Biomarkers provide an early indication of the presence and/or effects of environmental contamination. These tools have the advantage of being able to characterize the mode(s) of action of a contaminant, with some biomarkers being relatively specific to a particular type of contaminant. Biomarkers can be used directly on organisms native to the environment of interest, as well as in bioassays.Acetylcholinesterase activity and feeding rate are two relevant...