Some people say, "There's nothing harmful about mould, it's everywhere!" Well, that statement is partially true: mould can be found everywhere on earth, from pole to pole.
So when does mould become an issue for our health and wellbeing?
This article discusses four factors: mould sensitivity, mould species, mould quantity and mould activity.
1. Mould sensitivity
Some individuals are particularly sensitive to mould exposure, experiencing allergic reactions or respiratory problems when exposed to even small amounts of mould. Common symptoms of mould sensitivity include sneezing, coughing, wheezing, watery eyes, and skin rashes. More serious are symptoms of chronic fatigue, multiple chemical sensitivity and chronic inflammatory response syndrome (CIRS). An estimated 24% of the population has genetic susceptibility to mould-related illness. For sensitive (and hypersensitive) individuals, the presence of mould can range from uncomfortable to debilitating.
2. Mould species
While mould comes in various species, certain types can be more problematic than others. For instance, Stachybotrys chartarum, commonly known as "toxic black mould" is one of the most notorious species due to its production of mycotoxins (toxic chemicals produced by mould). Other common moulds that produce mycotoxins include Fusarium, Aspergillus, Penicillium.
3. Mould quantity
Although mould is present in almost every environment, the quantity of mould can determine whether it becomes a problem. When mould colonies grow and multiply, they release more spores into the air, increasing the likelihood of inhalation and exposure. You know you have excess mould when it is visible (remember mould is microscopic).
4. Mould activity
First, let's make one thing clear: mould can cause harm to health whether it is "dead" or alive. That's why it is so important to remove mould rather than kill it (more on that in another post).
However, if mould is actively growing in your home, you know the problem is getting worse. Indicators of active mould growth include the presence of hyphae in your mould testing sample, high counts on an ATP meter, and musty smell (microbial volatile organic compounds, MVOCs).
Research is ongoing regarding the potential negative health impacts of exposure to MVOCs.
Conclusion
While mould is a naturally occurring organism found everywhere, it can become a problem due to its potential health effects. Degree of mould sensitivity, varying mould species, the quantity of mould present and the activity of mould all play a role in determining the impact it has on our well-being.
Understanding these factors and taking necessary measures to prevent and address mould growth is essential for maintaining a healthy living and working environment. This field can be confusing and full of myths - hiring an expert can help.
References
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