BIOLOGICAL EFFECTS MONITORING OF THE NORTH-SEA EMPLOYING FISH EMBRYOLOGICAL DATA

Using the reproductive capacity of fish appears to be a suitable appro ach for risk assessment in the aquatic environment since fish are a ty pical representative thereof and in addition they are of considerable societal value. Generally the early embryonic stages are considered to be one of the most sensitive parts of a fish's life cycle. A method h as been developed to use the state of health of live, naturally spawne d fish embryos from plankton samples for biological effects monitoring . During the years 1985-1987 in the southern North Sea and in 1991-199 2 in the whole of the North Sea fish eggs were sampled from surface wa ters and examined for developmental abnormalities. Elevated embryo mal formation rates were detected in the plume of the major rivers Elbe an d Rhine as well as along the eastern coast of England. Occurring malfo rmations are thought to be pollution-related and may be used to define areas of environmental deterioration. The method is discussed in view of its suitability for biological effects monitoring using malformati ons in fish embryos as biomarkers.