Immunoassay Techniques in Environmental Analyses

AbstractIn the 1980s, several Program Offices of the United States Environmental Protection Agency (USEPA) investigated the use of immunoassay methods for environmental applications with limited success. Most of the problems were with method ruggedness, i.e. they worked well in clean spiked matrices, but not very well on real world samples. The situation changed significantly in January of 1992, when the Office of Solid Waste (OSW) received its first rugged immunoassay method (for pentachlorophenol (PCP)) that worked on field samples. Several more followed, and through the early and mid‐1990s, the USEPA initiated use of immunoassay methodology in its hazardous waste program. The first group of methods incorporated into the OSW's methods compendium, Test Methods for Evaluating Solid Waste, or SW‐846, between 1993 and 1995 were a group of 10 enzyme‐linked immunosorbent assay (ELISA)‐based screening methods for various environmental analyte classes. These methods were officially ‘approved’ by the USEPA in July, 1997. We provided a great deal of training on these methods to raise the comfort level of the environmental community for their use.This chapter addresses several major topics including an overview of the USEPA's major Regulatory Programs; how analytical methods are used in Regulatory Programs; general guidelines for the development of screening methods; specific validation criteria for immunoassay methods; the current status of the USEPA immunoassay method development program; current and potential environmental applications for immunoassay technology; barriers to implementation of immunoassay methods and the steps being taken to overcome them; and future directions and new developments in immunoassay technology for regulatory programs.The overall future of the technology for environmental monitoring and analysis looks very bright. It offers a cost effective way to generate reliable information upon which to base sound environmental decisions.