Asthma & Molds

19 Jan

Asthma & Molds

Asthma, an inflammatory disorder of the airways, is one of the most common chronic respiratory conditions affecting Canadians. Physicians have diagnosed more than 2.3 million Canadians as being asthmatic—8.4 per cent of adults (Statistics Canada, 2009) and 13.4 per cent of Canadian children (Garner, 2008).

While the exact cause of asthma is unknown, it appears to result from a complex interaction of predisposing factors (tendency to have allergies), causal factors that may sensitize the airways (such as animal dander, dust mites, mold, cockroaches and workplace contaminants) and contributing factors, such as tobacco smoke during pregnancy and childhood, respiratory infections and indoor and outdoor air quality (National Asthma Control Task Force, 2000).

Management of asthma involves the individual, his family and his physician. Asthma specialists recognize the importance of avoiding or controlling known environmental factors, or “triggers,” that aggravate asthma. Triggers include biological pollutants, such as mold, house dust mites and pollen, as well as irritating pollutants, such as nitrogen oxide, ozone and formaldehyde (Canadian Asthma Consensus Group, 1999). For some individuals, avoiding allergens (substances that produce allergic reactions) can be the most important element of asthma management. The National Asthma Control Task Force recommends a management plan that includes reduction of aeroallergens, molds, tobacco smoke, vehicle and industry emissions, noxious odours and scents that can trigger asthma episodes. The Canadian asthma consensus report, 1999 says that increasing medication should not be a substitute for avoiding exposure to allergens and irritants.

This article deals with reducing your exposure to causal and contributing factors in the home. It provides a global approach consistent with the recommendations of the National Asthma Control Task Force and the Canadian asthma consensus report, 1999. The recommendations are aimed at reducing exposure to allergens and other substances that are known to have a potential impact on respiratory health and indoor air quality.
When allergens are involved, elimination is preferable to reduction, since even very small amounts can provoke symptoms. Although evidence of an association between the development or worsening of asthma and some nonallergenic contaminants, such as volatile organic compounds (VOCs), is lacking, the Institute of Medicine (2000) suggests that it is prudent to limit exposure where practical.

The importance of thorough vacuuming House dust is a reservoir of dust mites, fungal glucans (cell wall components) and bacterial endotoxins. As exposure to these potential allergens occurs when house dust becomes airborne, it is important to reduce house dust as much as possible. A recent CMHC study demonstrated that this can be challenging. The study found that four to five successive vacuuming sessions with a High-Efficiency Particulate Air (HEPA) filter-equipped vacuum cleaner, at a rate of one minute per square metre for carpets and half a minute for non-carpeted areas, were required to significantly reduce the amount of fine dust in the homes tested.

Molds

Molds are microscopic organisms that grow on wet or damp surfaces. Under normal circumstances, preventing moisture from reaching high levels in your house is the only way of limiting mold growth. To control the growth of molds, the RH should be low enough to prevent moisture condensation on windows. This may mean 35 per cent RH or less.

Exposure to indoor mold is associated with an increased prevalence of asthma-related symptoms, such as chronic wheezing, irritation symptoms and non-specific symptoms. Asthma-like responses, inflammatory responses in the lungs of rodents and severe histological and biochemical changes have been observed in laboratory animal studies. Health Canada considers mold growth a health hazard and recommends controlling dampness and cleaning up mold regardless of the type of mold.

There are several no-cost and lowcost measures:

  • If your house has a crawl space with a dirt floor, cover the floor with a continuous sheet of 6–12 mil (0.15–0.30 mm) polyethylene. Signs of potential moisture and rodent problems are more visible on opaque sheets of white polyethylene than on clear or black ones. Overlap and tape any seams.
  • Make sure water from your roof runs away from your house by having downspouts lead away from the foundation.
  • Ensure that the ground around your house slopes away from the house.
  • Run a dehumidifier in your basement, even if you have an air conditioner. An air conditioner dehumidifies only when it is running, which may be only a small fraction of the time.
  • Do not keep mold-susceptible items, such as paper, cardboard and clothing, in your basement. They absorb moisture and can grow mold.
  • Carpets in the basement or bathroom are likely places for molds to grow. It is best not to have carpets in these areas.
  • Do not hang clothes to dry in the basement. Use a clothes dryer vented to the outside.
  • Do not store firewood inside the house.
  • Reduce the number of house plants. Watering them is a source of moisture. The soil can be a source of molds.
  • Do not humidify unless absolutely necessary. First, measure the RH with a hygrometer. Readings of 25 to 35 per cent in the winter are generally acceptable. For information about buying and using a hygrometer.
  • If you need humidity at night, use a portable humidifier in your bedroom. Monitor the RH and cycle the unit on and off as necessary. Air the room out to dry during the day. Clean the humidifier after each use. Check windows for condensation and wipe up as necessary.
  • When you shower or bathe, use the bathroom fan and let it run for 15 minutes or longer after you are finished.
  • Bathroom and kitchen fans should exhaust outside.
  • When cooking, use the kitchen fan to get rid of moisture and odours.
  • Do not leave areas of the house unheated. Cold, unheated or damp areas in the house are likely to get moldy. Excessive thermostat setbacks at night may also encourage mold growth.
  • Act immediately if there is a leak or a flood. Solve the problem, then remove and dry wet flooring, walls, furnishings and other belongings. Discard what you cannot dry.
  • Clean up small areas of mold yourself.
  • Get professional help if there is a lot of mold.
  • Deal with dirt floors, crawl spaces and cold cellars.
  • Keep potentially mold-laden dust to a minimum by vacuuming with a HEPA vacuum or central vacuum exhausted to the outside.

Contact your REALTOR at Coldwell Banker Vantage Realty for more tips and advice on keeping you safe in your home.

Reference

Bibliography
Canadian Asthma Consensus Group. (1999). Canadian asthma consensus report, 1999. Canadian Medical Association Journal, 161, Supplement 11. Retrieved March 2009, from http://www.cmaj.ca/cgi/ reprint/161/11_suppl_1/s1
Canadian Partnership for Children’s Health & Environment. (2005). Child Health and the Environment— A Primer. Toronto, ON, Canada: CPCHE. Retrieved March 2009, from www.healthyenvironmentforkids.ca
Garner, R. & Kohen, D. (2008). Changes in the prevalence of asthma among Canadian children. Ottawa, ON, Canada: Statistics Canada. Retrieved May 2009, from http://www.statcan.gc.ca/bsolc/olc-cel/olc-cel?lang=eng&catno=82-003-X200800210551
Health Canada. (2000). Air Cleaners Designed to Intentionally Generate Ozone (Ozone Generators)—Questions and Answers. Ottawa, ON, Canada: Health Canada. Retrieved March 2009, from http://www.hc-sc.gc.ca/cps-spc/house-domes/electron/cleaners-air-purificateurs-eng.php
Health Canada. (2007). Residential Indoor Air Quality Guidelines: Moulds. Ottawa, ON, Canada: Health Canada. Retrieved March 2009, from http://www.hc-sc.gc.ca/ewh-semt/pubs/air/mould-moisissure-eng.php
Institute of Medicine. (2000). Clearing the Air: Asthma and Indoor Air Exposures. Washington, DC: National Academic Press. Retrieved March 2009, from http://books.nap.edu/books/0309064961/html
Jarvis D., Chinn S., Luczynska C., & Burney P. (1996). Association of respiratory symptoms and lung function in young adults with use of domestic gas appliances. Lancet, 347 (8999), 426-31.
National Asthma Control Task Force. (2000). The Prevention and Management of Asthma in Canada: A Major Challenge Now and in the Future. Ottawa, ON, Canada: Public Health Agency of Canada.Retrieved March 2009, from http://www.phac aspc.gc.ca/publicat/pma-pca00/About Your House