Dr Jackson Kung'u- Mold Specialist

Helping People Resolve Mold Problems

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Dr. Jackson Kung’u (PhD)- Mold Specialist.
Phone: 905-290-9101

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Allergy

Mold Allergy Symptoms

Allergies can be caused by one or possibly a combination of many different things including an array of triggers such as food, medicine, environmental factors and inhalants.  Allergies are among the most common chronic conditions worldwide.

Mold allergy symptoms vary from one person to another and range from mild to severe.  Mold spores and very fine hyphal fragments trigger allergic reactions in about 20% of the adult population. The reactions are due to protein and polysaccharide components of molds. The smaller the spores and the finer the hyphal fragments the easier it is for them to penetrate deep into the respiratory tract. In humans mold allergy symptoms are of two types, the immediate hay-fever or asthma Type I and the delayed farmer’s lung Type III. Type I allergy occurs only in allergic individuals and may be caused by many types of molds including plant pathogens. Alternaria and Cladosporium spp., are two of the common molds causing seasonal mold allergies of this type.

Mold allergy symptoms can include sneezing, nasal congestion and itchy or watery eyes. People who suffer from Asthma may experience wheezing and shortness of breath. Some people may experience mold allergy symptoms all year round while in some others symptoms would flare up only during certain seasons of the year depending on what triggers the allergy or the amount of allergens present in the environment. Mold allergy symptoms are significant when the weather is damp, and when indoor or outdoor spaces have high mold spore concentrations.

People who are sensitive to mold can experience mold allergy symptoms both indoors and outdoors. For example in summer and fall several types of molds thrive on dead leaves and release spores into the air. On inhaling these spores, individuals who are sensitive to mold spores are likely to experience allergic reactions.

Controlling mold allergy means controlling your exposure to mold. That isn’t always easy outdoors. But you can limit exposure inside your home by controlling mold growth, cleaning up existing mold growth, and to some extent preventing outdoor mold from infiltrating indoors.

Health Effects of Mold

All molds are potentially a health hazard. While majority of common molds are not a concern to individuals who are healthy, the health effects of most of the indoor molds are not known. Some symptoms associated with mold exposure are also highly controversial. Health effects of mold include:

1. infection;

2. allergic reactions (i.e., allergy);

3. mycotoxin poisoning.

 Infection

Infection of healthy individuals by indoor molds is very rare. Occasionally, however, immunocompromised individuals may be infected by some opportunistic pathogens such as species of Aspergillus, Penicillium and Fusarium.

Allergic Reaction

It’s estimated that about 20% of the human population is allergic to normal spore concentrations. The rest 80% would require exposure to higher spore concentrations. Health effects of mold partly depends on the amount of mold an individual is exposed to. However, with the large number of mold species and strains growing in buildings and the large inter-individual variability in human response to mold exposure it’s hard to define what is “normal” or “high” mold spore concentration.

Mycotoxins

Apart from infections the most well known health effects of mold is mycotoxin poisoning. Some common molds such as Aspergillus flavus, Stachybotrys chartarum, Fusarium, Alternaria, Paecilomyces, Rhizopus, Trichoderma, and Trichothecium produce substances (mycotoxins) that are toxic to humans, animals or other microorganisms. A number of mycotoxins are not only toxic but are also highly potent carcinogens. Spores of toxin producing molds contain mycotoxins. Majority of mycotoxins are not volatile and therefore mycotoxin exposure is likely to occur through inhalation of spores and dust. Evidence that inhaled mycotoxins affects human health is circumstantial.

Minimizing Exposure To Mold

The best way to deal with the health effects of mold is to minimize exposure to mold. Exposure to mold can be minimized by improving the indoor air quality. Here are some steps one can take:

  • Controlling humidity and letting more air into the house by ensuring sufficient ventilation. This prevents moisture from building up on walls and windows. If there is excessive humidity, mechanical ventilation such as a fan may be needed to get rid of it.
  • Measuring humidity by using a hygrometer to see if a de-humidifier is needed. The relative humidity should be kept below 50% in summer and 30% in winter.
  • Repairing leaky roofs, walls, and basements.
  • Cleaning moldy surfaces with a detergent.
  • Keeping the house clean and dust-free.
  • Regularly cleaning and disinfect humidifiers, de-humidifiers, and air conditioners.

If you have a question regarding health effects of mold, contact us at 905-290-9101.

Mold Spores Contribute To Respiratory Disease And Allergic Reactions

It’s well established that airborne mold spores contribute to respiratory disease and allergic reactions in humans. Mold spores are everywhere and we inhale them every minute both when we’re indoors and outdoors. In cold countries airborne mold spores is highest during summer. During winter, the spore concentration outdoors is very low or absent altogether. In warm countries concentration of airborne spores may vary with the season (rainy or dry season) but there are spores present outdoors throughout the year. Usually the spore concentration indoors is lower than outdoors. However, in buildings with mold problem, the spore concentration could be very high.

Allergic reactions caused by mold spores

Inhaled mold spores can cause a number of health problems. Susceptible individuals react to proteins in the spore wall resulting in development of runny nose and eyes (allergic rhinitis) and asthma-like symptoms. Prolonged exposure to unusually high levels of spores can result in the development of allergic alveolitis.

Allergenic mold Spores

Spores commonly associated with allergy outdoors include spores of Cladosporium, Sporobolomyces, Didymella, and Alternaria. In buildings without mold problems, the same spores found outdoors would be present indoors but in lower levels than in outdoors. In buildings with mold problems a mix of species commonly found indoors and outdoors would be found. The indoor species would be in higher concentrations indoors than in outdoors.

In an indoor occupational environment the types of molds present would be determined by the indoor conditions and the work being carried out. For example in a compost facility thermotolerant fungi such as Aspergillus fumigatus would be present. Mold spores of some species such as Cladosporium and Penicillium may be detected in high numbers in air samples while others such as Eurotium, Wallemia, and Penicillium may be abundant in dust.

Exposure limits to black mold

Many times we’re asked the exposure limits to black mold. Unlike other indoor pollutants, there are no exposure limits to mold. Exposure limits to mold would be difficult to set because human beings differ in their susceptibility to mold. Similarly, the molds themselves differ in their ability to cause health problems.

Molds may affect human beings in three different ways:

  • Allergenicity
  • Infection
  • Toxicity

As concerns common indoor molds the most likely effect is allergenicity. Very few fungi (molds and yeasts) are known to cause infection to healthy individuals. Toxicity is most likely to occur if one eats food contaminated with the fungal toxins. While toxicity is also possible through inhalation of spores or dust containing toxins, little is known about this possibility. 

Generally, elderly people, infants, sick people and other individuals with weak immune systems are at higher risk of suffering from mold exposure related diseases than healthy people.