Imposex in the indigenous Nassarius kraussianus (Mollusca: Neogastropoda) from South African harbours.
Nassarius kraussianus populations in the Durban and Richards Bay harbours (along the eastern seaboard of southern Africa) and in the Knysna lagoon (southern Cape coast) showed imposex development, confirming bioavailability of tributyltin (TBT) in these waterways. Incidence of imposex (which ranged from 29% to 100%) and relative penis length of females (RPL; which ranged from 1.3% to 55.2%) were markedly variable among populations from different sites in each waterway, indicative of localised effects of TBT contamination. Shell length of the snails was apparently not correlated with contamination level, as assessed from imposex measurements. While population imposex features are easy to determine and often provide a sensitive biomarker of TBT exposure, the discussion outlines reservations when extrapolating these to general ecological situations. Additionally, this study represents the first published report on the topic for sub-Saharan, African harbours, some of which seem remarkably less affected than suggested for other world regions.
Marshall
David J
DJ
School of Life and Environmental Sciences, University of Durban-Westville, Private Bag X54001, Durban 4000, South Africa. marshall@pixie.udw.ac.za
Rajkumar
Anisha
A
D000818:Animals; D001682:Biological Availability; D015415:Biomarkers / Q000032:analysis; D012734:Disorders of Sex Development / Q000139:chemically induced* / Q000662:veterinary; D004784:Environmental Monitoring; D008974:Mollusca / Q000033:anatomy & histology / Q000254:growth & development*; D010571:Pest Control; D012680:Sensitivity and Specificity; D013019:South Africa; D014220:Trialkyltin Compounds / Q000493:pharmacokinetics / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000493:pharmacokinetics / Q000633:toxicity*
D015415:Biomarkers; D014220:Trialkyltin Compounds; D014874:Water Pollutants, Chemical; C011559:tributyltin