria.”
What are the Possible Health Effects of Other Molds?
Humans are exposed constantly to molds in the environment, whether indoors and outdoors. Our immune systems and respiratory clearance systems normally provide defense mechanisms that protect us from health effects of airborne molds. Mold infections are possible in all people, despite the ‘hype’.
Many people are allergic to molds, but this is a big misconception that many “mold-negators” bank on. Allergic responses include hay fever and asthma. The molds that we are discussing can produce volatile organic compounds (VOCs) that can be irritating when present in high concentrations and can cause a number of symptoms that can also lead to some serious associated illnesses.
Routes of exposures to mold include dermal (skin contact), inhalation and ingestion. The route of exposure has a profound effect on the dose, or amount of material or toxin absorbed by the body (toxin can be absorbed a number of ways).
Dermal exposure to mold occurs when the skin is in contact with mold spores. The spores do not pass through the skin, but may cause irritation if there is contact with large amounts of spores or moldy material (Dobrotko, 1945). The irritation may be from reaction to allergenic compounds or chemicals, including mycotoxins, and possibly from rubbing against the spores themselves. Skin is generally a good barrier against particles.
Since mycotoxins stay with the particles, the skin is not a significant route of exposure for mycotoxins. However, Aspergillus has been known to cause a number of skin ailments. If you send us a confidential contact, please indicate if you know or believe you were exposed by Aspergillus, the genus/type, and what type, if any symptoms you may be exhibiting. We have resources that may be able to assist you with this and are conducting research in this area.
Mold spores or particles that become airborne can be inhaled. Bigger particles are stopped in the upper airways of the nose or mouth, and in the trachea and bronchi. Generally, only the smallest particles — those smaller than 5 microns — are able to reach the lungs. Stachybotrys spores can be less than 3 microns in size.
Although mycotoxins can be inhaled, mold spores are small and the amount of toxin in each is tiny. For most people, the airborne concentration needed to get to a toxic dose is in the range of many hundreds of millions of spores per cubic meter of air.
Ingestion is a more direct exposure route for mold. Historical incidents of mass human poisonings from molds have always involved the eating of moldy foods (Hudler, 1998). Through ingestion, a much larger mass of mold — and any mycotoxins present — can be taken into the body as compared to the inhalation route. Inhalation, however, is very common and less information is being presented on this.
Framing lumber in a newly finished house is typically encased by panels or siding on the outside and drywall or panels on the inside. As such, there is virtually no chance for occupants in a home to be exposed to any mold on the wood through skin contact or ingestion unless it gets wet or there is relative humidity of 55% or higher, which can be rather likely, depending on where one might live.
Inhalation exposure to mold on framing lumber in a finished home is possible, but not very likely. Mycotoxins are not volatile, so they cannot “off-gas” into the environment or migrate through walls or floors independent of a particle. Since particles cannot move through solid objects, mycotoxins in molds contained inside a wall or floor cavity will stay there unless disturbed. But again, other conditions can offset such problems, so beware.
Where is Mold Found in Buildings?
The presence of molds in our everyday environment means they can grow anyplace under the proper conditions. In all cases, moisture is the essential element for mold growth in buildings.
There are many potential sources for unwanted moisture in buildings. For example, improperly maintained air conditioning systems that create excessive condensation can be a breeding ground and distribution mechanism for mold particles.
Mold growth may be found in walls, ceilings and floor cavities when standing water is produced in a building or gets in and stays for more than a few days. Sources for water to support molds and other fungi in homes include plumbing leaks, gaps in roofs, siding or masonry, poorly sealed windows, porous slabs and foundations, inadequate drainage, and faulty roof drains and downspouts.
Poor ventilation and/or air circulation combined with high indoor humidity from showers, cooking or other activities can result in condensation that promotes mold growth on cooler surfaces. Poorly insulated walls may also provide a surface for condensation and mold growth in buildings that do not have general humidity problems.
Surface moisture on unseasoned framing lumber, appearing as the wood dries, may create conditions for mold growth. However, once the moisture content of the wood falls below 20 percent, mold growth can no longer be supported. Depending on the climate, framing lumber will dry to below 20 percent moisture content during the construction and before the building is enclosed. In instances where wood is chronically exposed to water, wood decay fungi can invade. Decay fungi can penetrate more deeply and attack the structural polymers in the fiber, reducing the strength of the wood.
Other conditions can increase the amount of mold spores in the indoor air of buildings. Homes with exposed-dirt crawl spaces and basements tend to have more airborne mold spores than homes without (Lumpkins, 1973; Su, 1992). With the right humidity conditions, some molds can grow on house dust. It is not surprising, then, that poor housekeeping and high indoor humidity are both associated with increased levels of airborne mold spores (Solomon, 1975; Kozak, 1979).
The biggest source of indoor mold spores is often the outdoor air (Solomon, 1975). Higher levels of indoor mold spores tend to be found in homes with yards having dense and overgrown landscaping (Kozak, 1979).
Indoor mold levels are generally lower in buildings with forced-air heating systems (as opposed to window ventilation) and lower still when these systems include a well-maintained and properly functioning air conditioning system. This is especially true if they contain a MH Seal of Approved UV-178 System that treats mold spore levels in the home. Because outdoors vary with the season and weather. They may be very high in the growing season or approach zero when snow overs the ground (Solomon, 1975). Except for the snow-cover situation, mold spores in normal indoor environments are usually between 20-50 percent of the outdoor levels.
Do Mold Spores Move from Inside Walls or Floors into Living Spaces?
Mold spores may be present in a home but out of sight inside a wall or floor cavity. This mold may have grown during construction and, with the wood dry and moisture gone, be dead or dormant. It may also grow after a leak has been repaired.
There is a lot of research about whether such “hidden” mold can move into the structure and increase the amount of mold spores in the indoor air. It does. During warm weather months, it is always wise to keep windows open and allow ?fresh? air in, although it is wise to know that mold is ubiquitous and even outdoor air contains trace amounts of spores. This is why a testing professional will always test the outdoor air at first to obtain a baseline level. It is the only way to know what is considered ‘normal’ or acceptable for that particular air quality.
The Wisconsin Department of Health and Family Services investigated the relationship between mold on surfaces of oriented strand board siding and mold levels inside the home. The results of the study indicated mold levels in the affected homes were not significantly higher than those measured in non-exposed homes (Dagger, 1999).
How Can Mold on Lumber be Prevented?
All fungi have four basic requirements for growth: suitable temperature, oxygen, food and moisture. Eliminating one of these required elements can prevent fungal growth (Scheffer, 1940; 1973). Mold fungi have fairly broad temperature requirements but most grow best at temperatures between 70 and 85 degrees Fahrenheit.
Most fungi require oxygen to function. In fact, one method for preventing stain and mold in wood is to submerge it in fresh water, which fills the wood cells with water and limits the availability of oxygen. Lumber and wood product mills often utilize this method by spraying log decks with water or storing logs in ponds at the plant. “Use coated lumber that has been protected with anti-microbials so you won’t have the problem to begin with. It’s cheap, easy, and safe,” says David Berg, building inspector from Ramsey Industry. Coated lumber is probably the most innovative, proactive and low cost step to avoid fungal problems in the future. Kiln dried wood, although once popular, has since become too expensive for most homes.
The lumber industry is probably the most reckless and liable when it comes to the end product. Lumber should not be stored in lumber
yards as it once was when it was once was as a kiln dried product. The average hardware store haphazardly stores lumber and in some cases trim woods outside, exposed to all types of elements, lending it to formidable types of fungal growth before many projects are even started. To better prove this point, look under your crawl space, or under the eaves of an outbuilding and some garages. In many cases you will see speckled black marks; generally the onset of fungus from storing untreated wood outside in some lumberyard. These types of mold, as many generally misunderstand it as a mere annoyance, call it ?lumberyard mold.? Lumberyard mold, as many experts will tell you is a valid concern as it can become a very severe problem should the wood ever become wet, releasing the spores and mycotoxins. The mold would then be brought from a dormant stage to a mycelial stage, and continue to grow and reproduce, releasing spores and mycotoxins along its way.
However, the average consumer, in their methods to get the most bang for their buck when building a home, generally think about aesthetic amenities, not avoiding future catastrophes from happening five to ten years down the road. The American society is a generally reactive population as opposed to proactive. Rather than conduct annual maintenance inspections for potential water intrusion problems, most people are spending their disposable income on fashionable upgrades that may add curb appeal, then react when an unsightly roof leak or pipe burst occurs. The average American homeowner needs to begin a new trend of thinking; the homes of today may not live out a typical 30 year mortgage if they are not inspected on at least a 2 year basis for safety maintenance. Simply said, the materials and craftsmanship in today?s average American home is not nearly what it was 100, 75, or even 50 years ago; people need to become aware of that.
While controlling temperature or oxygen is generally not practical for wood products, it is possible to remove moisture as quickly as possible during manufacturing. Reducing the moisture content of lumber to less than 20 percent will significantly decrease the opportunities for mold to form on the wood. Drying lumber reduces the likelihood of mold formation. But it does not guarantee the wood will remain free of mold. Lumber that is exposed to moisture after it has been dried will support mold growth. Dry lumber can become wet through direct sources, such as rainfall or condensation. Even dry lumber contains some moisture. So, wet pieces inside wrapped bundles of lumber could create conditions for mold growth. Exposing the bundle to direct sunlight, for example, could heat the lumber and the wrapping may trap the evaporating moisture. This trapped moisture can be sufficient to support mold growth.
Each year, billions of board feet of lumber are sold as unseasoned, or green products and are allowed to dry naturally, usually during the framing stages of building a house, which is the cheapest method and the main reason for mold problems in homes. Some mills reduce the risk of mold and stain on green lumber by applying anti-stain, or sap stain treatments, which are coatings of fungicides on the wood surface. These fungicides are applied by dipping entire bundles of lumber into a treatment solution or by spraying all four surfaces of individual boards (Scheffer, 1940).
Most of these chemicals are designed to provide a microscopic barrier against fungal attack that lasts for three to six months, depending on the chemical, the concentration used, the wood species and the climatic conditions. The old chemicals used for preventing mold and stain are usually very mild and include many used on food crops as well as in shampoos and paints. These old coatings are not recommended for long term use.
A new coating however has been designed that contains polymer binders in a resin system that penetrates untreated wood for longer-lasting protection. It is presently being considered for our prestigious MH Seal of Approval. More information on this product may soon be available.
When Should Mold be Removed?
Visible mold growing on surfaces where people may come in contact with it should be cleaned and removed. The decision to remove mold from enclosed cavities must be made after considering how much mold is likely to be present and how likely it is to be opened or disturbed.
In some cases, wood can simply be treated for mold growth with an antimicrobial solution, then dried and sealed. Caution should be used when disturbing spores and mycotoxins as this can exacerbate the situation and cause compromised individuals to become increasingly ill. Special equipment should also be used (see below). Where mold is present in existing structures, there are often reasons for opening walls and removing building parts that are unrelated to mold growth (such as for repairing warped and water-damaged floors or walls). In buildings where mold removal from enclosed cavities is not desirable or feasible, sampling can be conducted to monitor the level of mold spores in the occupied spaces. Negative air is recommended where applicable to direct loosened and remaining spores outside.
The process of removing mold from enclosed spaces could increase exposure to spores in the short term. High indoor mold spore levels are sometimes found when walls and floors containing mold are opened or disturbed, and when visible mold growth is present on exposed surfaces.
Can I Clean the Mold from Wood?
The decision to clean mold from lumber depends on the amount of mold present and how likely it is to be disturbed. In nearly all cases, mold cleaning should be undertaken only after any moisture problems are resolved. For any mold clean up, basic personal protection equipment such as rubber gloves, eye protection and a high-quality pollen or dust mask should be worn. There are a number of products on the market, from commercial antimicrobials to soap, which are promoted for removing mold from wood. However, there has been a lot of misinformation lately regarding products that claim to ‘kill’ or abate mold but lack any evidence to back up their claims.
If there is no laboratory or peer-reviewed material (against the major mycotoxin producing molds) regarding a product designed to clean up mold, the chances are that it doesn’t exist. Mold Help is in the process of setting ethical guidelines for such products and services to avoid consumer fraud and misinformation. Shortly, we will be making a valuable resource guide available to the public with a rating system. Each resource will have a complete background check, laboratory testing, and evaluation based upon value, safety, and product efficacy.
For cleaning wood surfaces, the EPA recommends wet vacuuming the area, wiping or scrubbing the mold, after drying, vacuuming with a high-efficiency particulate air (HEPA) vacuum (EPA, 2001). The molds seen on lumber are largely a collection of fungal spores on the surface of the wood. As such, wet wiping or scrubbing the lumber will remove the mold.
Simply wiping the wood, however, can release those spores into the surrounding air. A better approach is to gently spray or wet down the mold prior to removal. Once the mold has been wetted, it can be removed by wet-wiping the surfaces with a water and detergent solution, scrubbing if necessary.
Many experts has since negated this method, however, as water simply assists in proliferating spores. Some laboratory tested products can actually do a better job, if they can destroy fungal properties. If commercial products are used for cleaning mold, be sure to follow the manufacturer’s instructions for use.
Bleach and water CDC/EPA recommendation
Common bleach and water have both been recommended by both the CDC and EPA and it is important to note that this is not advisable by any means, despite the famous status of these government agencies. It has been suggested by health rights advocates that it may be a marketing approach to lend a benign value to this national health crisis. Regardless, it is ruthless advice.
In a 2001 report by the CDC, it states; Bleach (in addition to water) can also be used, particularly to clean the discoloration caused by mold fungi. The U.S. Centers for Disease Control (CDC, 2001, EPA, 1999) recommends using a solution of 10 parts water to one part chlorine bleach to clean mold from surfaces (CDC, 2000b).
The major reasons bleach should not be used to abate mold:
- It is too diluted and thus too weak to permanently kill mold unless the mold is simply sitting on top of a hard surface like a countertop or sink.
- What little killing power chlorine bleach does have is diminished significantly as the bleach sits in warehouses and on grocery store shelves or inside your home or business [50% loss in killing power in just the first 90 days inside a never opened jug or container] Chlorine ions constantly escapes through the plastic walls of its containers.
- Chlorine bleach’s ion structure also prevents chlorine from penetrating into porous materials such as drywall and wood— It just stays on the outside surface, whereas mold has protected enzyme roots growing inside the porous construction materials.
- When you spray porous surface molds with bleach, the water in the water solution soaks into the wood while the bleach chemical sits atop the surface, gasses off, and thus only partially kills the surface layer of mold while the water penetration of the building materials fosters further mold growth.
- Chlorine Bleach is NOT registered with the EPA as a disinfectant to terminate mold. You can verify that important fact yourself when you are unable to find an EPA registration number for killing mold on the label of any brand of chlorine bleach.
- Removing small amounts of mold from wood is relatively straightforward. Mold removal becomes more complex when there are heavy amounts of growth on a majority of the lumber or if the building has been in service for some time and the mold originated from leaks into the building cavity. In these instances, the mold clean up should be done by a Mold Help Approved remediation/restoration company. These will soon be announced but conducting your own research in the interim should suffice if you need to.
Once I Clean the Mold, Can It Come Back?
Mold spores are present on surfaces in all homes, so cleaning will not prevent re-growth of mold. Even if a building is stripped of all components and every spore is killed or removed, normal background mold spores from outdoors or on replacement parts have the potential to grow.
The most important objective in any mold removal is to remove or repair any sources of moisture. Should the wood framing in a house become wet, through leaks or flooding, it is imperative that the area be dried as soon as possible. In many climates, this drying will occur naturally once any standing water is removed. In other climates where the relative humidity is higher, it may be necessary to bring in portable fans to increase airflow or to use the existing heating system or portable electric heaters to encourage faster drying.
Are There Mold Regulations?
The U.S has failed to establish any regulations or exposure limits for molds or mycotoxins. This is true for homes, occupational settings, schools, stores and other public buildings.
Why Are there No Regulations?
This is an ideal marketing campaign, as many experts believe. If the government doesn’t recognize the problem, it doesn’t ‘exist’ in the eyes of the American public. This is quite the contrary.
When George Bush was in the Governor?s Mansion in Austin, Texas, there was a mold problem. It was quickly remediated at the cost of $300, 000 by the taxpayer’s money. In 2004, the Whitehouse had a mold problem, which too, was remediated at the taxpayer?s expense for an undisclosed amount. But these were extreme circumstances. This exception cannot be made for everyone for economic reasons. However, for those who claim that mold is all ‘hype’ and “hysteria,” you cannot help but ask yourself, why would the government go to such extremes for their high level executives?
The Cost of This National Health Crisis – What if?
The hypotheses are that the problem has become so substantial and precarious that the United States Government can not and will not accept responsibility for the liability issues alone. Exposure to some, potentially quite widespread household mold has been proven to cause permanent psychological, immunological, pathological, and neurological damage. The same T-2 mycotoxins, according to U.S. Army documents that have been used in biological warfare agents, cannot possibly be safe in one?s home, and even the government cannot pretend to be that ignorant. If any government agency were to admit the truth of the destruction that household fungal exposure causes, they realize that they would be bankrupt within an estimated 250 days of any such press release for numerous reasons.
- Due to the amount of gravely ill residents in low-income, government subsidized housing, students and school personnel in the estimated 70% of moldy schools nationwide, prisoners in the 89% of moldy prisons, military personnel, family members, and government workers on the estimated 70% moldy military bases, military housing, and moldy government buildings worldwide. There are also other severe ramifications that would heavily impact the medical industry. There are already a record number of denial claims for Worker’s Comp. associated with fungal exposure.
- For years, most physicians, although well educated in viruses and bacterial infections, have little to no education or skill in identifying, diagnosing or treating many mycotoxin-producing fungal infections. Most ‘traditional’ American medical professionals have knowledge in listening for key words and blurring out, thus not listening to important clues, to the rest of many crucial symptoms complaints that fungal infected patients cite when they go on about the multiplicity of that many suffer. End result, physicians are trained to prescribe medications to treat or mask symptoms, which does nothing for the problem at hand. Some inept physicians are so obsolete in their education that they actually deny that mycotoxicosis exists. Thousands of patients who suffer from chronic asthma, acid reflux, migraines, ‘allergies’, digestive problems, memory loss, fibromyalgia, cancer, Rheumatoid Arthritis, multiple sclerosis, etc., additionally suffer from fungal exposure; and there problems could be much more severe. But unfortunately, their physician?s ignorance has kept them from obtaining the proper medical care that they so desperately needed, possibly from causing more damage. If there were regulations, the medical industry would have to admit this gross error and the medical malpractice and wrongful death suits would mount into the billions upon billions of dollars, crippling an already handicapped industry.
- Additionally, if there were governmental regulations and exposure limits, the cost to test and remediate its own buildings would be insurmountable. This would cost jobs, reduce the government’s budget to a deficit that would be in excess of $500 billion.
It is obvious there was a “hype” and “hysteria” marketing campaign aimed at ignorant people when you read these numbers.
In the occupational setting, the general duty clause may apply to mold exposures. This is the rule that requires employers to provide workers with a safe and healthy work environment. Because there are conveniently no exposure limits for molds, there are no “benchmarks” with which to compare exposure measurements.
Typically, as mentioned previously, measured indoor airborne mold levels are compared to outdoor concentrations. Differences between the types and numbers of molds indoors vs. outdoors can provide clues as to whether the exposures indoors are above the background level and whether there is a source of mold inside the building. However, these data usually cannot be used to determine if exposure levels are safe. In most cases, air sampling for mold is not needed to assess or remediate a mold problem.
Molds play an important role in nature by breaking down organic materials. We routinely encounter mold spores as part of everyday life, in both outdoor and indoor environments. In most cases, the body’s immune and respiratory systems normally provide defense mechanisms that protect it from health effects of regular exposure to molds.
Inhalation of molds can result in a range of health effects in some circumstances. Infections are possible healthy people, despite the confusion regarding so called allergies. Many molds cause allergies. Allergic responses to molds include hay fever and asthma, and many people with allergies are also allergic to mold. The amount of mold that must be inhaled to cause an allergic response is unknown.
However, the properties in some common household molds produce mycotoxins (T-2 toxins) which are the same properties in biological warfare agents. Toxic effects from inhalation of mold may occur in situations where there are prolonged exposures to high airborne mold concentrations; however, since the Government has failed to establish guidelines or standards, there is no way to determine any ?safe? levels. Case studies have revealed prolonged exposure is contingent in many factors. This is why it is so difficult to determine. Pathological fungal types, spore counts, individual immune responses, bacteria balances, and individual health conditions. These mold concentrations have not been reported to occur in residences with mold enclosed generally in finished walls, floors, carpeting, and defective windows.
Lumber is just one of thousands of materials that can be a potential growth substrate for mold under the proper conditions. In a vast majority of cases, mold problems in homes are related to flooding or water leaks that affect many materials in the structure. Moisture is essential for mold growth and controlling moisture offers the best protection against mold. While all wood contains moisture, mold growth is not supported on wood dried to below 20 percent moisture content. Lumber used in construction will typically dry to below 20 percent moisture content before the structure is enclosed.
Drying lumber does not guarantee the wood will remain free of mold. If lumber is exposed to moisture after it has dried, it can provide a surface for mold to grow.
Mycotoxin producing molds are the number one health crisis of this century, potentially affecting an estimated 40 million people (Vojdani 2004). Thousands of families have lost their homes, health, life savings, and homes to this health hazard. Due to the avoidance of any governmental agency intervention, people are alone to face this senseless tragedy on their own. It is also impossible to know what research the Government has done in preparedness for this urgent situation, if any. Awareness, prevention, maintenance, and education are the key elements in avoiding this hazard. Ignorance should be avoided at all cost. This is what has fueled the entire “hype” and “hysteria” ideology, at the cost of thousands of lives. This is not funny, nor is it exaggerated. This is a national epidemic that needs to be addressed at an individual level if at all possible.
Lastly, we must re-enforce the fact that there are several industries that stand to lose billions upon billions from this hazard, as well. Ignorance on the part of the public would be most desirable because the bulk of liable is best left in the hands of the consumer, as opposed to:
- Insurance companies,
- Real estate professionals,
- Mortgage brokers,
- Land developers,
- Sellers of real estate
- Product manufacturers
- Retail suppliers
- and other possible responsible parties.
Therefore, the mystery behind the mold ‘hype’ and ‘hysteria’ is quite simple. It is a marketing ploy cleverly operated by the industries that have the most to lose. What you most likely see is the Mold ‘Hype’ or that it is nonsense. The industries’ crusade to keep the public ignorant is nonsense. We believe the public is more intelligent than this.
We’ve known of the dangers of mold in food for thousands of years. History is filled with examples of mold ingestion harming human health, from the Irish potato famine to the use of mold-toxins in modern bio-weapons. We know the inhalation of mold is one of the leading causes of asthma and sinusitis and can cause life-threatening pneumonia (hypersensitivity pneumonitis). Medical doctors are now receiving specialized training so they can start to deal with the increasing number of patients with mold-related illness. Researchers are discovering new mold toxins (mycotoxins) every month which when present can be the most powerful carcinogens on the planet.
There really is no controversy as to whether there is a health impact – only how much of an impact for who and the degree of the impact. Realize that there are hundreds of thousands of species of molds. These molds release spores, chemicals (called microbial VOCs) and mycotoxins differently depending on the materials they are consuming, the weather conditions, the degree of water involvement and the other species of mold in the vicinity.
The ‘Hype and Hysteria’ campaign marketers have little to worry about because industry and government have definitely shown their colors over the last decade. Any homeowner or renter?s policy now has clear mold-disclaimers and the responsibility has been given to the consumer to learn all about mold (mycology). Regulations have failed to help the citizenry despite massive popular support (example: The California Toxic Mold Protection Act).
And like the decades-long battle against the tobacco industry, which claimed smoking was not harmful to human health; this is going to take forever. Should there be regulations? Definitely. Will there be soon? No way. As previously stated, there is too much to lose and this country would go bankrupt within six months because the truth would unlock too many mysteries and liability.
But landlords, builders, insurance and home-sellers beware. Mold lawsuits may have been dampened by disclaimers and lies. But because the problem is growing (literally) and millions are being impacted across America, the lawsuits continue. Personal and property damage is in the billions of dollars and climbing. So, educating ourselves about how to avoid the problem and taking a grassroots effort in solving the problem correctly is imperative to avoid very expensive litigation for mom and pop, builders, insurers or landlords.
This isn’t really a ‘hype’ or ‘hysteria’ at all. But, anytime you have victims being told by the ignorant (or greedy) that their loss is imagined, you are going to have fireworks. That is why there has been so much propaganda regarding ‘hype’, ‘mild, allergic reactions in immune-compromised individuals’, and ‘hysteria’. Don’t believe a word of it for a minute. There are hundreds of scientific papers on this very sire documenting the very effects on healthy people that household mold can destroy healthy people?s lives.
Next time you read a story about ‘hype’ and ‘hysteria’ in a mold story, question who is behind the real message, because now you know the truth. The chances are that the story is about one of the major industries listed above.
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