Ubiquitous imposex and organotin bioaccumulation in gastropods Nucella lapillus from Galicia (NW Spain):a possible effect of nearshore shipping

Abstract

A survey was conducted during the summer of 1996 to assess the expression, extent and impact of hnposex (a set of sexual anomalies) in 37 populations of Nucella lapillusspread over the Galician coastline (NW Spain); the bioaccumulation of several organotin (OT) species (monobutyltin. MBT; dibutyltin, DBT; tributyltin, TBT; and triphenyltin, TPhT) was also determined in 20 of those samples. While imposex, TBT (from 36 to 974 ng Sn g-' dry weight, ppb) and DBT (from 169 to 909 ppb) were detected in every sample examined, MBT (from 65 to 387 ppb) and TPhT (from 39 to 250 ppb) were quantifiable in only 15 and 11 of them, respectively. lmposex was found to have led to frequent female sterilisation in most of the populations of this intertidal gastropod, although none of them is considered to be at risk of extinction. This may be partially due to the observation that these specimens appear more resistant to the sterilising effect of TBT than northern congeners. Fishing and merchant fleets are thought to be the dominant sources of OT pollution within embayments, with pleasure boats being of lesser importance. In addition, the characteristic pattern of OT body residues [i.e. undetectable TPhT and low TBT/(TBT+DBT) ratio] indicates that imposex in several open coast populations may stem from nearshore merchant shipping via the horizontal transport of paint leachates.

Occurrence of imposex in Thais haemastoma: possible evidence of environmental contamination derived from organotin compounds in Rio de Janeiro and Fortaleza, Brazil

“…In South America, imposex occurrence is reported in Chile (Chorus giganteus, Xanthochorus cassidiformis, Nucella crassilabrum - Gooding et al, 1999) and Brazil (Castro et al, 2000;Fernandez et al, 1998;Magalhães et al, 1997). Information on concentration in waters (Hashimoto et al, 1998; Malaca straits), sediments (Kan-Atireklap et al, 1997a -Thailand;Ko et al, 1995 -Hong Kong;Stewart & de Mora, 1992 -Fiji Island;King et al, 1989 -New Zealand) and organisms (bivalves, Perna viridis -Kan-Atireklap et al, 1997b; Mytidus edulis and Aequipecten irradians - Guolan & Yong, 1995;gastropods, T. clavigera, Thais tuberosa and Morula granulataLiu et al, 1997) are scarce, although reported levels specially in areas including intensive navigation and harbor installations have been high (over 1,000ng.g -1 ) and of the same order as those available for temperate climate areas (Morgan et al, 1998;Ruiz et al, 1998;Swennen et al, 1997;ten Hallers-Tjabbes et al, 1994). As for the effect on humans, although organotin compounds are considered extremely toxic, environmental routes of exposure are usually not considered very critical (Schweinfurth & Günzel, 1987;Tsuda et al, 1995).…”

Imposex in Nucella lapillus: a ten year survey in NW Brittany

“…Similar improvements of imposex condition have been reported in other areas where legislative bans of TBT were effective, such as in the North Sea (Evans et al 1991, 1996, Harding et al 1997, Birchenough et al 2002a), SW England (Bryan et al 1993), Ireland (Minchin et al 1995), Australia (Rees et al 2001) and Canada (Reitsema et al 2002). Despite the same legislative ban of TBT, a reverse trend has been observed in Spain (Ruiz et al 1998, Ramon & Amor 2001 and in Portugal (Barroso & Moreira 2002, Santos et al 2002. In Thailand, where no restriction of TBT use has been introduced, imposex has increased (Bech 2002).…”

“…Those females that were still fertile had probably not spent enough time at this location to undergo sex-change (with spermiogenesis in the gonad) or sterilisation. Similar levels of TBT pollution (high enough to prevent the maintenance of N. lapillus populations) have been reported in Scotland (Harding et al 1997), Ireland (Minchin et al 1997), Spain (Ruiz et al 1998), Norway (Følsvik et al 1999), and Portugal (Barroso & Moreira 2002).…”

Biomonitoring organotin pollution with gastropods and mussels

“…However, Fig. 3 indicates that even if there is some input seasonality (probably not widespread because pleasure boating is not popular in the region, see Ruiz et al 1998), it is overcome by the combined use of biomonitors which, by definition, are time-integrators of ambient pollutants. The second obstacle stems from the contrast between the ecology of the mussel (a rocky bottom filter feeder) and the gastropod (a sediment-dwelling detritivore), a disparity that leads to the presumption of different routes of uptake and diverging OT tissue loads.…”

“…There, TBT in Nucella lapillus in 1996 (see Ruiz et al 1998) reached 974 ppb Sn DW, with ΣBTs proportions at 54% (TBT), 36% (DBT) and 10% (MBT). In the present work, mussels (the favourite prey of N. lapillus) at Site 11 show the same decreasing order for ΣBTs proportions, absolute N. lapillus values in summer 1996 doubling those for mussels in autumn 2000 .…”