What Are Mycotoxins?
Mycotoxins are highly toxic chemical compounds produced by certain species of mould.
Invisible to the eye and scentless, they can be inhaled, ingested, or absorbed through the skin. Mycotoxins are the underlying cause of mould illness, affecting multiple body systems.
Understanding what they are—and how to reduce exposure - is essential for effective mould remediation, home safety, and long-term recovery from mould-related illness.
What Exactly Are Mycotoxins?
Key takeaway:
Mycotoxins are chemicals that moulds release as a defense mechanism to compete with other microorganisms in their environment.
Mycotoxins are microscopic, fat-soluble toxins produced by mould. They can be inhaled, ingested, or absorbed through the skin and are found in air, dust, and on surfaces—even when no visible mould is present. Because of their extreme toxicity, some have been studied as biological weapons. Mycotoxins are the cause of mould illness and a major cause of chronic health problems.
They are incredibly small, measuring about 0.1 micron, which means they can pass easily through building materials and remain in the air or dust even after visible mould has been removed. You can’t see or smell them, yet they can linger long after remediation if not properly addressed.
Because mycotoxins are lipophilic (fat-loving), they can pass through skin, cell membranes, and even the blood-brain barrier. This allows them to accumulate in fatty tissues and organs, contributing to persistent symptoms long after initial exposure.
Because they’re so small and pervasive, even hidden mould can make you sick—such as mould behind walls, under floors, or inside HVAC systems.
Common types of mycotoxins and where they come from
Key takeaway:
Different mould species produce specific types of mycotoxins—each with unique health effects.
| Mycotoxin | Produced by | Notes / Key Facts |
|---|---|---|
| Aflatoxin | Aspergillus flavus, A. parasiticus | Potent liver toxin and carcinogen |
| Chaetoglobosin A, C | Chaetomium globosum | Neurotoxic and immune-suppressive |
| Gliotoxin | Aspergillus fumigatus | Disrupts immune function; linked to chronic respiratory issues |
| Ochratoxin A | A. ochraceus, A. niger, Penicillium verrucosum, P. nordicum, P. chrysogenum | Damages kidneys and nervous system; associated with fatigue and brain fog |
| Sterigmatocystin | A. versicolor | Precursor to aflatoxin; highly carcinogenic |
| Trichothecenes (Roridin E, Verrucarin A) | Stachybotrys chartarum, Trichoderma viridae, Fusarium spp, Cephalosporium | Among the most toxic; cause severe inflammation, skin reactions, neurological effects |
| Enniatin B | Fusarium spp | Damages cell membranes and mitochondria |
| Zearalenone | Fusarium spp | Hormone-disrupting; mimics estrogen and affects fertility |
| Citrinin | Penicillium spp, Aspergillus spp, Monascus spp | Kidney toxin; often found with ochratoxin A |
Health Effects of Mycotoxins
Key takeaway:
Mycotoxins can affect almost every system in the body—especially the brain, immune system, and detox organs.
Common symptoms include:
- Fatigue and weakness
- Brain fog, poor memory, or dizziness
- Chronic sinus congestion or cough
- Headaches and migraines
- Skin rashes, eczema, and itching
- Digestive problems and food sensitivities
- Hormonal imbalance and fertility issues
- Anxiety, depression, or mood changes
Because mycotoxins are lipophilic, they tend to lodge in fatty tissues (like the brain, liver, and nerves), which can make recovery slow if detox pathways are impaired.
Why Understanding Mycotoxins Matters
Key takeaway:
Mycotoxins are the root cause of mould illness—and knowing this helps inform cleaning to prevent re-exposure.
Recognising that mould illness is driven by mycotoxins changes how we approach both treatment and remediation. Simply removing visible mould isn’t enough—you must also address the mycotoxins left behind.
Unfortunately, many mould cleaning services focus only on killing spores but ignore the residual toxins coating your home and possessions. These toxins may remain even after mould is dead.
Even if you move house, you can bring mycotoxins with you on clothes, books, and furniture—so understanding their nature is key to full recovery. How much cleaning you need to do depends on how sick you are.
Look for a remediator that uses ozone, which can destroy not only spores, but also mycotoxins. You may need to treat the whole house as mycotoxins are so tiny they can spread easily in the air.
Here are a few tips:
- If you have to enter a mouldy space, wear a full PPE suit and use the best quality mask you can find – ask your remediator where to source one in your area. You need a mask that filters out as many 0.1 micron particles as possible.
- If you haven’t used ozone, you will need to clean your possessions. Antimicrobial products are unnecessary, simply wiping your possessions is good enough in many cases, but the cloth must be thrown away afterwards, so I suggest a low tox, biodegradable brand of wipes like Water Wipes, so you don’t keep reusing the same cloth.
- Wet mop and thoroughly dry floors.
- Curtains and clothes can be washed with borax (½ cup of borax in the washing machine before putting your clothes in) or potentially treated with ozone (depending on the fabric and length of exposure).
- Carpets, duvets, cushions, pillows, soft furnishings, and soft toys are best disposed of. Get the carpet done by a professional to avoid getting re-exposed.
- Get dust mite covers for your mattresses and never open them again.
- Place anything for disposal into heavy duty bin bans, seal, and immediately remove from the house.
- If you are short of time to clean your possessions, consider renting a storage space for a few months while you slowly work through it. When packing up your possessions, place them into good quality plastic containers with well fitting lids. Ensure that you are taking measures in the storage space to avoid damp and mould (eg silica). When you bring your possessions back home, clean them before bringing them into the house.
Taking the Next Step
Key takeaway:
If you are concerned you may be experiencing symptoms of mould illness, there is support is available.
It’s completely understandable to feel worried if you’re experiencing any of the symptoms mentioned above. Mould illness is complex, but there are practical steps you can take to identify exposure, support your body, and begin recovery.
If you want to learn more, you can download our free ebook Is Mould Making You Unwell?, or contact us directly and we’ll help you get the help you need.
