46I-1 |
Measurement of PCBs in fish tissue using GC and ELISA |
J. A. LASRADO1, C. R. Santerre1, D. C. Deardorff2, J. R. Stahl3, and T. Noltemeyer4. (1) Foods and Nutrition, Purdue University, 1264 Stone hall, West Lafayette, IN 47906, (2) Strategic Diagnostic Inc., King of Prussia, PA 19406, (3) Indiana Department of Environmental Management, 100 N. Senate Ave., P.O. Box 6015, IN 46206, (4) EN CHEM Inc., 525 Science Drive, Madison, WI 53711 In 2000, 38 states issued fish consumption advisories for polychlorinated biphenyls (PCBs). The current methods for the analysis of PCBs uses a gas chromatograph with an electron capture detector (GC/ECD) or a mass spectrophotometer (GC/MS). Such procedures are elaborate, expensive ($400/assay), generate excessive solvent waste (4L of solvent/assay) and are time-consuming. The objective was to compare a commercial enzyme-linked immunosorbent assay (ELISA) kit to a standard method using a GC/ECD for the analysis of PCBs in fish tissue collected from a state-monitoring program. The fish tissue samples were collected during 2000-2001 during an Indiana fish survey. The samples that contained PCBs in the range of 0.05 to 0.5 ppm as determined by the GC/ECD, were analyzed with ELISA. Species included in the analysis were Carp, Channel catfish, Largemouth bass, Freshwater drum and Emerald shiner. For analysis by GC/ECD, fish tissue (20 g) was homogenized and extracted by the Soxhlet’s method. The PCB in the extract was separated from the lipid and cleaned up using a florosil column. The extract was concentrated and analyzed. For analysis by ELISA, fish tissue (1 g) was homogenized and extracted with hexane then passed through a sulfuric acid-silica gel column. The analyte was exchanged into methanol and analyzed. The ELISA was standardized in the range of 0.05 to 0.5 ppm using Aroclor 1254 (correlation 0.95 and 0.90). Fish tissue samples (n=45) analyzed by GC/ECD and ELISA were not found to be significantly different (p<0.05). The mean concentration for PCBs using the GC/ECD and ELISA methods were 198.5 and 184.1, respectively. Soxhlet extracts were also analyzed by ELISA. The results obtained indicate that ELISA is as precise as the GC/ECD method for the detection of PCBs in fish tissue. The advantages of ELISA are that it is faster, economical and produces less waste. Reduced cost would increase number of samples to be analyzed, thus improving fish consumption advisories and protecting consumer health.
Session 46I, Toxicology & Safety Evaluation
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