The federal government Wednesday will begin releasing bacteria at Red Line MBTA stations in Cambridge and Somerville at set times to test sensors designed to detect biological agents that could be released in a terrorist attack.
The U.S. Department of Homeland Security and the Massachusetts Bay Transportation Authority said in a press release Monday that the harmless bacteria is non-infectious and the tests will be performed when the stations are closed.
The tests will begin Wednesday and will be held periodically over the next year at the Harvard and Porter Square stations in Cambridge and the Davis Square station in Somerville.
Signs will be posted in the MBTA stations one day before each scheduled test, according to the federal agency.
Biological detection sensors have been installed at the stations and the tests are being conducted in an effort to detect and minimize any impacts from an attack or accident involving hazardous biological materials in a mass transit system.
“A rapid alert from a detection system can locate and identify these materials and provide for immediate and appropriate response to protect people and contain the hazard,” stated DHS scientist Anne Hultgren in the agency's press release.
State and local health officials along with DHS and the MBTA held a public meeting in Cambridge in May to discuss the tests, and said that there was no known threat of a biological attack on subway systems in the Boston area or elsewhere, but the systems are vulnerable to such a strike.
“This detection system will be one of the first such installed in the country, and, if it proves to be effective, could serve as a model for other mass transportation venues throughout the nation and the world,” said MBTA Transit Police Chief Paul MacMillan in the joint press release Monday.
State health officials will be working with the DHS and MBTA to monitor the results of the tests. According to DHS, the bacteria that will be used is non-infectious and is approved as a food supplement. An environmental assessment of the tests planned for the MBTA stations found no significant impact on human health or the surrounding environment from the use of the testing material.