Project Summary (2006-2010)

The Synthesis Core directly supports the research function of the University of Iowa SBRP research program by providing a PCB exposure mixture as well as individual PCB congeners and PCB metabolites. In support of the Analytical Core, this core provides analytical and quality control/assurance standards. In close collaboration with the Analytical Core, which is responsible for purity control of PCB congeners and testing of prepared standards against certified Standard Reference Materials, the Synthesis Core acquires or synthesizes individual PCB congeners and prepares stock solutions for use as PCB calibration mixtures. Core staff also prepare an airborne PCB exposure mixture for in vitro and in vivo studies for several research projects. This exposure mixture approximates the PCB congener profile of the mean Chicago PCB signal. The mixture is prepared in cooperation with the Analytical and Inhalation Toxicology Cores by mixing of Aroclor 1242, Aroclor 1254 and individual PCB congeners. Core staff synthesize PCB congeners to supplement the PCB exposure mixture and for use with the in vitro and in vivo studies. These PCB congeners are also available to the Analytical Core for the preparation of analytical and quality control/assurance standards. Dr. Lehmler's core team also synthesizes methoxylated and hydroxylated PCB metabolites. Both the hydroxylated and methoxylated PCB derivatives are provided to the Analytical Core and individual research projects as analytical standards for the identification and quantification of (unknown) metabolites. An additional task is the synthesis of quinoid metabolites of PCBs and their glutathione conjugates for several research projects. Finally, the core provides PCB sulfates as needed. All compounds are synthesized, if necessary in large (gram) quantities, with straightforward synthetic approaches that are well established at the University of Iowa. Drawing on their extensive experience with the synthesis of organohalogen compounds, Synthesis Core staff are able to synthesize every compound of interest to the individual research projects.