ECOTOXICOLOGICAL DETERMINATION OF PIGMENTED SALMON SYNDROME - A PATHOLOGICAL CONDITION OF ATLANTIC SALMON ASSOCIATED WITH RIVER POLLUTION

The 'Pigmented Salmon Syndrome' is a noninfectious haemolytic anaemia with associated clinical jaundice of Atlantic salmon (Salmo salar), ca used by exposure to a combination of chemical pollutants. The disease has been restricted to the migrating adult Atlantic salmon population of the River Don, Aberdeenshire, Scotland, UK, where it reached epidem ic proportions in the early 1980s. Effluents from paper mills, from th e oil-servicing industry and from an airport were implicated as causat ive factors in the syndrome. Subsequent experiments showed that sympto ms of the syndrome could be reproduced by the sequential or combined e xposure to petroleum hydrocarbons (such as diesel) and resin acids. Th e Pigmented Salmon Syndrome has not recurred in wild River Don salmon since 1989, and our research suggests that this is due to directed imp rovements in the water quality of the River Don. The disease is a good example of how multiple contaminants can collectively cause biologica l effects which are not apparent from exposure to single substances. T his article describes how the causes of the disease were determined.