Heavy metals and pesticides are two kinds of contaminants that can make their way into the environment, especially aquatic systems, and have been shown to adversely affect an organism's physiology. It is important to determine whether there is a presence of these kinds of contaminants in local waterways and what kinds of effects they are having on the physiology of local organisms. Metallothioneins are a class of proteins that can sequester heavy metals in the cell in order to protect against cellular damage and are produced by many organisms. This study focuses on the use of signal crayfish as a bioindicator of pollution, specifically characterizing how metallothionein in crayfish responds to chemical exposure in the lab and whether land use correlates to expression in the wild. Crayfish were collected from various sites along the Boise River and others were exposed to chemicals in lab. Field study data shows varying metallothionein levels among sites, suggesting possible clean and point source sites. Zinc chloride was not shown to have a significant effect on metallothionein expression in exposure study crayfish. Future studies include examining metallothionein expression in other crayfish tissues and using different chemicals similar to field contaminants to induce metallothionein expression.

Expression and Characterization of Metallothionein in Signal Crayfish (Pacifastacus Leniusculus) As A Model For Contaminant Exposure