Though air pollution was mentioned by Roman philosopher Seneca as early as 63 C.E., scientific study and federal legislation of indoor air quality (IAQ) is far more recent. In the early 2000s, the Environmental Protection Agency (EPA) concluded that U.S. citizens spend up to 90% of time indoors, breathing air that may be two to five times more toxic than outdoors. Pollutants commonly found in our homes have been linked to illnesses such as childhood asthma, lung cancer and allergies.
Biological sources of air pollution include pet dander, dust mite particles, cockroaches, pollen, viruses and embedded mold. In allergic home-dwellers, all of these may produce cold-like symptoms. Molds produce reactions such as sneezing, sinus infections and rashes in sensitive people, and in some cases asthma attacks or lung irritation. These symptoms are triggered by inhaling or touching mold spores. Established molds can produce poisonous mycotoxins that cause serious health problems, especially for the elderly or immune-suppressed.
With the exception of mold, biological pollutants are generally easiest for a homeowner to eradicate. Washing and encasing bedding with protective materials, as well as removing excess carpeting and overstuffed furniture, reduces the effect of dust mite allergens. Pets kept out of bedrooms and conscientious cleaning controls many other pollutants. If embedded mold is found beneath wallpaper, under insulation or under flooring, a professional remedy is probably best. Mold thrives in moist environments; once mold has been removed, keeping your home and carpets dry is vital.
Radon is a colorless, odorless gas that escapes from outdoor soil into the home. Radon causes lung cancer. EPA guidelines require each state to test properties for radon within two years of a property transfer; radon testing should be a part of the purchase or lease process on your home. If you’re concerned about radon levels, you can contact your state’s testing office.
Combustion pollutants are gases emitted from furnaces, fireplaces, heaters, water heaters and wood-burning stoves. The most dangerous of these are carbon monoxide and nitrogen dioxide, both of which are colorless and odorless. High levels of carbon monoxide are fatal, and other gases can cause shortness of breath, eye, nose and throat irritation, and susceptibility to infections. Tobacco products also fall into this category, and smokers in the home put non-smokers at risk from second-hand smoke. Children are especially at risk from this pollutant, suffering from higher rates of SIDS, pneumonia, bronchitis and ear infections.
Maintain your appliances with regular professional inspections to ensure that combustion emissions are properly restricted. Install a UL-listed carbon monoxide monitor, and smoke outside or not at all. If you must use a wood-burning stove, use one that was built after 1990 and EPA-certified. The easiest thing to do to combat combustion pollutants is to increase the ventilation in your home; open windows, install attic fans, run window air-conditioning units with the vent open and use ceiling and bathroom fans.
Insulation is a particularly hazardous building material. Even for new construction, building codes exist to protect consumers from dangerous insulation emissions called volatile organic compounds (VOCs). Cellulose insulation that is made from recycled paper is treated with fire and rodent retardant chemicals and must be handled with care. Along with being carcinogenic, 80% of fiberglass insulation comes from recycled glass. This kind of insulation must be covered with an air and vapor seals. Rock wool insulation is similar to fiberglass, but the fibers are made from recycled iron and steel slag waste, and these fibers can be inhaled if a seal is not applied. All of these types of insulation further green energy by promoting recycled waste products, but each will negatively affect indoor air quality if not used properly.
While not legal in new construction since the late 1980s, asbestos can still be found in older homes in roofing, flooring and insulation materials. Asbestos is proven to cause lung cancer, scarring of the lung tissue and a cancer called mesothelioma. Any asbestos found in an older home should be covered intact with an airtight seal or removed professionally. Under no circumstances should homeowners attempt to remove asbestos.
Another common hazardous building material is formaldehyde, often used as a bonding agent in carpet, particle board, paneling and upholstery. Formaldehyde exposure can cause dizziness, dry mouth, headache, nausea, coughing and rashes. The best way to avoid formaldehyde is to not use it. If you must, air the product out before you bring it into your home to let the fumes evaporate.
While symptoms of poor air quality can be mistaken for allergies or colds, you may have an IAQ problem if you notice the following symptoms, especially if they are alleviated when you exit the home:
More serious symptoms include sinus infections, nosebleeds, difficulty breathing, wheezing, worsening asthma and lung disease. The EPA offers a quick checklist that may clue you in on a number of household culprits.
If you believe you have an indoor pollutant, you can consult this diagnostic aid provided by the EPA and consider testing your home. In-home test kits are available and range in price from under $100 to over $1000, depending on the range of pollutants to be detected and whether a professional laboratory tests the materials. Professional consulting firms are also available, though at a higher price. There are numerous air cleaners on the market, from tabletop models to whole-house versions. The EPA warns consumers to research these carefully. However, as some air cleaners have never been shown to do a good job of removing air particles, they are not regulated by the EPA.
The root of controlling indoor air quality is source control. Restricting the flow of pollutants into the air is the best line of defense against IAQ-related illness. Moisture control and adequate ventilation follow closely, and there is often much room for improvement without seeking professional help. When it comes to major flood cleanup, asbestos removal and air duct cleaning, it is still best to hire professionals.