Researchers have found that when the bacteria are stressed by pollution they glow less intensely. "Our idea is that its like a deep sea canary," explained Dr William Jones, head of the team developing the potential of this biosensor at the University of Maryland Biotechnology Institute, and reported in New Scientist.
"If light starts to drop, it would trigger neighbouring samplers into action." The group has screened 10 species of luminous bacteria from fish and marine mammals. One of the most promising is Photobacterium phosphoreum, isolated from a deep sea fish. Its glow drops by half when exposed to a variety of pollutants including heavy metals, pesticides, PCBs and oil based wastes. While it doesn't distinguish between pollutants, its changed response could trigger other automated sampling devices or human intervention.