News & Events
Clarkson Professor's Indoor Air Research Finds There's No Such Thing As A Clean Sweep
[A photograph for newspaper use is available at http://www.clarkson.edu/news/photos/ferro.jpg]
Spring cleaning may be a seasonal rite of passage, but you may want to think again before you dust the top of your refrigerator or vacuum under the couch.
“Certain toxic chemicals, such as lead, pesticides, polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) are routinely found in household dust,” explains Andrea Ferro, professor of civil and environmental engineering at Clarkson University and an air quality researcher. “Simple activities such as dusting and vacuuming generate or resuspend the pollutants into the air that we then breathe in.”
And while humans spend nearly 90 percent of their time indoors, scientists have only recently begun collecting information on indoor air pollution to assess possible health risks.
“For decades researchers and scientists interested in monitoring air quality and its exposure and impact on human health have been measuring and tracking down the sources of outdoor air pollution caused by certain industries or transportation emissions,” said Ferro. “Only in the past 10 years or so have we seriously started to look at the effects on air quality and human health from air pollutants inside the home or office. In most cases, we find outdoor air is a good deal cleaner than indoor air.”
Ferro’s own research interests focus on the relationships between indoor and outdoor air pollution and her research has been published in the journal, Environmental Science & Technology. She is currently conducting research on the effects of resuspended dust particles on human exposure and the length of time pollutants remain in the indoor environment. In addition to collecting air samples from households to assess concentrations of certain pollutants, including metals and PAHs in dust particles, Ferro will soon be working in an indoor air chamber at Syracuse University. In this controlled laboratory, she will study how different particles behave in an indoor environment.
“Certain particles deposit on surfaces quickly, others remain in the air for longer periods of time,” Ferro explains. “Particles also have different residence times, that is, some remain present in the indoor air environment longer before settling and being removed by cleaning or floating out an open window. The fate of an indoor air particle depends on its size and composition and the human activity indoors.”
Ferro is also looking at emission rates from human activities, including walking and vacuuming, to determine which activities resuspend the largest concentration of particles. The researchers monitor a base rate of undisturbed air and then measure the concentration caused by different activities.
This is why, according to Ferro, it is important to do some research before spraying cleaning products in your house or office. “Many pollutants don’t just evaporate. If you spray chemicals to rid your house of cockroaches, the pesticide remains in the air for a certain length of time. The chemicals may then adhere to surfaces and carpets, but they may be released into the air again when you vacuum your house or simply walk across the carpet. In addition to the risk of breathing the chemicals, touching the contaminated surfaces can lead to exposure through the skin.”
Ferro is, however, quick to point out that households “are not toxic dump sites.” Still, she adds, there are simple ways to cut down on exposure rates.
“There are so many chemicals in household products, and few are listed on the bottles so it can be difficult to avoid harmful chemicals. As consumers we need to ask for better labeling on household products so we know what we are putting into our homes. When spraying aerosol products keep the nozzle close to the area of application to avoid spreading chemicals to other areas. Also avoid human and pet traffic in the area of application until you get a chance to wash down the area with soap and water.”
“Leaving your shoes at the door will stop a lot of harmful chemicals from getting tracked into your home and you should think twice before covering your house in wall-to-wall carpeting,” Ferro added. “Always increase ventilation when performing activities like vacuuming, dusting, frying or painting that create or resuspend pollutants. Opening doors and windows or running a fan or air conditioner will increase ventilation. As a general rule, the more ventilation, the less exposure.”
Andrea Ferro joined the faculty of the Department of Civil and Environmental Engineering at Clarkson in 2003. She is also associated with the Clarkson Center for the Environment.
She received a doctoral degree in civil and environmental engineering from Stanford University in 2002. She is a member of the International Society for Exposure Analysis and the American Association for Aerosol Research (AAAR), where she served as chair of the Indoor Air working group at the AAAR 2003 Conference. Ferro has published several articles on indoor air quality and house dust and human exposure.
Much of her current research is conducted through Clarkson University’s Center for Air Resources Engineering and Science, one of the most complete and technologically advanced centers of air quality research in the world.
PHOTO CAPTION: Clarkson University Professor of Civil an Environmental Engineering Andrea Ferro with a MOUDITM cascade impactor, an instrument that separates and collects airborne particles in nine size ranges from 0.18 mm (micrometer) to 18 mm, which she uses in her research on indoor air pollution. Here, she checks the flow rate through the MOUDI using a Bios electronic flowmeter. Particle size is important in Ferro’s research because the size of a particle affects where in the respiratory tract it will deposit.