Kinetics of the development of imposex in transplanted adult dogwhelks, Nucella lapillus

The degree of imposer in dogwhelks, Nucella lapillus (L.), is normally desc ribed in terms of a series of vas deferens development stages. The progress ion of adult female dogwhelks through vas deferens stages 0-5 in response t o exposure to tributyltin at 2-128 ng/l has been modelled on the basis of f irst-order kinetics. Modelling indicated that the half-lives of stages 0, 1 and 2 were from 1-8 weeks and that the half-life of stage 3 was approximat ely twice as long. The hall-life of stage 4 was 90-120 weeks. Half-lives de creased with increasing exposure concentration. The implications of these d ata for field surveys and transplantation experiments are discussed. Transp lanted dogwhelks will not rapidly attain equilibrium with environmental con ditions. Experiments will require careful control of exposure period, and p referable supporting chemical data. Crown Copyright (C) 2000 Published by E lsevier Science Ltd. All rights reserved.