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Do You Know Of Specific Blood Tests For Molds?

Question: My husband and I were exposed to extremely high levels of Aspergillus (indoor count 33,000 ppm-outdoor count 400-500 ppm), Stachybotrys, Penicillium, Chaetomium, Cladasporium and a few others…

This exposure was over a period of 2 1/2 years. We didn’t know the mold was in our home and we and the doctors could not explain or diagnose our symptoms (ie: bleeding noses, flu like symptoms, chronic fatigue, aches and pains…just to name a few). We both have tumors (lungs, liver, ovaries). Do you know of specific blood tests available in Canada to test for the molds listed above. We have been tested for Cryptococcus gatti but realize that this is not for all mold types. Our doctors are unwilling to accept the idea that the molds in our home caused our symptoms or made us sick. Please, can you help?

Answer: Were the spore counts reported as parts per million (ppm)? Mold spore counts are usually reported as spores per cubic meter of air and not as parts per million (ppm). That’s beside the point. You wanted to know whether there are specific blood tests available in Canada to test for the molds Aspergillus, Stachybotrys, Penicillium, Chaetomium, and Cladosporium. I believe there are, although I don’t know who is doing it. The tests may not be available for some species.

The test is based on mold-specific antibodies. The presence of antibodies in the blood only indicates that one has been exposed to mold at some time. It does not indicate when one was exposed, where the exposure took place, or how much of mold one was exposed to. Therefore, a positive test for mold-specific antibodies alone is generally not enough to prove that health effects reported by individuals in moisture-damaged buildings are caused by exposure to mold.

Are These Levels of Spores Considered Hazardous?

Question: The crawlspace in our condo has the following readings for spores/m3 : Aspergillus/Penicillium type-16000; Chaetomium- 67; Cladosporium- 227. Are these levels spores considered hazardous? It is going to cost a very high amount to have vents, sensors and spores removed to correct the situation and there is no guarantee. Please give me your comments on this.

Answer: There are no published standards for acceptable exposures to indoor mold spores. And there is no agreement among the scientific community on the exact levels of airborne indoor mold spores which are responsible for the onset of disease, nor is there adequate information on dose-effect relationship.

This is what Health Canada advises:

Health Canada considers that mould growth in residential buildings may pose a health hazard. Health risks depend on exposure and, for asthma symptoms, on allergic sensitization. However, the large number of mould species and strains growing in buildings and the large inter-individual variability in human response to mould exposure preclude the derivation of exposure limits. Therefore, Health Canada recommends:

  • to control humidity and diligently repair any water damage in residences to prevent mould growth; and
  • to clean thoroughly any visible or concealed mould growing in residential buildings.

These recommendations apply regardless of the mould species found to be growing in the building.

Further, in the absence of exposure limits, results from tests for the presence of fungi in air cannot be used to assess risks to the health of building occupants.”

For more information regarding mold spores please call us at 905-290-9101 in Ontario or 604-435-6555 in British Columbia.

Chaetomium species as indoor contaminants

Chaetomium species

Chaetomium globosumChaetomium species are found worldwide in soil, dung, or decaying plants. Most species are prolific producers of the enzyme cellulase that breaks down cellulose. Destruction of paper and other materials containing cellulose (including foods, feeds, paper, textile, bird feathers, seeds and military equipment) by species of this mould is well documented. Due to their strong ability to destroy material, Chaetomium species are often used in testing materials for resistance to mould growth.

Chaetomium is perhaps the third most common indoor fungal contaminant of mouldy damp buildings. It may be found on wet drywall, wall-paper, carpets, window frames, baseboards and plywood. The most widespread and common species is Chaetomium globosum. This species causes many problems of biodeterioration of paper and other cellulose containing material. It is considered a “weed” of mushroom beds, where it inhibits the growth of cultivated mushrooms.

Chaetomium as a contaminant of indoor air

Generally the concentration of airborne Chaetomium spores is very low. This is because the spores (= ascospores) are produced within flask-shaped bodies (= perithecia) and not exposed to air like those of moulds such as Penicillium and Aspergillus. When the spores mature, they are released inside the perithecium and then squeezed out in a column like toothpaste through an opening at the top of the perithecium. The coiled hairs trap the spores such that they are not easily dispersed into the air by wind.Chaetomium globosum spores

The other reason why the concentration of airborne Chaetomium spores is usually low is because the spores are relatively large and hence have relatively high settling rates and therefore do not remain airborne for long. As a result, airborne spore concentration of Chaetomium is usually low even in contaminated buildings. Due to low air concentration, exposure to airborne Chaetomium is insignificant except in situations where the mould has dried out and disturbed.

What does the presence of Chaetomium in a building tell us?
Chaetomium is one of those moulds that require chronic moisture conditions for it to grow. It’s presence is therefore an indication of existing or previous serious moisture problem. A few spores in pre-remediation air samples is an indication of a mould problem in the building. Because of the low airborne concentration, rarely is Chaetomium detected in outdoor samples. Hence any spores detected indoors are highly likely to have a source indoors and not outdoors. One can also sample house dust to determine whether Chaetomium is present or not.

Health Effects

Although Chaetomium species are rarely associated with human infections, there are reports of infections involving individuals with weak immune system. Chaetomium globosum is known to produce 2 toxins in moisture damaged buildings, chaetoglobosins A and C. These toxins have the potential to cause illness to building occupants.

For more information on Chaetomium species,please visit http://www.moldbacteria.com/learnmore/moldlist.html or call 905-290-101.

References

  1. Fogle, Matthew R (2007). Growth and mycotoxin production by Chaetomium globosum. PhD Dissertation, Texas Tech University Health Sciences Center.
  2. Udagawa S, Muroi T, Kurata H, Sekita S, Yoshihira K, Natori S: Chaetomium udagawe: a new producer of sterigmatocystin. Trans Mycol Soc Jap 1979, 20, 475-480.
  3. Domsch KH, Gams W, Anderson T-H: Compendium of Soil Fungi. Academic Press, London 1993.
  4. Arx JA von, Guarro J, Figueras MJ: The Ascomycete Genus Chaetomium. J. Cramer, Berlin 1986.
  5. Barron MA, Sutton DA , Veve R, Guarro J, Rinaldi M, Thompson E, Cagnoni PJ, Moultney K, and Madinger NE, Invasive Mycotic Infections Caused by Chaetomium perlucidum, a New Agent of Cerebral Phaeohyphomycosis. Journal of Clincal Microbiolgy, Nov. 2003, p. 5302–5307 Vol. 41, No. 11
  6. Piecková E: In vitro toxicity of indoor Chaetomium Kunze ex Fr. Ann Agric Environ Med 2003, 10, 9–14.

Mold On Books

Books are prone to dampness if the relative humidity is not maintained below 60%. Prolonged damp conditions results to mold growth on the paper and on the bindings. Mold growth on books leads to damage of books through staining and or breaking down of paper and other book components. Besides the damage, many molds isolated from books are a health hazard capable of causing serious respiratory diseases and allergies of various degrees. Molds commonly isolated from moldy books include species of Aspergillus, Penicillium, Cladosporium, Trichoderma, Chaetomium, Stachybotrys, Epicoccum and a number of others. Trichoderma, Chaetomium, and Stachybotrys are strong producers of the enzyme cellulase that breaks down the paper.

Procedure for cleaning moldy booksMold growth on a book

If the books are not extensively damaged (i.e, the paper is still intact), they can be saved. Below is a brief procedure that can be used to clean moldy books.

  • Workers must wear appropriate personal protective equipment when handling contaminated books. This includes wearing coverall or other protective coat over street clothing, a respirator (i.e. N95 or better) and vinyl examination gloves. Unprotected individuals risk aggravating or developing allergic sensitivities to the mold spores.
  • Cleaning must be conducted within a temporary containment unit away from air intakes, other building openings and public areas.
  • Moldy books must be HEPA vacuumed on the following areas: outside front and back covers, joints between the covers, spine, text block and inside back and front covers. A soft-bristled brush may be used to remove stubborn mold growth. (NB: Care must be taken not to damage the books).
  • Once cleaning of books is completed, book carts that were holding moldy books must be cleaned with disinfectant and paper towels. Refer to the material safety data sheets (MSDS) of the disinfectants before use.
  • Before re-shelving, the cleaned books must be given a quick wipe down with an appropriate disinfectant solution, the floors and shelf areas must be cleaned and disinfected and the shelves and flooring must be cleaned with disinfectant and paper towels.
  • After completing the cleaning, the exterior of the HEPA vacuum cleaner is wiped down with a disinfectant to kill any settled spores.
  • Workers must remove protective coveralls, eye protection, respirator, and gloves outside and wash hands with soap and hot water after completing the cleaning session.
  • A record of where the problem areas are, the cause of the problem, a list of the cleaned books, the time and day when the cleaning took place must be kept for future reference.
  • Implement a preventative cleaning program to address the continuing mold problem in the library.

Types Of Mold

Many people often ask what are the types of mold commonly found indoors. Generally the prevailing conditions determine the types of mold prevalent in a given environment. A highly humid environment is likely to be dominated by those molds that require a lot of water such Aspergillus fumigatus, Chaetomium globosum, Stachybotrys chartarum, Ulocladium chartarum, Fusarium solani, Trichoderma sp, while a relatively dry environment may be dominated by those molds that require less moisture to grow such as Aspergillus versicolor, Eurotium spp, and Wallemia sebi. For a more detailed discussion on the types of mold commonly found indoors and their hazard classes, visit the website http://www.mouldfacts.ca/mouldtypes.html.

If you have a question concerning indoor mold or bacteria, give us a call at (905)290-9101.

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