Project Summary (2005-2010)

The overall objective of this project is the development, validation and implementation of rapid immunochemical-based methods for the analysis of hazardous materials and their breakdown products as biomarkers of human exposure. To understand the impact of chemical exposures on human populations, environmental levels as well as the internal doses of the chemicals must be quantified. Studies that link exposure to effect require analysis of large numbers of samples in a variety of matrices (i.e. soil, sediment, water, air, urine, blood). Immunoassays have a demonstrated reputation in the clinical arena for their sensitivity, speed, and cost effectiveness. These advantages make them ideal for measuring urinary metabolites as biomarkers of exposure. In addition, the technique has been applied to environmental analysis. One project goal is to complete the assay development of metabolites of pyrethroid insecticides. The library of assays is being validated and then implemented using urine samples from an exposed population. Another goal is to develop new compound and class-selective assays for both biomarker and environmental analysis. The compounds selected are the hazardous compounds polybrominated diphenyl ethers, acrylamide, and noncoplanar poly chlorinated biphenyls, the insecticide fipronil and the emerging pollutant antibiotic ciprofloxacin. This compound list reflects pressing environmental/human health problems as well as the needs of other Superfund projects within the Program. The assays are being formatted for rapid laboratory analysis in single and multianalyte arrays and for field use. Considerable effort is being placed on improving assay technology. One approach is to improve sensitivity by eliminating matrix effects. Toward this end a variety of extractions and cleanup methods are being evaluated (i.e. immunoaffmity, solid phase microextraction, microwave-assisted extraction) for ease of interface with immunoassays, improvements to sensitivity, robustness and speed of analysis. Advancing the technologies associated with immunodiagnostics and application to and development of new biosensor designs is also a goal. Improvements to enzymes used as labels and to enzyme substrates as well as development of novel fluorophores as labels are small steps that are being applied ultimately to the development of high-throughput biosensors.