In green building literature, the primary aspect of a healthy home is indoor air quality. How many times have you walked into a home and smelled a peculiar odor? Does your own home have a smell? That can be a sign of an unhealthy home.
Many people think that if they have odors in their home, the best thing to do is to use air fresheners or scented candles. (And indeed, we are pummeled with advertisements from Procter & Gamble and SC Johnson to make us think we will be happier if we spray air freshener in our home!) This actually worsens the problem. Why? Air fresheners do not actually freshen the air – they just cover up other odors and make it harder to find the source to eliminate it. Additionally, many air fresheners contain toxic ingredients that are bad for human health. The Environmental Working Group (EWG) Guide to Healthy Living examined 277 air fresheners, and of those over 82% got a D or F in terms of high concern for causing harm, mostly in the areas of developmental and reproductive toxicity, with some concern for skin irritation and asthma/respiratory issues.
According to the EWG:
“Avoiding products with added fragrance can reduce your exposure to unnecessary chemicals. Pick products whose labels say ‘fragrance free.’ Give up air fresheners. Their sole purpose is to flood the air with fragrance that masks odors.”
Clean air has no smell at all, so that’s what to strive for.
What’s wrong with candles? Scented candles in particular are just like air fresheners, which, according to the EWG, release mixtures of undisclosed fragrance chemicals into the air to cover up other odors. Even unscented candles can be harmful to your health. Most candles on the market today are made of paraffin wax, which is a petroleum-based product manufactured as a byproduct of refining oil. So basically, you’re burning a fossil fuel in your home without venting it outside. Candles made from paraffin, when burned over time, leave black soot stains on ceilings, walls and furniture. And guess what? Those tiny black soot particles that leave stains are easily inhaled and can cause respiratory illnesses.
So, what to do about household odors? The most effective ways to limit indoor air pollutants are source control and ventilation. Tips #4-6 will look at source control by examining products and categories of products that can off-gas harmful chemicals or volatile organic compounds (VOCs) into the air. This week, though, we assume there will be indoor air pollutants no matter how hard we try to purge our home of these products—so the natural solution is to ensure good air filtration in your home. This means exchanging inside air with outside air.
First, if you have ductwork: make sure you change your air filters on a regular basis. Depending on whether you have pets and how many people live in your house, you may need to change them quarterly, if not monthly.
What you need to know: Air filters have what is called a MERV rating on a scale of 1 to 16. MERV stands for Minimum Efficiency Reporting Value, and the higher the MERV rating, the more efficient your filter is at removing particles from the air. Typical MERV filters are around 8; critical areas
of hospitals use 14. A standard 20” x 20” x 1” MERV 8 filter at Home Depot retails for $8.97 or less if you buy in volume. Higher prices usually go with ratings (the same size 3M Filtrete with a MERV 12 rating is currently $19.97 at Home Depot), so you have to weigh the value of a clean air against your budget.
(If you are building a new home, consider a heat recovery ventilator, which is an energy efficient method of obtaining air exchange with the outdoor air while reducing the cost of heating and cooling the ventilation air.)
Second, whether you have ductwork or not, you need to get some air circulation in the house for it to be healthy. That can mean ceiling fans, regular fans and opening the windows periodically. There are other “air cleaners” on the market that can be effective at removing particles, but they are not designed to remove gaseous pollutants.
One thing you might not know is that houseplants act as natural air filters that remove pollutants and keep indoor atmospheres cleaner. NASA conducted a study on this phenomenon, and not only do plants provide oxygen, they also do a good job of eliminating formaldehyde, benzene, and trichloroethylene. The top two plants in overall purifying performance are the Peace Lily and Chrysanthemum. Other top performers are mother-in-law’s tongue, English Ivy, spider plant, bamboo palm, rubber plant, and English Ivy. Additionally, plants add an aesthetic that make homes more beautiful (though that admittedly is personal judgment). However, according a U.S. Environmental Protection Agency and Consumer Product Safety Commission (CSPC) report, “there is no evidence that a reasonable number of houseplants remove significant quantities of pollutants in homes.” So, while houseplants help, they should not be the relied upon entirely for air filtration.
There are indeed other “sick home” issues which are not addressed in my Weekly Tips but are worth mentioning. These include:
- Tobacco smoke (tip: don’t smoke);
- Two odorless and colorless gases:
- Carbon monoxide, which is a lethal gas from burning fuel (tip: install a carbon monoxide detector or ensure yours is working correctly – they are required code for homes, or get a ), and
- Radon, which stems from uranium in the soil or rock on which the home is built and has been linked to lung cancer (tip: get a radon test kit if you suspect it might be in your home);
- Mold (tip: see sidebar)
SIDE BAR ON MOLD: The other major sick home issue mold, which can result from excess moisture in the home. According to Kenneth Hellevang, Ph.D.’s article Keep Your Home Healthy (North Dakota State University Extension Service, 2003):
Exposure to mold can cause cold-like symptoms, respiratory problems, nasal and sinus congestion, watery eyes, sore throat, coughing and skin irritations, and can trigger asthma attachs. Children, the elderly, pregnant women and people with existing respiratory sensitivities are at higher risk for adverse health effects of mold. If you can smell or see mold, you have a mold problem. Since people react to mold whether it is living or dead, the mold must be removed.
Mold can be removed from hard surfaces such as hard plastic, glass, metal and counter tops by scrubbing with a soap or detergent. (Do not mix ammonia and bleach. The fumes are toxic.) It is impossible to completely remove mold from porous surfaces such as paper, sheetrock (drywall), and carpet padding. Theses materials should be removed and discarded. Scrubbing may not completely remove mold growth on structural wood, such as wall studs, so it may need to be removed by sanding. Wear personal protective gear and isolate the work area from the rest of the home while sanding.
After the mold is removed from structural wood, disinfect the area using a chlorine (sodium hypochlorite) bleach and water solution. The amount of bleach recommended per gallon of water varies considerably. A clean surface requires less bleach than a dirty surface. A solution of ¼ to ½ cup per gallon of water should be adequate for clean surfaces. The surface must remain wet for about 15 minutes to allow the solution to disinfect. Provide adequate ventilation – exchanging inside air with outside air – during disinfecting, and wear rubber gloves. Rapidly dry the surfaces.
If you do not use air fresheners or deodorizers, you ventilate and filter your air, and you still notice odors, the best thing to do is figure out the source. The next three Weekly Tips will discuss common household products to help pinpoint the cause.