Mold And The Bleach Myth
There are innumerable articles available online and in print on the problem of mold and how to most effectively treat it. One of the most commonly recommended mold deterrents is the use of a bleach solution. While this has proven extremely popular, the fact is that bleach as a means of combating mold simply does not work. While bleach can serve to sanitize surfaces and kill off certain strains of bacteria, it will not have any lasting effect on mold.
Right now you may be saying “But I’ve used bleach and it got rid of the mold!”. Temporarily, yes, but watch the spot over time. Bleach treatments leave behind the microflora that will allow the mold to return when the conditions are right for it to do so.
The reasoning is simple. Any type of porous surface is going to retain a measure of moisture, the water based part of the bleach solution; this will sink into the pores of the surface and allow the mold to take root and grow. Bleach treatments affect the immediate surface, however it will not penetrate into the porous area to kill off all of the mold that is present. Even the smallest amount of mold left behind can be enough to enable the infestation to grow again.
Chlorine bleach also causes long term breakdown of wood products such as studs, sheathing, plywood, OSB, and other building materials, so this cleansing process may be ultimately detrimental to the health of your home even without the mold being considered.
Still don’t believe me? Try looking for an EPA registration number for killing mold on the label of any chlorine bleach. You won’t find it, because it is not a registered EPA mold destroying product.
“While bleach is often recommended for remediation of surface mold on wood and other porous surfaces, our [university research study] study results illustrate that the treatment does not eliminate the surface microflora,“ is the conclusion of th e Oregon State University study of the effects of chlorine bleach on mold growth on Douglas fir wood [an important timber crop in the state of Oregon]. The research study was conducted by Professor Jeffrey Morrell, Dept. of Wood Science, Oregon State University, as assisted by Adam Taylor [graduate research assistant] and Camille Freitag [Senior Research Associate], as published in Forest Products Journal, 54:4, 2004.
“The use of chlorine bleach is not recommended as a routine practice during mold cleanup.” – from the www.epa.gov website.
You will also find that no professional mold remediation company utilizes any sort of bleach solution for killing mold. That alone should tell you something. So when it comes to the threat of mold in your home, leave the bleach solution alone and go with a commercially available mold treatment product (for smaller problems) or a professional mold remediation provider (for larger infestations).