Imposex

In the 1950s, organotin compounds were discovered to be highly effective in preventing the buildup of marine organisms on ship hulls, leading to their widespread use in antifouling paints by the 1960s. The use of these paints expanded rapidly during that decade. Around the late 1960s, researchers first observed imposex in the common dogwhelk, Nucella lapillus.{{cite journal |last1=Schøyen |first1=Merete |last2=Green |first2=Norman W. |last3=Hjermann |first3=Dag Ø. |last4=Tveiten |first4=Lise |last5=Beylich |first5=Bjørnar |last6=Øxnevad |first6=Sigurd |last7=Beyer |first7=Jonny |title=Levels and trends of tributyltin (TBT) and imposex in dogwhelk (Nucella lapillus) along the Norwegian coastline from 1991 to 2017 |journal=Marine Environmental Research |date=2019 |volume=144 |pages=1–8 |doi=10.1016/j.marenvres.2018.11.011|pmid=30497665 |bibcode=2019MarER.144....1S |hdl=11250/2622076 |hdl-access=free }}{{cite journal |last1=Blaber |first1=Stephen J. M. |title=The occurrence of a penis-like outgrowth behind the right tentacle in spent females of Nucella lapillus (L.) |journal=Journal of Molluscan Studies |date=1970 |volume=39 |issue=2–3 |pages=231–233 |doi=10.1093/oxfordjournals.mollus.a065097 |url=https://academic.oup.com/mollus/article-abstract/39/2-3/231/1060853?redirectedFrom=fulltext&login=true}} It was also observed 10 years later in another species, Ilyanassa obsoleta,{{cite journal |last1=Smith |first1=Blakeman S. |title=Sexuality in the american mud snail, Nassarius obsoletus say |journal=Journal of Molluscan Studies |date=1971 |volume=39 |issue=5 |pages=377–378 |doi=10.1093/oxfordjournals.mollus.a065117}} but it wasn't until 1981 that this phenomenon was directly linked to organotin exposure.{{cite journal |last1=Smith |first1=Blakeman S. |title=Male characteristics on female mud snails caused by antifouling bottom paints |journal=Journal of Applied Toxicology |date=1981 |volume=1 |issue=1 |pages=22–25 |doi=10.1002/jat.2550010106|pmid=7185870 }} Once the connection was made, pressure mounted to eliminate tributyltin (TBT) and related organotins from marine antifouling products due to their harmful environmental effects.

Although the majority of research on imposex has historically focused on marine species, organotin pollution and imposex are not restricted to exclusively marine habitats.{{cite journal |last1=Horiguchi |first1=Toshihiro |last2=Shiraishi |first2=Hiroaki |last3=Shimizu |first3=Makoto |last4=Yamazaki |first4=Sunao |last5=Morita |first5=Masatoshi |title=Organotin compounds and their effects on aquatic organisms, focusing on imposex in gastropods |journal=Main Group Metal Chemistry |date=1994 |volume=17 |issue=1-4 |doi=10.1515/MGMC.1994.17.1-4.81|doi-access=free }} The condition is known to affect estuarine species such as Heleobia australis,{{cite journal |last1=Neves |first1=Raquel A. F. |last2=Valentin |first2=Jean Louis |last3=Figueiredo |first3=Gisela M. |title=First record of imposex in Heleobia australis (Caenogastropoda: Cochliopidae) |journal=Journal of Molluscan Studies |date=2013 |volume=79 |issue=1 |pages=82–85 |doi=10.1093/mollus/eys034}} and also freshwater species such as apple snails (Pomacea spp.),{{cite journal |last1=Martínez |first1=María L. |last2=Piol |first2=María N. |last3=Sbarbati Nudelman |first3=Norma |last4=Verrengia Guerrero |first4=Noemí R. |title=Tributyltin bioaccumulation and toxic effects in freshwater gastropods Pomacea canaliculata after a chronic exposure: field and laboratory studies |journal=Ecotoxicology |date=2017 |volume=26 |issue=5 |pages=691–701 |doi=10.1007/s10646-017-1801-8|hdl=11336/72598 |hdl-access=free }}{{cite journal |last1=Jing-Ying |first1=Wu |last2=Pei-Jie |first2=Meng |last3=Ming-Yie |first3=Liu |last4=Yuh-Wen |first4=Chiu |last5=Li-Lian |first5=Liu |title=A High Incidence of Imposex in Pomacea Apple Snails in Taiwan: A Decade after Triphenyltin Was Banned |journal=Zoological Studies |date=2010 |volume=49 |issue=1 |pages=85-93 |url=https://zoolstud.sinica.edu.tw/Journals/49.1/85.pdf}} and the ramshorn apple snail (Marisa cornuarietis).{{cite journal |last1=Schulte-Oehlmann |first1=U. |last2=Bettin |first2=C. |last3=Fioroni |first3=P. |last4=Oehlmann |first4=J. |last5=Stroben |first5=E. |title=Marisa cornuarietis (Gastropoda, prosobranchia): a potential TBT bioindicator for freshwater environments |journal=Ecotoxicology |date=1995 |volume=4 |issue=6 |pages=372–384 |doi=10.1007/BF00118872}}

Imposex in marine gastropods is triggered by organotin compounds interfering with the hormonal regulation of sexual development. Although this link is well established, scientists have yet to agree on the precise biological mechanisms involved. Several competing theories propose that organotins disrupt different hormonal signaling pathways, including neuroendocrine, steroid-like, or retinoid (vitamin A-related) systems. It is also possible that multiple pathways contribute to the condition, though this has not been definitively confirmed.

In species such as the dog whelk, the growth of a penis in imposex females gradually blocks the oviduct, although ovule production continues. An imposex female dog whelk passes through several stages of penis growth before it becomes unable to maintain a constant production of ovules. Later stages of imposex lead to sterility and the premature death of the females of reproductive age, which can adversely affect the entire population.{{cite journal|last=Castro|first=Í. B.|year=2008|title=Imposex in endemic volutid from Northeast Brazil (Mollusca: Gastropoda)|journal=Brazilian Archives of Biology and Technology|location=Brazil|volume=51|issue=5|pages=1065–1069|issn=1516-8913|url=http://www.scielo.br/pdf/babt/v51n5/a24v51n5.pdf|doi=10.1590/s1516-89132008000500024|display-authors=etal|doi-access=free}}

Despite uncertainties surrounding the exact mechanisms, a 2006 study identified imposex as one of the few reliable biomarkers for assessing ecological risk and monitoring environmental health.{{cite journal |last1=Forbes |first1=Valery E. |last2=Palmqvist |first2=Annemette |last3=Bach |first3=Lis |title=The use and misuse of biomarkers in ecotoxicology |journal=Environmental Toxicology and Chemistry |date=2006 |volume=25 |issue=1 |pages=272–280 |doi=10.1897/05-257R.1|pmid=16494252 |bibcode=2006EnvTC..25..272F }} This is due to its high sensitivity, its specificity to organotin exposure, and the relatively well-understood nature of its biological effects. Additionally, imposex is not easily influenced by confounding environmental variables, and the condition in individual snails can be directly linked to broader impacts on population and community dynamics.

File:Tributyltin hydride.png

Initially, tributyltin (TBT), which can be active in extremely low concentrations, was believed to be the only inducer of imposex,Ruiz JM, Quintela M, Barreiro R (1998) [https://www.int-res.com/articles/meps/170/m170p293.pdf Tributyltin and imposex: no uncertainty shown.] Mar Ecol Prog Ser 170: 293–294 but recent studies reported other substances as inducers, such as triphenyltin (TPT){{cite journal|doi=10.1016/0025-326X(95)00133-8|last=Horiguchi|first=T.|year=1995|title=Imposex in Japanese gastropods (Neogastropoda and Mesogastropoda): effects of tributyltin and triphenyltin from anti-fouling paints|journal=Marine Pollution Bulletin|publisher=Oxford|volume=31|pages=402–405|issue=4–12|bibcode=1995MarPB..31..402H |display-authors=etal}} and ethanol.{{cite journal|doi=10.3354/meps158191|last=Davies|first=I. M.|year=1997|title=Sublethal effects of tributyltin oxide on thedog whelk Nucella lapillus|journal=Marine Ecology Progress Series|volume=158|pages=191–204|bibcode=1997MEPS..158..191D |display-authors=etal|doi-access=free}} Tributyltin (TBT) is thought to induce imposex primarily through inappropriate activation of the retinoid X receptor (RXR) pathway. RXR normally plays a role in reproductive development and endocrine signaling in gastropods. TBT acts as a high-affinity ligand for RXR, mimicking endogenous ligands such as 9-cis-retinoic acid, thereby triggering masculinization of female snails.{{cite journal |last1=Sternberg |first1=Robin M. |last2=Gooding |first2=Meredith P. |last3=Hotchkiss |first3=Andrew K. |last4=LeBlanc |first4=Gerald A. |title=Environmental-endocrine control of reproductive maturation in gastropods: implications for the mechanism of tributyltin-induced imposex in prosobranchs |journal=Ecotoxicology |date=2010 |volume=19 |issue=1 |pages=4–23 |doi=10.1007/s10646-009-0397-z|pmid=19653098 |bibcode=2010Ecotx..19....4S }}

Aside from its use in antifouling paints, TBT is widely employed in products such as fungicides, wood preservatives, PVC stabilisers, and catalysts, creating additional sources of pollution. TBT and its main breakdown products, dibutyltin and monobutyltin, are commonly found in marine waters and sediments worldwide, but also appear in the surface waters and sediments of rivers and lakes, especially near areas with heavy boat traffic. In water, TBT can break down through chemical processes and sunlight, with a half-life ranging from 6 to 126 days. Its biological breakdown in freshwater and seawater usually takes between 6 days and several weeks.{{cite journal |last1=Rüdel |first1=Heinz |title=Case study: bioavailability of tin and tin compounds |journal=Ecotoxicology and Environmental Safety |date=2003 |volume=56 |issue=1 |pages=180–189 |doi=10.1016/S0147-6513(03)00061-7}} In sediments, especially those without oxygen, it degrades much more slowly, sometimes taking months or even up to 20 years.{{cite journal |last1=Dowson |first1=P.H. |last2=Bubb |first2=J.M. |last3=Lester |first3=J.N. |title=Persistence and Degradation Pathways of Tributyltin in Freshwater and Estuarine Sediments |journal=Estuarine, Coastal and Shelf Science |date=1996 |volume=42 |issue=5 |pages=551–562 |doi=10.1006/ecss.1996.0036 |url=10.1006/ecss.1996.0036 |language=en}} While the harmful effects of TBT on marine ecosystems are well known, much less research has focused on its impacts in freshwater systems.

{{Main|List of species affected by imposex}}

In the late 1970’s, imposex had been recognized in at least 34 gastropod species.{{cite journal |last1=Jenner |first1=Martha Garrett |title=Pseudohermaphroditism in Ilyanassa obsoleta (Mollusca: Neogastropoda) |journal=Science |date=1979 |volume=205 |issue=4413 |pages=1407–1409 |doi=10.1126/science.472758}} This number had increased to at least 100 species a decade later,{{cite journal |last1=Fioroni |first1=P. |last2=Oehlmann |first2=J. |last3=Stroben |first3=E. |title=The pseudohermaphroditism of prosobranchs; morphological aspects. |journal=Zoologischer Anzeiger |date=1991 |volume=226 |pages=1-26 |url=http://www.vliz.be/en/imis?refid=221881 |language=en}}and by 1994, it had been verified in females of at least 195 species worldwide.{{cite journal |last1=Horiguchi |first1=T. |last2=Shiraishi |first2=H. |last3=Shimizu |first3=M. |last4=Morita |first4=M. |title=Imposex and organotin compounds in Thais clavigera and T. bronni in Japan |journal=Journal of the Marine Biological Association of the United Kingdom |date=1994 |volume=74 |issue=3 |pages=651–669 |doi=10.1017/S002531540004772X|bibcode=1994JMBUK..74..651H }} The records continued to increase to a total of 260 species from marine and freshwater environments in the following 15 years.{{cite journal |last1=Hiromori |first1=Youhei |last2=Nishikawa |first2=Jun-ichi |last3=Yoshida |first3=Ichiro |last4=Nagase |first4=Hisamitsu |last5=Nakanishi |first5=Tsuyoshi |title=Structure-dependent activation of peroxisome proliferator-activated receptor (PPAR) γ by organotin compounds |journal=Chemico-Biological Interactions |date=2009 |volume=180 |issue=2 |pages=238–244 |doi=10.1016/j.cbi.2009.03.006|pmid=19497422 |bibcode=2009CBI...180..238H }}

Countries in which imposex has been documented in gastropods include:

{{div col|colwidth=20em}}

;Africa

• South Africa

;Asia

• Indonesia{{cite journal |last1=Rumampuk |first1=N. D. C. |last2=Schaduw |first2=J. N. W. |last3=Lintang |first3=R. A. J. |last4=Rompas |first4=R. M. |title=Imposex phenomenon in gastropods from Bitung waters, North Sulawesi, Indonesia |journal=AACL Bioflux |date=2019 |volume=12 |issue=2 |url=https://www.cabidigitallibrary.org/doi/pdf/10.5555/20193362009 |issn=1844-9166}}

• Japan
• Singapore
• Thailand

;Europe

• England
• Greenland
• Iceland
• Italy
• Portugal
• Scotland
• United Kingdom
• The Netherlands

;North America

• Canada
• Mexico{{cite journal |last1=Domínguez-Ojeda |first1=Delia |last2=Patrón-Soberano |first2=Olga Araceli |last3=Nieto-Navarro |first3=José Trinidad |last4=Robledo-Marenco |first4=María de Lourdes |last5=Velázquez-Fernández |first5=Jesús Bernardino |title=Imposex in Plicopurpura pansa (Neogastropoda: Thaididae) in Nayarit and Sinaloa, Mexico |journal=Revista Mexicana de Biodiversidad |date=2015 |volume=86 |issue=2 |pages=531–534 |doi=10.1016/j.rmb.2015.04.018}}
• Panama{{cite journal |last1=Batista-Andrade |first1=Jahir Antonio |last2=Caldas |first2=Sergiane Souza |last3=Batista |first3=Rodrigo Moço |last4=Castro |first4=Italo Braga |last5=Fillmann |first5=Gilberto |last6=Primel |first6=Ednei Gilberto |title=From TBT to booster biocides: Levels and impacts of antifouling along coastal areas of Panama |journal=Environmental Pollution |date=2018 |volume=234 |pages=243–252 |doi=10.1016/j.envpol.2017.11.063}}
• United States

;Oceania

• Australia
• New Zealand

;South America

• Argentina{{cite journal |last1=Penchaszadeh |first1=Pablo E. |last2=Averbuj |first2=Andrés |last3=Cledón |first3=Maximiliano |title=Imposex in Gastropods from Argentina (South-Western Atlantic) |journal=Marine Pollution Bulletin |date=2001 |volume=42 |issue=9 |pages=790–791 |doi=10.1016/s0025-326x(01)00098-4 |url=http://dx.doi.org/10.1016/s0025-326x(01)00098-4|hdl=11336/137339 |hdl-access=free }}
• Brazil{{cite journal|last=Castro|first=Í. B.|year=2008|title=Imposex in endemic volutid from Northeast Brazil (Mollusca: Gastropoda)|journal=Brazilian Archives of Biology and Technology|location=Brazil|volume=51|issue=5|pages=1065–1069|issn=1516-8913|url=http://www.scielo.br/pdf/babt/v51n5/a24v51n5.pdf|doi=10.1590/s1516-89132008000500024|display-authors=etal|doi-access=free}}
• Chile
• Ecuador{{cite journal |last1=Castro |first1=Ítalo Braga |last2=Machado |first2=Fabiano Bender |last3=de Sousa |first3=Gabriela Tavares |last4=Paz-Villarraga |first4=César |last5=Fillmann |first5=Gilberto |title=How protected are marine protected areas: A case study of tributyltin in Latin America |journal=Journal of Environmental Management |date=2021 |volume=278 |pages=111543 |doi=10.1016/j.jenvman.2020.111543 |url=https://www.sciencedirect.com/science/article/pii/S0301479720314687}}
• Peru{{cite journal |last1=Enrique |first1=Seid |last2=Guabloche |first2=Angélica |last3=Tuesta |first3=Eduardo |last4=Iannacone |first4=Jose |last5=Castro |first5=Italo Braga |title=Imposex responses in Thaisella chocolata and Xanthochorus buxeus from Callao harbor, Peru |journal=Regional Studies in Marine Science |date=2019 |volume=26 |pages=100510 |doi=10.1016/j.rsma.2019.100510 |url=https://www.sciencedirect.com/science/article/pii/S235248551830611X}}
• Venezuela{{cite journal |last1=Miloslavich |first1=P. |last2=Penchaszadeh |first2=P. E. |last3=Bigatti |first3=G. |title=Imposex en gastrópodos de Venezuela |journal=Ciencias Marinas |date=2007 |volume=33 |issue=3 |pages=319–324 |url=https://www.scielo.org.mx/scielo.php?pid=S0185-38802007000300009&script=sci_arttext |language=es |issn=0185-3880}}

{{div col end}}

Long-term monitoring studies have demonstrated that the prevalence of imposex in marine gastropods is directly correlated with TBT concentrations in the environment. A comprehensive study conducted along the Norwegian coastline from 1991 to 2017 evaluated the levels of TBT and imposex in populations of the dogwhelk (Nucella lapillus). The study documented a significant decline in both TBT concentrations and imposex incidence following the implementation of national and international bans on TBT-based antifouling paints. However, the rate of recovery varied among different localities. This variation was attributed to factors such as sediment characteristics, historical pollution levels, and hydrodynamic conditions, which influence the persistence of TBT in the environment.

In 1993, Scientists from the Plymouth Marine Laboratory found a thriving dog-whelk population in the

Dumpton Gap, near Ramsgate in the UK despite high levels of TBT in the water.Gibbs, Journal of the Marine Biological Association, 1993, vol 73, p 667 In the Dumpton Gap population, only 25% of females showed any significant signs of imposex, while 10% of males were characterized by the absence of a penis or an undersized penis, with incomplete development of the vas deferens and prostate. After further experiments, scientists concluded that "Dumpton Syndrome" was a genetic selection caused by high TBT levels. TBT-resistance was improved at the cost of lower reproductive fitness.{{cite journal |last1=Quintela |first1=M |last2=Barreiro |first2=R |last3=Ruiz |first3=J.M |title=Dumpton Syndrome reduces the tributyltin (TBT) sterilising effect on Nucella lapillus (L.) by limiting the development of the imposed vas deferens |journal=Marine Environmental Research |date=2002 |volume=54 |issue=3–5 |pages=657–660 |doi=10.1016/s0141-1136(02)00154-x|pmid=12408631 |bibcode=2002MarER..54..657Q }}

In 2024, the first recorded case of imposex in Triplofusus giganteus (the largest marine gastropod in the Atlantic) was reported in Florida. Three out of four wild-collected females exhibited pseudopenis structures, histologically confirmed to contain vas deferens tissue. This discovery was significant given the species’ limited reproductive capacity and ecological importance as a top predator.{{cite journal |last1=Leal |first1=José H |last2=Hulse |first2=Carly |last3=D'Agostino |first3=Claire |last4=Fogelson |first4=Susan |title=First record of imposex in the horse conch, Triplofusus giganteus (Mollusca: Gastropoda: Fasciolariidae) |journal=Bulletin of Marine Science |date=2024 |volume=101 |issue=2 |pages=899–900 |doi=10.5343/bms.2024.0104}}

Several marine gastropods serve as sensitive bioindicators for assessing TBT pollution through the measurement of imposex levels. The Vas Deferens Sequence Index (VDSI) is a standardized metric employed to quantify the severity of imposex in affected populations. OSPAR utilizes this index to evaluate ecological quality and the success of pollution mitigation strategies.{{cite web |last1=Ltd |first1=Michael Carder |title=Status and Trends in the Levels of Imposex in Marine Gastropods (TBT in Shellfish) |url=https://oap.ospar.org/en/ospar-assessments/quality-status-reports/qsr-2023/indicator-assessments/tbt-shellfish/ |website=oap.ospar.org |publisher=Convention for the Protection of the Marine Environment of the North-East Atlantic |access-date=29 May 2025 |language=en}} Due to their high sensitivity to TBT and other organotin compounds, several gastropod species, such as Nucella lapillus in Europe and Lepsiella scobina in New Zealand, have become established bioindicators for organotin contamination. In the case of L. scobina, the intensity of imposex correlates with environmental TBT levels and has been used to map contamination in coastal waters.{{cite journal |last1=Stewart |first1=C. |last2=De Mora |first2=S. J. |last3=Jones |first3=M. R. |last4=Miller |first4=M. C. |title=Imposex in New Zealand neogastropods |journal=Marine Pollution Bulletin |date=1992 |volume=24 |issue=4 |pages=204–209|doi=10.1016/0025-326X(92)90531-A |bibcode=1992MarPB..24..204S }}

A study published in 2011 reported that imposex levels are elevated in dog conch (Laevistrombus canarium) populations located near Malaysian ports. However, the researchers found no evidence of sterility among affected females. Their findings suggest that females of L. canarium commonly develop a penis when exposed to organotin compounds in seawater, but this condition does not result in sterility for this species. The dog conch’s ability to tolerate imposex without reproductive failure makes it a reliable local bioindicator for organotin contamination.{{cite journal|last=Cob|first=Z. C.|author2=Arshad, A. |author3=Bujang, J. S. |author4= Ghaffar, M. A. |title=Description and evaluation of imposex in Strombus canarium Linnaeus, 1758 (Gastropoda, Strombidae): a potential bio-indicator of tributyltin pollution|journal=Environmental Monitoring and Assessment|year=2011|volume=178|issue=1–4|pages=393–400|doi=10.1007/s10661-010-1698-7|pmid=20824325|bibcode=2011EMnAs.178..393C |s2cid=207130813|url=http://psasir.upm.edu.my/id/eprint/23629/1/Description%20and%20evaluation%20of%20imposex%20in%20Strombus%20canarium%20Linnaeus.pdf}}

Major international organizations, including the Oslo-Paris Commission, the European Commission, and the International Maritime Organization (IMO), played crucial roles in driving the global effort to restrict the use of TBT. The first national bans on TBT-based paints for recreational boats and vessels under 25 meters in length were introduced in the late 1980s and early 1990s. Norway implemented this restriction in 1990 and extended it to larger vessels over 25 meters in 2003. A worldwide ban on TBT in all antifouling paints officially came into effect in January 2008. TBT-based compounds were included in the Rotterdam Convention and have been banned by the International Convention on the Control of Harmful Anti-fouling Systems on Ships.{{Cite book |last=FAO. |first=Secretariat of the Rotterdam Convention on the Prior Informed Consent Procedure for Certain Hazardous Chemicals and Pesticides in International Trade. United Nations Environment Programme. |url=http://worldcat.org/oclc/1248029257 |title=Rotterdam Convention on the Prior Informed Consent Procedure for Certain Hazardous Chemicals and Pesticides in International Trade : text and annexes. |date=2015 |publisher=Rotterdam Convention Secretariat |oclc=1248029257}}{{cite journal |last1=Uc-Peraza |first1=Russell G. |last2=Castro |first2=Ítalo B. |last3=Fillmann |first3=Gilberto |title=An absurd scenario in 2021: Banned TBT-based antifouling products still available on the market |journal=Science of The Total Environment |date=2022 |volume=805 |pages=150377 |doi=10.1016/j.scitotenv.2021.150377 |url=10.1016/j.scitotenv.2021.150377 |language=en}} Today, TBT is classified as a priority hazardous substance under both the Water Framework Directive and the Marine Strategy Framework Directive within the European Union.

In the early 1990s, several coastal nations, including Norway, began monitoring TBT levels and the occurrence of imposex in their coastal waters. Not long after the initial bans on TBT-based paints were implemented, snail populations in some of the most heavily impacted areas began to show signs of recovery. Nevertheless, while there have been partial recoveries of gastropod populations and a decline in imposex prevalence, several reports have documented persistent imposex cases. A ban on tributyltin was implemented in Canada in 2003, however, in 2006, dog whelks with imposex could still be found on the shores of Halifax Harbour in Nova Scotia.{{cite journal |last1=Coray |first1=Camille |last2=Bard |first2=Shannon M. |title=Persistence of Tributyltin-Induced Imposex in Dogwhelks (Nucella lapillus) and Intersex in Periwinkles (Littorina littorea) in Atlantic Canada |journal=Water Quality Research Journal |date=1 May 2007 |volume=42 |issue=2 |pages=111–122 |doi=10.2166/wqrj.2007.014 |doi-access=free|bibcode=2007WQJR...42..111C }} Similar situations have emerged involving other species such as Triplofusus giganteus, Strombus pugilis, and Melongena melongena, which indicates that TBT may still linger in sediments or continue to impact large-bodied, long-lived species or rather may still be widely used clandestinely.{{cite journal |last1=Meza-Morelos |first1=Dairo |last2=Johnson Restrepo |first2=Boris |last3=Braga Castro |first3=Ítalo |last4=Fillmann |first4=Gilberto |last5=Fernández Maestre |first5=Roberto |title=Imposex incidence in gastropod species from the Colombian Caribbean Coast reveals continued and widespread tributyltin contamination after its global ban |journal=Environmental Pollution |date=2024 |volume=362 |pages=125010 |doi=10.1016/j.envpol.2024.125010|pmid=39313126 }}

• Environmental issues with paint
• Organotin chemistry

{{reflist|2}}

• Horiguchi, Toshihiro (2009). [https://link.springer.com/chapter/10.1007/978-4-431-85709-9_7 Mechanism of Imposex Induced by Organotins in Gastropods.] In: Arai, T., Harino, H., Ohji, M., Langston, W.J. (eds) Ecotoxicology of Antifouling Biocides. Springer, Tokyo.{{ISBN|978-4-431-85709-9}}
• Horiguchi, Toshihiro (2016). [https://link.springer.com/book/10.1007/978-4-431-56451-5 Biological effects by organotins.] New York, NY: Springer Berlin Heidelberg. {{ISBN|978-4-431-56449-2}}

• [http://www.eea.europa.eu/publications/environmental_issue_report_2001_22/issue-22-part-13.pdf Tributyltin (TBT) antifoulants: a tale of ships, snails and imposex].
• "[https://web.archive.org/web/20060115152109/http://www.nrm.gov.au/monitoring/indicators/estuarine/occurrence-of-imposex.html Occurrence of Imposex.]" Natural Resource Management. 2006.

Category:Animal diseases

Category:Environmental impact of shipping

Category:Gastropods

Category:Marine biology

Category:Ocean pollution