Washington: Biologists have developed a sensor that employs one-celled protozoa to detect toxins in water sources.
The Woods Hole Oceanographic Institution (WHOI) biologist Scott Gallager’s revolutionary Swimming Behavioral Spectrophotometer (SBS) has been selected as a 2010 “Better World” technology by the Association of University Technology Managers, which was recently published in the association’s Better World Report.
The groundbreaking technique works by introducing protozoa into small chambers with water samples taken from municipal, industrial, or military water sources and comparing them to control samples.
Any alteration of the protozoa’s swimming mechanics is a sign that water conditions have changed and chemical or biological contaminants—pesticides, industrial chemicals, or biological warfare agents—may be present.
A camera records the protozoa’s swimming patterns, triggering software developed by Gallager and his colleagues that interprets the water’s risk. The device then relays color-coded, traffic light-type signals to the user: green (safe); yellow (check the water further for safety); red (bad or deadly—do not drink the water).
SBS’s big advantage is that it provides virtually instantaneous feedback on the water supply’s safety, Gallager says. “It’s a very rapid approach to providing a continuous monitoring for the potential presence of toxins,” he says.
Gallager hatched the plan along with former WHOI colleague Wade McGillis—now a professor at Columbia University’s Lamont-Doherty Earth Observatory—while examining the possible effects of climate change on microscopic plankton.
Their premise was that protozoa, with their unique methods of propelling themselves through water, might act as barometers of the health of their local underwater environment.