Elias Greenbaum has demonstrated that algae can be used as biosensors to detect the presence of toxins and chemical warfare agents in primary source drinking water.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/37940997@N05">Oak Ridge National Laboratory</a>
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<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/oakridgelab/3574156692/">Algae used as a biosensor</a>