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Exposure to Mold During Book Remediation By Dyron Hamlin

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Questions and Answers

I heard about toxic molds that grow in homes and other buildings. Should I be concerned about a serious health risk to me and my family?

The hazards presented by molds that may contain mycotoxins should be considered the same as other common molds which can grow in house. There is always a little mold everywhere – in the air on many surfaces. There are very few case reports that toxic (those containing certain mycotoxins) inside homes can cause or rare health conditions such as pulmonary hemorrhage or loss. These case reports are rare, and a causal link between presence of the toxic mold and these conditions has not been proven. A common-sense approach should be used for any mold existing inside buildings and homes. The common health from molds include hay fever-like allergic symptoms. Certain with chronic respiratory disease (chronic obstructive disorder, asthma) may experience difficulty breathing. with immune suppression may be at increased risk for infection molds. If you or your family members have these conditions, a medical clinician should be consulted for diagnosis and treatment For the most part, one should take routine measurres to prevent mold growth in the home.

How common is mold, including Stachybotrys chartarum (also known by its synonym Stachybotrys atra) in buildings?

Molds are very common in buildings and homes and will grow anywhere indoors where there is moisture. The most common indoor molds Cladosporium, Penicillium, Aspergillus, and Alternaria. We do have accurate information about how often Stachybotrys is found in buildings and homes. While it is less common than mold species, it is not rare.

How do molds get in the indoor environment and how do they grow?

Molds naturally grow in the indoor environment. Mold spores may also enter your house through open doorways, windows, heating, ventilation and air conditioning systems. Spores in the air outside also themselves to people and animals, making clothing, shoes, bags and pets convenient vehicles for carrying mold indoors.
When mold spores drop on places where there is excessive moisture, such as where leakage may have occurred in roofs, pipes, walls plant pots, or where there has been flooding, they will grow. building materials provide suitable nutrients that encourage to grow. Wet cellulose materials, including paper and paper products cardboard, ceiling tiles, wood, and wood products, are conducive for the growth of some molds. Other materials such dust, paints, wallpaper, insulation materials, drywall, carpet fabric, and upholstery, commonly support mold growth.

What is Stachybotrys chartarum (Stachybotrys atra)?

Stachybotrys chartarum (also known by its synonym Stachybotrys atra) is a greenish-black mold. It can grow on material with a cellulose and low nitrogen content, such as fiberboard, gypsum board paper, dust, and lint. Growth occurs when there is moisture water damage, excessive humidity, water leaks, condensation, infiltration, or flooding. Constant moisture is required for growth. It is not necessary, however, to determine what type mold you may have. All molds should be treated the same with to potential health risks and removal.

Are there any circumstances where people should vacate a home or other building because of mold?

These decisions have to be made individually. If you believe you are ill because of exposure to mold in a building, you should your physician to determine the appropriate action to take.

Who are the people who are most at risk for health problems associated with exposure to mold?

People with allergies may be more sensitive to molds. People with immune suppression or underlying lung disease are more to fungal infections.

How do you know if you have a mold problem?

Large mold infestations can usually be seen or smelled.

Is Ozone/Ozone Generators a good/effective way to get rid of mold in a building/home?

Generally we do not recommend the use of ozone, nor does the EPA or many independent agencies such as Consumers Union. The reason for this is because Ozone can be very dangerous, and many tests have found that ozone does not kill mold/fungi until it reaches levels that are harmful for humans. Even at that level there is not a guarantee this will kill the mold spores or make them so that humans are not allergic to them.

Information from this page was retrieved from

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Fungal Characteristics Table

Below is a table of information about common mold types, including indoor sources and potential health effects associated with molds This table contains only general health information; if you concerned about the effects of mold on your health, please a qualified physician who specializes in the treatment of mold-health issues, allergies, or asthma.

Key to Abbreviations used for Health Effects:

A = Potentially Allergenic
P = Potentially Pathogenic
T = Potentially Toxic

Genus General Information Indoor Sources Health Effects
Alternaria Common mold in outdoor air; found in soils, on seeds, and on plants; reaches peak in late summer Carpets, textiles, house dust, foods, window frames, and areas of condensation; damp spots around showers and on horizontal surfaces in building interiors A, P, T
Arthrinium Found outside in plant debris and soil Found on water-damaged wood A
Ascospores Plant pathogens with a wide distribution outdoors; spores are released during times of high humidity or rain Able to grow on damp substrates indoors A
Aspergillus Found outside in decaying vegetation, cereal grains, and soil Found in water-damaged carpets, building materials, damp areas, and house dust; able to grow on a wide array of substrates A, P, T
Aureobasidium Typically slowly to moderately-growing mold; found outdoors on plant debris, soil, and woody materials Seen in indoor air A, P
Basidiospores Produced by common mushrooms; agent of dry rot and white and brown wood rot; destroys the structural wood of buildings Found on chronically wet wood materials such as 2x4s under leaky windows A, P
Bipolaris Plant parasite found outdoors mostly in tropical and subtropical regions; found in plant debris and soil; closely related to Drechslera Able to grow on a variety of substrates A, P, T
Botrytis Causes vegetable and ornamental plant disease; found outside in soil, produce, and plant materials; used in making dessert wines Typically associated with indoor plants and water-damaged cellulose products A, P
Chaetomium Found outside in soil and on seeds, cellulose substrates, dung, wood and straw materials Found on substrates containing cellulose (e.g.: paper, sheetrock, plant compost); usually associated with high moisture contents T
Cerebella A brown rot fungus; can damage timber; also known as Coniophora puteana Has been found growing inside on damp materials A, P
Cladosporium Commonly identified outdoor fungus; found outdoors on dead plants, woody plants, food, straw, soil, paint, and textiles Grows on textile, wood, moist window sills, etc. A, P, T
Curvularia Facultative plant and cereal pathogen found outside in plant debris and soil; more common in tropical or subtropical climates, but present in temperate areas Able to grow on a variety of indoor substrates A, P
Drechslera Found outside in soil or on grains, grasses, and decaying foods; closely related to Bipolaris Able to grow on a variety of indoor substrates A
Epicoccum Grows readily outside on decaying plant materials, foods, and soil; commonly causes spots on plant leaves; sporulates quickly Able to grow under low humidity on a variety of substrates A
Fusarium Found outdoors in the soil or associated with plants; can be root pathogens Can be found in indoor air samples P, T
Myxomycetes Grows outside on other fungi and plant materials, including logs, stumps, and leaves; not considered to be a true fungi Can grow indoors on other fungal growths A
Oidium Causes Powdery Mildew in higher outdoor plants; formerly known as Oospora. Occasionally found in indoor air and dust samples A
Penicillium One of the most common fungal genera; typically found outdoors in soil, food, grains, and decaying plant material; one species produces a toxin that is the source of the drug penicillin. Grows in water damaged buildings on wallpaper and glue, decaying fabrics, and moist chipboards. Often found in dust and on spoiled food products. Also able to grow in areas of high humidity. A, P, T
Periconia Parasitic or saprophytic on plant material; found outdoors in soil and on herbaceous plant materials Typically grows in conjunction with other fungi A
Pithomyces Grows on decaying plants and grasses, particularly leaf litter Able to grow on a variety of indoor substrates A, T
Rhizopus Found outdoors in soils, foods, and plant materials; one species is used in fermenting alcoholic beverages Able to grow on decaying materials inside P, T
Rusts Plant parasites that are host-specific to grasses, flowering plants, and trees Readily introduced indoors by wind or physical transport A
Smuts Plant parasites; found outdoors on cereal grains, grasses, flowering plants, and other fungi Readily introduced indoors by wind or physical transport A
Spegazzinia Found outside on plants and in soil Does not usually grow indoors A
Stachybotrys Found outside in soil, plant detritus, seeds, decomposing cellulose, and leaf litter; very rarely found in the air outside; referred to as Toxic Black Mold in the popular media. Grows on building materials high in cellulose and low in nitrogen content (e.g.: wicker, wallboard, jute, paper); requires very high water content for growth A, T
Stemphylium Occurs outside on decaying and living plants and in soil; some species are plant pathogens Commonly found on cellulose materials (e.g.: cotton cloth, livestock feed, ceiling tiles, paper); requires wet conditions A
Torula An ascospore; found outdoors in soil and decaying plant materials. Able to grow indoors on cellulose A
Ulocladium Found in soil and plant materials outside Water-damaged building materials, textiles, paper, and cellulose; commonly found in both air and surface samples A
Ustilago A yeast that can be pathogenic on cereal crops outside; typically slow-growing Detected in both surface and air samples from indoor areas P

This table is based on a table from “Bioaerosols, Assessment, and Control;” ACCGHI, 1999.

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