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Mold – What is it and should you be concerned?

All living things fall into one of five Kingdoms. Molds are in the Kingdom Fungi, which includes mushrooms, yeasts and molds. Molds will grow anywhere there is moisture, oxygen and an organic food source. It is estimated that there are more than 100,000 species of fungi. Primarily, fungi are saprophytic microorganisms. In other words, they are a part of the ecological system that recycles dead organic material back into usable nutrients for other forms of life. They share this decomposing activity with certain bacteria. It has been estimated that without these saprophytic microorganisms, the surface of the planet would be covered with a pile of debris that could reach five miles high. The planet would be uninhabitable. Molds produce tiny spores to reproduce, just as some plants produce seeds. Spores are ubiquitous, meaning that they are everywhere. They can be found in both the indoor and outdoor air, and settled on indoor and outdoor surfaces. When mold spores land on a surface that is damp or wet, they may begin growing and digesting whatever organic material is present in order to survive.

Molds have played an important role in the development of certain medicines and in food production. Penicillin was derived from a species of Penicillium. Similarly, the antibiotics known as cephalosporin and cyclosporin were derived from other molds. Prior to penicillin being available, an infection, even from a simple scratch, might have led to amputation or death.

Other species of Penicillium are responsible for the flavors of various cheeses such as Danish Blue, Roquefort, Camembert, Brie and Gorgonzola. Other molds are used in the production of sausage and soy sauce. Yeasts such as Saccharomyces cerevisiae are used in the baking and brewing industries. Botrytis, otherwise known as the “noble rot”, enhances the sweetness of grapes in wine production.

When Mold Becomes a Problem
As you can see, molds play an important and friendly role in maintaining a healthy ecology. But they can, at times, become a foe instead of a friend. While mold spores are everywhere, when the kinds, location and quantities reach levels that have the potential to cause harm to humans they become a foe. The potential adverse reactions from exposure to molds include sensitivities, allergies, asthma, disease and toxic reactions. Many individuals suffer from allergies due to common outdoor molds. In some cases, these allergic reactions trigger an asthmatic reaction. According to the Department of Health Services State of California the “Typical symptoms that mold-exposed persons report (alone or in combination) include:

  • Respiratory problems, such as wheezing, difficulty breathing, and shortness of breath
  • Nasal and sinus congestion
  • Eye irritation (burning, watery, or reddened eyes)
  • Dry, hacking cough
  • Nose or throat irritation
  • Skin rashes or irritation

Headaches, memory problems, mood swings, nosebleeds, body aches and pains, and fevers are occasionally reported in mold cases, but their cause is not understood.” The types and severity of symptoms depend upon the types and amount of molds present, the extent of exposure and the individual’s sensitivities.

In most cases, people with a properly functioning immune system can be exposed to large amounts of mold with little or no reaction. Even if there are symptoms after a severe exposure, they will usually dissipate after the person leaves the contaminated environment. It is similar to being exposed to the sun. Each person has a different level of tolerance. Some will sunburn very easily and others can remain in the sun for longer periods of time with little or no effect. If you begin to sunburn, you can move into the shade and in time the sunburn will diminish.

Some people may have more severe symptoms or become ill more rapidly than others. Those that may be more susceptible to exposure include the elderly, infants, pregnant women, individuals with respiratory problems, allergies, and asthma and those individuals that have a suppressed immune system.

It has been well documented that certain occupational environments are of concern. Wood pulp-worker’s lung has resulted from working in wood pulp processing plants. Likewise, workers in wood chip factories have developed wood chip burner’s lung or greenhouse lung; cheese factory workers have developed cheese worker’s or cheese washer’s lung; sawmill workers have developed wood trimmer’s disease and individuals working around moldy hay have developed farmer’s lung.

Why a Growing Concern
Molds that grow in the indoor environment such as homes, schools and offices are also a growing concern. Recently there have been many newspaper articles written about schools being closed for repair and homeowners that have vacated their homes due to extensive mold growth. Why now? After all, hasn’t mold been around forever?

There are many reasons why mold problems in buildings have become more prevalent. One reason is that in recent years buildings are being built with materials that are more “mold susceptible.” An example is the replacement of lathe and plaster with drywall. The inner core of drywall, also called gypsum board, holds moisture. The paper on drywall is an excellent food source for mold. If building interiors and wall cavities stay wet for extended periods of time, it allows mold spores to germinate and grow. In the United States prior to the 1970s, buildings were not as well insulated or airtight. Buildings got wet and dried out faster than they do today. In the 1970s the United States experienced a fuel and energy crisis. The consequence for the building industry was that buildings started to be designed that were more airtight and better insulated. Energy conservation was achieved by reducing the airflow, heat loss or heat gain through the building envelope. At the same time the building’s ability to dry out, when it became wet, was reduced. Buildings stay wet longer from moisture intrusion and mold has a greater opportunity to grow.

As the number of buildings that were energy efficient started to increase, the number of mold problems also began to grow. As reports of school closures and homeowner health problems became newsworthy, the more frequently the media chronicled their conditions. Today it is common to hear about this widespread problem.

The solution to mold problems is simply to keep your home and workplace clean and dry. When moisture problems occur, act promptly to dry things out thoroughly. Doing this can spare you and your family from the unfriendly side of mold.

Molds are an essential part of a healthy ecology. Without them our planet would be uninhabitable. They enhance our enjoyment of our food and drink. Some molds have been useful in preventing disease. When molds are allowed to grow out of control, they can become a health problem.


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