AN ASSESSMENT OF SEDIMENT TOXICITY IN THE RIVER TYNE ESTUARY, UK BY MEANS OF BIOASSAYS

This paper describes an evaluation of the toxicity of contaminated sed iments obtained in June 1992 from six intertidal stations on a 25 km s tretch of the industrialised River Tyne Estuary in northeast England. The bioassays for toxicity included the amphipod Corophium spp, and th e polychaete Arenicola marina whole sediment tests, as well as tests o n elutriates with the copepods Tisbe battagliai and Acartia tonsa, the embryo of the oyster Crassostrea gigas, the light-emitting bacterium Photobacterium phosphoreum and the unicellular algae Tetraselmis sueci ca and Thalassiosira pseudonana, Tisbe battagliai was also tested with pore water samples from some stations, The sediment samples were anal ysed for a wide range of chemicals. These analyses showed that contami nants were present at particularly high concentrations at one of the s tations (River Team confluence), and this was reflected in the results obtained with the whole-sediment bioassays. Detailed studies at this station showed that contamination varied markedly over distances of a few metres. On the other hand, the elutriate and pore water tests gave results which were not clearly linked to the distribution of measured contaminants among the six stations. The implications of these result s for the use of sediment toxicity bioassays in environmental monitori ng are discussed. Crown Copyright (C) 1998 Published by Elsevier Scien ce Ltd.