—— Question 2: Is MOLD a CONTAMINANT? ——
Let's start by defining CONTAMINANT.
A contaminant is any biological, chemical, physical, or radiological substance (normally absent in the environment) which, in sufficient concentration, can adversely affect living organisms through air, water, soil, and/or food.
While MOLD is ubiquitous to the environment (meaning that it is found EVERYWHERE), mold definitely fits this definition and therefore the short answer is YES — Mold IS a contaminant!
According to the EPA, “All molds have the potential to cause [negative] health effects. Molds produce allergens, irritants, and in some cases, toxins that may cause reactions in humans. The types and severity of symptoms depend, in part, on the types of mold present, the extent of an individual's exposure, the ages of the individuals, and their existing sensitivities or allergies.”
How contamination occurs, which types of molds are considered dangerous contaminants, and what exactly are the adverse effects they have on humans, requires a more in depth answer.
Now let's define MOLD.
Molds (and mildew) are a subset of organisms called fungi. Fungi have been given their own kingdom (a taxonomic rank that is composed of smaller groups like genus and species) because they are neither plants nor animals.
All fungi have three distinct characteristics:
1.) A rigid outer cell wall;
2.) A complete lack of chlorophyll, which means they cannot use photosynthesis to produce their
own food (like plants do);
3.) They reproduce by creating very tiny, microscopic replicas of themselves called spores.
Mold fungi are defined as microscopic organisms that form filaments (thin threads or rods) and generally appear as a circular colony. Some molds have a "fluffy" appearance (like cotton or wool), while others can appear smooth. Molds are considered a subset of fungi because their filaments (thread-like, elongated thin series of cells attached one to another, or a very long thin cylindrical single cell) are not organized into large fruiting bodies, like those of mushrooms.
Mold can grow by extension of hyphae that are like tiny root hairs. In this way, a small colony of mold can expand to cover many square feet of material. Mold also reproduces by creating spores (tiny, microscopic replicas of themselves) that are similar to very small seeds. When spores are released they can be carried by air (airborne) or water to new locations. Some spores are so small that they are more affected by air currents than by gravity.
In molds, these miniature spores look just like the parent mold (some may call it plant-like), but remain dormant (like a seed) until the proper growing environment is presented. This is not difficult to achieve. It only takes oxygen, moisture, a food source (any organic material will do), and the right temperature. When that happens, the mold will begin its primary metabolic processes (those processes directly involved in normal growth, development, and reproduction) and multiply quickly into a visible mold colony.
No one knows exactly how many species of molds exist. So far, around 100,000 species have been identified, and it is estimated that there could be around 400,000. The general purpose of mold fungi is to feed on dead or decaying organic matter. This is simply nature’s way of recycling dead plant and animal life in the outside environment. However, this is certainly NOT what you want happening in your home or work environment, so . . .
Let's separate the potentially harmful molds from the rest.
For this purpose, molds can be divided into two main groups: Those molds that are unlikely to have a negative effect on humans, and those molds that potentially could cause harm. The later group is further divided into three distinct types of potentially harmful molds: Allergenic, Pathogenic, and Toxigenic. It is important to note that these are not strict distinctions, and that certain molds can be described as all three: allergenic, pathogenic, and toxigenic. Some molds are further described as irritants if they are likely to cause inflammation of the tissue. Since inflammation is the body’s natural response to foreign substances, especially infections, irritants are not considered a separate mold grouping. Mold species that cause inflammation can be found in allergenic, pathogenic, and toxigenic groups.
Harmless molds are those molds that are unlikely to have any negative effect on human health or cause structural damage to building materials. One specific group of harmless molds that are found in construction timbers is known as Sap-Stain Wood Fungi (also called blue-stain molds and cosmetic molds). Wood timbers used in construction are primarily cut from the sapwood of trees. The sapwood is where all the water, minerals, hormones and nutrients are found as a sap. Sap-Stain fungi (primarily from Ascomycete and Dematiaceous molds), can infect the cut sapwood timbers that end up as part of the attic or wall framing in homes. Sap-Stain wood fungi are very noticeable because they literally discolor portions of the wood bluish, grayish, or black colors as they colonize. Sap-Stain is often misidentified as “toxic black mold.” A thorough and professional inspection can determine if there are any harmful molds (or other microbials) coexisting with the Sap-Stain wood fungi, or if you just have permanently stained wood and no cause for concern.
Many molds have the potential to cause an allergic reaction in individuals who are exposed to a high enough concentration of mold spores. This is not uncommon, and many individuals are allergic to things like pollens, dust mites, pet dander, particulates, plants, certain foods, and chemicals. Allergic reactions happen when the immune system recognizes a substance as foreign and then goes on the attack to remove it from the body. The more sensitive an individual is to the foreign substance, the more severe the reaction can become. Most allergic reactions to molds are minor; however, some can become life-threatening.
Breathing in mold spores is the most common cause of respiratory mold allergies in humans. Individuals may also experience allergic reactions when foods containing mold are ingested, as well as from direct contact with certain molds that produce rashes on the skin. With indoor environments, we are primarily concerned with the inhalation of airborne spores, and the effects these spores can have on the health of individuals living in buildings where mold is active.
Molds produce spores as part of their reproductive process. They do this by the spontaneous division of a single cell into four or more daughter cells, each of which contains a part of the original nucleus. These spores quickly become airborne. Since mold spores are smaller and lighter than pollen, they have the ability to move through the nasal passages and even into the lungs without any problem. They can bypass the body’s defenses and become lodged anywhere along the respiratory system, including the lungs.
Many individuals can suffer with seasonal allergy symptoms from inhalation of massive amounts of mold spores even though they do not have a particular mold sensitivity. This is because the body can become overwhelmed. These individuals are fine once they stop breathing air saturated with mold spores. Of course, this is problematic if the indoor environment is saturated with spores due to active mold in the indoor environment!
Some individuals are sensitive to the chemicals found in, and produced by specific molds. Allergy tests can be preformed to determine the level of sensitivity and species of molds that the individual is allergic to. Some medical treatments are available to help desensitize these individuals. However, if the indoor environment is continually being polluted from active mold, then it is unlikely any treatments will have an opportunity to be effective.
Then there are those individuals who already have respiratory problems or compromised immune systems (such as AIDS or cancer patients). For these individuals, any reaction can become life-threatening. Even limited exposure to certain molds could cause death.
Allergenic molds are known to cause the following conditions in some individuals:
• Allergic Rhinitis: This is a collection of symptoms that is generally triggered when breathing in a foreign substance one is sensitive to. Symptoms can include sneezing, coughing, runny nose, sore throat, stuffiness, swelling, headache, dizziness, fever, chills, sweats, and other flu-like symptoms. These can range in severity depending on the general health of the individual, the amount of the allergenic substance inhaled, and the level of individual sensitivity. It is estimated that this affects around 30% of the population.
• Asthma: This is a more serious allergic response that results from hypersensitivity to a foreign substance in the respiratory system. It causes spasms in the bronchi of the lungs, making it difficult to breathe and, in some cases can become life-threatening. Several indoor molds (Cladosporium sp., Alternaria sp., Penicillium sp., and Aspergillus sp.) are know to trigger an asthma attack, and individuals with this condition need to be very careful especially when around damp indoor environments. It is estimated that around 5% of the population have this condition.
• Hypersensitivity Pneumonitis: (Also know as Extrinsic Allergic Alveolitis.) This is inflammation of the lungs due to breathing in a foreign substance, mostly certain types of dust, fungus, or molds. Reactions tend to be more severe with continued exposure leading to chronic lung disease. Common names for this condition include: Farmers lung, Mushroom pickers disease, Humidifier or air-conditioner lung, and Bird Breeders or bird fanciers lung. Symptoms include: Chills, coughs, fever, general illness, shortness of breath, loss of appetite, and unintentional weight loss. Homeowners with HVAC systems need to be aware of this condition and have their systems cleaned and maintained on a regular basis.
• Allergic Bronchopulmonary Aspergillosis (ABPA): This is an inflammatory condition of the respiratory airways caused by a hypersensitivity (extreme allergic response) of the immune system to the Aspergillus species of molds (most notably Aspergillus Fumigatus). Aspergillus is commonly found in both the outdoor and indoor environment. These spores are so common that even healthy individuals have some of these spores in the mucus produced in their lower airways. Normally these spores are not problematic. However, some species of Aspergillus are considered opportunistic (taking advantage of an individual’s weakened state). Allergic Bronchopulmonary Aspergillosis is most likely to occur when Aspergillus mold spores are introduced in sufficient amounts to individuals who are hypersensitive or already have respiratory conditions such as asthma or cystic fibrosis. While this is considered a serious medical issue, this type of Aspergillosis is treatable when diagnosed in a timely manner.
While there is little anyone can (or should) do about mold spores in the outside environment, molds that have become active in the indoor environment can severely compromise the indoor air quality, causing harm to specific individuals. Individuals with mold allergies are encouraged to keep their indoor environments free and clear of mold activity. Molds found in abundance (and therefore most likely to cause seasonal allergic reactions) include: Alternaria, Cladosporium, Aspergillus, Penicillium, Helminthosporium, Epicoccum, Fusarium, Mucor, Rhizopus, and Aureobasidium.
Pathogenic molds are those species that are capable of causing infections in humans. Infection occurs from the invasion and multiplication of microorganisms in body tissues, causing cellular injury to the individual. Pathogenic molds can infect healthy individuals as well as those individuals who have mold sensitivities and respiratory illnesses. An allergic reaction can turn into an infection if the microorganism (mold in this case) is both capable and able to penetrate the body’s tissues. A sinus infection is a good example of this.
Mold infections (also called mycoses) are classified depending on the degree of tissue involvement and the tissue levels initially colonized. Infections can occur from direct contact, ingestion, or inhalation of mold and spores. There are four main classifications:
I. Superficial: Those infections that are limited to the outermost layers of the skin, hair, and nails, and do not produce an immune response. A few examples of this include:
• Piedra is an infection of the hair shaft. Black piedra is caused by Piedraia hortae mold, and white piedra is caused by Trichosporon mold species.
• Tinea nigra is an infection on the hands and soles, causing brown or black, superficial skin lesions. Tinea nigra is caused by the Hortaea werneckii mold species.
• Otitis externa is an infection of the external ear, caused by Aspergillus, Malassezia sp. or Pseudalleschieria boydii species of molds.
• Superficial dermatophytosis is an infection of the hair, nail or skin infection caused by Keratinophilic dermatophytous molds Arthroconidia and Trichophyton.
II. Subcutaneous: Those infections that extend deeper into the epidermis, subcutaneous tissue or adjacent structures. A few examples include:
• Ringworm is an infection in the skin, with circular skin lesions with slightly raised, red margins containing numerous scales and surrounded by reddish, itching skin. It is not caused by worms, but rather by various types of molds including Mycosporum, Trichophyton and Epidermaphyton.
• Favus is a skin infection with bald patches on the haired skin caused by Trichophyton schoenleinii mold.
• Hyperkeratosis is a skin infection with extended hand and foot scaling caused by Nattrassia mangiferae mold.
• Intertrigo is the yeast Candida infection of humid folds of the skin.
III. Systemic: Those infections that penetrate deep into internal organs. A few examples include:
• Eumycetoma is an infection in which necrotic, pus-oozing lesion cavities are formed in tissue. Eumycetoma is caused by a variety of molds including Acremonium, Neotestudina, Pseudallescheria, Madurella, Leptosphaeria Pyrenochaeta and black yeast Exophiala.
• Subcutaneous conidiobolomycosis is a skin infection of the legs, arms and buttocks, caused by Conidiobolus and Basidiobolus molds.
• Zygomycotic rhinitis is an infection of the mucous membranes by Zygomycetes molds (particulary the Rhizopus genus) and can lead to meningitis.
• Mycotic sinusitis is an acute infection of the nasal mucous membranes with allergic reactions to local colonization, mostly caused by Mucorales or Aspergillus, as well as some nonpathogenic molds such as Curvularia, Bipolaris and Exserohilum. In immunocompromised patients, this infection can be fatal.
IV. Opportunistic: Also known as Opportunistic Invasive Fungal Infections are a major cause of disease and death in immunocompromised individuals (patients with AIDS, cancer, or congenital disorders). A few examples include:
• Blastomycosis is a serious lung infection, caused by Blastomyces dermatitidis mold. If untreated, the disease can spread throughout the body and is usually fatal.
• Coccidioidomycosis is a serious lung infection contracted through inhalation of airborne spores of Coccidioides immitis mold. Symptoms include non-specific fever with bronchopneumonia. In rare cases, the infection can spread throughout the whole body, which is often fatal.
• Penicilliosis is an infection caused by inhaling Penicillium marneffei mold. Without healthy white blood cells to fight off this infection, it can multiply quickly and spread throughout the body. It is often fatal if left untreated.
• Aspergillosis (including Aspergilloma and Invasive Aspergillosis) is mostly caused by Aspergillus Flavus or Aspergillus Fumigatus molds.
Aspergillosis is inflammation of the respiratory airways that can turn into a serious fungal infection. Aspergillosis is primarily caused by breathing in aspergillus mold spores. Infection can occur in the ear canal, eyes, nose, sinus cavities, and lungs. In some individuals, the infection can even invade bone and the membranes that enclose the brain and spinal cord, leading to meningitis. Individuals who are sensitive to the Aspergillus species of molds and who have compromised immune systems, or a history or respiratory problems, or who are weakened due to recent surgery or illnesses, are at risk of developing Aspergillosis.
Aspergilloma refers to the mass formed when fungal spores settle into or colonize areas of the lung that have been pitted and scarred as a result of tuberculosis or prior pneumonia. Invasive Aspergillosis infection refers to rare cases in which the fungus spreads throughout the body via the blood stream and invades other organ systems. Once established, invasive fungal infections are extremely difficult to cure and the death rate is extremely high.
• Cryptococcosis is a fatal fungal infection that often leads to meningitis. It is caused by Cryptococcus neoformans yeast.
• Candidiasis is an infection caused by Candida Albicans, Candida Tropicalis, or Candida Glabrata. The species is commonly present in human mucus, which becomes invasive when immunity weakens. Newborns and the elderly are also at risk due to their naturally low resistance. Candidiasis can develop within a few days. Disseminated Cadidiasis can be fatal if left untreated.
• Zygomycosis is an slow invasive infection of the blood vessels, caused by Mucorales and Rhizopus (saprobic zygomycetes) mold species.
Certain molds, such as Aspergillus, Fusarium, Penicillium, Chaetomium and Stachybotrys release chemicals during their metabolic cycle called mycotoxins, which are considered to be toxic in humans and animals. Mycotoxins are produced as secondary metabolites and are not considered mandatory for survival of mold species. These mycotoxins (chemicals) can be found in the mold spores, within the mold itself, and in the materials where the mold is growing. Inhalation of mold spores or dust containing mycotoxins can result in human exposure with potentially severe health effects.
Mold itself is not toxic. It is only the mycotoxins which some molds produce that are toxic. Mycotoxins are more likely to trigger health problems in even healthy individuals because they are considered poisonous. These toxins are believed to be linked to memory loss, severe lung problems, cancer, and renal shut-down. Even high cholesterol is now thought to be connected to prolonged exposure to mycotoxins.
Not all molds produce mycotoxins, and the purpose of mycotoxins is not always clear. Their production may be in response to threat or stress. This may mean that more mycotoxins are released into the indoor air environment when homeowners try to clean, kill, or remove the mold colony. Any mold that produces mycotoxins can be harmful (even deadly) to human health and therefore should only be removed by licensed professionals. The spreading of toxic spores can lead to greater contamination throughout the home or indoor work environment. ALL MYCOTOXIN-PRODUCING MOLDS MUST BE PROFESSIONALLY AND COMPLETELY REMOVED FROM ALL INDOOR ENVIRONMENTS!
The World Health Organization (WHO) publication on mycotoxins said that there are more than 200 mycotoxins produced by a variety of common fungi. Some include sterigmatocystin produced by Aspergillus versicolor; aflatoxins produced by Aspergillus flavus; fumonisins produced by Fusarium spp.; ochratoxins produced by Aspergillus ochraceus; and trichothecenes such as satratoxins produced by Stachybotrys chartarum.
Specific mycotoxins and the molds that produce them, found in indoor environments:
• The most commonly discussed of these molds is Stachybotrys Chartarum, (also known as Toxic Black Mold). It is a slimy, greenish-black mold that easily grows on damp building materials containing cellulose (such as wood, paper, and drywall). It does not grow on tile or cement. It is often found throughout the indoor environment where moisture is (or has been) a problem including bathrooms, basements, and attics. Stachybotrys chartarum produces trichothecenes, a group of highly potent mycotoxins linked to biological warfare agents better known as yellow rain.
Not all mycotoxins are trichothecenes, but all trichothecenes are mycotoxins. The main atrichothecene produced by Stachybotrys Chartarum in called Satratoxin. The clinical condition it causes is known as Stachybotryotoxicosis. Basic symptoms include burning and blistering of mouth and nose, a rash that becomes a moist dermatitis, nosebleeds, chest pain, pulmonary hemorrhage, hyperthermia (raised temperature), headache, fatigue, and diarrhea. Prolonged exposure can lead to death. Individuals with weekend immune systems due to illness or age (elderly and children), are at the greatest risk of death from this type of poisoning.
• Aspergillus Flavus and Aspergillus Parasiticus contain a carcinogenic mycotoxin called Aflatoxin B1, that contributes to the growth of liver and kidney cancer. There is no specific antidote for aflatoxicosis. When young, aspergillus flavus appear yellow green in color. As the fungus ages, the spores turn a darker green. In buildings and the home, Aspergillus often can be found growing inside dirty air conditioners. This has even been a problem in some hospitals. Aspergillus also grows well on building materials and so it might often grow on or inside walls in the home, particularly if the house is damp or has been damaged by flooding.
• Fusaruim spp. produces a mycotoxin called Fumonisins. Fumonisin poisoning is well-known in animals and is generally introduced in grain feed, particularly that of corn. It is dangerous to humans when ingested or inhaled in significant quantities. Fumonisins attack the circulatory system, cause vomiting and hemorrhaging. The mold can be found in wet place within the home environment such as sink drains, humidifiers, and HVAC systems. The dry spores can also be found on carpets and in dust.
• Aspergillus Versicolor produces a mycotoxin called Sterigmatocystin. Sterigmatocystin is a poison structurally related to Aflatoxin B1, and is a potent liver and kidney carcinogen similar to Aflatoxin B1. Sterigmatocystin is frequently found in water-damaged buildings and is harmful to humans when ingested or inhaled in significant quantities. Testing of buildings damaged by hurricane Katrina showed extremely high levels of sterigmatocytin in the dust. Aspergillus Versicolor is generally bright green in color but may also appear with bluish, reddish-brown, or brown areas of growth. It will grow on just about any medium.
• Aspergillus Ochraceus produces a mycotoxin called Ochratoxins (primarily Ochratoxin A, also known as OTA) that is known to be a toxic carcinogenic found in certain foods such as coffee beans and dried fruit, and in dust from indoor environments. OTA infects the liver, kidney, and lungs of both humans and animals. Infection commonly occurs from ingestion of foods contaminated with OTA, but recent evidence now confirms that inhalation of dust that contains this mycotoxin (such as in carpets and HVAC ducts), is becoming more prevalent and therefore of greater concern for the indoor air quality industry. Renal failure is typical from this type of poisoning. Aspergillus Ochraceus is typically yellowish-brown in color.
Steve Timpany, President of SMS Indoor Environment Cleaning, Inc., is an ACAC Council-certified Residential Mold Inspector (CRMI), and can help you determine if the mold in your home or business environment is a contaminant that needs to be professionally removed.
SMS Indoor Environmental Cleaning, Inc., is a Mold Remediation Company that specializes in the Identification and Elimination of Microbial Contamination. Our Indoor Environmental Cleaning Services include: Mold Remediation, Water & Flood Damage Restoration, Air Duct & HVAC Systems, Dryer Vents, Industrial Facilities & Manufacturing Equipment, and Home Decontamination & Clean-Down. To learn more about how we can help you solve your mold problems, call Steve Timpany at 800-845-3022 or email at steve@SMSindoor.com.
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