In the early summer, my neighborhood experiences what we call the “yellow wind.” This onslaught is caused by thousands of acres of local pine forest releasing their pollen load in a few weeks’ time. It is not uncommon to see the edges of lakes yellow with accumulation. This accumulation also covers decks, cars and every horizontal surface in the house. We try to limit the deposits inside by closing the windows, but after nine months of winter, it is difficult to keep them closed when it’s finally nice outside.
In my previous career, I worked as an engineer/scientist for a biotechnology company. The facility I worked in was state-of-the-art and was used to manufacture pharmaceutical products. We had multiple levels of “clean rooms” in the plant and the air quality in many of these areas was typically 10 times cleaner than in a hospital operating room. Going to work in this extremely controlled environment during pollen season had my allergy-impacted eyes cleared well before lunch, and it was nice to have a few hours’ respite in my day.
These days, the clean rooms are just a memory and I work my way through the summer’s pollen with the aid of antihistamines. Pollen is just one contaminate that I now see regularly. As a carpenter, sawdust and other airborne particles are now more common. Most homeowners can add dust, mold and combustion byproducts to the list. Each of these items may have impacts on health and wellbeing for most people.
The Clean Air Act
In 1970, the Clean Air Act established the first set of National Ambient Air Quality Standards (NAAQS). The original goal was to monitor and provide regulations for a number of things that impact air quality: PM (particulate matter), ozone, sulfur oxides, nitrogen oxides, carbon monoxide and lead were items that saw initial controls. All of these items being monitored and regulated are considered outdoor contaminates; indoor air, by comparison, is virtually unregulated. Granted, it would be more difficult to have good indoor air if the outdoor air were extremely bad. But indoor air quality is often far worse than outdoor air.
John Spengler, a professor from Harvard’s School of Public Health, has done a lot of research on air quality. He states:
Modern homes are air traps
Heating and cooling a home in an economical way has led to homes being built more airtight than ever before. While this is great from an energy use standpoint, the downside is poor ventilation and poor indoor air quality.
“It has long been known that airborne particles can contribute to lung and heart disease,” says Lynn Hildemann, Ph.D., an associate professor of civil and environmental engineering and a Clayman Institute faculty research fellow.
Hildemann says, “Vacuuming the carpet, making the bed, cooking dinner or using room freshener may be hazardous to one’s health. These activities all release potentially harmful allergens and pollutants. However, household air pollution is not regulated, putting respiratory health at risk. Indoor air pollution can be up to 10 times worse than outdoor air pollution because enclosed areas allow pollutants to accumulate. Regulation of pollutants has focused on outdoor air, even though people in developed countries spend most of their time indoors.”
Hildemann continues by saying:
Indoor air quality is a worldwide issue
Hildemann recently took part in a study that looked at the effects of indoor air pollution on women in villages in southern Bangladesh. The women cook by burning debris and leaves indoors in crude, unvented clay stoves, creating dense buildups of smoke for several hours a day. Hildemann found that on a daily basis, the women breathed concentrations of airborne particles that were 15 times greater than the village men, who spend their time outdoors fishing. She also noted that respiratory illnesses among the very young were prevalent. “More young children die from respiratory illness there than from diarrheal diseases,” she says. “But parents do not associate these deaths with smoke exposure, even though the mothers keep their youngest children close by while they cook.”
Beyond the Third World
In the western world, we typically do not cook over open fires in small spaces, so most people are not exposed to this type of contamination. However, we have seen increases in asthma rates due to other issues, especially in urban children. A study by researchers at Johns Hopkins University found an association between increasing levels of indoor particulate matter pollution and the severity of asthma symptoms among children. The study, which followed a group of asthmatic children in Baltimore, Md., is among the first to examine the effects of indoor particulate matter pollution.
The study found:
“We found that substantial increases in asthma symptoms were associated both with higher indoor concentrations of fine particles and with higher indoor concentrations of coarse particles,” said Meredith C. McCormack, MD, MHS, lead author of the study and an instructor with the Johns Hopkins School of Medicine.
In many cases, the level of indoor fine particle pollution measured was twice as high as the accepted standard for outdoor pollution established by the EPA.
“Children spend nearly 80 percent of their time indoors, which makes understanding the effects of indoor air very important,” said co-author Gregory B. Diette, MD, an associate professor in the School of Medicine and co-director of the Center for Childhood Asthma in the Urban Environment.
Education is key
I often laugh at some TV commercials that are attempting to brainwash the populace with ads selling air fresheners. They claim that by spraying their product about in your home you can actually “clean the air.” Never, in over a decade working as an engineer/scientist, have I seen the addition of an aerosol into a confined environment make the air cleaner or better. These scented products merely mask the smells that people assume are indicators of “dirty air.” In the pharmaceutical plant I worked in, we had very large air handlers that used banks of HEPA filters to remove particles and air contaminates. These were costly to install and maintain and far exceed anything that could or would be installed in a typical home. But only by removing contaminates can the air become “cleaner.”
Home filters and ionic systems
Many homes have forced air heating and cooling systems; the installation of better filters may reduce the concentrations of particles and other airborne contaminates that reside in everyone’s home. But these can never reach the efficiency of real clean rooms. The air exchange rates needed for true room-sized HEPA filtration would dwarf the capacity of most household furnace or A/C components. Many have managed limited reductions through the installation of filters or secondary systems, so their use has benefit. Just do not expect them to be the end-all solution. Ionic filters or particle collectors have limited scope as well, but also can generate ozone, which ironically is an outdoor contaminate that is regulated. These devices may reduce particle counts at the cost of added ozone in the home.
Integrated approach to better indoor air quality
Perhaps the best way to control indoor air is with a combined strategy. Limiting activities that produce particles and the removal of particle-harboring materials are great places to start. Limiting the use of aerosols and venting appliances that produce contaminates to the outdoors are also some great ideas for improving indoor air quality. Using low-VOC finishes and cleaners can reduce another category of contaminates commonly found in the home.
I have completed some remodel work over the years for clients with chemical sensitivities; replacing carpet with tile and using no-VOC paints were key areas to limit some types of exposure. These strategies reduced allergen and particulate levels. When cleaning is required, the use of vacuums that have high-efficiency filters is another way to ensure that particles are indeed collected and not just redistributed in the home. Behavioral changes can also provide for a cleaner home. I have noticed that when I close the windows in the early summer, at least on windy days, the pollen piles in my house are much smaller. The world is a dusty place, as are our homes. Some simple tips can keep most of it under control.