Fungi/mold/mould are nature’s natural decomposers. They are ubiquitous in all environments and humanity has developed buildings for their indoor environments which may become the perfect breeding grounds for mold growth when water, high humidity and a food source is present.   

A water-damaged building (WDB) is a building with a long-term water problem that has constant dampness or moisture. The result of this dampness/moisture has created the perfect environment for the growth of biological matter such as bacteria and mold to proliferate creating toxic microbial matter, toxic by-products and volatile organic compounds.

Fungi include mold, mushrooms and yeasts. Mold requires moisture, oxygen, light and food to grow. The food required can be building materials or dust. Some molds produce odours due to the production of MVOCs. Unviable and viable mold spores contain mycotoxins originating from the spores and hyphae, when inhaled can be allergenic and toxic. Mold can cause allergic reactions and inflammatory reactions in certain individuals. Mold contamination in building materials usually occurs after 48hrs  (US EPA 2001).

Biotoxins such as bacterial endotoxins and fungal mycotoxins can trigger a chronic inflammatory response causing multiple symptoms such as fatigue, shortness of breath, cognitive/memory impairment, muscle weakness, issues with balance or coordination, anxiety, depression and light sensitivity (DiTulio, 2015). These symptoms and their immunological and inflammatory responses are classified as Chronic Inflammatory Response Syndrome (CIRS) and typically require the toxins to be bound before removal (DiTulio, 2015).

More than 90% of occupants in a water damaged building are affected with fatigue(Shoemaker and Maizel, 2009; J H Brewer et al., 2013). A high percentage of the chronic fatigue suffers have mycotoxins detected in their urine (Joseph H. Brewer et al., 2013). Further to this, WDB occupants also suffer from neurological deficits and upper or lower respiratory diseases (Brewer, Thrasher and Hooper, 2013). Further to this, there are strong associations of respiratory effects such as wheeze, cough, bronchitis, allergic rhinitis, eczema and multiple asthma-related effects such as development and exacerbation(Fisk, Eliseeva and Mendell, 2010; Mendell et al., 2011).

Water damaged buildings also harbour the increased growth of dust mites, bacteria and bacterial endotoxins (Hope, 2013). Fungi, dust mites, cockroaches and rodents are common indoor allergens that can cause allergic respiratory diseases and asthma (Pomés, Chapman and Wünschmann, 2016). Dust mites in particular have been associated with diseases such as rhinitis, atopic dermatitis and asthma (Pomés, Chapman and Wünschmann, 2016). There are also causal relationships of asthma development to exposure to dust mite allergens via inhalation (Krieger et al., 2010).