Because of the nature of indoor environments, it’s easy for surface mold to develop – especially in the bathroom area, where air circulation is at a minimum. Before addressing the surface issue, it is important to rule out the presence of a deeper problem. Sometimes surface mold is due to hidden water damage. A crack in a tile or a history of a water leak may indicate a larger problem, which can lead to serious health issues. See “Where Do I Begin?” for suggestions on ways to address hidden water damage.
If the mold appears on a wall rather than tile, be sure to check for hidden water damage and avoid surface solutions that leave behind any residual water that only add to the problem. Purchase a simple moisture meter to see if hidden moisture exists. Moisture meters are readily available at hardware stores.
Place probes in suspected wall to see if hidden moisture is present.
If you are confident that the problem is a surface one, it is best to avoid bleach. While bleach does kill bacteria, and viruses, it does not kill mold. It merely takes away the color and can trigger more problems because of its toxicity.
Similarly, ammonia is very irritating to the mucous membrane and while it may be effective on surface mold spores, it does not eradicate dead spores that contain glucans, allergenic proteins, and mycotoxins.
*Bleach and ammonia should never be mixed. The combination will generate toxic gasses called chloramines.
What can you do to eradicate surface mold?
1. Check the ventilation and reduce moisture
If the mold is in the bathroom, is the exhaust fan in good working order? Are family members regularly using the exhaust fan? A new exhaust fan can be an excellent investment if it is not working properly. A portable dehumidifier may also help provided it is maintained properly.
2. Wipe down the shower after each use
Even with the best ventilation, mold can grow naturally because of the moisture and lack of sunlight. It may seem overwhelming to wipe down the tile after every shower, but once family members are in the habit, the tile stays clean and dry.
Readily available, borax is an excellent anti-fungal agent. Create a paste with borax and water and scrub onto the area. Rinse and dry well. This may be applied several times and may be combined with tea tree oil for added effectiveness. Concerned about the potential toxicity of borax? See the article The Safety of Borax.
4. Hydrogen peroxide
Peroxide is an effective anti-microbial without the toxic fumes that come along with the use of bleach. If using 3% hydrogen peroxide, which is the dilution found in stores, just apply directly to the mold and scrub. Certified 35% food grade peroxide, available online, may also be used, but should be carefully diluted before using. A third option is 10% hydrogen peroxide, also found online. It need not be diluted and offers a stronger option. Always use caution however as anything greater than 3% may burn the skin.
5. White vinegar
White vinegar also has excellent anti-fungal properties. Consider using white vinegar in combination with any of the above. Try the borax paste and follow with several sprays of white vinegar.
6. Tea tree oil
Tea tree oil is known for its ability to kill fungus and is safe for ingestion or application to skin and hair. (See this study for more on the antifungal potency of tea tree oil.) You can easily make a tea tree oil spray by combining water with 5-10 drops of tea tree oil. Spray on the surface. You can also add tea tree oil to baking soda or borax paste.
7. Grapefruit seed extract
Derived from the seed and pulp of grapefruit, GSE has excellent anti-fungal properties. GSE can be added to white vinegar or combined with other solutions on this list. Nutribiotic offers a reputable product. Find it here.
Pumice bars are cheap and readily available in the cleaning aisle of many big box stores. Pumice is ideal for any cleaning, including surface mold. Scrub the area with pumice and follow with any of these treatments.
9. Baking soda
Baking soda or sodium bicarbonate is an effective antifungal agent by itself or in combination with other agents. Make a paste of baking soda and water and scrub. Boost the effect by making your own washing soda (sodium carbonate) by heating the baking soda. ( For more on making washing soda see DIY Washing Soda.)
10. Chitosan powder
Chitosan is derived from the chitin component of crab, shrimp, and other crustacean shells. It has noted antifungal properties. Make a paste of chitosan powder, tea tree oil and water for an adequate surface solution. Amazon offers these chitosan options.
Vodka is a potent antimicrobial and can be applied directly to surface mold. Fill a spray bottle and spritz it on the area. Allow it to sit for 10 minutes or so and scrub with a rag or pumice stick.
Products to Purchase
The following products do not contain bleach and are chemical-free. They are available from Amazon.com and other online sellers.
- EC3 Mold Solution Concentrate
- Benefect Botanical Disinfectant
- Bulletproof Homebiotic Spray (for surface mold prevention)
As with any mold issue in the home, surface mold is not to be taken lightly. Consider these non-toxic solutions and avoid chlorine bleach to help maintain a safe home environment.