Histological alterations in fish from Sydney reefs: possible biomarkers for environmental effects?

Abstract

This study examines the utility of histopathology in the damselfish, Parma microlepis, as a biomarker for the effects of organochlorine pesticides and hexachlorobenzene (HCB). Linkages between organochlorine residue concentrations and contaminant-associated histological effects in fish were examined using field collections and a manipulative field experiment. The distribution of 11 frequently identified organochlorines were measured in wild fish at different spatial scales, spanning 270 km of coastline centred around the Sydney region. Histopathology was used to investigate possible effects on liver, gills and gonad tissues in these fish. Pearson correlations and correlative multivariate statistical techniques were used to explore possible associations between concentrations of organochlorines in fish collected from the field and histological alterations in tissues. Only 6% of correlations between organochlorine residues and histological alterations in fish from field collections, were significant. A weak correlation was found between the occurrence of lamellar fusion in gills and the concentration of aldrin and dieldrin in a manipulative field experiment. A hypothetical model is suggested to explain these results.

Keywords::

• Biomarker Histopathology Organochlorines Damselfish Sydney