of nuclear workers . Factors affecting recognition of cancer risks

Editor-Pristane (2,6,10,14-tetramethylpentadecane) is a branched chain hydrocarbon which is thought to be derived from the phytyl moiety of chlorophyll. This compound has been associated with several biological effects. Pristane can induce plasmacytomas,l and together with some polycyclic aromatic hydrocarbons, act as promoters in the development of Blymphoid malignancies and skin tumours in animals.2 3 Intraperitoneal injections have induced arthritis in mice.4 Pristane occurs in rather high concentrations, 1% to 3% of the body fat, in certain zooplankton and these plankton are assumed to be the primary source of the pristane found in liver oils of sharks and whales.' Pristane is also found in herring and the concentration in flesh is about 370 pg/g of wet weight. Other fish species such as cod have much lower concentrations of pristane in their flesh, most often < 1 yg/g of wet weight.6 One of us (BS) volunteered to ingest Atlantic herring as lunch at 11 00 am. Four different meals contained 125, 140, 250, and 310 g of cured herring. A reference meal was composed of chicken with potatoes, hard bread, and water. The quantitative analysis of pristane was performed with gas chromatography equipped with a flame ionisation detector. Pristane was also identified with