Assessment of tributyltin contamination based on imposex in Stramonita rustica (Mollusca: Gastropoda) along southern Bahia coast, northeastern Brazil

Abstract

This study investigated the effects of tributyltin (TBT) on the morphology of the genital system of the gastropod Stramonita rustica in southern Bahia, Brazil. For this, 330 specimens were collected during the summer of 2014 at eight sampling points to ascertain whether male sex organs had developed in addition to the complete female genital tract in females (= imposex). The analyses were made under a stereoscopic microscope. Imposex and their associated indexes, and the sterile females, exhibited the highest rates in harbors and shipyards areas. Despite the total ban of TBT in anti-fouling paints on a global scale since 2003, the results of this and other studies indicate the continued use of those paints on the Brazilian coast. This shows the inefficiency of existing legislation and the need to strengthen enforcement of the ban.Keywords: antifouling, sterilization, harbors, TBT. Avaliação da contaminação por tributil-estanho baseada em imposex em Stramonita rustica (Mollusca: Gastropoda) ao longo do Litoral Sul da Bahia ResumoEste estudo investigou os efeitos de tributil-estanho (TBT) sobre a morfologia do sistema genital do gastrópode Stramonita rustica (Lamarck, 1822) no Litoral Sul da Bahia, Brasil. Para isso, 330 espécimens foram coletados durante o verão de 2014 em oito pontos de amostragem, para verificar se os órgãos sexuais masculinos tinham se desenvolvido para além do trato genital feminino completo (= imposex). As análises foram feitas sob um microscópio estereoscópico. O imposex e seus índices associados, assim como as fêmeas estéreis, apresentaram as maiores taxas em áreas portuárias e estaleiros. Apesar da proibição total do TBT em tintas anti-incrustantes em escala global desde 2003, os resultados deste e de outros estudos indicam a continuidade de uso dessas tintas na costa brasileira. Isso mostra a ineficácia da legislação vigente e reforça a necessidade de se cumprir integralmente o banimento.Palavras-chave: antifouling, esterilização, portos, TBT.

Tributyltin and Zebrafish: Swimming in Dangerous Water

“…These animals show abnormalities and a decreased motility of spermatozoid, because this population produces a higher quantity of spermatozoids that lack flagella ( 16 ). This is in agreement with other reports in the literature which suggest that TBT is an imposex-inducing agent in other species ( 17 – 23 ) and with the finding of aromatase inhibitory ability of TBT. Aromatase is the enzyme responsible for the conversion of androgens into estrogens in cells (Figure 2 ).…”

Imposex in Stramonita haemastoma from coastal sites of Cartagena, Colombia

“…Some of those studies have linked the extent of the imposex level detected in specimens from Birds' Island to adverse effects such as low reproductive capacity or even complete sterility, affecting its health and survival capacity (Fernández et al, 2002). Although this is the first report for Cartagena, North of Colombia, imposex-related studies have also been documented for several species in other geographic locations in South America, including Brazil (Zeidan and Boehs, 2016;Fernández et al, 2002), Venezuela (Paz-Villarraga et al, 2015) and Ecuador (Castro et al, 2012).…”

Effects of Tributyltin Exposure in the Male Mammal’s Reproductive System: A Systematic Review

“…Although such usage is now under strict legislation, it remains a widespread environmental contaminant (13,14,15) still being detected in water, sediment, and urban runoff, generating unease about possible impacts on estuaries, freshwater, and coastal areas (16,17,18) . TBT is an endocrine disruptor which compromises reproductive capacity and sexual development in many species (19) .…”