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Determination of Polychlorinated Biphenyl (PCB) Release Timeframe Using Weathered Congener and Homolog Fingerprints and a Multicomponent Evaporation Model

Determining the estimated timeframe of a chemical release is often important in environmental litigation. This study provides an estimate of the approximate timeframe of polychlorinated biphenyl (PCB) releases from two power transformers at an operating industrial facility where the buyer and seller disputed when the releases occurred. Wipe samples collected beneath the transformers exhibited “weathered” PCB congener fingerprints compared to the source fingerprints of the transformer oils. Comparing the observed weathered homolog pattern with modeled homolog patterns using a multicomponent liquid evaporation model, indicated the releases likely had first occurred 10 or more years prior to the sale of the facility.