PCBs are a group of 209 congeners of highly lipophilic persistant organic pollutants. They are a concern because they bioaccumulate in food chains and are excreted in breast milk. The purpose of this article is to explore whether PCBs are carcinogens and if so what risk they pose. To facilitate a clear understanding of a complicated and controversial subject for non-scientists the perspective is that of a general practitioner. A PubMed search for review articles was performed in addition to information found on internet pages of renowned international and national organizations. A total of 12 assessments are discussed. Animal studies are generally assessed as giving strong evidence of hepatocarcinogenesis, and also tumor-promoter abilities. The human evidence is not conclusive but some epidemiological mortality studies and case-control studies found significant increases in hepatobiliary cancer, malignant melanoma and Non-Hodgkins lymphoma. Altogether the evidence indicates that PCBs are human carcinogens. Very few studies explore individual congeners, but some cell and animal research supports both dioxin-like and non-dioxinlike PCBs being carcinogens and tumorpromoters. The risks of PCBs are neither well documented nor understood. The Ah-receptor based model of TEQ/TEF is not scientifically sound enough to be exclusively used in risk assessments. Research in molecular/cell biology is needed to approach a better understanding of mechanisms of cancer. Thus a new model of risk assessment can be developed. Until that time a conservative approach is indicated. Therefore children and women of or under childbearing age should avoid sources rich in PCBs, such as farmed salmon.