Roving Robots Pick Up Anthrax Spores

In the event of a biological weapons attack, first responders might deploy legions of vacuum robots to quickly find contaminated areas. Researchers at the Environmental Protection Agency report that commercial cleaning robots, such as the Roomba, can effectively collect spores from Bacillus anthracis, the bacterium that causes anthrax (Environ. Sci. Tech., DOI: 10.1021/es4000356).

First responders typically test potentially contaminated areas by wiping hard surfaces with a sponge or collecting samples from carpet using a vacuum hose. The problem is that these tests cover only a small area at a time, not much more than a square meter. This limitation could slow cleanup and recovery after a large-scale attack, write the study’s authors, led by Sang Don Lee. They believe cleaning robots, which can roam from 100 to 400 m² on one battery charge, might prove superior spore collectors.

The researchers tested five commercially available cleaning robots. They spread roughly a million anthrax spores per square foot on the floor inside a 91-cm-wide by 91-cm-long test chamber. The chamber sat in a special room that prevented the spores from escaping into the environment. The team ran two tests: one with a carpeted chamber floor and the other with a laminated one. They also compared the robots to the two standard collection methods.

Each robot run lasted up to nine minutes. In the carpet tests, the best robot collected 62% more spores then the traditional vacuum method did. Meanwhile on the laminated floors, the best robot collected 38% fewer spores as the sponge method. So although further studies are needed, the robots show promise as a fast way to detect contaminated areas, the authors say.