More on Allergenic Molds
Along with pollens from trees, grasses, and weeds, molds are an important cause of seasonal allergic rhinitis. People allergic to molds may have symptoms from spring to late fall. The mold season often peaks from July to late summer. Unlike pollens, molds may persist after the first killing frost. Some can grow at subfreezing temperatures, but most become dormant. Snow cover lowers the outdoor mold count dramatically but does not kill molds. After the spring thaw, molds thrive on the vegetation that has been killed by the winter cold.

In the warmest areas of the United States, however, molds thrive all year and can cause year-round (perennial) allergic problems. In addition, molds growing indoors can cause perennial allergic rhinitis even in the coldest climates.

When inhaled, microscopic fungal spores, or sometimes fragments of fungi may cause allergic rhinitis. Because they are so small, mold spores may evade the protective mechanisms of the nose and upper respiratory tract to reach the lungs.

In a small number of people, symptoms of mold allergy may be brought on or worsened by eating certain foods, such as cheeses processed with fungi. Occasionally, mushrooms, dried fruits, and foods containing yeast, soy sauce, or vinegar will produce allergic symptoms. There is no known relationship, however, between a respiratory allergy to the mold Penicillium and an allergy to the drug penicillin, made from the mold.

Which molds are allergenic?
Like pollens, mold spores are important airborne allergens only if they are abundant, easily carried by air currents, and allergenic in their chemical makeup. Found almost everywhere, mold spores in some areas are so numerous they often outnumber the pollens in the air. Fortunately, however, only a few dozen different types are significant allergens.

In general, Alternaria and Cladosporium (Hormodendrum) are the molds most commonly found both indoors and outdoors throughout the United States. Aspergillus, Penicillium, Helminthosporium, Epicoccum, Fusarium, Mucor, Rhizopus, and Aureobasidium (Pullularia) are also common.

Mold counts
Similar to pollen counts, mold counts may suggest the types and relative quantities of fungi present at a certain time and place. For several reasons, however, these counts probably cannot be used as a constant guide for daily activities. One reason is that the number and types of spores actually present in the mold count may have changed considerably in 24 hours because weather and spore dispersal are directly related. Many of the common allergenic molds are of the dry spore type--they release their spores during dry, windy weather. Other fungi need high humidity, fog, or dew to release their spores. Although rain washes many larger spores out of the air, it also causes some smaller spores to be shot into the air.

In addition to the effect of day-to-day weather changes on mold counts, spore populations may also differ between day and night. Day favors dispersal by dry spore types and night favors wet spore types.

Other mold-related disorders
Fungi or microorganisms related to them may cause other health problems similar to allergic diseases. Some kinds of Aspergillus may cause several different illnesses, including both infections and allergy. These fungi may lodge in the airways or a distant part of the lung and grow until they form a compact sphere known as a "fungus ball." In people with lung damage or serious underlying illnesses, Aspergillus may grasp the opportunity to invade the lungs or the whole body.

In some individuals, exposure to these fungi also can lead to asthma or to a lung disease resembling severe inflammatory asthma called allergic bronchopulmonary aspergillosis. This latter condition, which occurs only in a minority of people with asthma, is characterized by wheezing, low-grade fever, and coughing up of brown-flecked masses or mucus plugs. Skin testing, blood tests, X-rays, and examination of the sputum for fungi can help establish the diagnosis. Corticosteroid drugs are usually effective in treating this reaction; immunotherapy (allergy shots) is not helpful.

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More On Pathogenic Molds
Pathogenic molds usually produce some type of infection. The word pathogenic literally means, "capable of causing disease". A normal, healthy individual can probably resist infection by these organisms regardless of dose, however, pathogenic molds can cause serious health effects in persons with suppressed, underdeveloped, or compromised immune systems. In some cases, high exposure may cause hypersensitivity pneumonitis (an acute response to exposure to an organism). People with compromised immune systems would be, infants and small children whose immune systems are not fully developed, elderly people whose immune systems are essentially worn out, and anyone exposed to AIDS, chemotherapy, pneumonia, bronchitis, and other respiratory infections.

Bipolaris Species
The U.S. Government's Occupational Safety and Health Administration [OSHA] lists the following as the health effects of Bipolaris mold: Allergen, Irritant, Hypersensitivity pneumonitis, Dermatitis.

Bipolaris australiensis showing sympodial development of pale brown, fusiform to ellipsoidal, pseudoseptate, poroconidia on a geniculate or zig-zag rachis.

Colonies are moderately fast growing, effuse, grey to blackish brown, suede-like to floccose with a black reverse. Microscopic morphology shows sympodial development of pale brown pigmented, pseudoseptate conidia on a geniculate or zig-zag rachis. Conidia are produced through pores in the conidiophore wall (poroconidia) and are straight, fusiform to ellipsoidal, rounded at both ends, smooth to finely roughened and germinating only from the ends (bipolar).

Description and Natural Habitats
Bipolaris is a dematiaceous, filamentous fungus. It is cosmopolitan in nature and is isolated from plant debris and soil. The pathogenic species have known teleomorphic states in the genus Cochliobolus and produce ascospores.

Species
The genus Bipolaris contains several species. Among these, three well-known pathogenic species are Bipolaris spicifera, Bipolaris australiensis, and Bipolaris hawaiiensis. The genus Bipolaris contains about 45 species which are mostly subtropical and tropical plant parasites. However, several species notably B. australiensis, B. hawaiiensis and B. spicifera, are well documented human pathogens. Clinical manifestations include mycotic keratitis, subcutaneous phaeohyphomycosis, sinusitis, peritonitis in patients on continuous ambulatory peritoneal dialysis (CAPD), and cerebral and disseminated infections.

Pathogenicity and Clinical Significance
Bipolaris is one of the causative agents of phaeohyphomycosis. The clinical spectrum is diverse, including allergic and chronic invasive sinusitis, keratitis, endophthalmitis, endocarditis, endarteritis, osteomyelitis, meningoencephalitis, peritonitis, otitis media (in agricultural field workers),and fungemia as well as cutaneous and pulmonary infections and allergic bronchopulmonary disease. Bipolaris can infect both immunocompetent and immunocompromised host.

As well as being isolated as saprophytes on plants, Bipolaris may be pathogenic to certain plant species, particularly to Graminiae and also to animals, such as the dog. It may cause nasal mycotic granuloma in the cattle. Bipolaris may also be isolated as a laboratory contaminant.

Macroscopic Features
Bipolaris colonies grow rapidly, reaching a diameter of 3 to 9 cm following incubation at 25°C for 7 days on potato dextrose agar. The colony becomes mature within 5 days. The texture is velvety to woolly. The surface of the colony is initially white to grayish brown and becomes olive green to black with a raised grayish periphery as it matures. The reverse is also darkly pigmented and olive to black in color. The hyphae are septate and brown. Conidiophores (4.5-6 µm wide) are brown, simple or branched, geniculate and sympodial, bending at the points where each conidium arises from. This property leads to the zigzag appearance of the conidiophore. The conidia, which are also called poroconidia, are 3- to 6-celled, fusoid to cylindrical in shape, light to dark brown in color and have sympodial geniculate growth pattern. The poroconidium (30-35 µm x 11-13.5 µm) is distoseptate and has a scarcely protuberant, darkly pigmented hilum. This basal scar indicates the point of attachment to the conidiophore. From the terminal cell of the conidium, germ tubes may develop and elongate in the direction of longitudinal axis of the conidium.

Teleomorph production of Bipolaris is heterothallic. The perithecium is black in color, and round to ellipsoidal in shape. The ascospores are flagelliform or filiform, hyaline in nature and are found in clavate-shaped or cylindrical asci. Each ascus contains eight ascospores.

Laboratory Precautions
No special precautions other than general laboratory precautions are required.

Susceptibility
In vitro susceptibility testing procedures have not been standardized for dematiaceous fungi yet. Very limited data are available on susceptibility of Bipolaris. These data suggest that itraconazole MICs are variable and voriconazole MICs are considerably low.

Amphotericin B and ketoconazole are used in treatment of Bipolaris infections. Surgical debridement may be indicated in some cases, such as sinusitis.

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More On Toxic Molds
"Black Mold" is a term commonly used to describe molds that are black and slimy. It is also often used in reference to toxic mold; molds that are know to present health risks to humans and animals by producing Mycotoxins (poisons). Mycotoxins are fungal metabolites that have been identified as toxic agents.

It should be noted, however, that not all black mold is toxic and that not all toxic mold is black. In fact, there are over 400,000 different types of mold and many of them are black in color of which only a portion have been identified. Black mold and/or toxic mold are terms often used in reference to Stachybotrys, (stack-ee-bot-ris) aka: Stachybotrys chartarum, aka: Stachybotrys atra.

Many fungi (e.g., species of Aspergillus, Penicillium, Fusarium, Trichoderma, and Memnoniella) in addition to Stachybotrys can produce potent mycotoxins, some of which are identical to compounds produced by Stachybotrys. For this reason, Stachybotrys cannot be treated as uniquely toxic in indoor environments.

OVERVIEW:
Virtually everyone has some type of mold or another somewhere in their home. Although not all types are toxic, it is sometimes difficult to distinguish types without lab testing. Black molds can develop from water seepage, and while toxic mold is less common than other mold species, it is not rare. For that reason, it is imperative to treat and remove all molds as if they are potentially harmful. Regardless of the type of mold found, a home containing mold is not essentially a healthy home.

The notoriety of Stachybotrys leads some to believe that is the only “toxic mold”. That is not true. A number of toxigenic molds have been found during indoor air quality investigations in different parts of the world. Among the genera most frequently found in numbers exceeding levels that they reach outdoors are Aspergillus, Penicillium, Stachybotrys, and Cladosporium (Burge, 1986; Smith et al., 1992; Hirsh and Sosman, 1976; Verhoeff et al., 1992; Miller et al., 1988; Gravesen et al., 1999). Penicillium, Aspergillus and Stachybotrys toxicity, especially as it relates to indoor exposures, are discussed briefly in the paragraphs that follow.

PENICILLIUM:
Penicillium species have been shown to be fairly common indoors, even in clean environments, but can be problematic when indoor spore levels are higher than outdoors (Burge, 1986; Miller et al., 1988; Flannigan and Miller, 1994). Spores have the highest concentrations of mycotoxins, although the vegetative portion of the mold, the mycelium, can also contain the poison. The viability of spores is not essential to toxicity. In other words, a dead spore can still be a source of toxin.

ASPERGILLUS:
Aspergillus species are also fairly prevalent in problem buildings. This genus contains several toxigenic species, among which the most important are, A. parasiticus, A. flavus, and A. fumigatus. Aflatoxins produced by the first two species are among the most extensively studied mycotoxins. They are among the most toxic substances known, being acutely toxic to the liver, brain, kidneys and heart, and with chronic exposure, potent carcinogens of the liver. They are also teratogenic (Smith and Moss, 1985; Burge, 1986). Symptoms of acute aflatoxicosis are fever, vomiting, coma and convulsions (Smith and Moss, 1985). A. flavus is found indoors in tropical and subtropical regions, and occasionally in specific environments such as flowerpots. A. fumigatus has been found in many indoor samples. A more common aspergillus species found in wet buildings is A. versicolor, where it has been found growing on wallpaper, wooden floors, fibreboard and other building material. A. versicolor does not produce aflatoxins, but does produce a less potent toxin, sterigmatocystin, an aflatoxin precursor (Gravesen et al., 1994). While symptoms of aflatoxin exposure through ingestion are well described, symptoms of exposure such as might occur in most moderately contaminated buildings are not know, but are undoubtedly less severe due to reduced exposure. However, the potent toxicity of these agents advise that prudent prevention of exposures are warranted when levels of aspergilli indoors exceed outdoor levels by any significant amount. A. fumigatus has been found in many indoor samples. This mold is more often associated with the infectious disease aspergillosis, but this species does produce poisons for which only crude toxicity tests have been done (Betina, 1989). Recent work has found a number of tremorgenic toxins in the conidia of this species (Land et al., 1994). A. ochraceus produces ochratoxins (also produced by some penicillia as mentioned above). Ochratoxins damage the kidney and are carcinogenic (Smith and Moss, 1985).

STACHYBOTRYS:
Stachybotrys chartarum (atra) has been much discussed in the popular press and has been the subject of a number of building related illness investigations. It is a mold that is not readily measured from air samples because its spores, when wet, are sticky and not easily aerosolized. Because it does not compete well with other molds or bacteria, it is easily overgrown in a sample, especially since it does not grow well on standard media (Jarvis, 1990). Its inability to compete may also result in its being killed off by other organisms in the sample mixture. Thus, even if it is physically captured, it will not be viable and will not be identified in a cultured sample media, even though it is present in the environment and those who breathe it can have toxic exposures. For that reason, it is prudent to take a surface sample, such as tape or bulk, whenever evidence of black mold is found. This organism has a high moisture requirement, so it grows vigorously where moisture has accumulated from roof or wall leaks, or chronically wet areas from plumbing leaks. It is often hidden within the building envelope and inside wall cavities. When Stachybotrys is found in an air sample, it should be searched out in walls or other hidden spaces, where it is likely to be growing in abundance. This mold has a very low nitrogen requirement, and can grow on wet hay and straw, paper, wallpaper, ceiling tiles, carpets, insulation material (especially cellulose-based insulation).

This information was quoted from an article called “Is Indoor Mold Contamination a Threat to Health?” by Harriet M. Ammann, Ph.D., D.A.B.T. - Senior Toxicologist at Washington State Department of Health, Olympia, Washington.
For a full copy of her report in PDF format CLICK HERE
For a full copy of her report in Microsoft Word format CLICK HERE

Stachybotrys is a specific family (genus) of mold that is present in the environment. Out-of-doors stachybotrys molds help to decay organic matter. One particular species known as stachybotrys atra (sometimes known as stachybotrys chartarum) is prone to growth indoors. This mold is normally dark brown or black in color. It can look slimy, sooty, or even like grayish white strands depending on the amount of moisture available and the length of time it has been growing. It is important to remember that many other common indoor molds can look similar to stachybotrys (including cladosporium, aspergillus, alternaria, and drechslera), so testing is critical to conclusively identify stachybotrys in a building. Stachybotrys mold needs the proper conditions in order to grow, including moisture, a nutrient source, temperature, and time. Standing water or a relative humidity of 90% or higher is necessary for stachybotrys to start germination and grow. However, once the stachybotrys begins to grow it can continue to propagate even if the surface water source dries up and the relative humidity falls to 70%. The nutrient sources that best support stachybotrys are those with a high cellulose content. As such, stachybotrys thrives on natural materials such as hay, straw, and wood chips, as well as building materials such as ceiling tile, drywall, paper vapor barriers, wallpaper, insulation backing, cardboard boxes, and paper files. Stachybotrys survives a wide variation in temperature and grows most proficiently in temperatures that humans consider warm to moderately hot. It tends to develop more slowly than many other molds—one to two weeks after moisture intrusion as compared to one to two days for molds like aspergillus, penicillium, or cladosporium. Despite its slow start, stachybotrys usually develops into the dominant mold if the conditions are favorable, eventually crowding out other mold types that may have colonized the material first.

Like many other molds, stachybotrys can spread both through the generation of spores and the growth of root-like structures called mycelia. Stachybotrys spores grow in clusters at the end of stem-like structures known as hyphae. The spores do not easily disperse into the air if the colonized material is wet, as the spores are held together by a sticky/slimy coating. Distribution through the air is possible when the mold dries out or is disturbed. Because of this danger of the airborne dispersion of spores, all cleaning and removal of stachybotrys mold should be done using appropriate controls.

Stachybotrys has a high moisture requirement, so it grows vigorously where moisture has accumulated from roof or wall leaks, or chronically wet areas from plumbing leaks. It is often hidden within the building envelope. When S. chartarum is found in an air sample, it should be searched out in walls or other hidden spaces, where it is likely to be growing in abundance. This mold has a very low nitrogen requirement, and can grow on wet hay and straw, paper, wallpaper, ceiling tiles, carpets, insulation material (especially cellulose-based insulation). It also grows well when wet filter paper is used as a capturing medium.

S. chartarum has a well-known history in Russia and the Ukraine, where it has killed thousands of horses, which seem to be especially susceptible to its toxins. These toxins are macrocyclic trichothecenes. They cause lesions of the skin and gastrointestinal tract, and interfere with blood cell formation. (Sorenson, 1993). Persons handling material heavily contaminated with this mold describe symptoms of cough, rhinitis, burning sensations of the mouth and nasal passages and cutaneous irritation at the point of contact, especially in areas of heavy perspiration, such as the armpits or the scrotum (Andrassy et al., 1979).

One case study of toxicosis associated with macrocyclic trichothecenes produced by S. chartarum in an indoor exposure, has been published (Croft et al., 1986), and has proven seminal in further investigations for toxic effects from molds found indoors. In this exposure of a family in a home with water damage from a leaky roof, complaints included (variably among family members and a maid) headaches, sore throats, hair loss, flu symptoms, diarrhea, fatigue, dermatitis, general malaise, psychological depression. (Croft et al, 1986; Jarvis, 1995).


SUMMARY:
Stachybotrys has a different make up than most other molds and does not produce airborne spore as easily as other molds. If you were to physically touch a spot of black mold, it would feel slimy and would smear on the area. Areas and substances where black mold can be found include water soaked wood, ceiling tiles, wall paneling, cardboard, even items made of cotton. Black mold can grow on drywall and insulation and can infest areas in the floors, walls and ceilings. Moisture is essential to the growth of black mold and, when it is wet, it is shiny in appearance.

If and when you are contemplating clean up of black mold, there are two important considerations:

1. Know what you are dealing with.
If you were told you have an animal in your house, your first question would be, “What kind of animal?” Based on the answer, you will know the best way to “suit up” for the encounter. If the intruder is a domestic house cat, you may need a pair of gloves to keep from getting scratched. If the intruder is a lion, you might want a whip, a chair, and a large caliber pistol just in case. The same is true with removing mold. Some jobs may require only an inexpensive dust mask and a pair of rubber gloves. Other jobs may require expensive, personal protection equipment, or possibly even a professional remediation contractor. Doing the job right the first time is the key to doing it once, or doing it over and over again.

2. Verify the extent of the problem.
Most indoor mold problems are the direct result of water intrusion, i.e. improper drainage and irrigation, plumbing leaks, rain and condensation issues. After determining the cause of a mold problem and correcting it, you will want to decide whether to do the clean up yourself or hire it out to a specialist. In the even you choose to do the clean up yourself, it is important to understand that bleach is only good for cleaning small amounts of mold off of a surfaces. It should not be used for cleaning mold that is deeply embedded into walls, floors and framing lumber. Bleach dries too quickly to penetrate deep enough into wood or drywall to reach embedded mold, therefore, it does not always reach mold that is embedded beyond the surface. Furthermore, bleach loses its bleachability quickly. Once it does, it simply adds more water to the equation, exacerbating the problem. For that reason, after or instead of cleaning with bleach, use a mildewcide (not a fungicide) disinfect cleaner to penetrate deep into contaminated construction materials to kill embedded mold. After this you must thoroughly dry the cleaned area. If there is any moisture remaining, it is only a matter of time before you will repeating the entire process. One way to be sure your clean up is effective is to have the cleaned materials re-tested by your inspector.

3. Hiring a Contractor
If you choose to have a contractor clean up the contamination, there are a couple of important matters for you to consider:

a) Only hire experienced IICRC Certified Mold Remediation Contractors, not a home remodeler. There are many fine and well established remodeling companies around who do great remodeling work but are not well experienced in mold remediation. Remodeling contractors who are not remediation specialist can make a bad situation worse because of their lack of mold experience.

b) Insist on references of customers who's jobs are at least one year old. A mold clean up job can look really great right after its finished. But if it isn't done correctly the problem can come back much worse than before within six months to a year.

c) Never allow your contractor to conduct his own post-remediation clearance testing. Always insist on an independent third party inspection company for post-remediation clearance testing.

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