Due to heavy rains and humid conditions in the Fox Valley recently, several people have asked me about how best to clean up mildew and mold. For houses that were actually flooded last week, the best thing to do of course, is to consult professionals familiar with floodwater cleanup. In addition to professional help though, organizations like the Red-Cross and the EPA provide online cleanup information. Some examples are the Red-Cross’s “Repairing Your Flooded Home” page and the EPA’s “Flood Cleanup” page. There are PDF booklets on these pages that can be downloaded and printed, in addition to the online help.
For people who want to do minor cleanup with commonly available, effective, low-toxicity household chemicals, there are also some good online resources. These include the Washington State Department of Health‘s page called “Got Mold?”, and the Dakota County (MN)‘s page called “Green Household Cleaning Recipes”. These sites offer practical information on how to clean up mildew and mold around the house. They also have downloadable PDF booklets of their information in addition to the online help.
Whether you have professionals do your cleanup or you do it yourself, it’s good to know that there are some very low-toxicity mold-control chemicals available. During the cleanup after Hurricane Katrina struck in 2005, there was a lot of interest in borates for mold control by federal agencies and university researchers alike. Borates include substances like Borax (the laundry product) and DOT (Disodium Octoborate Tetrahydrate, an insecticide and wood decay preventative). According to the NIH, these products have very low toxicity to people:
Toxicity Summary: The inorganic borates display low acute toxicity. They are either not irritant or mild skin and eye irritants. They are not skin sensitisers, nor are they mutagenic or carcinogenic. The most sensitive endpoints of toxicity are considered to be effects on the reproductive organs, fertility in males, and developmental effects. The doses that cause these effects are far higher than any levels to which the human population could be exposed. [Hubbard SA, Sullivan FM; J Trace Elem Exptl Med 9 (4): 165-73 (1996)]
One research project looked at the borate-based products Bora-Care (made by Nisus Corp.) and Termite Prufe (made by Copper Brite Inc.) to control mold after the flood waters receded. The active ingredient in both Bora-Care and Termite Prufe is DOT (Disodium Octoborate Tetrahydrate). Both products are registered as fungicides with the EPA. The researchers found that several of the houses in the study had dramatic reductions of airborne mold after cleaning with Borate-based products.
There are other borate-based products on the market, including:
- Tim-Bor, originally made by Borax Inc, now made by Nisus Corp.
- Borathor powder made by Ensystext
- PeneTreat made by Sashco Inc.
- Bor-Ram made by Sostram Corp.
These are all borate-based products, but remember that the “inert ingredients” in the product may not be as low-toxicity as the borate. For instance, Bora-Care, Bor-Ram and Borathor Max PT (but not the Borathor powder) are part DOT and part ethylene glycol (car radiator antifreeze), which is moderately-to-very toxic to people (as in “KEEP OUT OF REACH OF CHILDREN“) and pets (and with a very attractive, sweet taste). So you’d have to be careful not to apply the liquid on surfaces that pets (or children) could lick. Also remember that several of these companies make products that look similar, but are much more toxic than the borate-based ones listed above.
If you suffered damage to your house or property from the storms last week, our hearts go out to you. If you’re cleaning up from the damage, or just doing minor mildew and mold cleanup, I hope that you find the information above helpful.
Michael