From Environmental Science & Technology July 1993, Volume 27, Number 7 pg 1364 Missing PCBs and their relatives Traditional analyses for polychlorinated biphenyls (PCBs) in the environment do not include all the variations (congeners) of these toxic chemicals. Investigators from Stockholm University in Sweden report that a 1988 study of Swedish sediments and biological samples found that the rarely studied non-ortho-PCBs and polychlorinated napthalenes (PCNs) are widely distributed throughout the country. These compounds are structurally similar to the traditionally reported ortho-PCBs. PCNs appear to be as widespread in the environment as PCBs and even are found in remote areas such as Spitzbergen above the Arctic Circle. Moreover, they find that one of the non-ortho PCBs, PCB 126, may pose a greater threat to the environment than ortho-dioxins. Polychlorinated Biphenyls and Polychlorinated Napthalenes in Swedish Sediment and Biota. Ulf Jarnberg*, et. al. *Institute of Applied Environmental Research, Stockholm University, Solna, Sweden. For more information or copies of this highlighted article contact Alan Newman (202-872-6069, fax: 202-872-6060, Internet: arn96@acs.org, CompuServe: 71674,2564). Environmental Science & Technology is published monthly by the American Chemical Society, 1155 16th St, N.W., Washington, DC 20036.