Identifying and treating mould

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Many people visit Clean Cloth Nappies to learn how to remove mould from textiles. Our advice is based on peer reviewed studies, and has been extensively tested.

Moulds are important to biodiversity and can be very beneficial to humans. Penicillium is a mould that is used to produce antibiotics. Your favourite blue vein cheese also contains mould. Moulds can also be very damaging. 

The most common household moulds are Aspergillus, Penicillium and Cladosporium. These species produce white, green, olive green, brown and black colonies.

Different types of mould spores growing on a petri dish.
Mould on a petri dish (Source: Wikipedia)

Where is mould found

Moulds are everywhere, when the conditions are right, mould will grow. Mould requires moisture, oxygen and a food source to grow. Mould regrows because spores are everywhere, and on surfaces such as grout, the feet (hyphae) hook into the surface.

Is mould dangerous 

The level at which mould is a problem depends on; the type of mould, the amount of mould, where it is growing, a person’s sensitivity, any underlying health conditions and the way a person is exposed to it.

Small amounts of mould found in the shower, on clothing or on fabrics do not pose a health concern. It can easily be killed and remaining stains removed. 

Removing mould

We recommend chlorine bleach. It is a myth that chlorine bleach only removes colour from mould. At the right concentration, chlorine bleach it will kill mould and remove any remaining stains. The concentration required depends on the type and amount of mould and the type of fabric.  

Using concentrations which are too high on non colour fast fabrics will result in fading and damage, but the same concentration can be suitable for synthetic fabrics. Undiluted chlorine bleach can burn non synthetic fabrics such as white cotton, and cause permanent yellowing.

Treating mould with chlorine bleach 

Sodium hypochlorite the active ingredient in chlorine bleach, sold in the laundry aisle of the supermarket, is the only disinfectant which is able to rapidly kill common household moulds Aspergillus, Penicillium and Cladosporium on both porous and non porous surfaces. It is effective against both mould and mould spores. 

Chlorine bleach is inexpensive, readily available, environmentally friendly and suitable for textiles, plastics and items which can be submerged.

Treating mould with high heat

Ultra high heat (90/95°C front loader machine cycle) can also kill mould, but may not remove remaining stains. It is not suitable for items which can shrink, be damaged if submerged or washed, or for items with elastics and synthetic components such as PUL.

The vinegar myth

It is a common myth that acetic acid is effective at killing mould. Currently the only mould which can be partially killed by 4.2% undiluted acetic acid, is Penicillium chrysogenum. Most household moulds are Aspergillus species. More information on cleaning with vinegar. 

The clove oil myth

It is another common myth that clove or cinnamon oil are effective at killing mould. The only mould which can be partially killed by undiluted cinnamic aldehyde and/or eugenol, is Aspergillus parasiticus. 

Treating and removing mould from buildings

Widespread household mould as a result of flood, plumbing leak or significant water damage requires removal and treatment by professional mould specialists. Stachybotrys is known as ‘toxic black mould’ which can cause allergic reactions is black and has a slimy texture, rather than a fuzzy texture. Toxic black mould in household walls, carpets and internal fittings requires removal and treatment by professionals.

References and further reading
  1. L Bullerman, F Lieu and S Seier, Inhibition of growth and aflatoxin production by by cinnamon and clove oils cinnamic aldehyde and eugenol <https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-2621.1977.tb12677.x>.
  2. Department of Health South Australia, Mould in the house <https://www.sahealth.sa.gov.au/wps/wcm/connect/public+content/sa+health+internet/public+health/living+conditions+and+sanitation/household+mould/mould+in+the+house>.
  3. S Prabuseenivasan, M Jayakumar, and S Ignacimuthu, In vitro antibacterial activity of some plant essential oils <https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1693916/>.
  4. K Reynolds, S Boone, K Bright, C Gerba, Occurrence of household mold and efficacy of sodium hypochlorite disinfectant <https://pubmed.ncbi.nlm.nih.gov/23016564/>.
  5. A K Gupta, I Ahmad, R C Summerbell, Fungicidal activities of commonly used disinfectants and antifungal pharmaceutical spray preparations against clinical strains of Aspergillus and Candida species (May 30, 2023) <https://pubmed.ncbi.nlm.nih.gov/12058733/>.
  6. Senthaamarai Rogawansamy,Sharyn Gaskin, Michael Taylor and Dino Pisaniello, An Evaluation of Antifungal Agents for the Treatment of Fungal Contamination in Indoor Air Environments (May 30, 2023) <https://pubmed.ncbi.nlm.nih.gov/26042369/>.
  7. L Coulburn and W Miller, Prevalence, Risk Factors and Impacts Related to Mould-Affected Housing: An Australian Integrative Review (May 30, 2023) <https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8835129/>.
  8. E Møllera, B Andersenb, C Rodec, R Peuhkuri, Conditions for mould growth on typical interior surfaces (May 30, 2023) <https://www.researchgate.net/publication/320482345_Conditions_for_mould_growth_on_typical_interior_surfaces>.
  9. E Kuka, D Cirule, I Andersone, B Andersons, V Fridrihsone, Conditions Influencing Mould Growth for Effective Prevention of Wood Deterioration Indoors (May 30, 2023) <https://www.mdpi.com/2076-3417/12/3/975>.
  10. S Rogawansamy,S Gaskin, M Taylor, D Pisaniello, An Evaluation of Antifungal Agents for the Treatment of Fungal Contamination in Indoor Air Environments (May 30, 2023) <https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4483703/>.