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Digital illustration of mycotoxins

If you are exploring how to handle a possible mold problem in your home or business, you’ve probably come across the word “mycotoxin.” What are mycotoxins?

A cursory web search doesn’t help much. As of my writing this, these are the first two definitions that Google lists when I search “mycotoxin”:

“A mycotoxin is a toxic secondary metabolite produced by organisms of the fungus kingdom and is capable of causing disease and death in both humans and other animals. The term ‘mycotoxin’ is usually reserved for the toxic chemical products produced by fungi that readily colonize crops”.


“Mycotoxins are naturally occurring toxins produced by certain moulds (fungi) and can be found in food. The moulds grow on a variety of different crops and foodstuffs including cereals, nuts, spices, dried fruits, apples and coffee beans, often under warm and humid conditions”.

WHO, 2018

For anyone trying to understand mycotoxins and their impact on our health, these definitions fall short. I resolve mold issues for a living, and I still find these descriptions needlessly technical and helplessly vague. Furthermore, they don’t give the complete picture. Mycotoxins are present in foodstuffs despite the industry’s best preventative measures.

They can also manifest in buildings as a byproduct of mold proliferation due to water damage.

In this writing, I will do my best to review critical elements of what you need to know about mycotoxins in as digestible a way as possible: What they are, how they affect us, where you might find them, and how to respond when you do.

Table of Contents

  1. What is a mycotoxin?
  2. Where are they found?
  3. Varieties of mycotoxin
  4. How do they enter the body?
  5. Mycotoxin symptoms
  6. Mycotoxin testing
  7. Conclusion

What are mycotoxins?

Let’s start by defining mycotoxins. As we’ve discovered, a cursory web search can provide you with all manner of clinical definitions for the word but generally:

Mycotoxins are chemical agents produced naturally by various species of mold and fungi that are toxic to animals, including humans.


Mycotoxins are toxic chemical substances that certain types of molds produce.  These fungal toxins are volatile organic compounds.

One challenge we face when learning about mycotoxins is that the field of study exploring them is relatively new and research is ongoing. However, there is little debate on the health issues associated with mycotoxins.

Bottom line: Mycotoxins are toxic.

Toxin” Definition:

A poisonous substance that is a specific product of the metabolic activities of a living organism and is usually very unstable, notably toxic when introduced into the tissues, and typically capable of inducing antibody formation.

Where are mycotoxins found?

Because mold and other fungi produce mycotoxins, it stands to reason that you are likely to discover mycotoxins anywhere you might find a species of mold that produces them. Two areas of concern for people are (1) In contaminated food and (2) buildings with a history of water damage and mold problems.

In food

Some studies claim that most cases of mycotoxicosis (mycotoxin-related illnesses) arise from the consumption of mycotoxins in contaminated food. Coffee, barley, oats, wheat, and other high-fiber crops appear among those most commonly cited in the literature. If you worry that you are experiencing mycotoxicosis symptoms and have ruled out building infestation, consider looking into if you have been eating food contaminated with mold or mycotoxins.

Having said that, I won’t use more space in this article exploring mold and mycotoxins in food. Pure Maintenance of Santa Barbara supports good health by restoring the health of homes and businesses, so my focus will be on how mycotoxins affect indoor air quality.

Inside buildings

Indoor air quality is a critical area of concern with respect to mold and mycotoxin exposure. Exposure to mold spores may present a severe health risk that affects upwards of 25% of the population. Essential to understanding health risks or illnesses caused by mold exposure is the notion that mold does not need to be visible for mold spores to negatively impact one’s health and wellness.

That’s right – mold does not need to be visible to be hazardous. How can this be? We will explore the concept of “Total Mold Load” in another blog. For now, all you need to understand is that these mycotoxins and mold spores are microscopic, so you won’t see them, but they nevertheless proliferate in both outdoor and indoor environments. While studies exploring the correlation to so-called “sick building syndrome” stop just short of determining causation, scientific data and anecdotal evidence supporting the dangers of mold, mold spore, and mycotoxin exposure are abundant.

Sick building syndrome” is an informal moniker used to describe the phenomenon in which individuals occupying air-tight indoor spaces suffer from any number of symptoms commonly associated with mold exposure. The symptoms are related to their building (hence the name) because the individuals experience some relief upon vacating the building in question.

This is really important!

I’m going to repeat myself, as this concept is very critical. We commonly think of mold as something fuzzy and black growing on a wall that has been damaged by water. You can “see it” in your mind, right? Ok, have you ever wondered where the mold originated from? Was it in the water? No! The mold spores were already on the drywall in a dormant state. Unplanned water intrusion (typically from a leak or flood), saturated the building component (drywall, in this case) and the microscopic spores became active and grew into that black fuzzy “stuff” you see. The spores were already there, and the conditions became favorable for them to grow.

Are you getting it yet? Mold spores are already there – unseen – to such an extent that approximately 25% of the population is exposed to a hazard that may be adversely affecting their health.

Mycotoxins can be as small as 0.1 microns. For reference, the width of a human hair is 70 microns, and the human eye visibility threshold is about 40 microns. Mold spores are typically between 1 and 20 microns. Mycotoxins typically replicate on and attach to floors or walls in humid and confined environments or on certain foods. However, one can find mycotoxins on any type of surface or material.

Types of Mycotoxins:

Several varieties of mold frequently identified in mold-affected spaces produce mycotoxins. These include Stachybotrys (black mold), Aspergillus, Cladosporium, Alternaria, and Penicillium. 

One class of mycotoxins produced by black mold, called Trichothecenes, can cause acute reactions that include alimentary hemorrhage and vomiting. Ochratoxins, a type of mycotoxins commonly related to Aspergillus mold, is characterized in studies as a kidney & liver toxin, an immune suppressant, and a carcinogen.

I am just barely scratching the surface of the subject. There are dozens of classes of mycotoxins associated with all sorts of mold, each of which presents certain dangers. A person existing in a building with a mold infestation is already experiencing a health risk. As you can see, they may also be at risk of mycotoxin exposure.

How do mycotoxins enter the body?

Mycotoxins typically enter the human body in one of three ways: Ingestion, dermally (through the skin), or inhalation.

A body can ingest mycotoxins by either indirect or direct contamination. Direct contamination occurs when food or feed becomes infected with a toxigenic fungus with subsequent toxin formation.

Indirect contamination can take place when an ingredient of a process has previously been contaminated with toxin-producing fungi and while the fungus itself may be killed or removed during processing, the mycotoxin will mostly remain in the final product. One example of this is in coffee.

Mycotoxins can also enter the body through the skin (dermal) or the eyes. The eyes are actually the easiest and most direct way that they enter the body. If they enter the body through the skin, this is most likely because your body was in direct and recurring contact with a contaminated source such as clothes, linens, or furniture. This is the least common entry point for mycotoxins.

Because mycotoxins often proliferate indoor spaces and pollute indoor air quality, they are also easy to inhale. They make their way through the sinuses or mouth and into the lungs.

Mycotoxins can affect all organ systems, but different varieties sometimes affect specific organ systems as well. Differences among mycotoxin types also relate to the severity of the effect. Some cause primarily acute and highly reversible effects, others cause irreversible organ damage, and others still cause both acute and chronic effects, depending upon exposure levels, time of exposure, and other variables. 

The most commonly induced mycotoxin-related diseases include liver cancer, kidney failure, and effects on the brain or nervous system. The term for the toxic effect of mycotoxins on animal and human health is mycotoxicosis. 

Mycotoxins have four basic kinds of toxicity: acute, chronic, mutagenic, and teratogenic. In addition to these, mycotoxins can be carcinogenic, estrogenic, hemorrhagic, immunotoxic, nephrotoxic, hepatotoxic, dermatoxic, and neurotoxic. (Milićević et al., 2010).

Mycotoxin symptoms

I want to be cautious as I explore possible symptoms related to mycotoxin poisoning because, as I have already mentioned, most studies stop just short of determining causation. This hesitancy is partly due to the challenge of isolating the effects of mold and mycotoxins from other variables that affect human health. These variables include genetic differences, diet, exercise, living environment, medical history, access to routine healthcare, and more. As such, nothing I explore here is medical advice, so please do not take it as such. If you are experiencing symptoms you fear are related to mold exposure, I encourage you to work with your doctor to determine the best course of action.

It is also important to note that exposure to mold does not necessarily suggest exposure to mycotoxins. Mold exposure can be hazardous even in their absence!

These are a few symptoms commonly associated with mycotoxins:

  • Asthma
  • Wheezing and bronchitis
  • Fatigue
  • Musculoskeletal pain
  • Headaches
  • Anxiety, mood, cognitive impairments, and depression
  • Autoimmune reactions

Additionally, research implicates many mycotoxins as carcinogens. This report lists some of the cancers that they may cause:

  • Liver cancer
  • Kidney cancer
  • Esophageal cancer
  • Lung cancer
  • Renal cancer
  • Breast cancer
  • Testicular cancer
  • Stomach cancer
  • Reproductive organ cancer 

Your health matters and solutions exist that mitigate your risk of exposure. That is why Pure Maintenance exists to support your improved health by restoring the health of your home. If you worry you might have mold or mycotoxins in your home or business, give us a call today to find out how we can help.

Mycotoxin testing

If you believe you may be experiencing symptoms of mold or mycotoxin exposure, I encourage you once again to speak with your doctor about the appropriate steps to take. Throughout my work, I have heard of a variety of mycotoxin testing methods, including blood and urine testing. RealTime Laboratories* is one institution that performs mycotoxin urine tests, and they are licensed by the College of American Pathology and the CLIA.

*This is not a recommendation of this lab, and we receive no compensation of any kind for mentioning them. I mention them for no reason but to be as comprehensive in my provision of information as possible.

I will leave the best course of action for you to your doctors. Please speak with a medical professional experienced with mold-related illnesses before purchasing any test or other mycotoxin treatment you may uncover in your search for information.

Where it concerns testing for mycotoxins in an indoor environment, no one test is perfectly conclusive. While there are a couple of ways to test for them in the home, the preferred and most accurate method is through dust sampling.

How long are mycotoxins toxic?

Mycotoxins are toxic for a very long time. According to experts, trichothecene mycotoxins can remain toxic for several years. Some researchers have suggested that trichothecene, as one example, can remain toxic for over a decade.

How do you kill mycotoxins?

Mycotoxins aren’t actually alive like mold spores. So when we talk about killing them, we really mean breaking down (denaturing) mycotoxins and their toxicity so they are no longer dangerous to humans. They are very resilient, however. For example, it requires 500 degrees Fahrenheit (260 degrees Celsius) for half an hour or 900 degrees Fahrenheit (482 degrees Celsius) for 10 minutes to destroy trichothecene mycotoxins.

Other methods, such as ozone treatment, supposedly destroy most or all mycotoxins. However, the level of ozone you need to eradicate them is not safe for humans. Alternatively, ultraviolet light or freezing temperatures do not have much effect on mycotoxins.

Furthermore, HEPA air filters are not effective at removing mycotoxins. Activated carbon filters can remove them from the air. Mycotoxins do eventually break down and lose their toxicity after some time. Trichothecene mycotoxins are among the most resilient and can take years to break down.

The Pure Maintenance treatment process, on the other hand, has demonstrated notable efficacy – verified in published scientific literature specific to mold and other pathogens – whereby we accomplish eradication via a process known as lysis. Lysis (or cellular disruption) is an effect in which the outer boundary or cell membrane breaks down or disintegrates in order to release inter-cellular materials such as DNA, RNA, protein, or organelles from a cell. The end result of our process (using peracetic acid vaporization in this case) disrupts the cell molecular conformation and the consequence of denaturation is loss of biological activity.


Mycotoxins present a real and severe health threat. You may be exposed to mycotoxins through contaminated food or a mold infestation in your home or another building you frequently occupy. In either case, speak to your doctor should you be experiencing any health effects and take appropriate steps to end your exposure to mold and mycotoxins! If you are in Santa Barbara or San Luis Obispo Counties, we can help. Give us a call today to discuss the ways we can support you on your path to more complete wellness.