Caretakers of children who are especially susceptible to air pollution (which can lead to increased risks of respiratory disease) will be able to identify locations in their everyday lives that contain high levels of particulate matter, thanks to research by an interdisciplinary team led by the University of Cincinnati and funded by the National Institutes of Health (NIH).
Sang Young Son, assistant professor in the University of Cincinnati College of Engineering, is principal investigator of the newly awarded $2 million, four-year project called ¡§Development and Field Test of a Positional Tagging Miniature Personal Sensor for PM1, sponsored by NIH's National Institute of Environmental Health Sciences (NIEHS). Son and his fellow researchers will use the grant to develop sensors for detecting and measuring particles in the air, which affect adults and children alike.
The interdisciplinary research team -- consisting of researchers at the UC colleges of Engineering and Medicine with collaborators at NASA Glenn Research Center in Cleveland, Ohio, and Washington University in St. Louis, Missouri -- plans to package condensate particulate counter sensors into miniature units utilizing microfluidics technologies that children can wear throughout the day. The team will integrate geographic information system technology developed at NASA into the sensors, allowing the exact location of specific exposures to be recorded.
Co-principal investigators consist of Da-Ren Chen, associate professor of mechanical engineering at Washington University; Paul S. Greenberg, NASA Glenn Research Center; Milind Jog, associate professor of mechanical engineering at the University of Cincinnati; Grace LeMasters, professor and director of the molecular epidemiology in Children's Environmental Health Training at UC; James Lockey, professor of environmental health and internal medicine (pulmonary) at UC; and Patrick Ryan, research associate in environmental health at UC.
Before coming to UC in October 2005, Son worked at NASA Glenn Research Center, where he developed astronaut monitoring sensor technology.
"With NASA, we are looking at a confined environment in a space shuttle,"¨ Son says. "Now we expand the application to earth." The major difference between earth and space, as far as the sensor technology goes, is the gravitational force of earth.
"Our sensor uses liquid, which reacts to the gravitational force" says Son. ¡§Therefore, we need to add the capability to control the liquid."¨
Particles in the air on the order of one micron or less have the potential to initiate inflammatory and immune responses in human lungs. Because studies indicate that the effect might be cumulative, it's important to understand more about the exposure of humans, especially children, to particulate matter in their everyday lives. Currently, understanding the potential impact of particulate matter on human health is limited by the lack of knowledge of individuals' exposures to particle size and accumulation. Current sensors with the capability of detecting particles lack portability.
Until now, that is -- the sensors that the team is developing will be approximately the size of a deck of playing cards and fully wearable by the smallest earthling. With this portability comes the capability of monitoring individuals in remote locations, like playgrounds.
Lockey says, "The availability of this miniature sensor will greatly improve the capacity to identify the type and amount of environmental exposure that can result in a disease state."
"This will help correct the frequent misclassification to various environmental exposures that can occur in human studies," LeMasters adds.
The difference between the older technology and this new development is similar to the difference between a cell phone and a landline: one goes with the person; the other ties the person to a certain location.
"We can monitor every location, every individual," says Son.
Another major difference besides gravity is the size of the individual, as air particle densities vary with distance from the ground. "There's a distinct particle difference by height," Son notes.
During the first year of the grant, Washington University will be developing a device to cut test particles down to nano sizes with which the team will test the sensor. To be able to measure the sensor's performance accurately, the researchers will need standard size particles. The second step of the grant is developing a condensation mechanism, where the air particles are condensed and collected. This is Son's role. The third phase will be to develop an optical detection module to measure the particles that are collected in the sensor. Finally, they put the components of the system and test it. It is only after the second year that the exact shape of the sensor will have been derived. In the third year of the grant, the system will be calibrated and enhanced. Field testing will take place in the fourth year.
Once the wearable sensor technology has been successfully demonstrated, field tests will be with 8-year-old children participating in the University of Cincinnati Department of Environmental Health Cincinnati Childhood Allergy and Air Pollution Study (CCAAPS). Data generated by these field tests will help the researchers identify areas where the children are exposed to the highest concentrations of particulates.
Professor Son is very pleased to receive this major award in only his second year at the University of Cincinnati. Says Son, "The experience I gained working at NASA helped me to understand how the federal agencies work. The experience I gained working at Samsung Corporation helped me understand how to link research to product development. I drew upon that experience in proposing this work to NIH."