Wired Fish Monitor Water Toxins

boustrophedon writes "First miners used canaries to detect bad air. Now USA Today reports that municipalities monitor water quality by monitoring fish. The Bio-Sensor is a standard rack with eight 500 ml compartments, each containing a fish and a submerged sensor to detect a microvolt level bioelectric field. 'If at least six of the eight show signs of distress [typically due to a toxic condition], the Bio-Sensor sounds an alarm. It immediately saves a sample of the water (for more detailed analysis) while it notifies the humans in charge.'"