The effects of tributyltin (TBT) accumulation on adult dog-whelks, Nucella lapillus: long-term field and laboratory experiments

Abstract

Following treatment of the shells of adult Nucella lapillus with different marine paints under field conditions, the development of 'imposex' (the growth of a penis and vas deferens in females) was promoted by three TBT-based antifouling paints but not by a tin-free copper-based paint nor by yacht enamels.When adult animals were exposed to a range of sea-water leachates from TBT copolymer antifouling paint the initial rate of tin accumulation was approximately proportional to the ambient concentration over the range < 1-107 ng/1 of tin in the TBT fraction. In experiments of between 8 and 14 months duration, concentration factors (dry tissue/water) for tin (as TBT) reached about 10 5 at sea water concentrations of 1-5-18-7 ng/1. At 107 ng/1, however, the factor fell to about 3 x 10 4 owing probably to the accelerated degradation of TBT to DBT by the tissues. The bioaccumulation data from the laboratory experiments compare favourably with field data from populations around south-west England.At all experimental sea water concentrations, the bioaccumulation of tin by adult females was accompanied by increased development of imposex. However, the sterilisation of adult females through blockage of the oviduct by the vas deferens (as observed in declining field populations) occurred only after at least 12 months exposure to 107 ng/1 of tin as TBT: it also occurred after more than 18 months in some adults transplanted to a rocky shore exposed to a mean concentration of about 28 ng/1. Growing juveniles, on the other hand, are far more sensitive and may be sterilized at concentrations of only a few ng/1 before reaching maturity.The depuration of tin was followed for up to 9 months and, depending on the conditions, half-times for loss of the TBT fraction from the tissues ranged between about 50 days and more than 100 days. There was no evidence that loss of tin leads to any remission of imposex. I N T R O D U C T I O NPopulations of the gastropod, Nucella lapillus (L.), normally one of the commonest of rocky-shore macroinvertebrates, have recently suffered from declining numbers at many sites along the south coast of England. Bryan et al. (1986) showed that these declining populations exhibited a high degree of imposex (the induction of a penis and vas deferens in females) and that imposex was almost certainly caused by tributyltin (TBT) compounds leached from ships' antifouling paints. Evidence implicating TBT compounds in the development of imposex included: (1) a good relationship between the degree of imposex and the proximity of affected populations to harbours and marinas; (2) in Plymouth Sound, the degree of imposex increased dramatically between its discovery in 18-2

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).…”

Hydrobia ulvae imposex levels at Ria de Aveiro (NW Portugal) between 1998 and 2007: a counter-current bioindicator?

“…A well-known consequence of this pollution is imposex-the superimposition of male sexual characters onto prosobranch females 13 -which has been used as a biomarker of TBT environmental concentrations. [14][15][16][17] Three key indicator species have been used to monitor TBT pollution in Ria de Aveiro, namely: Nucella lapillus (L.), Nassarius reticulatus (L.) and Hydrobia ulvae (Pennant). In 1998, Barroso et al 3 recorded high levels of imposex in these species and the N. lapillus decreasing abundance from the system mouth inwards was attributed to the females' sterility caused by TBT.…”

Valuation of ecotoxicological impacts from tributyltin based on a quantitative environmental assessment framework

“…This research field is hampered by the limited knowledge of ecological impacts following exposure to hazardous chemical pollutants. However, the detrimental biological effects of tributyltin (TBT) on marine biota are well recognized (e.g., Bryan et al 1987;Fisher et al 1990) and negative impacts of TBT pollution on the marine environment in the Baltic Sea have been documented (Eklund et al 2008). TBT has previously been used in a risk-based analysis by Moore and Postle (1994), but the authors were unable to include non-market values in the impacts caused by the compound.…”