Field Screening Method for Polychlorinated Biphenyl Compounds in Water

摘要

The U.S. Environmental Protection Agency has been exploring the complexation ofsilver ions with certain organic pollutants as part of a search for alternative low-cost, rapid, field screening, methods. The result is a rapid, easy, and inexpensive procedure for determining polychlorinated biphenyls (PCBs) in water. Based on previous testing of samples by General Electric Corporate Research and Development, a co-sponsor of this project, there was a special interest in developing a field-screening procedure of PCB aqueous extracts performed from a current soil remediation procedure in which the extractant contained 1-3% surfactant by weight to enhance solubility of PCBs. A test was developed, based on forming complexes of PCBs with silver ions, which was followed by UV irradiation to yield metallic silver. The appearance of a gray-to-brown color, depending on PCB concentration signaled the presence of PCBs. This method allows the test color to be directly compared with color charts to estimate the PCB concentration without the need for instrumentation.