thumb|right|This female specimen of the queen conch, Aliger gigas, shows signs of imposex: it has developed a male sexual organ (verge) due to previous exposure to [[organotin compounds.]] Imposex is a disorder observed in certain marine and freshwater gastropod mollusks, where female individuals develop male sexual characteristics, such as a penis and vas deferens, due to exposure to specific environmental pollutants. This condition is primarily induced by organotin compounds, notably tributyltin (TBT), which have been widely used in antifouling paints for ships to prevent biofouling. Unlike
thumb|right|This female specimen of the queen conch, Aliger gigas, shows signs of imposex: it has developed a male sexual organ (verge) due to previous exposure to [[organotin compounds.]] Imposex is a disorder observed in certain marine and freshwater gastropod mollusks, where female individuals develop male sexual characteristics, such as a penis and vas deferens, due to exposure to specific environmental pollutants. This condition is primarily induced by organotin compounds, notably tributyltin (TBT), which have been widely used in antifouling paints for ships to prevent biofouling. Unlike intersex conditions that involve gonadal ambiguity, imposex results in the superimposition of male genitalia onto otherwise functional female reproductive anatomy, often leading to sterility and population declines in affected species.
The phenomenon was first documented in the 1960s and has since been identified in over 260 gastropod species worldwide. Imposex serves as a sensitive bioindicator for monitoring organotin pollution in marine environments. The severity of imposex is often quantified using the Vas Deferens Sequence Index (VDSI), which assesses the progression of male organ development in females.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).