Particulate Matter and Indoor Air Quality
We all realize that the air outside can be very unhealthy and polluted, but most people don抰 know that the indoor air quality (IAQ) of their homes can be even worse. We all want to believe that our homes provide a clean and healthy environment for our families. A growing body of research, however, is pointing to very serious health consequences from both short term and long term exposure to particulate matter. This is generated both inside the house and brought in from outside. A problem occurs when homes are sealed from the outside air to increase heating or cooling efficiency as this allows build up of pollutants from inside the home such as Volatile Organic Compounds (VOCs), radon gas, etc. Some exchange of outside air is necessary and also inevitable no matter how well a home is sealed. So, the particulate matter found in a home's air will be a mix of particles from outside and those generated from within the home.
There are many varieties of particulate pollutants in our homes. Ones from outside include industrial sources, construction sites, combustion sources, pollen, and numerous others. Particles are also generated by all kinds of normal indoor activity ranging from cooking, walking across the carpet, your pets, or even just getting up off the sofa. Any movement or vibration can create airborne particles - even air moving over an apparently clean surface will pick up particles. Airborne allergens, mold spores, bacteria, and dust mite/insect feces are also present. A recent study by the Queensland Institute of Technology showed that even your trusty laser printer can be a high-level emitter of particulate matter. This is nowhere near a complete list of indoor particulate pollution, but what is truly disturbing is that many of these particles will lodge deep within the lung and remain there.
Radon gas has long been associated with an increased risk of lung cancer. The Radon itself is not actually that harmful, but it decays into radioactive daughter elements such as Polonium (the same element but different isotope was used to assassinate Russian dissident Litvinenko in London 2006). According to the definitive study on Radon, BEIR VI from the National Research Council, these daughter elements "are electrically charged and can attach themselves to tiny dust particles in indoor air. These dust particles can easily be inhaled into the lung and can adhere to the lining of the lung. The deposited atoms decay, or change, by emitting a type of radiation called alpha radiation, which has the potential to damage cells in the lung. Alpha radiations can disrupt DNA of these lung cells. This DNA damage has the potential to be one step in a chain of events that can lead to cancer." Using two different methods the report estimated 15,400 or 21,800 American lung cancer deaths occurred in 1995 due to exposure to Radon progeny.
If you live near a major roadway or busy street the particulate matter can be increased greatly by automobile and truck exhaust. A tremendous number of studies show a link between this particulate pollution and cardiovascular disease, respiratory disease, and cancer. Studies of adolescent children show particulate pollution can retard lung function growth similar to cigarette smoking with predictable consequences for lung health later in life. The effects come from both long term and short term exposure. Studies show in the short term mortality rates from a variety of causes rise on days with high particulate pollution. Even if you don抰 seem to be affected by high concentrations of particulates, please understand that the earliest symptoms to some long-term health problems like respiratory illnesses, or cancer don抰 appear perhaps for many years after the damaging exposure takes place.
Indoor pets, especially pets that spend part of their time outdoors can significantly contribute to poor IAQ. All furry pets shed no matter what kind they are and they also produce dander. Brushing and wiping paws before letting them inside will help. Weekly bathing will keep shedding to a minimum. Owners that permit their pets to sleep in bedrooms or on beds (where hair and dander might accumulate) will be increasing their exposure. Also, be aware that other uninvited guests in your home such as dust mites, other insects, or rodents will defecate inside. When their feces has dried up it will become dust-like and possibly airborne, circulating through your home. If this dust is inhaled it can make family members ill.
There is no simple answer to improving IAQ and there is no way to completely clean the air unless you抮e planning on living in a bubble. There are steps that can be taken to ensure you are doing everything to make your home抯 IAQ as clean as possible. One of the first things you can do is to monitor your IAQ daily and to review the output, then determine what changes can be made to improve IAQ based on the output. To find out more about our Air Quality Monitor, click on the link to the left.