Final Decision to Certify Hazardous Waste Environmental Technology
PCB RISc™ Soil Test System (Monoclonal Test)
Certification No: 94-01-004
The technology is a fast, immunoassay-based, semiquantitative field measurement of polychlorinated biphenyls (PCBs as Aroclors) in soil. The antibody is supplied in a form bound to the walls of polystyrene test tubes. The reaction is performed on an extract prepared by dispersing and shaking a weighed 10-gram sample of soil in a small volume of methanol. A color reaction shows whether the sample extract is equal to, above, or below a chosen target level. The minimum target level (detection limit) is 1 ppm for Aroclor 1248 and 0.4 ppm for Aroclors 1254 and 1260; it is higher for other Aroclors. Through dilution of the methanol extract, the user can adapt the technique to higher target levels. The method is configured to reduce the probability of false negative results (<5% at 0.4 ppm, <1% at 1 ppm) while the probability of false positive results at the chosen target level is correspondingly increased (to 5% at 1 ppm, all for Aroclor 1248). The quantification of unknown and weathered Aroclor mixtures requires comparison of results with those obtained by a laboratory method. Both high moisture content and significant oil contamination of soils interfere with the method. The nature of the reagents requires the user to avoid temperature extremes during transport and use. Although the method has been tested for a number of possible interferences; results should be confirmed by an approved laboratory method (U.S. EPA SW- 846 Methods 8080 or 8081). The assay itself is included in U.S. EPA Publication SW-846 as Draft Method 4020 and is listed by the U.S. Department of Energy as Method OS020.
Recommended use of this type of assay is in preliminary site investigations where compelling historical data indicate the use of PCBs. In site investigations, the assays allow users to improve the mapping of PCB-polluted areas by a judicious combination of assay results with laboratory results. In remedial actions, progress can be estimated through on-the-spot testing. Details of DTSC's evaluation are contained in an Evaluation Report.
A copy of the published Certification Notice may be obtained by contacting us at:
File last updated: October 9, 1996