Determination of non-ortho polychlorinated biphenyls in environmental Standard Reference Materials

The concentrations of three non-ortho ("coplanar") polychlorinated biphenyl s, 3,3',4,4'-tetrachlorobiphenyl (IUPAC PCB 77), 3,3',4,4',5-pentachlorobip henyl (IUPAC PCB 126), and 3,3',4,4',5,5'-hexachlorobiphenyl (IUPAC PCB 169 ), were determined in five NIST Standard Reference Materials (SRMs) of envi ronmental and biological interest. The measured levels were approximately b etween (0.2 to 1.3) ng/g in SRM 1588 a (Organics in Cod Liver Oil), (0.3 to 9) ng/g in SRM 1944 (New York/New Jersey Waterway Sediment), (0.2 to 0.4) ng/g in SRM 1945 (Organics in Whale Blubber), (1 to 18) ng/g in SRM 2974 (O rganics in Freeze-dried Mussel Tissue [Mytilus edulis]), and (0.1 to 0.4) n g/g in candidate SRM 1946 (Lake Superior Fish Tissue). PCB 169 was present at < 0.1 ng/g in SRMs 1944 and 2974.