Mold Toxicity: What to Know About Mold & Mycotoxins

There’s a lot of confusion around mold toxicity and the health impacts of mold exposure, as most people associate mold-related illnesses with allergies and respiratory symptoms. However, the signs and symptoms of mold sickness — a complex biotoxin illness that differs from mold spore allergies — are much more widespread. Because of this, mold illness is often undiagnosed and untreated or misdiagnosed as something else entirely. 

In this blog, we’ll discuss the many health effects of mold toxicity: an overexposure to mold spores and the harmful metabolites they produce. 

Mold toxicity: what are mycotoxins?

Unlike mold allergies — or immune reactions to mold spores — mold illness describes a non-allergic response to mold exposure. It’s a hypersensitive or toxic reaction to mold and the harmful metabolites they produce. These toxic metabolites are known as mycotoxins.

For example, ochratoxin A (OTA) is a mycotoxin produced by certain species of Aspergillus and Penicillium molds. This mycotoxin is frequently detected in the urine of patients with mold illness, and it’s the most commonly seen mycotoxin on Mosaic Diagnostics’ MycoTOX Profile.

Ochratoxin A is often present in water-damaged buildings and certain foods and beverages such as dried fruit, grains, beer, and coffee. It can be absorbed in the body via inhalation, oral ingestion, or through the skin. 

Wellness tip: If you drink coffee, look for coffee beans that have been third-party tested for mold and mycotoxins. 

Some Aspergillus and Penicillium molds also produce other mycotoxins such as gliotoxin, aflatoxins, sterigmatocystin, and mycophenolic acid (MPA). Mycophenolic acid suppresses the immune system, which is why it’s used pharmaceutically to produce immunosuppressive drugs. Ochratoxin A and gliotoxin are also shown to suppress the immune system, while gliotoxin and aflatoxins have been associated with immune toxicity. 

Other mycotoxins in foods and water-damaged buildings

Fusarium, Stachybotrys, and Chaetomium molds can also produce toxic metabolites that disrupt mitochondrial function, suppress the immune system, damage organs, and increase the risk of cancer. These and other mycotoxins are commonly found in water-damaged homes, vehicles, offices, and schools, especially in environments with high indoor humidity. 

Other common sources of mycotoxins include foods and beverages such as:

• Wine (gliotoxin).
• Beer (ochratoxin A).
• Coffee (ochratoxin A).
• Peanuts (aflatoxins).
• Nuts (aflatoxins).
• Spices (aflatoxins).
• Dairy (aflatoxins and mycophenolic acid).
• Grains (aflatoxins, sterigmatocystin, macrocyclic trichothecenes, mycophenolic acid, and zearalenone).
• Cereal grains (enniatin).
• Corn (zearalenone and enniatin).

That said, not everyone exposed to mycotoxins via food or water-damaged buildings will develop mold toxicity or symptoms of mold illness. Some individuals may experience allergy symptoms when exposed to mold (e.g. respiratory issues like sneezing or coughing), while others may not react to mold at all. Other patients — especially those genetically susceptible to mold toxicity — can become severely ill as a result of mold exposure. 

Mold: can it make you sick? 

About 24 percent of the population is genetically susceptible to mold toxicity. This puts about a quarter of people at an increased risk of getting sick from prolonged mold exposure and developing symptoms of mold illness.  

This is because variations in human leukocyte antigen (HLA) genes — specifically HLA-DR and HLA-DQ alleles — are associated with an increased susceptibility to mold toxicity and an impaired ability to eliminate mycotoxins from the body. For this reason, patients with variations in HLA genes can also take longer to heal from mold toxicity even after starting treatment. 

Keep in mind, however, that genetics aren’t the only risk factor for mold toxicity. You can still develop mold toxicity without having variations in HLA genes, though your risk may be lower. 

Common mold toxicity symptoms include:

• Persistent fatigue.
• Headaches.
• Cognitive issues (e.g. memory changes, brain fog, and poor concentration).
• Respiratory issues (e.g. coughing, watery eyes, and sinus discomfort).
• Pain and weakness.
• Skin rashes and skin sensitivity.
• Abdominal issues (e.g. abdominal pain, nausea, and diarrhea). 

Nearly any organ or bodily function can be impacted by mold toxicity, with neurological, respiratory, and immunological symptoms being some of the most common. One study of 100 patients exposed to mold in their homes found that 80 percent had abnormalities in T and B cells, 70 percent experienced neurological dysfunction, and 65 percent experienced respiratory symptoms. Musculoskeletal, gastrointestinal, and cardiovascular symptoms were also reported among these patients. 

Mold illness: the great imitator

Even when patients present with signs or symptoms of mold illness, identifying, diagnosing, and treating mold toxicity is no easy feat. Since mold toxicity is a “great masquerader” that mimics other conditions, a comprehensive patient intake and in-depth and specialized testing are needed to rule out other conditions with overlapping symptoms. 

It’s not uncommon for mold illness to be misdiagnosed as an autoimmune disease, mental health condition, fibromyalgia, irritable bowel syndrome (IBS), or attention-deficit/hyperactivity disorder (ADHD), as symptoms of mold sickness tend to overlap with these conditions. For example, overlapping symptoms often include fatigue, brain fog, unusual aches and pains, concentration issues, headaches, abdominal pain, night sweats, and mood changes. 

Mold illness can certainly co-occur with these and other medical conditions, but mycotoxin exposure could be the underlying root cause (or trigger) for some patients. In these cases, mold and mycotoxins must be addressed in order to restore health.