Greening Indoor Air

by Maryann Donovan, MPH, PhD.
Researchers have reported that in the United States, the average person, both young and old, spends 85% or more of their time indoors and most of that time (60-70%) is spent indoors at home. How do we know that air contaminants in your home affect your health? A recent study conducted in New York City provides a good example. Scientists showed that pesticides that were used and stored in homes could be detected both in the blood of pregnant women and in the air of their homes. Could the scientists show a relationship between pesticide exposure and health effects? Yes! Previous studies by this same group reported that when chlorpyrifos, an insecticide, was detected in the umbilical cord blood at birth there was a significant association between high levels of insecticide and low birth weight and small size.
Our homes, especially homes that have been built in the last 35 years, are much more air tight and contain many new building products compared with homes that were built 80 or more years ago. Although some of the recent innovation has been beneficial, other developments may be contributing to poor indoor air quality. Air quality is very important because the average person takes from 12-18 breaths/minute moving a large volume of air through their lungs. When the concentration of pollutants in the home increases, exposure to airborne contaminants can become an important source of exposure to toxic pollutants. What are the possible sources of exposure and what can we do?
The American Lung Association has developed a very useful website to help you determine if there is evidence that your home has unhealthy air. On one page, they have a checklist to alert you to some common sources of household pollution and some common health effects that might suggest that the exposures are affecting household members. The Center for Environmental Oncology of University of Pittsburgh Cancer Institute also has important information to help you become aware of sources of toxic exposure, health effects, and strategies to reduce risk.
Smoking, car exhaust and chemicals stored in attached garages all contribute to indoor air pollution. Radon seeping through cracks in the house foundation is of serious concern because it is the second leading cause of lung cancer. Bacteria and mold can grow in wet areas and containers like walls, basements, ceilings roofs, and dropped ceilings; and humidifiers and de-humidifiers that store water. Combustion products from space heaters and gas and log-burning fireplaces also contribute toxins to the indoor air that we breathe. Additionally, furniture made with pressed wood and toxic glues can release solvents like formaldehyde into the air.
The chemicals that we use in our arts and crafts projects (like oil paints), to clean our homes (including air fresheners), and to control insect pests and weeds can all affect air quality. Even our dogs and cats can cause asthma if family members are allergic to fur and dander. These allergins, toxins, bacteria, and molds can trigger a wide-range of health problems including asthma, allergies, chronic illness, and even cancer.
Importantly, there are some simple changes that we can make to reduce the level of pollutants in our homes. We can change our cleaning routine by reducing or eliminating toxic cleaning products and substituting safer, effective alternatives such as vinegar, baking soda, and fragrance-free vegetable-based liquid soaps. Change the water in humidifiers and de-humidifiers frequently and keep the containers clean and free from mold and bacteria. Open windows in basements, use a dehumidi- fier, and seal cracks to control humidity and prevent radon levels from increasing. Have your home tested for radon and, if the levels are high, repair cracks and install ventilation systems to reduce radon gas to safe levels. When working with products that contain volatile organic chemicals (VOCs), such as paint, make sure that there is cross ventilation and plenty of air exchange. Although water-based paints have fewer toxic chemicals these days, they still contain VOCs and these chemicals are what you smell while you paint and continue to smell for days after as the paint dries. Nowadays, many manufacturers offer low VOC paint, and some even make paint without VOCs. Remember, if you can smell the chemicals, then that is a good indication that you need to increase the airflow in your home by opening a window and, if possible, turning on a fan.
Finally, try to avoid using chemicals that have warning labels including auto products, pesticides, yard chemicals, home cleaning chemicals, air fresheners, bleach and home care products whenever possible. Take the time to look for a less toxic alternative; these days there are many less toxic and nontoxic options. Keep your home dust-free to eliminate allergens. Solid flooring – hardwood and tiles, for instance – is much easier to keep clean, while rugs can trap dirt, bacteria, and mold. To remove allergens, use a vacuum with a high efficiency (hepa) filter, keep surfaces dusted, and wash bed sheets and blankets frequently. Instead of tracking dust and germs in from the outdoors, leave your shoes at the door. Indoor air quality will be improved if you increase ventilation, reduce toxic chemical use, reduce household dust, and keep moisture under control.


Maryann Donovan, MPH, PhD is Scientific Director, CEO of UPCI; Associate Director, Research Services, UPCI; Assistant Professor, Department of Pathology, University of Pittsburgh.
Reprinted with permission from Healthy Choices, Healthy Lives, the University of Pittsburgh Cancer Institute Newsletter, Fall 2007.