EVALUATION OF 2 FIELD SCREENING-TEST KITS FOR THE DETECTION OF PCBS IN SOIL BY IMMUNOASSAY

Effective field screening methods could minimize the time and reduce t he cost of characterizing and remediating hazardous waste sites. Rigor ous evaluation of novel field screening methods is required before the y can be considered as replacements for, or adjuncts to, currently use d laboratory methods. Alternatives to standard laboratory analytical m ethods should be rapid, analyte-specific, cost-effective, accurate, an d sensitive in the range at which the analyte is regulated. In this st udy, 2 immunoassay-based field test kits for polychlorinated biphenyls (PCBs) in soil were evaluated with reference to those criteria. PCBs were analyzed in both spiked and field soil samples. Based on laborato ry performance, we estimate that 20 to 40 samples can be analyzed in t he field per day. Sensitivity of the assay is in the 1 ppm range. Beca use the assay is based on the specificity of the antigen/antibody reac tion, interferences are practically negligible. The method is accurate ; the false-negative and false-positive results that were observed can be explained by differences in the immunoreactivities of the Aroclors present in the test samples and the Aroclors used as standards in the assay. The savings in time and expense to analyze PCBs in soil with t he immunoassay-based test kits over conventional laboratory methods sh ould be substantial.