Mold, a common type of fungus, is found in nearly every environment, both indoors and outdoors. It thrives by breaking down organic matter, playing a role in natural decomposition processes.
Mold’s Metabolic Activity
As a living organism, mold engages in cellular respiration, a process that generates energy for its growth. During this process, mold converts nutrients into usable energy, with carbon dioxide (CO2) as a natural byproduct. This release of CO2 is continuous, similar to how humans produce CO2 through respiration. The amount of CO2 released correlates with the mold’s metabolic rate and growth; active, widespread colonies produce more.
Factors Affecting Mold Activity
The rate at which mold grows and produces CO2 is influenced by several environmental conditions. Moisture is the most critical factor, as mold requires water to thrive and often grows optimally in areas with high humidity or dampness. Organic materials such as wood, drywall, and fabric serve as food sources, while moderate temperatures (65-80°F) also play a role. Oxygen is generally required for mold’s cellular respiration. When these conditions are favorable, mold growth accelerates, leading to increased CO2 production.
CO2 Contribution in Context
While mold does produce CO2 as part of its metabolic activity, its contribution to overall indoor CO2 levels is generally minor. Typical household activities, such as human breathing, significantly impact indoor CO2 concentrations, often raising levels above the average outdoor 400 ppm to over 1,000 ppm. Other sources, like gas appliances or pets, also release substantial amounts of CO2. Unless there is an extremely large mold infestation, the CO2 produced by mold is usually insignificant compared to these common household emitters. Elevated indoor CO2 levels are typically an indicator of poor ventilation rather than a sign of a significant mold problem.
Other Indoor Air Quality Concerns
Beyond CO2 production, mold presents other, more significant concerns for indoor air quality and human health. The primary risks stem from the release of microscopic mold spores, fragments, and volatile organic compounds (VOCs). Mold spores are reproductive units that can become airborne and, when inhaled, may trigger various health responses, including allergic reactions like sneezing, itchy eyes, or respiratory issues. Some molds also produce VOCs, often detectable as a musty odor, which can irritate the eyes, nose, and throat. These compounds can contribute to discomfort and, in some cases, more serious health effects.