Technology Description

The demonstration includes two analytical chemistry components that are modified from standard Environmental Protection Agency (EPA) methods, but their integration and use together with innovative data analysis methods in a forensics study are novel and need validation to provide case studies for future site use. Rapid screening characterization (RSC) by SPAWAR Systems Center, San Diego (SSC-SD) of semivolatile organics can be conducted using various commercially available immunoassay test kits. The techniques for the RSC of polychlorinated biphenyls (PCB) in sediments have been adapted from methods developed for use in soils. The techniques are modifications of the current standard immunoassay methods described under EPA Method 4020 (Screening for PCBs by Immunoassay) that have been developed at SSC-SD to work on the wet, organic rich matrix found in many sediments. Battelle has in recent years developed state-of-the-art PCB analytical methods using high-resolution gas chromatography and low-resolution mass spectrometry operating in selected ion monitoring mode (HRGC/LRM-SIM), that are highly cost-effective and provide detailed, high-quality, data. The method employs components of EPA Method 680 (HRGC/LRMS PCB homologue and total PCB method) and Method 1668a (HRGC/HRMS PCB congener method). The base methods have been modified to include many nonstandard, environmentally important, and diagnostic PCB congeners that will permit data analysis for differentiating potential sources. PCB forensics data reduction and analysis include various types of statistical and other numerical analyses, including the application of sophisticated receptor modeling methods to help tease out source relationships.