WCAS performs a variety of pesticide analyses, many of which are not performed by other labs. In addition to the methods found in the EPA manuals for air, water, and soil, FDA has published the Pesticide Analytical Manual (PAM) for residues on crops, AOAC has methods for processed foods, NIOSH and OSHA have published methods for air, and even USP has methods for pesticides in products used in drugs.

Some methods cover many individual pesticides which fit in a particular analytical class, such as organochlorine (OC) or organophosphorus (OP) pesticides. Some, such as glyphosate, require separate methods because of their unique chemical properties. Glyphosate [N-(phosphonomethyl)- glycine] is better known as the product Round-Up® made by Monsanto. It is a post-emergence herbicide which degrades rapidly in the environment. After using it to kill weeds, the area can be planted again in just a few days. Because of glyphosate's polar nature and other chemical properties, most current analytical methods use ion chromatography to separate the analyte from its matrix and interferences. Since it does not have a chromophore for detection, the column eluant after separation is mixed with hypochlorite which oxidizes glyphosate to glycine, then mixed with o-phthalaldehyde and 2-mercaptoethanol to form a fluorescent derivative of the primary amine group. In this way both glyphosate and its degradation product aminomethyl- phosphonic acid (AMPA) are detected by fluorescence to provide a very sensitive and specific analysis. This is only one example of the many pesticides which require special equipment and chemistry for determination.

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