Mycotoxins
Some species of mold produce toxins known as mycotoxins (myco means fungal). The role of mycotoxins is to help the mold colony survive by acting as a biological weapon against other competing organisms.
Toxic molds release a number of different mycotoxins which are toxic to humans such as trichothecene mycotoxins and aflatoxin mycotoxins. The mycotoxins produced by toxic molds are some of the most toxic substances we know of.
Toxic molds do not always release large quantities of mycotoxins but instead produce them only under certain circumstances. Exactly what causes a toxic mold colony to produce mycotoxins is unknown but some factors seems to be related to stress and climate conditions.
Mycotoxins are found on the spores of toxic mold and throughout all parts of the colony.
Mycotoxin Groups
Some of the different mycotoxin families are:
- Aflatoxins - includes Aflatoxin B1, B2, G1, G2, M1 and M2
- Ochratoxin - includes Ochratoxin A, B, and C
- Trichothecene - includes Satratoxin-H, Vomitoxin and T-2 mycotoxins
- Fumonisins - includes Fumonisin B1 and B2
- Zearalenone
Killing Mycotoxins
Bleach with 5% sodium hypochlorite will kill trichothecene mycotoxins as well as other mycotoxins including aflatoxin.
Fire at 500 degrees fahrenheit (260 degrees celsius) for half an hour or fire at 900 degrees fahrenheit (482 degrees celsius) for 10 minutes will also break down trichothecene mycotoxins.
It is proposed that ozone can also kill most or all mycotoxins. However the level of ozone needed to kill mycotoxins is not safe for humans so if an ozone generator is used there must be no one in the house.
HEPA air filters are not effective at removing mycotoxins but activated carbon filters can remove mycotoxins from the air.
Given time, mycotoxins do eventually break down and lose their toxicity. However some types of mycotoxins can take several years such as trichothecene mycotoxins which are some of the most stable mycotoxins.
Note that mycotoxins are not actually alive such as mold or mold spores are, so in this case killing mycotoxins refers to killing the toxicity of mycotoxins so they become non-viable, ie denaturing, breaking down, neutralising, deactivating or detoxifying mycotoxins.
How Small are Mycotoxins?
Both mycotoxins and spores are too small for us to see without a microscope. Mycotoxins are as small as 0.1 microns in size and mold spores are between 1 and 20 microns. By comparison, human hair is about 100 microns thick.
How do Mycotoxins Enter the Human Body?
Airborne mycotoxins enter into a person's body through their breathing, passing into the airways and then into the lungs. Mycotoxins also enter through a person's eyes and can be absorbed in through the skin.
Mycotoxins can also be ingested into the body. In 2004 in Kenya, 125 people died after eating maize that was contaminated with the mycotoxin aflatoxin. There have been several occasions where pets have died from eating pet food contaminated with mycotoxins too. Because mycotoxins such as trichothecene remain toxic even after cooking, mycotoxins are a big problem in agriculture with crops such as grain needing to be treated with a binding agent after harvest to remove mycotoxins.
How Long do Mycotoxins Last or Remain Toxic?
Experts claim that trichothecenes, which are probably the most stable group of mycotoxins, may remain toxic for several years. Exposure to ultraviolet light or harsh environmental conditions such as freezing has little effect on trichothecene mycotoxins.
According to Stephen Vesper of the Environmental Protection Agency: "The trichothecene toxins are very stable. Again the environment matters, if stored dry, there is little loss of activity for a year."
Mycotoxin Treatment & Decontamination
Bioterrorism experts advise that a person exposed to mycotoxins should shower for a long period of time, washing themself thoroughly with soap and water. The person should also shampoo their hair as often as possible since hair can hold a large amount of mycotoxins. Ideally the person should cut their hair, the shorter the better.
Of course before you do these things you need to remove yourself from the environment where you were exposed to mycotoxins (eg. move from the house where toxic black mold is growing) and not return unless the problem has been remediated.
What are Safe Levels of Mycotoxins?
In the United States the government has not yet set maximum levels for mycotoxins in the air of buildings, however some European countries have set limits.
Also the health issues that mold and toxic molds can cause are not yet officially recognised everywhere medically and many doctors are unaware of the symptoms mold can cause. However the Environmental Protection Agency has acknowledged that mold growing in homes is harmful to humans and that it should be removed.
Removing Mycotoxins from Carpet
Most mycotoxins from toxic mold in houses usually end up embedded in the carpet. When you walk on the carpet you stir up many of the mycotoxin particles into the air, along with other spores and allergens. There is no way to remove all mycotoxins from carpet and the only option is for the carpet to be removed and replaced.
Vacuuming the carpet, even with a HEPA filtered vacuum, will not suck up all of the mycotoxins embedded in the carpet. And even though HEPA vacuum cleaners can trap mold spores, the smaller mycotoxins will pass through the vacuum cleaner and out the exhaust, increasing the amount of mycotoxins in the air and hence worsening your toxic reaction.
Central vacuuming systems may help to remove some mycotoxins if the air from the vacuum is exhausted outside the home, but again it will still not be able to pick up all the mycotoxins embedded in the carpet.