Organotin contamination in South American coastal areas

Organotin compounds (OTs) were used in antifouling paints for more than four decades. However, due to their widespread intensive use and high toxicity, undesirable effects in non-target marine organisms have been detected since the early 1980s. Consequently, the International Maritime Organization banned new maritime applications of these products on January 1, 2003 and their presence on ship hulls from January 1, 2008. Although extensively studied in Europe, North America, Oceania, and Asia, environmental levels and effects of organotin contamination are still poorly known for South America. Thus, the current review aimed to present the actual status of this problem in South America by summarizing and comparing the available data in the literature. An overview of the OTs concentrations in sediment and biota and their effects, mainly imposex in marine gastropods, are presented. This work showed that in Atlantic coastal areas of South America there are “hot spots” of OTs contamination, similar to that observed in industrialized countries of Northern Hemisphere. On the other hand, the number of accomplished studies in the Pacific coast is extremely low. Despite the limitation on studies about OTs environmental levels and their related effects, the available data pointed out for a widespread TBT contamination along the South American coastal areas. Therefore, the establishment of baselines of organotin contamination in the Pacific coast and the implementation of temporal trend studies in the South American coastal areas is crucial to verify the effectiveness of local regulations and OTs global ban, and to map the most sensitive areas related to present and future antifouling impacts.     

A temporal and spatial monitoring of organotin pollution in a harborside region of Brazil by imposex and ecological quality ratio using <Emphasis Type="Italic">Leucozonia nassa</Emphasis>

This study represents the first use of Leucozonia nassa (Mollusca-Gastropoda) in a program of long-term monitoring. Specimens of L. nassa were collected between 2006 and 2014 and analyzed for the occurrence of imposex in two areas in Southeastern Brazil, one control area and another characterized by the presence of many ports and marinas. Imposex was evaluated in nine sites based on the percentage of females exhibiting imposex (I%), relative penis length index and vas deferens sequence index, classical indices to evaluate tributyltin (TBT) impacts. Moreover, this study uses for the first time in a tropical environment the ecological quality ratio (EQR), an approach to verify the imposex levels as an indicator of the impact by organotin compounds according to the EU Water Framework Directive. The results confirm the occurrence of high levels of imposex in L. nassa with all the indices evaluated. Furthermore, the results also indicate that, despite the international ban, antifouling paints based on TBT are still possibly used in Brazil. In addition, this study shows that L. nassa has the characteristics that make it a suitable bioindicator to monitor TBT pollution, and that the use of the EQR may create important data regarding this problem.     

Imposex and butyltin concentrations in Bolinus brandaris (Gastropoda: Muricidae) from the northern Tunisian coast

The imposex incidence and butyltin concentration i.e. tributyltin with its di- and mono-substituted metabolites were investigated in the muricid Bolinus brandaris sampled from two sites on the northern Tunisian coast (the Lagoon of Bizerta and the small Gulf of Tunis). Both populations had imposex, with stages of imposex development varying between VDS 1 and VDS 4.3. All imposex indices (imposex frequency (I %), female penis length, female vas deferens length, vas deferens sequence index, relative penis length index, and vas deferens length index) were significantly higher in snails from the Bizerta lagoon. Butyltins were detected in the whole tissues of both sexes from the two sites. TBT levels were higher in gastropods collected from the lagoon of Bizerta (12.65 ±1.48 ng Sn g^???1 dw in female and 15.21 ±1.13 ng Sn g^???1 dw in male) than in individuals from the Gulf of Tunis (10.71 ±1.26 ng Sn g^???1 dw in female and 11.65 ±1.63 ng Sn g^???1 dw in male), corroborating the data of imposex analysis. These results confirmed that B. brandaris could be used as a bioindicator species of butyltin pollution in the studied areas. In addition, this study provided baseline data that could serve for long-term monitoring of TBT pollution in Tunisia, since legislation to reduce the use of TBT-based antifouling paints has not been introduced yet.     

Depositional profiles and relationships between organotin compounds in freshwater and estuarine sediment cores

A range of organotin compounds including tributyltin (TBT), dibutyltin (DBT) and monobutyltin (MBT) were measured in sediment cores collected from contaminated freshwater and estuarine sites in Essex and Suffolk, U.K. Butyltin compounds were found in significant quantities at depths of up to 60 cm within the sediments of marina and boatyard complexes with TBT concentrations ranging from <3 ng g^–1 (the detection limit) to >3000 ng g^–1. In general sediment TBT concentrations decreased with depth, but maximum enrichment tended to occur just below the surface. It was evident from these core profiles that the accumulation of organotins in surface deposits was on the decline and coincided approximately, with the implementation in 1987 of the UK retail ban on the sale of TBT based antifouling paints for application on vessels <25 m in length. The degradation rate for TBT in sediments was found to exhibit first order kinetics with half lives ranging from 0.9–5.2 years between different sites. Estimated degradation rates have also been determined for DBT and MBT. These ranged from 1.5–3.0 years for DBT and 1.8–3.7 years for MBT.     

Spatial and temporal distribution of tributyltin (TBT) in seawater, sediments and bivalves from coastal areas of Korea during 2001–2005

Tributyltin (TBT) concentrations were determined in seawater, sediments and bivalve samples collected from Korean coastal areas during 2001-2005, to investigate the levels and temporal variation in TBT contamination in relation to the timing of the imposition of regulations on TBT use in Korea. TBT concentrations ranged from <5.0 to 164 ng/L in seawater, from <7.0 to 9,576 ng/g dry weight in sediments, and from <7.0 to 6,296 ng/g dry weight in bivalves. The highest concentrations of TBT were found at locations close to intensive shipping traffic and industrial complexes, and the contamination at some hot spot areas was high enough to cause harmful effects on marine organisms. TBT concentrations and their occurrence in Korean coastal waters have been decreasing annually. In particular, TBT concentrations in seawater have dramatically decreased. This result is consistent with regulations and bans on the use of TBT in Korea.     

Butyltin and copper monitoring in a Northern Chesapeake Bay marina and river system in 1989: An assessment of tributyltin legislation

This study was designed to: (1) evaluate dibutyltin (DBT) and tributyltin (TBT) bi-weekly in the water column for four months during the peak boating season (June–September, 1989) at seven stations in the Back Creek and Severn River area of Maryland waters of Chesapeake Bay; (2) compare butyltin values from the 1989 study with values obtained from a similar butyltin monitoring study conducted in 1988 (after Maryland TBT legislation) and 1986 (before Maryland TBT legislation); (3) determine the extent of TBT paint use in the Back Creek area by surveying boat owners; (4) determine dissolved copper concentrations from three of the seven stations bi-weekly during the four-month study; and (5) compare dissolved copper concentrations at these stations with previous copper data collected in 1988.Mean four-month DBT concentrations ranged from 10 to 73 ng/L at the seven stations. Highest DBT concentrations occurred at Station 1 in a marina; lowest concentrations occurred at Station 7 in the Severn River. Mean four-month TBT concentrations ranged from 177 ng/L at Station 1 (marina) to 21 ng/L at Station 7 (Severn River). Maximum TBT concentrations of 361 and 570 ng/L occurred at marina SDtations 1 and 3, respectively. Temporal trends in both DBT and TBT (station mean concentrations by date) showed that peak concentrations occurred during the early part of the boating season followed by reductions in late summer and early fall. Spike concentrations of both DBT (117 and 62 ng/L) and TBT (308 and 366 ng/L) were reported on two sampling dates near a boat maintenance facility in Back Creek.There was a significant reduction in DBT concentrations from 1986 to 1989 when date was treated as a fixed effect. However, TBT concentrations were not significantly reduced between 1986 and 1989 when mean concentrations of TBT were averaged across stations and dates for each year. A significant reduction was reported at Station 1 (marina station) when each station was examined for differences between years. TBT was also reported to significantly decrease (p=0.0442) at Station 7 between 1988 and 1989. A boat owner survey in the study area showed that 6% of the recreational boats that were surveyed were painted with TBT paint in 1989. This was a significant decrease in TBT paint use from the previous year when 31% of recreational boat owners surveyed used TBT paints.An evaluation of dissolved copper concentrations at three stations in the study area in 1989 showed that mean concentrations from bi-weekly sampling for four months was 10 g/L at Station 1, 7.8 g/L at Station 4 and 2.7 g/L at Station 7. Copper concentrations decreased with distance away from the Back Creek marinas. Copper concentrations at all three stations were significantly lower in 1989 than in 1988.     

An assessment of chemical contaminants in sediments from the St. Thomas East End Reserves,St. Thomas,USVI

The St. Thomas East End Reserves or STEER is located on the southeastern end of the island of St. Thomas, USVI. The STEER contains extensive mangroves and seagrass beds, along with coral reefs, lagoons, and cays. Within the watershed, however, are a large active landfill, numerous marinas, resorts, various commercial activities, an EPA Superfund Site, and residential areas, all of which have the potential to contribute pollutants to the STEER. As part of a project to develop an integrated assessment for the STEER, 185 chemical contaminants were analyzed in sediments from 24 sites. Higher levels of chemical contaminants were found in Mangrove Lagoon and Benner Bay in the western portion of the study area. The concentrations of polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT), zinc, copper, lead, and mercury were above a NOAA Effects Range-Low (ERL) sediment quality guideline at one or more sites, indicating impacts may be present in more sensitive species or life stages. Copper at one site in Benner Bay was above a NOAA Effects Range-Median (ERM) guideline indicating effects on benthic organisms were likely. The antifoulant boat hull ingredient tributyltin (TBT) was found at the third highest concentration in the history of NOAA’s National Status and Trends (NS&T) Program, which monitors the nation’s coastal and estuarine waters for chemical contaminants and bioeffects. The results from this project will provide resource managers with key information needed to make effective decisions affecting coral reef ecosystem health and gauge the efficacy of restoration activities.     

Shell disturbances and butyltins burden in commercial bivalves collected from the Bizerta lagoon (northern Tunisia)

Shell disturbances and soft tissues butyltin burden were investigated in commercial bivalves Lithophaga lithophaga, Mytilus galloprovincialis, Solen marginatus and Crassostrea gigas from the Bizerta lagoon. Shell disturbances were found in all bivalves, being scarce in S. marginatus. In the internal valve of L. lithophaga, burrowing annelids and sipunculids living inside galleries were observed, while in the external valve, brown-blackish or white stains were found. In M. galloprovincialis, a yellowish mass located at the shell anterior side was found fixed firmly to the pearly layer by a hard brownish structure covering some annelid elliptic eggs. In the internal shell layer of some specimens collected in April, embryos belonging to tubiculous annelids at various developmental stages were observed. In C. gigas, shell thickening was revealed in some specimens corresponding to white doughy deposits at the internal valve and between shell layers. In S. marginatus, only one specimen showing a cavity at the posterior site was found. Total butyltin concentrations in the studied bivalves varied between 30 and 245?ng/g dry weight with tributyltin (TBT) being the predominant compound. The highest concentration was recorded in L. lithophaga collected from the Bizerta Bay and the lowest concentration in S. marginatus from Maghraoua. This study provided baseline data that could serve for long-term monitoring of TBT pollution in Tunisia, since legislation to reduce the use of TBT-based antifouling paints has not been introduced yet.     

Time trend of Butyl- and Phenyl-Tin contamination in organisms of the Lagoon of Venice (1999–2003)

In the period 1999-2003 a monitoring study on the accumulation of organotin compounds in edible organisms in the Lagoon of Venice was conducted. Butyl and Phenyl derivatives were determined in pooled samples of Mytilus galloprovincialis and Tapes spp. with the aims of assessing organotin contamination in the Lagoon of Venice in the period just preceding their ban in Europe, monitoring the concentrations in organisms with a high commercial use, evaluating a potential hazard for human health due to seafood and identifying the possible contamination sources. Sampling stations (up to 20) were distributed around the Lagoon and particularly concentrated in the area close to the town of Chioggia. Significantly higher (analysis of variance (ANOVA), p < 0.05) tributyltin (TBT) concentrations were found in mussels (from 38 +/- 8 to 6,666 +/- 1,333 microg kg(-1) d.w., as TBT(+)), than in clams (from 6 +/- 1 to 2,256 +/- 451 microg kg(-1) d.w., as TBT(+)). During the 3 years of the survey no increase in average concentrations of the butyltin compounds (tributyltin (TBT) + dibutyltin (DBT) + monobutyltin (MBT)) was observed (ANOVA, p > 0.05) in either species. Furthermore, by analyzing the entire data set, it is evident that most stations show analogous concentrations in the 3 years for both species, whereas few have anomalously higher concentrations. If organotin concentrations in specimens from some sites are compared with the Tolerable Average Residue Level, a possible risk for human health must be considered.     

The effects of organotin on female gastropods

Female masculinisation (FM) in gastropods (imposex, intersex and ovo-testis) has been documented in > 260 species globally. Biomonitoring studies use FM to indirectly assess the presence of tributyltin (TBT), a once popular biocide in antifouling paint, which has since been regulated. Laboratory studies confirm that FM in gastropods can be induced not only by TBT, but other tin (Sn) compounds, Sn "cocktails", steroids, and other contaminants such as Aroclor 1260. Even though FM in gastropods in the field has been attributed to TBT from boating activity, there is evidence that imposex occurred prior to the advent use of TBT in the 1960s, and for some species imposex occurs naturally. There are roughly 42 species that do not elicit a FM response even if they are exposed to TBT under laboratory conditions, collected sympatrically with other species displaying FM, and/or have TBT in their tissues. A geographic analysis of field studies in four regions indicates that the bulk of studies were conducted in Europe > Asia and Oceania > North America > Latin America. More data are needed regarding FM in Africa, the Middle East, and Latin America since data regarding the masculinisation of female gastropods in these areas are lacking. The most studied gastropod species used in TBT biomonitoring studies is the dogwhelk, Nucella lapillus. This review summarizes the progression of the literature from 1962 to 2009 outlining how the terminology, science, and theories have evolved over time.     

Butyltin contamination in sediments and seawater from Kaohsiung Harbor, Taiwan

The distribution of butyltin (BT) compounds in the sediments and seawater, at the river outfalls, fishing ports, shipyards, and industrial zone docks of Kaohsiung Harbor, Taiwan were investigated. Twenty sediment and seawater samples were collected from various locations in the Harbor in 2006 and analyzed for monobutyltin (MBT), dibutyltin (DBT), and tributyltin (TBT). Results showed that the concentration of total BTs varied from 1.5 to 151 ng/g in sediment samples, with TBT being the major component of the sediment samples. This suggests that sediments could be the most possible sink of TBT brought by the sorption mechanism. The concentrations of BTs ranged from 9.7 to 270 ng/L in seawater samples, whereas DBT and MBT, the degradation byproducts of TBT, were mainly the most abundant BT compounds of the seawater samples. This indicates that the abiotic or biotic degradation potential of TBT was significant. Spatially, the highest concentrations of BTs were observed in both water and sediment samples collected from the shipyard and fishing port areas. This indicates that the shipping-related activities (e.g., navigation, ship repair, and ship building) would contribute most of BTs in the environment. Results show that the concentrations of degradation products (DBT and MBT) were related closely to temperature, salinity, dissolved oxygen (DO), and chlorophyll-a of the seawater. This implies that seasonal changes of the water parameters controlled the degradation of TBT in seawater. The observed levels of BT compounds in both seawater and sediments were much higher than those required to induce toxic effects on marine organisms, suggesting that appropriate TBT control strategies should be taken in Kaohsiung Harbor.     

Organotins in marine mammals and seabirds from Norwegian territory

An increasing number of studies indicate that marine mammals and some seabirds are exposed to organotins. However, results from northern and Arctic areas are few. Here results from analysis of tributyltin (TBT), dibutyltin (DBT), monobutyltin (MBT), triphenyltin (TPhT), diphenyltin (DPhT) and monophenyltin (MPhT) in harbour porpoise (Phocoena phocoena), common seal (Phoca vitulina), ringed seal (Phoca hispida) and glaucous gull (Larus hyperboreus) from Norwegian territory are presented. Relatively high concentrations of DBT, TBT and MBT were observed in muscle, kidney and liver from harbour porpoises caught in northern Norway in 1988, just before restrictions on the use of tributyltin (TBT)(mainly on small boats) were introduced in several European countries. The concentrations in harbour porpoise muscle tissue were reduced significantly 11 years later, possibly as a result of the introduced restrictions. Considerably lower concentrations of butyltins were observed in the seals compared to porpoises. The lowest levels of organotins were found in ringed seals from Spitsbergen, where only traces of dibutyltin (DBT) and monobutyltin (MBT) were observed. Traces of DBT and MBT were also found in some individual glaucous gulls from Bear Island. The sum of the degradation products MBT and DBT in liver samples from all analysed species were generally higher than TBT itself. Triphenyltin (TPhT) was observed in all porpoise samples and in livers of common seals. Also the sum of the degradation products MPhT and DPhT in liver samples from porpoise and common seals were higher than TPhT. No traces of phenyltins were found in ringed seals from Spitsbergen or in glaucous gulls from Bear Island. The limited data available indicate low to moderate exposure to organotins in northern areas (Spitsbergen and Bear Island). Marine mammals are however more exposed further south along the Norwegian Coast.     

Organotin compounds in the marine environment of the Bay of Piran,northern Adriatic Sea

In the year 2000, organotin pollution was investigated in the Bay of Piran, Slovenia, at the northern extremity of the Adriatic Sea. Gas chromatography-mass spectrometry with single ion monitoring GC/MS-SIM was applied for speciation analysis of pentylated organotin compounds in water and mussels. Sampling of marine waters was performed in summer and autumn at 8 locations. Mussels Mytilus galloprovincialis were collected only in summer at 3 locations. The highest concentrations of tributyltin (TBT) in marine water ranged from 500 to 630 ng L(-1) (as Sn) in summer and from 180 to 230 ng L(-1) (as Sn) in autumn. TBT concentration in mussels varied from 500 to 3500 ng g(-1) dry weight (d.w.) (as Sn). The study indicated remarkable butyltin pollution of the Slovenian coastline. Accuracy of the analytical procedure was verified by BCR CRM 477.     

Butyltin compounds and their relation with organic matter in marine sediments from San Vicente Bay—Chile

Tributyltin and its degradation products, mono-and dibutyltin have been determined in sediments collected in some representative sites in San Vicente Bay, Chile. The organic matter contents of sediments and water collected simultaneously from the same sampling sites were also determined. High levels of total organic carbon were found in sediments, especially in those from the northern part of the bay (1.80-8.87%). Good correlations were found between total organic carbon and the oxidizable and refractory carbon fractions. Among the butyltin species determined, TBT presented the highest levels, ranging from 14 to 1,560 ng Sn g(-1) dry weight. Concentration ratios of TBT to DBT ranged between 1.33 and 3.10, showing a high degree of contamination in sediments of this Chilean bay. All data obtained were analysed by the chemometric method of principal components analysis. A strong correlation was found between TBT and DBT concentrations in sediments, the different organic matter contents in sediments and water. In marine organisms only TBT was detected, containing the filterer organism Semele solida higher level than Perumytilus purpuratus and Pyura chilensis (220, 150 and 120 ng Sn g(-1) dry weight, respectively). For the alga Rodoficea iridae the TBT concentration was 60 ng Sn g(-1) dw. Comparatively, these values are higher than those reported for the same kind of marine organisms worldwide. The different samples from San Vicente Bay were found to be contaminated by TBT. This contamination can be attributed to the different anthropogenic activities taking place in the bay.     

Sub-Surface Investigations on Deep Saline Groundwater of Charnockite Rock Formation, Kalpakkam, India

Investigations on geohydrological aspects of coastal aquifer are important in order to understand the mechanism of ground water salinisation. The present study describes the salinity variations of ground water in deep boreholes drilled in Charnockite rock formation of Kalpakkam, on the eastern coast of India. Water samples collected up to 600m depth were analyzed for salinity variation. It is noticed that in one of the boreholes, (borehole K1), the salinity level is found to be 74 parts per thousand (ppt) at 400 m depth. Influence of surface saline water bodies viz., sea (26-28.5 ppt), backwaters (27-30 pt) and Buckingham canal (27-32 ppt) as the possible sources of recharge of fresh waters through joint and fracture system of the rock are discussed in this paper. Studies would assist in understanding the geohydrological characteristics of deep geological formation.     

Macrofaunal recovery following TBT ban

In the United Kingdom, the use of TBT-based anti-fouling paints on small vessels was banned in 1987, and a biological study of the Crouch Estuary, a yachting centre on the south-eastern coast of the UK, was conducted in order to determine the ecological improvements resulting from this legislation. We present the changes in the macro-infaunal communities along the estuary in relation to declining TBT concentrations between 1987 and 2005. Although the major changes in response to the ban were observed within the first 3 years (primarily an increase in the number of crustacean taxa and a shift in community structure), with changes still apparent between three and 5 years, the temporal duration of this study allowed the rapidity of the response to be truly determined.     

Survey of four marine antifoulant constituents (copper,zinc, diuron and Irgarol 1051) in two UK estuaries

A field survey of antifoulant concentrations was undertaken in two UK estuaries (Hamble and Orwell) in 1998 and 1999. The two locations offered variations in physical aspects (Orwell estuary being significantly larger than the Hamble) as well as differences in boat densities (Hamble having almost twice as many vessels moored in the estuary and marinas). Samples were analysed for copper, zinc, diuron and Irgarol 1051, and were collected in summer and winter in order to identify potential seasonal variations in concentrations. The effect that different marina types (e.g. locked marina, one located in a natural inlet and pontooned ones in the open estuary) had on antifoulant concentrations were also investigated. Concentrations of the organic booster biocides, diuron and Irgarol 1051 in the marinas and estuaries were mainly influenced by leaching from antifoulant paints applied to the hulls of leisure craft, and so levels reflected the number of vessels present in the water. As a consequence significantly higher concentrations were found in marinas (up to ca. 900 ng l(-1) for diuron and 240 ng l(-1) for Irgarol 1051) compared with estuaries (up to ca. 400 ng l(-1) for diuron and 100 ng l(-1) for Irgarol 1051) and in summer compared with winter. Sediment concentrations of Irgarol 1051 and diuron were rarely detectable other than in the marinas where high concentrations were detected near slipways assumed to be derived from washed off paint chips. Dissolved concentration profiles for copper and zinc in the estuaries and marinas were different from those for the organic booster biocides partly because other sources of these metals contributed to estuarine and marina loads. In particular, riverine loads and inputs from sacrificial anodes attached to leisure craft, exhibited a major influence of estuarine levels of zinc. Consequently, only in the Hamble estuary for copper was there a clear distinction between summer (typically 3-4 microg l(-1)) and winter dissolved values (typically 1-2 microg l(-1)) that could be largely attributable to the leaching of antifoulant paints. Sediment concentrations for both metals were similar for both estuaries, with little variation between winter and summer values (Zn ranging from 28 to 614 mg kg(-1) and Cu from 6 to 1016 mg kg(-1)) as with the organic booster biocides highest levels were measured at the base of slipways in marinas.     

Organotins in a medium-size Mediterranean basin (the Herault River)

This study reports the first assessment of organotin pollution in the Hérault watershed, a medium size Mediterranean basin. Organotin compounds were analyzed in surface waters, wells supplying drinking water and sewage treatment plants (STPs). In surface and ground waters, a background contamination by total organotin compounds has been identified in the range of 0.51 +/- 0.02-71 +/- 2 ng(Sn) L(-1), which is of the same order of magnitude as those observed in other European areas. Organotins were systematically present in STP influents and sludge. Total or partial elimination of organotin compounds from treated wastewater was observed. STP effluents appeared nevertheless to be a non-negligible source of contamination not only of rivers but also of aquifers tapped for drinking water supply.Tributyltin concentration was higher than the maximum allowable concentration proposed by the European Commission in some surface waters and wells supplying drinking water. This could compromise the water resource and have serious and irreversible consequences for the aquatic eco-system. As it was the case for the ban of antifouling paints, a regulatory regime in decreasing point-source emissions of these harmful compounds used in household products might be applied.     

Organotin compounds in surface sediments from seaports on the Gulf of Gda??sk (southern Baltic coast)

Sediment samples were collected in two Polish ports of international significance--the Port of Gdańsk and the Port of Gdynia (Gulf of Gdańsk, Baltic Sea)--in order to assess their butyltin and phenyltin contamination; this was done in 2008, just after the total ban on using harmful organotins in antifouling paints on ships came into force. Altogether, 21 sampling stations were chosen to present a diversity of port sites: from port canals and shipyards to anchorages and dumping sites. The organic carbon content and grain size of all the sediment samples were determined, and some environmental parameters (oxygen content, salinity) were measured as well. Total concentrations of butyltin compounds in sediment samples were very different and ranged between 1 and 18,520 ng Sn g(-1) d.w. Phenyltin contents were distinctly lower and ranged from below the limit of detection (most samples) to 660 ng Sn g(-1) d.w. The highest concentrations of organotins were found in the shipyards, the maximum total organotin content (19,180 ng Sn g(-1) d.w.) being found in the Gdańsk Ship Repair Yard 'Remontowa'. Butyltin degradation indices indicate a recent tributyltin input into the port sediments. The results obtained from this work prove that the international ban on using organotins may not be enough to protect the marine environment. It is necessary to monitor organotin contamination in ports and establish concentration limits of these compounds for the disposal of dredged material at sea.     

A field evaluation of international monitoring guidelines for the biological effects of tributyltin

The Oslo and Paris Commission (OSPAR) Guidelines for monitoring the biological effects of tributyltin compounds (TBT) were evaluated using data collected for preparation of a Celtic Seas Quality Status Report. Two types of survey were undertaken: broad scale, to determine wide impacts in coastal waters; and localised, around representative harbours to establish ranges of effect from recognised input points. This evaluation indicates that results from the broad scale surveys can be used to compare different areas of coastline. Nucella is widespread away from point sources although many individuals show some degree of imposex. Populations are generally not at risk. The localised surveys indicate that, in certain situations, the monitoring objectives can be met in the OSPAR Guidelines (subject to minor amendment). Criteria are identified for the selection of point sources suitable for monitoring under OSPAR Guidelines.