Endocrine disruption in the shore crab Carcinus maenas - A biomarker for benthic marine invertebrates?

Abstract

A considerable amount of research has been conducted on the effects of certain contaminants that have the potential to impact the endocrine systems that regulate vital life processes in freshwater and marine fishes. There is, however, a relative paucity of information on aquatic and especially benthic marine invertebrate species, many of which could be seriously impacted by sewage effluent and industrial discharges. The present study used a combination of end-points to assess possible endocrine disruption in a marine crustacean, the shore crab Carcinus maenas. These included pheromonally mediated sexual behaviour, exoskeletal morphological measures, quantities of steroid moulting hormones (i.e. ecdysteroids) and the presence of the egg yolk protein, vitellin in male crabs. Crabs were collected from sites known to elicit high oestrogenic responses in vertebrates and also from coastal reference sites. The results suggest that shore crabs around the coast of the Great Britain show effects consistent with pollutant-mediated endocrine disruption. These include a reduced behavioural response to the female sex pheromone, morphometric abnormalities such as reduced pleopod-length ratios and enlarged abdomen width, enhanced steroid moulting-hormone (ecdysone equivalent) levels and the detection of vitellin-like proteins in the hepatopancreas of male crabs. This multilevel approach may have significant potential for investigating endocrine disruption in marine crustaceans. © Inter-Research 2005.