by: David Andrew Smith
In the first part of this article I went through a summary of some of the reasons why we seem to rely on bleach as a staple household cleaner namely it seems to clean and it smells clean, therefore it must clean. Have you ever tried to remove mould with bleach? From window frames and bathrooms? It certainly seems to remove it and they come up looking nice and clean. Sometimes after only a couple of weeks the mould is back and within a month as bad as it ever was.
Now when you look at cleaning tips bleach is often mentioned as the product of choice for removing mould. However we all know, those of us who have tried it, that, although it works in the short term we have to keep repeating the process. Why do we continue to do this? Its not the fault of the bleach, it is because it happens to be a particularly damp spot and therefore attracts and stimulates mould growth. So it is just something we have to put up with. Very few will question whether it is the fault of the bleach being ineffective in the removal process. It can’t possibly be the bleach. This is such a wonderful product that does everything its simply the design of the building.
If we look at this closely we do in fact end up having to blame the bleach as being not very good at removing mould or mildew.
Why is it not so good? Most household surfaces that attract mould growth are by their nature porous. The fungal spores disappear into these pores and germinate spreading the growth over the surface. To completely remove the mould we need to get our ‘killing’ chemical into the pores to destroy any lingering spores. The chemical nature of bleach is such that the chloride ions are actually repelled from the pore entrance so the killing power of the bleach is entirely restricted to the external surface. It leaves any mould structure and spores that are embedded in the material to live on and fight another day. Hence the reasons for their swift return to once more blacken our world! In order to destroy all the fungi within the porous material you need a fungicide that will not only kill the mould but also its spores. Fungicides can penetrate the pores do this. An added benefit is that the fungicide can remain active within the structure for some time thereby killing immediately any of those unsuspecting spores that fall out of the air into the pores. This method considerably lengthens the time interval between removing the mould and its reappearance.
Any good cleaner when confronted with mould will use a fungicide and not a proprietary cleaning agent such as bleach. Remember that next time you call the cleaners in to give your property a deep clean.
Watch out for Part 3 that will follow shortly.