The use of sediment analogues to study the uptake of pollutants by chironomid larvae

A technique is described that uses artificial resin beads with known surfac e properties to investigate the factors influencing the bioaccumulation of pollutants from sediments. One advantage of this technique is that it provi des a standard procedure against which it is possible to calibrate natural sediments with their diverse properties. The method has been used on third instar larvae of the midge Chironomus riparius and the results are compared with previous studies on the worm Lumbriculus variegatus. The use of a sta ndard test using resin beads as a substitute for natural sediment allows co mparisons to be made between species and substrates. Thus, the bioaccumulat ion factors for the midge larvae are much smaller than those of the worm an d this correlates with the ability of the insect larva to detoxify many pol lutants. It is also possible to use the test to identify if ingestion of th e sediment increases the bioaccumulation of contaminants and whether this i nvolves the release of pollutants by digestive processes or not. (C) 2001 E lsevier Science Ltd. All rights reserved.