We measured polychlorinated biphenyl (PCB) concentrations in two taxa of riparian spiders from nine sites in 2011 at the Ashtabula River Area of Concern. We analyzed the extracts for 122 congeners following EPA method SW846 Method 8270D using gas chromatography mass spectrometry in the selective ion monitoring (SIM) mode. All target compounds were quantified using the method of internal standards, and all results were reported in ng/g (parts per billion) wet weight. Congener concentrations were summed to arithmetically calculate totals for individual homolog groups (groups of congeners that share the same number of chlorine atoms on the biphenyl ring) and for total PCBs. The samples were also analyzed for lipid content.