Detection of pesticides and pesticide metabolites using the cross reactivity of enzyme immunoassays

Enzyme immunoassay is an important environmental analysis method that may b e used to identify many pesticide analytes in water samples. Because of sim ilarities in chemical structure between various members of a pesticide clas s, there often may be an unwanted response that is characterized by a perce ntage of cross reactivity, Also, there may be cross reactivity caused by de gradation products of the target analyte that may be present in the sample. In this paper, the concept of cross reactivity caused by degradation produ cts or by nontarget analytes is explored as a tool for identification of me tabolites or structurally similar compounds not previously known to be pres ent in water samples. Two examples are examined in this paper from various water quality studies. They are alachlor and its metabolite, alachlor ethan e sulfonic acid, and atrazine and its class members, prometryn and propazin e, A method for using cross reactivity for the detection of these compounds is explained in this paper.