Mold Exposure and Sickness

Mold refers to thread-like structures typically observed on a substratum in various shapes, sizes and colors due to the growth of filamentous fungi. Filamentous fungi are a group of saprophytic or parasitic organisms under the fungal or plant kingdom that lives decomposing and absorbing the organic material in which they grow. Mold is ubiquitous in nature and can be reported from both indoors as well as outdoors from air, surfaces and fluids. Mold growth is common in damp, hot and humid places especially where rich organic matters are available. In indoor places, typically they grow near moisture, such as around leaks in roofs, windows, pipes or where there has been a flooding episode. It can grow on a variety of substrates such as paper, cardboard, ceiling tiles, wood products, fibers, leather, dust, paints, insulation, drywall, carpet and other household articles rich with organic or inorganic materials.

Common Types of Indoor Environmental Mold

• Acremonium
• Aspergillus
• Alternaria
• Aureobasidium
• Bipolaris
• Chaetomium
• Cladosporium
• Curvularia
• Fusarium
• Mucor
• Penicillium
• Rhizopus
• Trichoderma
• Ulocladium

Infrequent Types of Indoor Environmental Mold

• Absidia
• Cuninghamella
• Exophiala
• Geotrichum
• Gliocladium
• Helminthosporium
• Microsporum
• Nigrospora
• Paecilomyces
• Pithomyces
• Scopulariopsis
• Sporothrix
• Stachybotrys
• Syncephalastrum
• Trichophyton
• Verticillium
• Walmia

Mold Exposure

Exposure to damp and moldy environments may cause a variety of health effects especially those who are sensitive to it. Inhalation, contact and ingestion are identified as a main route of mold exposure. Inhalation is identified as one of the most prevailing mechanism of exposure from viable or nonviable mold structures including mycotoxins. The airborne mold particulates are essential for inhalation exposure. The aerosolization of mold spores and structure in indoor environment is a common phenomenon by which they perpetuate in the air.

Surficial mold in high or frequently touched surfaces are a main source of contact exposure. The level of actively growing mold on the surfaces are directly related to moisture and the nutritional availability in ecological niches. The dormant structures of mold in surfaces are the resultant of residual or settling fungal structures. Ingestion exposure of mold is not very common in comparison to the other two mechanisms, however, it happens due to eating mold infested food. Ingesting toxins that molds produce can cause disease. Long term ingestion of aflatoxins (produced by Aspergillus species) has been associated with hepatocellular cancer. In addition, ingestion of high doses of aflatoxin in contaminated food causes aflatoxicosis and can result in hepatic failure. Some food materials such as meat, poultry, vegetable, etc. are infected with mold/fungus and can also contain mycotoxins.

Mold Sickness

Mold exposure can cause a range of health related issues in susceptible individuals. The symptoms of mold sickness may be chronic or acute. Some common symptoms of mold sickness are nasal stuffiness, throat irritation, coughing or wheezing, eye irritation, lethargy, in some cases, skin irritation etc. Mold can infect the lungs and cause asthma, COPD, hypersensitivity pneumonitis etc. Mold can also initiate a number of allergenic disorders, dermal, nail, scalp and other body parts infection.

In 2004 the Institute of Medicine (IOM) found there was sufficient evidence to link indoor exposure to mold with upper respiratory tract symptoms, coughing and wheezing in otherwise healthy people; asthmatic symptoms in people with asthma; and hypersensitivity pneumonitis in individuals susceptible to that immune-mediated condition. The IOM also found limited or suggestive evidence linking indoor mold exposure and respiratory illness in otherwise healthy children.

In absence of a universally accepted practice to determine mold levels in occupiable spaces, a few basic approaches are beneficial for determining and understanding the issues related to mold exposure. It is encouraged to properly manage occupiable space ventilation, relative humidity and temperature under the threshold (30-60% and 68-79°F, respectively) to minimize the mold growth. Initial screening for mold in occupiable spaces can be performed using Do-It-Yourself test kits. When the screening test indicates a positive result, then a building health check is encouraged which includes a proper diagnosing, testing and remediation of the existing mold issues to avoid the exposure and related illness.

For more info on mold in the indoor environment or to get started with mold testing please call 1-800-422-7873, ext. 304 or contact us via this page.