Award Date


Degree Type


Degree Name

Master of Science (MS)


Environmental Science

First Committee Member

Shawn L. Gerstenberger

Number of Pages



Faster, simpler, and more cost-effective held screening tools can increase the amount of information available concerning the location, source, and/or concentration of pollutants present in the environment. The Enzyme Inhibition Bioassay 96 (EIB 96) is one such field-screening tool; The EIB 96 is an assay that can detect the presence of organophosphate and carbamate compounds, providing scientists with valuable information to focus their future sampling efforts. The assay is based on the inhibition of the enzyme acetylcholinesterase by organophosphate and carbamate compounds. The organophosphate and carbamate compounds that were used in this project were the pesticides carbaryl, chlorpyrifos, diazinon, dichlorvos, and parathion. The pesticides chlorpyrifos, diazinon, and parathion are organophosphorothioates, which are organophosphates with a P=S bond, and when these compounds are oxidized the compounds are converted to their oxygen analogs (P=O, substitution of a sulfur with an oxygen). Thus, this project was directed at determining the optimum oxidizing agent for use in the assay and then, to determine the oxidation products for the pesticide compounds used. (Abstract shortened by UMI.).


Bioassay; Carbamate; Compounds; Detection; Enzyme; Inhibition; Optimization; Organophosphate; Study

Controlled Subject

Environmental sciences; Chemistry, Analytic; Biochemistry

File Format


File Size

3225.6 KB

Degree Grantor

University of Nevada, Las Vegas




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