<h3>
	Overview</h3>
<p>
	In Unit 1 we introduced the students to mercury.<span>&nbsp; </span>They learned that it is toxic and they should by now have at least a rough idea of the kinds of quantities that we might expect to find in human hair and in fish.<span>&nbsp; </span>They should also have a general familiarity with the way that mercury, in its different forms, moves through the environment; more specifically they should think about how it moves through their study site and organism.</p>