Metabolism of Bis(Tributyltin)Oxide by Estuarine Animals

Lee, R.

doi:10.1109/oceans.1986.1160361

Cited by 38 publications

(19 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In vertebrates and many invertebrates, including molluscs, a multifunctional oxygenase (MFO) system exists which catalyses the conversion of androgens to estrogens (Kirchin et al, 1988;Livingstone et al, 1989Livingstone et al, , 1990Payne et al, 1991). The same MFO system is believed to be responsible for the TBT debutylation (Lee, 1985(Lee, , 1986. We presume that TBT leads to a competitive inhibition of the cytochrome P-450 dependent aromatase and consequently to an increase in the androgen level.…”

Section: Resultsmentioning

confidence: 90%

TBT-induced imposex in marine neogastropods is mediated by an increasing androgen level

Bettin

Oehlmann

Stroben

1996

Helgolander Meeresunters

299

183

View full text Add to dashboard Cite

Tributyltin (TBT) exposure at different concentrations (5, 50, and 100 ng TBT as Sn/1) induces a concentration-and time-dependent imposex (= pseudohermaphroditism) development in female Nucella lapillus and Hinia reticulata. In both species the average imposex stage, termed as vas deferens sequence (VDS) index, and the average female penis length increases with increasing TBT concentration and duration of TBT exposure. Testosterone added at a concentration of 500 ng/1 induces a faster and more intensive imposex development compared to that induced by the TBT concentrations used in the present experiments. Radioimmunological determination of endogenous steroid content reveals increasing testosterone titres in female gastropods exposed to TBT which correlate with the TBT concentration used and the duration of the experiment. The most marked and highest increase of the endogenous testosterone level is exhibited by females of both species exposed to testosterone. Simultaneous exposure to TBT and to the antiandrogen cyproterone acetate which suppresses imposex development completely in N. lapillus and reduces imposex development strongly in H. reticulata proves that the imposex-inducing effects of TBT are mediated by an increasing androgen level and are not caused directly by the organotin compound itself. Furthermore, TBT-induced imposex development can be suppressed in both snails by adding estrogens to the aqueous medium. These observations suggest that TBT causes an inhibition of the cytochrome P-450 dependent aromatase system which catalyses the aromatization of androgens to estrogens. The increase of the androgen content or the shift of the androgen-estrogen balance in favour of androgens induces the development of pseudohermaphroditism in marine prosobranchs. Artificial inhibition of the cytochrome P-450 dependent aromatase system using SH 489 (1-methyl-1,4-androstadiene-3,17-dione) as a steroidal aromatase inhibitor and flavone as a nonsteroidal aromatase inhibitor induces imposex development in N. lapfllus as well as in H. reticulata.

show abstract

Section: Resultsmentioning

confidence: 90%

TBT-induced imposex in marine neogastropods is mediated by an increasing androgen level

Bettin

Oehlmann

Stroben

1996

Helgolander Meeresunters

299

183

View full text Add to dashboard Cite

show abstract

“…Gibbs, Pascoe, and Burt (1988) reported that the imposex was induced in the dog-whelk Nucella lapillus at TBT concentrations below 2 ng l −1 and that 12 ng l −1 of TBT was sufficient to produce oviductal malformations. Lee (1986Lee ( , 1996 suggested that the susceptibility of mollusks to TBT may be connected to their low detoxifying activity due to low cytochrome P450 content and mixed function oxygenase activity that has been reported to play a role as a major function for TBT metabolism. Therefore, the TBT level in seawater in Maizuru Bay can still be considered to be toxic to susceptible organisms such as molluks, which might lead to disturbances in the dynamics of the population in the ecosystem.…”

Section: Comparison Of Contamination Level Of Ots Between Maizuru Baymentioning

confidence: 99%

Distribution and Fate of Organotin Compounds in Japanese Coastal Waters

Ohji

Arai

Midorikawa

et al. 2006

Water Air Soil Pollut

View full text Add to dashboard Cite

In order to elucidate the details of both the distribution and fate of organotin compounds (OTs) in the costal ecosystem, the concentrations of butyltin compounds (BTs) and phenyltin compounds (PTs) were determined in seawater, sediment and blue mussels Mytilus galloprovincialis collected in Maizuru Bay, Japan. The concentrations of tributyltin (TBT) in seawater, sediments and mussels ranged from 3.9 to 27 ng l −1 , from 1.2 to 19 ng g −1 dry wt and from 0.77 to 11 ng g −1 wet wt, respectively.Although the levels of TBT in seawater, sediments and mussels from Maizuru Bay were lower than those reported previously at other sites in Japan, the levels can still be toxic to susceptible organisms. Trace amounts of PTs were also found in seawater, sediment and mussel samples, indicating that there is a slight input of triphenyltin (TPT) into the seawater in the bay at present. The highest TBT concentration in seawater among all sites measured in the bay was found near a glass factory, and the lowest concentrations were observed at the center of the bay. The highest concentration of TBT in sediment was detected near a shipyard. In mussels, a high concentration of TBT was detected near a cement plant and timberyard. These results indicate that the major sources of contamination of OTs in the bay are considered to be from those facilities and ships. The proportion of TBT in seawater and mussels showed that, of total BTs, it was the predominant compound at most sites. These results suggested that there is a continuous input of TBT into the seawater and thereafter an accumulation of TBT in mussels due to their low metabolic capacity to degrade TBT. In sediment, the proportion of monobutyltin (MBT) was the highest of BTs at most sites. This could reflect a previous contamination by TBT used before the regulation of its usage in the bay.

show abstract

“…4E, F). This may be indicative of saturation of the tissues, although the presence of a much lower proportion of extractable tin in the TBT fraction (54+10% in males and 52 + 13% in females) may also reflect the induction of a process to counteract the accumulation of TBT by degrading it to DBT, and perhaps monobutyltin (Lee, 1986). It is conceivable that the degradation of the TBT tin occurs in the barnacles which are consumed, but would appear more likely that it is metabolised by JV.…”

Section: Tidal Tank Experiments (A) Accumulation Of Hexane-extractablmentioning

confidence: 99%

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

et al. 1987

View full text Add to dashboard Cite

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

show abstract

Metabolism of Bis(Tributyltin)Oxide by Estuarine Animals

Cited by 38 publications

References 14 publications

TBT-induced imposex in marine neogastropods is mediated by an increasing androgen level

TBT-induced imposex in marine neogastropods is mediated by an increasing androgen level

Distribution and Fate of Organotin Compounds in Japanese Coastal Waters

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

Contact Info

Product

Resources

About