Sacramento District scientist shrinks time and space to detect dangerous gas
Release no. 12-037
SACRAMENTO, Calif. – A U.S. Army Corps of Engineers Sacramento District scientist is playing a leading role in a series of research projects to protect American service members from toxic vapors, make toxic cleanup projects more effective and potentially change how the world monitors airborne chemicals.
Dr. Janis Hulla, Sacramento District senior toxicologist, is a member of a multidisciplinary team that is developing an instrument that could be worn by military fuel handlers to warn them of unsafe exposure to naphthalene – a component of petroleum fuel vapor that may be carcinogenic.
“Our current test model is in a belt pack, but we envision a much smaller device that would warn the wearer of unsafe conditions; track exposure levels over time and by location; and transmit that data wirelessly for central collection,” said Hulla. “Our goal is real-time, lab-quality data coming from a small mobile unit that includes GPS and cell phone technology.”
Old-fashioned mothballs were pure naphthalene. California declared naphthalene a human carcinogen in 2005. The U.S. Environmental Protection Agency is on the cusp of doing the same, according to a draft human health risk assessment that is currently under development.
Worldwide standards for naphthalene exposure are expected to tighten significantly in the near future, said Hulla. Today’s toxicological standards include an established short-term exposure limit (STEL) for naphthalene, but existing testing methods take at least three days to alert those who were affected.
Exposure to petroleum fuels is the single largest chemical exposure for all American service members, Hulla noted. “We want to better protect war fighters who handle fuel every day, along with all those service members who may be deployed and sleeping in tents heated with petroleum fuels,” she said.
This breakthrough research project, begun in 2006, involves a team of researchers from defense, academia and private business. At the core of the new technology is a special diode developed by Photon Systems Inc. of Covina. The diode emits energy in the deep ultra-violet portion of the spectrum, making these real-time readings possible.
Accurately measuring very low concentrations of toxic gas in real time is totally new and this naphthalene dosimeter is just the first application. Current standard methods for measuring toxic gases require a full laboratory, loads of paperwork and take weeks to produce a very basic reading for one moment in time at one location.
“This new sensing technology could one day help guide environmental cleanup projects, monitor vapor intrusion into structures, control exhaust fans for industrial sites -- the possibilities inspire me,” said Hulla.
A different version of this device might be placed underground at a contaminated site, instantly reporting changes in vapor escaping up through the soil. “Real-time readings of concentrations would be far more accurate than today’s computer modeling and time-weighted averaging,” said Hulla.
“Once this method has been independently validated by other institutions, we can move to the next phase of testing,” said Hulla. Test results are currently being examined at Temple University and the National Institute of Occupational Safety and Health. The research team also includes members from University of California-Davis and U.S. Army Research Institute for Environmental Medicine.
Funding for this project comes from the Office of the Secretary of Defense, U.S. Army, National Science Foundation and NIOSH.
If this real-time monitoring technology is proven valid, worldwide public policy on how we monitor airborne chemicals could very well change. “We’re leading the world in this field of research,” said Hulla.
corps of engineers