You are here:
IMMUNOCHEMISTRY AT THE U.S. EPA, NATIONAL EXPOSURE RESEARCH LABORATORY'S HUMAN EXPOSURE RESEARCH BRANCH
Van Emon, J M. IMMUNOCHEMISTRY AT THE U.S. EPA, NATIONAL EXPOSURE RESEARCH LABORATORY'S HUMAN EXPOSURE RESEARCH BRANCH. Presented at EnvironAnalysis 2000, Ontario, Canada, May 9-11, 2000.
More cost-effective field screening and monitoring methods will be provided to increase the amount of information available concerning the location, source, and concentration of pollutants. Rapid and sensitive immunoassays such as enzyme-linked immunosorbent assays (ELISAs) to monitor remediation and cleanup activities at Superfund sites will be developed. Each new method will be tested on real-world samples from monitoring studies. Field studies will be conducted when time and resources permit. The feasibility and application of immunosensors to provide field analytical methods for the dynamic monitoring of hazardous substances of interest to the EPA will also be investigated. Concern has been expressed for the potential exposure of individuals to toxic compounds who live near hazardous waste sites or who may become exposed through other means. Thus, the development of methods for measuring biomarkers for human exposure assessment studies is also addressed.
During the remainder of the Task several projects will be undertaken including:
- Complete the development and evaluation of bioanalytical methods for dioxin and related compounds
- Perform dioxin immunoassay analysis on samples from a dioxin SITE demonstration
- Comparison of an ELISA with gas chromatography (GC) for monitoring polychlorinated biphenyls (PCBs) in soils/sediments collected from a Superfund field demonstration
- Survey of bioanalytical methods and sensor technologies for environmental monitoring
- Development of immunoaffinity chromatography sample preparations for PCBs
- Preparation of standard operating procedures (SOPs) for each bioanalytical method developed
- Conduct yearly research meeting
- Conduct survey of high priority chemicals at National Priorities List (NPL) sites for bioanalysis suitability
- Develop new bioanalytical methods for hazardous compounds of public concern
- Perform PCP immunoassay analysis on soil and sediment samples from a Superfund site and compare with GC data
- Preparation of fact sheets and journal articles
The HERB has developed several immunoassay methods for environmental and human exposure studies. Immunoassays to detect low levels (<10 ng/mL) chlorpyrifos in food, track-in dirt and house dust have been developed for dietary and indoor exposure surveys. An immunoassay for the urinary metabolite of chlorpyrifos, 3,5,6-trichloro-2-pyridinol (TCP) has been optimized and evaluated using real-world samples from several monitoring studies. Comparative studies with GC/MS indicate a good correlation with the TCP assay. Antibodies to detect O,O-diethyl thionates/thionothiolates have been developed and characterized for multiple organophosphorous pesticides (e.g., ethyl parathion, coumaphos, diazinon). These antibodies were characterized in several ELISAs as an approach for the class detection of organophosphorus pesticides. An immunoassay for polychlorinated biphenyls (PCBs) suitable for several soil matrices was developed for hazardous waste site monitoring and evaluated at EPA Superfund sites. The detection limits for Aroclors 1242 and 1248 in soil are 10.5 and 9 ng/g, respectively. The use of conducting polymer-based immunoassay techniques in environmental monitoring has also been investigated. Specific antibody immobilized onto conducting electroactive polymers (CEPs), in combination with a pulsed potential waveform, enables selective molecular recognition. A CEP-antibody immunosensor for PCB, had a linear dynamic range of 0.3-100 ng/mL. We have also demonstrated the use of immunoaffinity capillary electrochromatography (CEC) to perform on-line selective trace enrichment of analytes prior to capillary zone electrophoresis. These studies illustrate how immunochemical methods can respond to the needs of various monitoring programs.
The U.S. Environmental Protection Agency (U.S.EPA) through its Office of Research and Development (ORD) funded this research and approved this abstract as a basis for an oral presentation. The actual presentation has not been peer reviewed by EPA. Mention of trade names or commercial products does not constitute endorsement or recommendation for use.