Mold is a type of fungus grown in multicellular filaments on moist food and other surfaces. While generally thought to be an outdoor problem, mold contamination in buildings is quite common.1, 2, 3, 4, 5, 6, 7, 8 One study from Harvard University (Cambridge, Massachusetts), in 13,369 white children aged 8 to 12 years from 24 communities across North America, reported that the prevalence of indoor mold growth was between 22% to 57%, affecting >50% of households in 5 communities. The reported prevalence of asthma symptoms ranged from about 3% to 11% of the children.9 Another study in 5951 children from 9 cities in Russia reported positive associations between water damage or the presence of molds in the home and asthma, wheezing, dry cough, bronchitis, and respiratory allergy.10
Many studies describe the adverse health consequences of mold-contaminated indoor environments, and especially mycotoxins,11, 12 on the skin and respiratory systems.13 Some indoor molds, including Trichoderma, Fusarium, and Stachybotrys spp, produce mycotoxins,1, 2, 3, 4, 5, 6, 7, 8, 14exposure to which occurs through dermal contact, inhalation, and ingestion.11 Inhabitants of affected dwellings typically report headaches and respiratory and musculoskeletal symptoms.9, 15, 16, 17 Some studies have also reported that mold-exposed groups had altered neurologic functioning, including changes in body balance, blink-reflex latency, visual fields, reaction time, and color discrimination, compared with controls.18, 19, 20, 21 The exposed groups also demonstrated depression.22
Increasing evidence has implicated the pathogenic potential of nanoparticulate fragments of fungi, and more specifically mycotoxins.23, 24, 25, 26 Moreover, while a single mycotoxin may not produce any effect, a combination of mycotoxins could induce toxicity at very low levels.27 The major classes of mycotoxins include ochratoxin (A, B, and C), produced by Penicillium and Aspergillus spp, as well as the trichothecenes (T2).14 Ochratoxin A is the most common mycotoxin found in foods and water-damaged buildings, and has been associated with serious health problems,28 including severe neurologic issues, in humans.29, 30
The trichothecene mycotoxins are subclassified as nonmacrocyclic, produced mostly by Fusarium spp, and macrocyclic, produced mostly by Myrothecium, Stachybotrys,and Trichothecium spp. Trichothecene mycotoxins can be released at ~300-fold the concentration of spores.24 These are commonly detected in the air of contaminated buildings, and exposed persons have significantly more T2 mycotoxins in their sera as compared to controls.25, 31, 32, 33 These toxins can cause multisystemic effects, including gastrointestinal, cardiovascular, and neuropsychiatric complications.23 One study reported neurotoxic effects on human cells exposed to satratoxin A at levels found in water-damaged buildings.34Trichothecene mycotoxins released by Stachylobotrys spp, such as satratoxins G and H, have been shown to produce neurotoxicity in humans.35, 36 The nonmacrocyclic T2 fumonisin B1 has also been associated with neurotoxicity.37
Here we review the risk factors, signs and symptoms, diagnoses, and mechanisms of action of mycotoxins, especially as they relate to neuropsychiatric effects.
About the Author
Emily Rachal is co-owner of Texas Mold Inspectors, (or TMI), along with her husband, in the Houston, TX area. After her family’s devastating experience that not only injured her whole family, but also resulted in the loss of their youngest son Malachi, she and her husband have dedicated their lives to now educating and assisting families affected by toxic mold with their state-licensed mold inspection company.
Emily is the founder and owner of MAM. Additionally, she has recently started a non-profit organization in the name of her youngest son, called Malachi’s Message Foundation, to aid in financial support and offer hope to families who feel isolated and are unable to afford all the complex obstacles of overcoming a toxic mold exposure.