Tech Note: Detecting Fecal Contamination

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CURWOOD: Just ahead, Native Americans try the corporate model in Hoonah, Alaska. First, this Environmental Technology Note from Cynthia Graber.
GRABER: Today, inspectors checking meat for fecal contamination take a low tech approach. Trained workers examine carcasses under bright lights, using only their own eyes to detect problems. Inevitably, some of those inspectors are left wondering, is that small brown spot a blood clot, or could it be a piece of manure containing E.coli bacteria? After a number of E.coli outbreaks in the early 1990s, scientists at the United States Department of Agriculture thought there had to be a more effective method to test for contamination. They knew some biological compounds glow when exposed to certain wavelengths of light. Then they thought "Cows eat a lot of plants. Plants use chlorophyll to convert sunlight to energy; so chlorophyll, a light sensitive compound, should be one of those compounds that would glow, under the right conditions." The scientists teamed up with a photochemist at Iowa State University. Together, they searched for the right wavelength to make digested chlorophyll light up. They found one: a blue light that makes even tiny spots of manure glow red. The research institutions partnered with a private firm to make machines big enough to check out entire animal carcasses. Now, they want to develop hand-held versions. The device could help prevent worker eyestrain, and make our meat safer, too. That's this week's Technology Note. I'm Cynthia Graber.
CURWOOD: And you're listening to Living on Earth.