New implications in the use of imposex as a suitable tool for tributyltin contamination: experimental induction in Hexaplex trunculus (Gastropoda, Muricidae) with different stressors.
Imposex, i.e. the development of additional male sex organs (penis and/or vas deferens), in females of gonochorist marine and freshwater gastropods, is known to be caused by tributyltin (TBT), and it has been widely used as a biomonitoring tool in environmental surveys for TBT pollution assessment. In this study, we experimentally tested the potential to induce imposex by another endocrine disruptor (polychlorinated biphenyls [PCBs] mixture--Aroclor 1260). Adults of Hexaplex trunculus with low imposex level, coming from an Italian Marine Protected Area, were injected separately with different doses of tributyltin chloride (TBTCl) and Aroclor 1260. The compounds were dissolved in ethanol and the organisms were narcotised by immersion in MgCl(2) solution before injection. Before and after the experiment, butyltin compounds (BuTs) and PCB tissue concentrations were determined. A significant increase in imposex with respect to non-treated organisms was observed in all treatments, including artefact controls. No clear correlation was observed between BuTs and PCB tissue concentrations and indices of imposex incidence. Based on these results, no assumption can be formulated about PCB effect on imposex development. Nevertheless, they suggest that the imposex level increase, at least in H. trunculus, in laboratory conditions might not be caused by TBT only, but it would rather be a non-specific response to different stress stimuli.
Garaventa
Francesca
F
Department of Marine Technologies, CNR-Institute of Marine Sciences, Genoa, Italy. francesca.garaventa@ismar.cnr.it
Centanni
Elena
E
Fiorini
Sarah
S
Noventa
Seta
S
Terlizzi
Antonio
A
Faimali
Marco
M
Pavoni
Bruno
B
D000818:Animals; D012734:Disorders of Sex Development; D004784:Environmental Monitoring / Q000379:methods*; D005260:Female; D049851:Gastropoda / Q000187:drug effects* / Q000254:growth & development*; D008297:Male; D009947:Organotin Compounds / Q000032:analysis; D011078:Polychlorinated Biphenyls / Q000032:analysis / Q000633:toxicity; D014220:Trialkyltin Compounds / Q000032:analysis* / Q000633:toxicity; D014649:Vas Deferens / Q000187:drug effects; D014874:Water Pollutants, Chemical / Q000633:toxicity*
D009947:Organotin Compounds; D014220:Trialkyltin Compounds; D014874:Water Pollutants, Chemical; C062120:n-butyltin; C011559:tributyltin; D011078:Polychlorinated Biphenyls