A Force of Nature To Be Reckoned With

Somewhere in history, mold as a pathogen has fallen into obscurity. It can be ascertained by reading in the Bible where it 500 BC. printed that mold in houses was seen as unclean and was not accepted at all. It is not until the last 40 years that mold exposure in indoor environments has once again become a hot issue. It has probably been well known for millennia that mold can be very harmful.

It was only during the 20th century that mycotoxin, also called mold poison, became known. Briefly described, the research started in the 1930s and received a further boost in the 1960s when more mold toxins were discovered.

In relation to the amount of studies that are based on oral intake, the studies that examine the effects when inhaled are few. Therefore, it is not yet possible to set limit values ​​for tolerable inhalation exposure to mycotoxins.

Most consumers are unaware of the exposure to toxic molds infested in their homes, office or schools. But most of the time, these microorganisms are difficult to detect because their development is not visible macroscopically and their detection requires a specific mycological analysis.

Unfortunately, some types of mold can cause damage to humans and animals, and their toxicity is not limited to their multiplication, indeed they are also toxic indirectly through the mycotoxins they produce.

Unfortunately, often underestimated by homeowners, the harm caused by these mycotoxins to the human body is diverse and can range from acute intoxication to chronic fatigue. It can also cause allergic reactions or an increased predisposition to certain cancers.

So, what are these mycotoxins? What are their types and how do they damage our health? How can we detect them? And above all, how can we protect ourselves from them?


Mold species and their toxins

There are today approx. 400 known toxins that in certain cases and situations are emitted from mold species such as Aspergillus, Fusarium, Stachybotrys and Penicillium. These species are known to be found in mold-affected houses. Different species of Aspergillus form Aflatoxin, which is one of the most dangerous toxins known to cause cancer and many other diseases and ailments. Various species of Aspergillus and Penicillium form Ochratoxin, which is suspected of causing cancer as well as damaging the liver, kidneys and immune system. Fusarium forms T-2, Tricothecene which is a more directly lethal poison when exposed to large doses. T-2 also causes serious and permanent damage. Fusarium also forms the mold toxins Fumonisin, Vomitoxin and Zearalenone, where Fumonisin caused "mad horse disease" where pigs and horses were affected in the USA by having their brains badly affected.

What are Mycotoxins?

Mycotoxins are toxic chemicals produced by fungi and mold that are some of the most prevalent toxins in the environment. Mycotoxins are metabolites produced by fungi like mold, which can infest buildings, vehicles, and foodstuffs.

Most mycotoxin exposures in North America, Europe, and Australia are through airborne exposure. Food may be a major source of mycotoxins in third-world nations that lack government inspection of foods, especially the grains such as rice, corn, wheat, rye, and barley.

Many grains that are harvested are contaminated with mycotoxins, but little of such harvests are discarded and are frequently sold for animal feeds such as dog food or feed for cows, pigs, chickens, turkeys, and horses.

Fungi can grow on almost any surface, especially if the environment is warm and wet. Inner wall materials of buildings, wall paper, fiber glass insulation, ceiling tiles, and gypsum support are all good surfaces for fungi to colonize. These fungi then release mycotoxins into the environment causing symptoms of many chronic diseases.

Diseases and symptoms linked to mycotoxin exposure include fever, pneumonia-like symptoms, heart disease, rheumatic disease, asthma, sinusitis, cancer, memory loss, vision loss, chronic fatigue, skin rashes, depression, ADHD, anxiety, and liver damage.

They have been linked to a variety of health effects in humans and animals. When mycotoxins enter the food supply, they can wreak havoc at every point along the chain—affecting everyone from farmers to grain mills to consumers of the grain. The grain supply is particularly susceptible because grains can become contaminated with mycotoxins during crop growth or during grain storage, establishing a need to test for mycotoxins at every stage in the food supply chain.

The diseases caused by mycotoxins are called mycotoxicosis. Another name for these illnesses is Chronic Inflammatory Response Syndrome or CIRS. The mycotoxins’ effects can be either acute or chronic depending on several factors, including the degree of susceptibility or sensitivity of the individual, the toxicity level of the mycotoxin, the individual’s age and overall health, and the duration or repetition of the exposure.

What Are Mycotoxins?

Mycotoxins are toxic substances originating from the secondary metabolism of different types of fungi such as FusariumAspergillus and Penicillium.


Among hundreds of known mycotoxins, aflatoxins (AFs), ochratoxin A (OTA), fumonisins (FBs), zearalenone (ZEA) and trichothecenes (DON, T-2, HT-2) are considered the major mycotoxins in animal production. The variety of clinical effects caused by mycotoxins after ingestion ranges from reduced performance, suppressed immune function, organ damage, reduced gut health and nervous and reproductive system problems and depend on the type of mycotoxin, its dosage and the animal species. Significant economic losses are associated with mycotoxins due to their impact on animal performance.

Only a handful of mycotoxins with known toxicity effects are regulated and the regulatory levels are inconsistent and vary from country to country. Because mycotoxins are compounds, they inherently change the chemical composition of the product and cannot be removed, isolated or simply washed off.

Specific mycotoxins are historically known to cause illness and disease such as immune suppression in both humans and animals.

Generally, these compounds are produced by mature molds that develop from weather conditions during the growth stage in the fields and/or storage and transport conditions after harvest. Different combinations of weather patterns and storage environments are conducive to certain mold strains thriving and multiplying.

During the mold life cycle is when mycotoxins are thought to be metabolized and formed. More mold growth is a good indicator of increased toxin production and, consequently higher levels of contamination.

Types of Mycotoxins

Mycotoxins are produced by just over 360 species of mold, mostly belonging to the type of Aspergillus, Fusarium, and Penicillium. Mycotoxin product happens fast, and it does not take long to spread. They have a low molecular weight and are most often thermo-stable in non-aqueous medium, and therefore difficult to degrade. In most cases, they can survive in food even after mold elimination.

There are several hundred types of mycotoxins, but the most harmful ones with toxic effects on our health are Aflatoxins, Ochratoxin A, Patulin, Fumonisins, Zearalenone, and Nivalenol. They appear in the food chain because of the contamination of crops by molds, these toxins can also contaminate human beings by air. Even if they are mostly known for long-term harmful effects, such as immune deficiency or cancer, mycotoxins can also expose to immediate complications such as acute intoxication.

Where are Mycotoxins Found?

According to the World Health Organization, mycotoxins are toxic compounds naturally produced by certain types of molds (fungi). They grow on either on the floor or walls in a humid and confined environment or on some foods. Mold growth can occur before or after harvest, during storage, on or in the food itself, often in a hot, humid and moist environment.

Mycotoxin Testing and Detection

Exposure to mycotoxins is a serious issue that many people do not realize is impact their health until it is too late!

If you find mold growth or suspect you may have mycotoxins in your body it is important to get tested and begin treatment as soon as possible.

Mycotoxin poisoning and illness looks different in everyone and looks similar to other conditions like chronic fatigue syndrome.

Types of Mycotoxins


A family of fungi strains that affect plant products, aflatoxins have been linked to liver cancer, hepatitis, cirrhosis, and other health issues. Exposure occurs when consuming contaminated plant products, eating meat or dairy from animals that have eaten contaminated feed, or inhaling dust while working with contaminated products.

  • Aflatoxin B1 – Of the four aflatoxins that cause cancer in humans and animals, aflatoxin B1 is the most toxic, and is classified by the World Health Organization as a class 1 carcinogen. Though it primarily attacks the liver, this mycotoxin can also affect the kidneys, lungs and other organs.
  • Aflatoxin B2 – Like aflatoxin B1, aflatoxin B2 is produced by the fungi Aspergillus flavus and A. parasiticus. It’s also a toxin and carcinogen that contaminates food products, primarily affects the liver and kidneys and enters the body through the lungs, mucous membranes (nose and mouth), or even the skin, but is less potent than aflatoxin B1.
  • Aflatoxin G1 – Born from a soil-borne fungus like the other aflatoxins, G1 also contaminates a wide range of food products including peanuts, cottonseed meal, oilseeds, vegetable oils, corn, and other grains in human food and animal feed. Aflatoxin contamination is most common in humid environments, especially tropical and subtropical regions.
  • Aflatoxin G2 – The least toxic aflatoxin, G2 is still dangerous to humans and animals. Though less lethal than some of the other aflatoxins, G2 can also cause liver problems (including cancer, chronic hepatitis, and jaundice) and appears to play a role in Reye’s syndrome. Like all aflatoxins, it can also adversely affect the immune system.


Produced by at least five types of fungi, this group of mycotoxins includes around 170 types of toxins. Some types contaminate plants, including grains, fruits, and vegetables. Others thrive in soil and decaying organic material. Several types of trichothecenes are infamously produced by Stachybotrys chartarum, also called black mold.

  • Satratoxin G – Though all of the trichothecenes are highly toxic, tests have determined that Satratoxin G is the most dangerous to people and animals. The black mold Stachybotrys chartarum produces several types of trichothecenes, but produces Satratoxin G and H in greater amounts than other toxins.
  • Satratoxin H – Not all strains of black mold (Stachybotrys chartarum) produce mycotoxins, but the ones that do typically produce more than one kind, including Satratoxin H. The mold is found on some agricultural materials, and in damp or water-damaged environments. Evidence suggests the mold is a serious problem in North America.
  • Isosatratoxin F– Another trichothecene mycotoxin produced by Stachybotrys chartarum, Isosatratoxin F is one of the contributors to “sick building syndrome,” where health issues of building occupants are directly tied to time spent in mold-infected buildings. A 1984 World Health Organization Committee report suggested that up to 30 percent of new and remodeled buildings are possible causes of health problems due to poor air quality.
  • Roridin A – Like other macrocyclic trichothecenes, Roridin A is produced by mold, and is associated with a number of acute and chronic respiratory tract health problems. Experiments have shown that exposure to Roridin A can cause nasal inflammation, excess mucus secretion, and damage to the olfactory system.
  • Roridin E – Like many of the mycotoxins, Roridin E can cause the above respiratory and olfactory issues, and may also disrupt the synthesis of DNA, RNA, and protein, which can impact every cell in the body. Roridin E grows in moist indoor environments, but can also be produced by a soil fungus that contaminates foodstuffs, and is passed down the food chain to animals and then to humans.
  • Roridin H – Affecting human and animal health in much the same ways as other trichothecene mycotoxins, Roridin H is produced by mold, especially Stachybotrys chartarum, which grows well on many building materials subject to damp conditions, including wood-fiber, bards, ceiling tiles, water-damaged gypsum board, and air conditioning ducts.
  • Roridin L-2 – This mycotoxin is also produced by molds, including black mold. Interestingly, environmental tests cannot always detect Stachybotrys, since its spores are large and heavy and not easily dispersed into the air. Unfortunately, mycotoxin molecules, including the very toxic Rorodin l2, are light and easily airborne and inhaled by occupants of an infected building.
  • Verrucarin J – Yet another mycotoxin produced by Stachybotrys chartarum,Verrucarin molecules are small enough to be airborne and easily inhaled. Experiments have determined that inhalation is the most dangerous form of exposure, but trichothecene mycotoxins can easily cross cell membranes, which means they can also be absorbed through the mouth and even the skin.
  • Verrucarin A – One of the most toxic trichothecenes, Verrucarin A is also produced by fungi and mold. Like Roridin E, Verrucarin A is found not only in molds in damp environments but also in molds that occur naturally on a variety of crops intended for human and animal consumption.


  • Gliotoxin – The most common cause of mold diseases in humans is Aspergillus fumigatus, which produces gliotoxin, a mycotoxin that suppresses the immune system. Found in many homes and buildings, A. fumigatus typically only infects individuals with compromised immune systems but can be deadly: Invasive Aspergillosis (IA) is the leading cause of death in immunocompromised people.
  • Ochratoxin A (OTA) – A toxin produced by different Aspergillus and Penicillium species — is one of the most-abundant food-contaminating mycotoxins. It is also a frequent contaminant of water-damaged houses and of heating ducts. Exposure can also come from inhalation in water-damaged buildings.

Mycotoxins As Airborne Aerosols In Your Home

In the past, scientists and pundits have said that mold toxins [1] are not easily transported from the infestation surface into the air in a house, and that mold [2] does not always, or more rarely, produce toxins. At the same time, some of these people have tried to show that the amounts of mycotoxins that we in sick houses [3] inhale are so low that they cannot cause health effects. In 2007, this attitude changed to some extent through Swedish care via Lund University and the discovery that mold poisoning in damp-damaged houses was far more common than previously thought. [1,4] The debate flared up when a person, seen by public society as an expert, formally kicked the rear and said that despite the new findings from the university, there was nothing to worry about. This nay-saying party had indeed invested a lot of money in finding out that there were no risks. However, no actual study was shown. The critic was also careful to point out that the researchers at the university were not doctors and therefore could not comment on health risks. [5]

Now a further study has been carried out which proves that the researchers in Lund were right. The poisons from the mold are easily spread from the point of attack itself into the air. It is not only via the mold spores that the mycotoxins are spread, but also via dust and very small fragments, so small that they pass far down into the airways and lungs. The study from France is based on a controlled experiment in which an indoor environment with growth of mold on wallpaper is simulated. Three mold species, Aspergillus versicolor, Stachybotrys chartarum and Penicillium brevicompactum were included in the test. The experiments showed that the poisons changed into aerosol form at certain air flow speeds, i.e. that ventilation and air circulation in houses can control how much is released from the site of attack. The gist of the observations is that the exposure must be weighed into further studies where the intention is to find out what it is that makes people sick in houses with current problems. [6,7]

We already know that there is more than ventilation speed and air movement that affects how much metabolites are released from a place with mold. The amount of moisture in both air and material, air pressure and temperature, where the mold growth is in the house's climate shell, etc., are other factors. The French study does not address factors such as these. Here we see a research gap that will hopefully be filled.

Another research gap is how the mold toxins affect our health when inhaled. The French point out that their findings are important for further risk assessment and evidence for the possible emergence of later toxic effects after inhalation. No clear relationship between dose and response has yet been established. However, it has been shown that intranasal exposure to the mycotoxins Satratoxin and Tricothecenes from the black mold Stachybotrys chartarum can be highly toxic, with several potentially serious health effects, e.g. neurological. [8-11,29]

Visible mycotoxin-emitting mold in housesAlthough it is important to study, it is not possible to lock yourself away from mold spores and mold toxins. Damp-damaged houses mean that the air is variably contaminated with different chemical substances and more bioaerosols than mycotoxins. For example. emitted from microbial attack MVOC - Microbial Volatile Organic Substances. Recently, suggestions have come from Professor Joan W. Bennett that these, often odorous [12] substances, can be called Volatoxin, as they exhibit harmful effects in experimental trials. [13] More and more are suggesting that myotoxins as well as other substances released by molds and bacteria need to be given more attention. The science bank is growing [14] despite naysayers trying to cast the subject in controversial guises. Not least, the evidence is strengthened that children and adults who stay in a house damaged by damp and mould, actually gets worse through various symptoms and developing a wide range of health effects as well as lifelong illness. [15-17]

Mycotoxin aerosol from crawl space

From the crawl space [18], mycotoxins, volatoxins etc. can enter through passages for pipes, via the gap between floor and wall, etc. places, be aerosolized into the house. We have encountered this phenomenon thousands of times during inspections and moisture measurements and mapped it through analyzes and odor samples. A crawl space without a dehumidifier can be seen as a risky construction, where in case of leaks due to pressure differences between the crawl space and the living space, bioaerosols like mold poison can easily be transported. Up in the house there can be continuous or seasonally varying negative pressure. Negative pressure means that not as much air is added as is drawn out through the ventilation. [19,20] Then "leak air" is taken from the crawl space. Bacteria and mold aerosols accompany the air. For us, this phenomenon is self-evident. Among other thingsCrawl space contaminates the indoor environment – ​​mold and bacteria . [21]

There are more risk constructs [22] that follow this crawl space example. Basements [23] and older types of slabs on the ground [24] are often affected by moisture and microbes. The same applies to the house's attic, although it is relatively less often that mycotoxin aerosols etc. find their way directly into the home from the attic. [25] In connection with our receiving information about the French studies on mycotoxins, further new knowledge was found where Uppsala University publishes a summary of the so-called " SBS - Sick Building Syndrome ", symptoms and health effects related to the overall poor condition of Sweden's property stock/single-family homes are in. This reinforces the information that substances that negatively affect the indoor environment are added from moisture-damaged places in houses, such as crawl spaces, basements and slabs on the ground. [26]

Returning to the research that exists around mold toxins, it is seen as relatively strong and elaborated regarding exposure intake via food and drink. Here it is established that mold toxins such as Aflatoxin are carcinogenic. More mold toxins are classified lower as suspected of causing cancer. A wide range of other health effects have also been researched. [15,27] As we interpret it, luck has now come to find out more about the exposure effects after inhalation. The not entirely public MYCOMIX project shows that different mycotoxins together can have an additive effect, even in low doses. Through the information available in MYCOMIX, it was suggested that moisture-damaged houses should also be considered as an additive source of mycotoxins. [28] We can only agree. This should be common sense. The concept of common sense should also include that lower exposure amounts of mycotoxins over time have the potential to cause a chronic toxicological effect. [30]

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