Understanding Mold

Molds are species of fungus that play a vital role in decomposing organic matter in nature. As a home or business owner, understanding mold and its effects are very important. Because molds do not require sunlight to grow, they thrive in low light areas by decomposing organic matter such as cellulose, starches and paper materials.

Mold reproduce by means of microscopic seeds called spores. These spores are ejected from the main mold structure similar to how trees or flowers repopulate by spreading seeds. If the mold spores don’t immediately find a source of food or water, they can lay dormant for a number of years. Once the right mixture of moisture and temperature are reached, these spores become active and quickly spread.

Mold Spores

Scientists classify spores as viable and non-viable. “Viable” meaning that the spores are capable of growth. “Non-viable” meaning unable to reproduce. It’s important to note that non-viable spores can still emit toxins that can be harmful for inhabitants. The safest way to deal with spores – viable or non-viable – is the use of mold abatement chemicals and the effective removal of the spores from the home.

A Hidden Threat

People often question if mold actually poses a threat, since it is always present in our outdoor environment. Extensive research shows that mold becomes dangerous to humans when it’s contained within a building or living space. Poor air circulation and indoor moisture allows the concentration of mold to reach dangerous levels. Concentration levels not typically seen in an open air, outdoor environment.

It’s also vital to understand that 60% of homes that contain dangerous concentrations of mold show no visible signs of mold growth. This is because mold typically grows in the dark and damp areas of your home – such as a crawlspace, inside walls, underneath carpet or in the attic. Residents typically smell a mold problem before they see one, because growing mold spores produce an unmistakably musty odor.

A common misconception is that newer buildings are immune to mold contamination. A poorly built new home is just as susceptible to mold growth as a 60 year old home. In our experience, we’ve seen mold in home six months after their completion. Usually these problems are a result of inadequate foundation work, improper storing of building materials, poor ventilation systems and building design flaws.

It’s also worth noting that the air flow design of buildings has changed dramatically because of the energy crisis in the 1970s. Buildings constructed after the 70s typically are more air tight to minimize the inward and outward flow of air. While this lowers energy costs, it also keeps fresh outdoor air from entering the building and replacing old, stale air that likely carries dust and mold spores.

Types of Mold

While not all are allergenic or toxic, here’s a few common harmful indoor molds:

  • Aspergillus
  • Penicillium
  • Fusarium
  • Alternaria
  • Stachybotrys
  • Cladosporium


Mycotoxins are the poisons produced by molds. The EPA states that mycotoxins can be ingested, inhaled or absorbed through the skin – all with harmful effects. Here are a few examples of the most harmful mycotoxins produced by indoor molds:

  • Trichothecene – the most harmful mycotoxin
  • Aflatoxin – a strong carcinogen
  • Fumonisin – contaminates grains and foods
  • Ochratoxin – linked to urinary tract tumors