From trash to treasure

If you purchase a common household smoke detector, it will likely contain the radioactive element americium. That americium will likely have come, by way of the Department of Energy’s Isotope Program, from Los Alamos National Laboratory.

Los Alamos is the nation’s sole supplier of americium, which forms as another radioactive element, plutonium, ages and decays. As part of its plutonium pit production mission, Los Alamos removes impurities—including americium—from aged plutonium. Rather than dispose of the americium, Los Alamos processes it for commercial applications, including not only smoke detectors but also medical research and space applications. The Lab shipped its first commercial batch in 2020 and is working to increase production.

Until 1984, americium was produced domestically at the Rocky Flats Plant in Colorado. Following the closure of Rocky Flats, the United States became entirely dependent on americium from abroad, primarily from Russia. But now, americium production at Los Alamos reduces dependence on foreign suppliers.

“Overall, resuming production of americium and mitigating dependency on sensitive countries has been beneficial to all parties involved: the U.S. nuclear complex, taxpayers, and industry,” writes Owen Summerscales, editor of the Lab’s Actinide Research Quarterly magazine. “A true win-win.”

Americium production is also a win for the environment because instead of being packaged and shipped to the Waste Isolation Pilot Plant in southern New Mexico where it would be permanently stored underground, the element is now kept out of the waste stream.

“As plutonium used in the nuclear security complex ages, the source of americium only keeps growing,” says David Kimball, a deputy group leader in the Lab’s Actinide Material Processing and Power division. “This program means we don’t have to throw that away as a waste product—more and more customers have come to us with orders.” ★