What Science Says About Mycotoxins

What Science Says About Mycotoxins

What are Mycotoxins?

  1. “…Mycotoxins are toxic compounds that are naturally produced by certain types of molds (fungi)…” (2) i.e. when the mold eats the food it excretes mycotoxins, similar to when yeast in beer eats glucose and excretes alcohol. Mycotoxins...are made by fungi as a by-product (consequence) of metabolism (living). It is these by-products and not the fungi themselves that are poisonous (15).
  2. Mycotoxins were only seriously studied from the 1960’s on (4, 7) so are a relatively new science.
  3. Mycotoxins have caused serious issues for humans for centuries with many deaths throughout history. Throughout history, particularly in times of famine, wars, and floods, mycotoxins caused outbreaks that sometimes devastated human populations (6).

What are the main Mycotoxins to be aware of in terms of risk to safety?

  1. While over 300 mycotoxins have been identified, about 20 have been shown to occur naturally in foods and feeds at significant levels and frequency to be of a food safety concern. The most commonly occurring mycotoxins are aflatoxins (B1, B2, G1, G2, M1), ochratoxin A, patulin, citrinin, sterigmatocystin, and the fusarium toxins namely fumonisins (B1, B2 and B3), T-2 and HT-2 toxins, zearalenone, nivalenol, and deoxynivalenol (13).
  2. With regard to coffee – the most relevant ones are Aflatoxins (B1, B2, G1, G2), and Ochratoxin A.

How serious are Mycotoxins?

  1. It is important to note that although mold is easy to eradicate/kill via heating etc. the mycotoxin produced by mold is very hard to remove once on the food. Most mycotoxins are chemically stable and survive food processing (2).
  2. Aflatoxins are genotoxic carcinogens and are the most toxic of the mycotoxins. The most common mycotoxin found in human food and animal feed is Aflatoxin B1 - it is the most potent hepatocarcinogen recognized in mammals and listed as Group I carcinogen by IARC (1). Aflatoxin B1 is the most potent natural carcinogen known and is associated with both toxicity and carcinogenicity in human and animal populations. The diseases caused by aflatoxin consumption are loosely called aflatoxicoses. Acute aflatoxicosis results in death; chronic (long-term at lower dose) aflatoxicosis results in cancer, immune suppression, and other “slow” pathological conditions (3). Aflatoxins can even cross the placenta so pregnant mothers should be wary when eating possible foods containing them (8). To recapitulate, there is no other natural product for which the data on human carcinogenicity are so compelling (7). Aflatoxin's reputation as a potent poison may explain why it has been adopted for use in bioterrorism. There is substantial evidence that Iraq stockpiled aflatoxin to be delivered in missiles (7).
  3. The International Agency for Research on Cancer (IARC) has also categorized Ochratoxin A (OTA) as “possibly carcinogenic” to humans i.e. a Group 2B carcinogen. OTA is associated with kidney diseases, such as Balkan endemic nephropathy (BEN), and upper urothelial tract cancer. Recent studies have also shown that OTA can trigger autism via an epigenetic mechanism. OTA also alters nutrition absorption in the intestine and renders the gut vulnerability to infection (1). Ochratoxin A has also been shown to inhibit mitochondrial ATP production (mitochondria convert your fuel into useable energy), and also stimulates lipid peroxidation - a process in which free radicals "steal" electrons from the lipids in cell membranes, resulting in cell damage (the end-products of lipid peroxidation may be mutagenic and carcinogenic) (7). Ochratoxin A is a nephrotoxin (toxic agent or substance that inhibits, damages or destroys the cells and/or tissues of the kidneys) to all animal species studied to date and is most likely toxic to humans, who have the longest half-life for its elimination of any of the species examined (7).
  4. Acute toxicity from mycotoxins is rare: toxicity due to mycotoxins is almost always insidious, without any overt indication of effects on health in the short term. For this reason, the health effects of mycotoxins are among the most neglected areas of medical science (4). Acute toxicity generally has a rapid onset and an obvious toxic response, while chronic toxicity is characterized by low-dose exposure over a long time period, resulting in cancers and other generally irreversible effects (3). The largest risk of Aflatoxins (AF) to humans is usually the result of chronic dietary exposure. Such dietary AF exposures have been associated with human hepatocellular carcinomas, which may be compounded by hepatitis B virus. Approximately 250,000 deaths are caused by hepatocellular carcinomas in China and Sub-Saharan Africa annually and are attributed to risk factors such as high daily intake (1.4 μg) of AF and high incidence of hepatitis B (3).
  5. Mycotoxins have been shown to adversely affect your gut micro-biome – even at low levels (1).
  6. Experts consider mycotoxins as one of the most important food-related risks (ranked 3rd highest behind microorganisms and obesity) (15). Experts rate Mycotoxins as a higher chronic dietary risk factor than synthetic contaminants, plant toxins, food additives, or pesticide residues (7).
  7. Goods coming into EU are protected by maximum permitted levels (set by EFSA) but these assessments are extrapolated from animal studies. Some researchers also believe there is no safe “minimum limit” for Aflatoxin B1 - the most potent natural carcinogen (13). One early paper published by EFSA had no objection to increasing the level of total aflatoxins for almonds, hazelnuts and pistachios from 4 to 8 µg/kg (11), yet a later paper raised concerns about increasing the level for peanuts from 4 to 10 µg/kg saying it would increase cancer risk by a factor of 1.6-1.8 (10). Clearly the science is constantly changing but one other explanation may be that pressures are bought to bear by various lobby groups trying to increase trade revenues? The interests of producing countries do not necessarily coincide with those of recipient countries and the presence of mycotoxins in food commodities could lead to trade barriers, unless all parties agree on the approach for deriving safe levels and can see that their own interests have been addressed (14).
  8. In 2013, EFSA (2014a) reported that France even requested a temporary derogation to the maximum levels of mycotoxins in maize and maize products. It did so because French 2013 occurrence data of certain mycotoxins in harvested maize significantly increased. According to EFSA (2014a), this has contributed to a situation, where some consumer groups faced an exposure close to what is considered an unsafe level. France seems to be slightly more vulnerable to some mycotoxins (15).
  9. There is much about mycotoxins that society does not yet know, such as how toxic they are at very low levels. Unlike bacterial toxins, fungal toxins are not proteins and therefore barely detectable by the immune systems of humans and animals (15).

How widespread are Mycotoxins?

  1. Some estimates put the % of worldwide crops infected by mycotoxins at 25% (1, 3, 6, 13). A global monitoring project lasting more than ten years analyzed over 70,000 samples of primary crop products and concluded that 72 percent of all samples contained at least one mycotoxin, and almost 40 percent of samples were co-contaminated with two or more mycotoxins (15).
  2. In Yugoslavia, studies indicated that 91% of raw milk samples tested were contaminated. In the USA, a study was conducted in seven Midwestern states in 1988–1989 and found mycotoxins in 19.5% of corn samples assayed prior to any induced environmental stress and 24.7% of the samples following stress induction. India is a prime example of a country in which the economy is affected heavily by mycotoxins. In a study in the Bihar region from 1985 to 1987 nearly 51% of the 387 samples tested were contaminated with molds. Of the 139 samples containing AF, 133 had levels above 20 μg/kg. In another study levels as high as 3700 μg/kg (!!) of AF was reported in groundnut meal used for dairy cattle. Researchers also found 21 of 28 dairy feed samples from farms in and around Ludhiana and Punjab to be contaminated with AFB1 at levels ranging from 50 to 400 μg/kg (3).
  3. A changing climate has a direct impact on mycotoxin production. Mycotoxins are among the major foodborne risks that are most susceptible to climatic change. Predictions have suggested fungal pathogens across the globe are migrating at 5 to 6 km per year on average from the equator towards the poles (15). Some areas who never had issues before (like Serbia and Hungary) are now reporting crops infected with Mycotoxins. Prolonged hot and dry weather in the year 2012 in Serbia resulted in 69% of maize contaminated with Aflatoxins (1).
  4. Changing farm practices are also having an adverse impact e.g. changes include fewer break crops, a move from ploughing towards minimum tillage systems, and an increase in the area of mycotoxin-susceptible crops such as maize. This has led to fewer opportunities to “clean” fields between crops, fewer opportunities to bury fungal spores after harvest, and a gradual increase in mycotoxin build-up (15).
  5. Global food industry since WW2 has spread mycotoxins far and wide and the growth in some cancers since WW2 has been speculated to be caused by increased exposure to mycotoxins since WW2 (12).
  6. Mycotoxins pose an important danger to human and animal health, albeit one that is hard to pin down. The incidence of mycotoxicoses may be more common than suspected. It is easy to attribute the symptoms of acute mycotoxin poisoning to other causes (3). Most illnesses caused by mycotoxins are not referred to a doctor. Those that do lead to a medical appointment, are often either not identified as mycotoxin related or officially recorded as such. In other words, these cases might be noticed by the individual but not identified as what caused it or collected as a statistic. Mycotoxin illnesses are therefore woefully under-reported on a global scale (15).
  7. Enhanced awareness about mycotoxins-caused illnesses is reflected by the growing number of countries that have adopted regulations, and whose number has increased from 33 in 1981 to 100 in 2003 (6).
  8. Following the link https://haccpeuropa.wordpress.com/tag/mycotoxins/, proves that product recalls due to excessive mycotoxin concentrations are more and more often reported. Accordingly, it may be stated that in 2014 alone, several products were recalled (15)

What foods are affected by Mycotoxins?

  1. Human intake of mycotoxins occurs mainly from plant-based foods and from animal-derived foods such as milk and milk products and certain fermented meat-based products (13).
  2. Ochratoxin A has been found in barley, oats, rye, wheat, coffee beans, and other plant products, with barley having a particularly high likelihood of contamination. Ochratoxin may be present in certain wines and has been detected in blood and other animal tissues and in milk, including human milk! It is also frequently found in pork intended for human consumption (7). Other products of concern are beans, cocoa, malt and beer, bread and bakery products, wines and grape juices, spices, poultry meat and kidneys, pig kidneys and pork sausages (3). Contamination of food commodities, such as cereals and cereal products, coffee beans, dry vine fruits, wine and grape juice, spices and liquorice, occurs worldwide (2).
  3. Aflatoxins are produced by certain molds (Aspergillus flavus and Aspergillus parasiticus) which grow in soil, decaying vegetation, hay, and grains. Crops that are frequently affected by Aspergillus spp. include cereals (corn, sorghum, wheat and rice), oilseeds (soybean, peanut, sunflower and cotton seeds), spices (chili peppers, black pepper, coriander, turmeric and ginger), and tree nuts (pistachio, almond, walnut, coconut and Brazil nut). The toxins can also be found in the milk of animals that are fed contaminated feed, in the converted form of aflatoxin M1 (2). Aflatoxins have also been found in low levels in coffee, and have also been found in contaminated tobacco leaves (12).
  4. Finally, it should be mentioned that Aspergillus oryzae and Aspergillus sojae, species that are widely used in Asian food fermentations such as soy sauce, miso, and sake, are closely related to the aflatoxigenic species A. flavus and A. parasiticus. Although these food fungi have never been shown to produce aflatoxin, they contain homologues of several aflatoxin biosynthesis pathway genes. Deletions and other genetic defects have led to silencing of the aflatoxin pathway in both A. oryzae and A. sojae (3).

Do Mycotoxins affect Performance/Cognitive Function & Focus?

  1. Ochratoxin A has been shown via scientific studies to inhibit mitochondrial ATP production- mitochondria convert your fuel into useable energy i.e. glucose into adenosine triphosphate (ATP) which is the fuel our bodies use. (7) This would suggest that Ochratoxin A can cause fatigue or feelings of sluggishness.
  2. Dave Asprey designed a study to determine what impact, if any, Lab-Tested (mycotoxin free) beans would have compared to coffee from local coffee shops. He worked with a Stanford researcher to put together a statistically valid, uncomfortably rigorous set of 7 cognitive tests (backward spatial span, coding, sorting, color-word, finger tapping, visual matching, and three-back). 54 people took part using different combinations of butter and coffee: Lab-tested (Mycotoxin free) Coffee (black), Coffee made with beans from a local shop (black), Lab-Tested Coffee with butter, and Coffee made with beans from a local shop with butter. The results were conclusive. On six of seven measures, the lab-tested Coffee beans increased executive function compared to commonly available coffee beans sourced from multiple regions in the United States - three-back was the only cognitive test where the lab tested coffee performed slightly worse (16).
  3. Various other studies conducted on exposure to mycotoxins (via inhalation and/or damp places of habitation) have shown – “…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...The exposed groups also demonstrated depression...while a single mycotoxin may not produce any effect, a combination of mycotoxins could induce toxicity at very low levels...” (9). This same review also hinted at a link between early childhood exposure to mycotoxins and autism spectrum disorder (ASD). The study went on to say “…It is of interest that mycotoxins can stimulate mast cells…and microglia…because mast cell–microglia interactions have been implicated in neuropsychiatric disorders, especially "brain fog."… (9).
  4. Exposure to mycotoxins has demonstrated positive associations with asthma, wheezing, and bronchitis, as well as fatigue, musculoskeletal pain, headaches, anxiety, mood, cognitive impairments, and depression (9).

How can you limit the effects and/or fix your current exposure?

  1. Green Tea Extract (GTE) can be used as antioxidant to prevent damage (500mg per day – but be careful as some people are sensitive to GTE) (8).
  2. Chlorophyllin (100mg 3 times per day) to eliminate/flush mycotoxins out (8).
  3. A probiotic which generally helps restore the natural harmony of your gut microbiota coupled with its mycotoxins reducing ability could limit the effects of mycotoxins (1)
  4. Fix any mold problems in your home/dwelling by ventilation (9).
  5. Limit intake of prime foods containing mycotoxins – corn (and all related corn products), chili peppers, black pepper, peanuts and peanut butter, and milk etc. Some Hispanic populations in USA have higher levels of liver cancer (presumably caused by Mycotoxins) as they consume unusually large daily portions of corn and corn based products (7).
  6. Buy lab tested products whenever possible to know for certain your exposure (16).
  7. Buy dark roasted coffee as 40-90% of Ochratoxin A on green coffee beans can be removed via dark roasting (3).
  8. The severity of mycotoxin poisoning can also be compounded by factors such as vitamin deficiency, caloric deprivation, alcohol abuse, and infectious disease status (7). So stay as healthy as possible!

Summary/Final Words

  1. Just like one cigarette is not going to kill you – one cup of coffee with low levels of mycotoxins is equally not going to kill you. The key difference is that mycotoxins are in a wide variety of foods and it’s the chronic long term effects that can cause issues. There is no agreed safe low level of the most potent Mycotoxin – Aflatoxin B1 (the most potent natural carcinogen known).
  2. Not many studies have looked into chronic low level exposure to mycotoxins, but the few studies that have concluded that mycotoxin exposure (even at low levels) affects your gut microbiome (1) and will also impede your focus and cognitive function (9, 16).
  3. One researcher stated – “…Mycotoxins should be considered an emerging concern of which we still know precious little and so all the tools to keep them under control and at low risk to the consumer, should be used to combat them…” (15).
  4. Science experts rank Mycotoxins as one of the top 3 food related risks - way ahead of pesticides (15). Just like you may buy bottled water to avoid chlorine and/or fluoride exposure, or purchase organic vegetables to avoid pesticides – why wouldn’t you choose to drink coffee or eat foods that have been tested to have very low or no mycotoxins?


  1. Mycotoxin: Its Impact on Gut Health and Microbiota by Winnie-Pui-Pui Liew and Sabran Mohd-Redzwan - https://www.frontiersin.org/articles/10.3389/fcimb.2018.00060/full
  1. World Health organisation (WHO) Fact Sheet on Mycotoxins by World Health Oragnisation (WHO) - https://www.who.int/news-room/fact-sheets/detail/mycotoxins
  1. Impact of Mycotoxins on Humans and Animals by Mohamed E. Zain - https://www.sciencedirect.com/science/article/pii/S1319610310000827
  1. Foodborne Infections and Intoxications (Fourth Edition), 2013 by John I. Pitt -https://www.sciencedirect.com/book/9780124160415/foodborne-infections-and-intoxications
  1. Haschek and Rousseaux's Handbook of Toxicologic Pathology (Third Edition), 2013 by Wanda M. Haschek, Kenneth A. Voss - https://www.sciencedirect.com/book/9780124157590/haschek-and-rousseauxs-handbook-of-toxicologic-pathology
  1. Foodborne Diseases (Third Edition), 2017 by R.A. Stein, A.E. Bulboacӑ -https://www.sciencedirect.com/book/9780123850072/foodborne-diseases
  1. Mycotoxins by J. W. Bennett, and M. Klich - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC164220/
  1. Mycotoxins and human disease: a largely ignored global health issue by Christopher P. Wild, Yun Yun Gong - https://academic.oup.com/carcin/article/31/1/71/2392129
  1. Effects of Mycotoxins on Neuropsychiatric Symptoms and Immune Processes by Aarane M. Ratnaseelan, Irene Tsilioni, Theoharis C. Theoharides -https://www.clinicaltherapeutics.com/article/S0149-2918(18)30229-7/pdf
  1. Effect on public health of a possible increase of the maximum level for ‘aflatoxin total’ from 4 to 10 μg/kg in peanuts and processed products thereof, intended for direct human consumption or use as an ingredient in foodstuffs by EFSA Panel on Contaminants in the Food Chain (CONTAM) -https://efsa.onlinelibrary.wiley.com/doi/10.2903/j.efsa.2018.5175
  1. Aflatoxins in food: EFSA assesses new proposed maximum levels for almonds, hazelnuts and pistachios and advises the European Commission by EFSA Panel on Contaminants in the Food Chain (CONTAM) - https://www.efsa.europa.eu/en/press/news/070302
  1. Effects of different mycotoxins on humans, cell genome and their involvement in cancer (Review) by Mowaffaq Adam Ahmed Adam, Yasser M. Tabana, Khirun Binti Musa, Doblin Anak Sandai - https://www.spandidos-publications.com/10.3892/or.2017.5424
  1. Mycotoxins by the Institute of Food Science & Technology - https://www.ifst.org/resources/information-statements/mycotoxins
  1. Approaches to the risk analysis of mycotoxins in the food supply by T. Kuiper-Goodman - http://www.fao.org/3/x2100t/x2100t03.htm
  1. Mycotoxins – The Hidden Danger in Food and Feed by The Andersons Centre & HFFA Research GmbH - https://theandersonscentre.co.uk/wp-content/uploads/2017/11/Mycotoxin_Final-280217.pdf
  1. The Bulletproof Diet by Dave Asprey (Buy from Amazon)
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