A Comparison of the Effectiveness of Tri-N-Butyltin Chloride and Five other Organotin Compounds in Promoting the Development of Imposex in the Dog-Whelk, Nucella Lapillus

Abstract

Dog-whelks, Nucella lapillus, already slightly affected by imposex, were exposed to dissolved tri-n-butyltin (TBT) and other organotins at nominal sea water concentrations of 200 ng/1 (as tin) for 14 d and then returned to the shore for up to 203 d. In response to TBT, the penes of females increased in size and the relative penis size (RPS) index rose to 44% compared with 6% in the controls. For tri-n-propyltin (TPrT) the index increased significantly to 14 % but the increase caused by tetrabutyltin (TTBT) was only marginally significant. No effect was produced by dibutyltin (DBT) or triphenyltin (TPhT). However, analyses of the tissues showed that the less effective compounds were not as efficiently accumulated as TBT or TPrT.To overcome the problem of differential absorption through the body wall, organotins were injected. Females were then maintained in the laboratory for up to 105 d. Again TBT was most effective in promoting imposex, but the effect of TTBT was now appreciably greater than that of TPrT. Injections of DBT, TPhT and monobutyltin had no effect on imposex. It is concluded that the development of imposex in N. lapillus is not a totally specific response to TBT since a similar but much smaller response is caused by TPrT; the latter does not appear to result from TBT contamination of the compound used. However, the effect of TTBT is probably caused by contamination with TBT and by its degradation to TBT in the body tissues of N. lapillus.

Environmental Endocrine Disruption: An Effects Assessment and Analysis

“…TBT has been found in bivalve mollusks and fish species eaten by man, although levels of these residues in edible tissues (e.g., 0.08 to 0.9 mg/kg in salmon in the United States, and < 10 to 5600 pg/kg in Chesapeake Bay oysters) are considered to be safe levels (313 (314) found that periwinkle (Littorina littorea) in two British estuaries showed steady population increases as TBT residues in water and sediments declined as a result of the partial ban on TBT use in 1987 by the United Kingdom. Unlike the dogwhelk, the periwinkle does not undergo imposex in response to TBT exposure, which results in decreased egg production due to blockage of the genital pore (311,314,315). Nonetheless, a slightly different masculinizing phenomenon correlated with TBT exposures has been observed in periwinkles-intersex (315).…”

“…Although these compounds can be active against some insect species and not others, studies have documented the sensitivity of certain nontarget arthropods, especially crustaceans, to these compounds (287)(288)(289)(290)(291)(292)(293)(294). In addition to insect growth regulators, the well-known case of DDT and its effects on avian eggshell thinning has been linked to endocrine pathways (295 (311) found that populations of the dog-whelk snail (Nucella lapillus) were disappearing or diminishing in many locations along the United Kingdom coast (310)]; N. lapillus does not occur in the Northeast Pacific). Imposex could be confirmed in all but one species of snail (Amphissa columbiana, Dall).…”

Generalized system of imposex and reproductive failure in female gastropods of coastal waters of mainland China

“…Therefore, the present results clearly indicate that imposex is not only widespread but also severe in the coastal waters of mainland China. Imposex can be induced by tributyltin (TBT) at concentrations as low as the ng Sn l -1 level (Bryan et al 1987(Bryan et al , 1988. TBT has been detected (> 0.5 ng Sn l ) (Jiang et al 2001).…”

“…This masculinization can lead to reproductive failure in females and even to the extinction of populations (Gibbs & Bryan 1986). Imposex is mainly induced by organotin compounds used as biocides in antifouling paints (Smith 1981a,b,c, Bryan et al 1987, 1988. To date, more than 170 species of gastropods, represented by 28 families, have been shown to be affected by imposex , deFur et al 1999, Horiguchi et al 2000; see Appendix 1, www.intres.com/articles/suppl/m304p179_app.pdf).…”

Organotin pollution in China: An overview of the current state and potential health risk

“…Such masculinization causes reproductive failures in females and thus can cause the extinction of entire populations (Gibbs and Bryan, 1986). The presence of organotin compounds used as biocides in antifouling paints has been shown to induce imposex (Smith, 1981a(Smith, , 1981b(Smith, , 1981cBryan et al, 1987Bryan et al, , 1988. In total, imposex has been documented in over 150 gastropod species (Matthiessen et al, 1999).…”