|
|
Spring 2004 Unsolved History: UM Anthropologist Delves Into Old West Mystery Freeze-Thaw Satellite: University Launches New NASA Science Mission Harnessing the Honeybee: UM Researchers Use Insects to Detect Pollution, Land Mines Mission to Mars: UM Creates Game About Reaching, Colonizing the Red Planet
|
||||
|
BIOLOGICAL SCIENCES Harnessing
the Honeybee
The honeybee zoomed intently over the grassy meadow at the U.S. Army base, ignoring the lasers pinging off its fuzzy body. Every 26 seconds the green light lanced out, marking the bee's progress using lidar, radar's more-advanced cousin. Sampling
the air with antennae that give it a bloodhound sense of smell, the
bee followed an invisible chemical plume it had been taught to associate
with food. The odor of explosives led the worker bee to a buzzing cluster
of its sisters. This time there was nothing to eat, but the flying
foragers visited the spot again and again, allowing lidar to paint
a grouping of dots on a computer screen. "That was my eureka moment," says Jerry Bromenshenk, a research professor in UM's Division of Biological Sciences. "That's when I knew I had seen a bee find a land mine." Using bees and lasers to locate mines may sound like science fiction, but that's exactly what Bromenshenk and his colleagues did last summer at Ft. Leonard Wood, Mo. The UM researchers and their partners conducted a blind field test July 25-Aug. 5 to see if bees could detect the location of explosives in a minefield. The mines were laid in a grid pattern, and each grid point might or might not have a mine buried under it. UM Assistant Professor Colin Henderson says they felt slightly uneasy working in the minefield. "The mines were deactivated," he says, "but we were told there was a 5 percent chance that if you jumped on one hard enough it would detonate." He says the bomb-sniffing bees allowed them to create a startlingly accurate minefield map, but then the bees congregated in the middle of a supposedly mine-free control area. The test continued for three days, and still many bees visited the spot away from the minefield. "At first we thought maybe the bees were really getting fooled," Henderson says. "So we brought the chemistry guy in, and he sampled the area. He found a real strong TNT, DNT and amino-product breakdown. Basically there was a mine there or lost explosive that nobody knew about. "So we found something that nobody knew was there, that nobody thought should be there, in a place where we weren't looking," he says. "That's when I said, 'Eureka!'" Bromenshenk says bees and humans have had a long and mutually beneficial history. In nearly every community and country around the world, bees are kept for the honey and wax they produce and the crops they pollinate. But for three decades Bromenshenk has worked to find another use for honeybees: that of accurate environmental sensors that detect chemical and biological particles -- including pollutants, biological warfare agents and explosives. Honeybees are busy critters, often making hundreds of thousands of foraging trips from their hive each day. Most stay within a half-mile of home, though some venture up to two miles away. Within their range, bees buzz every nook and cranny in their quest for food. Bromenshenk says honeybees are like flying dust mops because their bodies are covered with branched hairs that develop a static charge. They zoom around picking up all kinds of environmental particles and take them back to the hive. The UM entomologist first started studying bees and their hives in the mid-1970s, when energy shortages prompted a plan to build about 30 coal-fired power plants in eastern Montana and the Upper Midwest. "Nobody knew what the environmental repercussions of that kind of development would be," says Bromenshenk, who was tasked to study impacts on rangeland insects. He decided to examine bees, since they are economically valuable. "We started doing the chemistry of what showed up in the beehives," he says. "We found out we could follow the emissions from those power plants 20 to 30 miles out. With almost every other method, including direct plume samples, you couldn't follow the emissions that far. The bees were like little collecting systems -- they were very discriminating -- and this gave us the capability to look at huge areas quickly."
Bromenshenk's findings caught the attention of the Environmental Protection Agency, and soon his team was awarded grants to study whether bees could detect and map chemicals. For the next decade they used bees to sample everything from Superfund sites to urban and rural areas, and as far back as 1985 they published maps of industrial chemicals around Seattle's Puget Sound. The UM researchers prefer to use beehives already existing in an area for their research, but sometimes they rent hives and transport them to a location. Initially, a standard chemical analysis would involve washing bees or grinding them to see what they had picked up. That changed in the 1990s, when UM chemistry Professor Garon Smith developed a device to help scientists sniff the air inside beehives for volatile chemicals. The small Plexiglas instrument holds sampling tubes that filter out benign chemicals such as water or tree resins in a series of tubes, leaving the volatile chemicals to be picked up inside a few pen-sized capsules, which are taken back to the lab for analysis. Bromenshenk says this vapor-sampling system was developed while the researchers worked for the U.S. Army during the mid-1990s. They were studying hives near military landfills and urban areas, checking for trace elements of heavy metals, volatile organic materials and radioactive substances. They used the hives to check for 300 materials, with 80 that were prioritized. At one site in Maryland, Bromenshenk says, they used bees to check a military landfill site containing carcinogenic solvents and other waste. Local townspeople held regular meetings to keep tabs on the site. But the bees found the greatest health risks to the local community were often outside the fenced military compound -- coming from sources such as a big auto-repair shop, which evidently had a history of dumping out the back door, and heavy highway traffic on nearby roads. "The community members were chasing the hot spot they knew about and were blissfully unaware of the fact the real health risk was probably sitting right next door to them," Bromenshenk says. The UM researchers often take bees into potentially dangerous areas. They sampled Washington's toxic Hanford nuclear site, and at one point worked with Croatian scientists studying fallout from Russia's Chernobyl plant, as well as other sites that contained even more toxic chemicals. They needed an automated system to detect whether their bees were dying, since whatever kills bees will probably harm people. So by 1996 they had developed their first electronic beehive. UM computer specialist Robert Seccomb says, "The electronic beehive is a combination of sensors and electronics to measure just about any darn thing we want to measure inside a beehive. We have infrared detection that counts the number of bees coming and going from the hive. If it's warm and not raining, we can get over 100,000 runs out during the day, easily." During the warm months when bees are active, bee counts from an electronic beehive can be accessed at http://beekeeper.dbs.umt.edu/bees. This hive actually is located inside Bromenshenk's campus office, and a pipe lets the bees fly outside UM's Health Science building. Seccomb designed the bee-counting software, as well as the electronic beehive's artificial neural network, which automatically detects any abnormal bee behavior such as the insects not returning home. The chief architect of the most recent electronic beehive is Steve Rice, director of the electronics department at UM's College of Technology. He says their hives include a smart-hive module, which measures everything from temperature and humidity inside the hive to weather outside, as well as sampling devices that can be turned on and off. Rice says the first prototype resembled a spaghetti pile of wires and required a shed full of computer equipment to operate. Continual refinements have reduced the space needed for the equipment, "and everything could now fit in an 8- by 8- by 8-inch box." He says smart hives can be programmed to have set upper or lower limits for contaminates. When a limit is reached, the hive will automatically take a sample, sending the information back to the lab. Henderson says the team's bee technology makes hives into an inexpensive environmental monitoring system that can find everything from arsenic-polluted sediments to anthrax. He says bees can monitor a polluted area much more thoroughly and cheaply than a typical engineering firm. The electronic hives also could be used to protect agricultural bees. Bromenshenk says one of their smart beehives is like having an air sampler with a mile-wide nozzle. If there are any pollutants within a 2-mile radius, the bees will detect it. But then about five years ago, the UM group was asked by the federal Defense Advanced Research Projects Agency if bees could find the exact source location of something for which they were looking. This would
require tracking and mapping the bees, Bromenshenk says. At first they
tried attaching tiny microchips to the backs of the insects, but the
chips were too heavy. It also would be incredibly time-consuming affixing
chips to many bees. "As far as we know, there is no technology out there that has as much sensitivity as our bees for locating such things as mines or unexploded shells," Bromenshenk says. "The bees also are much safer to use, since they won't set off a mine like a human or dog would." Unexploded land mines are a major worldwide problem, and the potential for UM's bee research has garnered international attention. Bromenshenk says they have done scores of interviews with media from the National Enquirer and the Wall Street Journal to Animal Planet, the BBC and Der Spiegel. But one question remains: How do the researchers train bees to hunt for what they want found? Why would a bee hunt for land mines or toxic waste and not the nearest blossom? That, Henderson says, is a trade secret. In fact, it's one of the backbone technologies of Bee Alert Technology Inc., a University-spawned company the researchers formed to market the science they have pioneered. The fledgling firm already has earned a defense department Small Business Innovation Research grant for pilot work to study whether its business concept is sound. If it is, much larger grants could be forthcoming. "We could market smart beehives, systems for hunting land mines, every aspect for use with agriculture -- any aspect of this that has a marketable or practical use," says Bromenshenk, a third-generation Montanan. "And we would like to see this technology nurturing our state. We want to see Montana firms; we want to see Montanans as employees. "And helping protect people around the world from pollution and land mines wouldn't hurt either." -- By Cary Shimek |
Rita
Munzenrider, Director |
