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.     

Butyltin levels in several Portuguese coastal areas

This work aimed to report present levels (2007–2008 sampling) of tri- (TBT), di- (DBT), and monobutyltin (MBT) in surface sediments from 11 Portuguese coastal sites and discuss the evolution of BTs contamination in the last two decades. All the samples revealed quantifiable values of TBT, DBT, and MBT with total butyltin concentrations between 1 and 565 ng/g (of Sn in dry sediment). Maximum level of TBT, 66 ng/g, was observed in Sado estuary, at Lisnave site, in the proximity of a big shipyard. MBT decreased site by site by the same order as DBT and TBT did, but its concentrations were much higher in many cases, denoting that TBT contamination was much higher in the past. A comparison with the available previous data confirmed a marked decrease of TBT contamination all over the last years, indicating that the main sources of TBT in Portuguese coastwise stopped effectively.     

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.     

A new mussel certified reference material (CRM 477) for the quality control of butyltin determination in the marine environment

The analytical techniques used for the determination of butyltin compounds in biological tissues are generally based on a succession of steps (e.g., extraction, derivatization, separation, detection) which are all prone to systematic errors. An interlaboratory programme performed at the EU level and based on a stepwise approach has enabled one to identify and remove most of these errors and to improve considerably the state of the art so that certification of a mussel reference material has been made possible. This paper describes the preparation of this mussel reference material containing monobutyltin (MBT), dibutyltin (DBT) and tributyltin (TBT), the homogeneity and stability studies and the analytical work performed for the certification of the contents of MBT [Sn(C4H9)3+], DBT [Sn(C4H9)2(2+)] and TBT [Sn(C4H9)3+]. The results obtained by a group of expert EU laboratories are discussed along with the methods used to certify the mass fractions (based on dry mass) of monobutyltin (1.50 +/- 0.28 mg kg-1 as MBT cations), dibutyltin (1.54 +/- 0.12 mg kg-1 as DBT cations) and tributyltin (2.20 +/- 0.19 mg kg-1 as TBT cations). The paper also describes an attempt to certify the content of triphenyltin in this material which, although reasonable agreement was found among the participants' results, failed owing to the instability of this compound. This new material will be of great support to ensure the quality control of butyltin determination in shellfish, as carried out in environmental monitoring programmes.     

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.     

Persistent organic pollutants in Alaskan ringed seal (Phoca hispida) and walrus (Odobenus rosmarus) blubber

Since 1987, the Alaska Marine Mammal Tissue Archival Project (AMMTAP) has collected tissues from 18 marine mammal species. Specimens are archived in the National Institute of Standards and Technology's National Biomonitoring Specimen Bank (NIST-NBSB). AMMTAP has collected blubber, liver and/or kidney specimens from a number of ringed seals (Phoca hispida) from the areas near Nome and Barrow, Alaska and walruses (Odobenus rosmarus) from several locations in the Bering Sea. Thirty-three ringed seal and 15 walrus blubber samples from the NIST-NBSB were analyzed for persistent organic pollutants (POPs). The compounds determined included PCBs (28 congeners or congener groups), DDT and related compounds, hexachlorobenzene (HCB), hexachlorocyclohexane isomers (HCHs), chlordanes, dieldrin, and mirex. POP concentrations in ringed seal blubber were significantly higher in Barrow than in Nome when statistically accounting for the interaction of age and gender; HCB, however, was not statistically different between the two locations. Unlike males, POP concentrations and age were not significantly correlated in females probably as a result of lactational loss. POP concentrations in walrus blubber were lower than in ringed seal blubber for SigmaPCBs, chlordanes, and HCHs, but higher for dieldrin and mirex. POP concentrations in ringed seals and walrus from Alaska provide further evidence that the western Arctic tends to have lower or similar POP concentrations compared to the eastern Canadian Arctic.     

Fractionation of butyltin species during sample extraction and preparation for analysis

Solvent extraction and evaporative concentration steps are often used in procedures for the measurement of butyltins in environmental samples. As part of a larger study utilizing radiolabeled butyltins, the loss and fractionation of butyltins during sample preparation was investigated. TBT, DBT, and MBT were extracted from acidified seawater by hexane with efficiencies of about 95–99, 50–60 and 11% respectively. In addition, losses of about 70% of DBT were found during evaporative concentration of hexane. A variety of sediment extraction procedures were tested and none were found to be highly efficient for total butyltin extraction.     

Levels and temporal trends of HCH isomers in ringed seals from West and East Greenland

Levels and temporal trends of the hexachlorocyclohexane isomers alpha-, beta- and gamma-HCH were analysed in blubber of juvenile ringed seals from West Greenland (1994 to 2006) and juvenile and adult ringed seals from East Greenland (1986 to 2006). No significant differences in the concentration levels in the juvenile seals were found between East and West Greenland for any of the three isomers. alpha-HCH concentrations were not significantly different between juvenile and adult ringed seals from East Greenland, whereas beta- and gamma-HCH concentrations were significantly higher in adult ringed seals. alpha- and beta-HCH in Greenland ringed seals were approximately a factor two lower than in the Canadian Arctic, and alpha-HCH was a factor 2-3 higher than in ringed seals from an area east of Svalbard, Norway. Annual decreases in ringed seals from Greenland during the study periods were detected to be 9.1-11.7%, 1.4-3.9% and 6.0-6.4% for alpha-, beta- and gamma-HCH, respectively, being quite similar in both East and West Greenland. Similar levels and trends in East and West Greenland support the general understanding of the pathways of HCH isomers to and in the Arctic.     

Multivariate analysis of the bioaccumulation of polychlorinated biphenyls (PCBs) in the marine pelagic food web from the southern part of the Baltic Sea,Poland

The concentration, pattern, bioaccumulation and biomagnification features of many chlorobiphenyl congeners including non- and mono-ortho chlorine substituted members have been determined in a pelagic food chain including mixed phyto- and zooplankton, herring (Clupea harengus), harbour porpoise (Phocoena phocoena) and black cormorants (Phalacrocorax carbo sinensis) collected from the southern part of the Baltic Proper. TCDD (tetrachlorodibenzo-p-dioxin) toxic equivalents (TEQs) in plankton, herring, harbour porpoise and cormorants were 0.42, 5.3, 79 and 2,700 pg g(-1) lipid weight, respectively. Concentrations of total polychlorinated biphenyls (PCBs) in plankton, herring, harbour porpoise and cormorants were 1.9, 120, 8700 and 2,100 ng g(-1) wet weight (210, 1,300, 10,000 and 42,000 ng g(-1) lipid weight) respectively. Herring, harbour porpoise and black cormorant apparently bioaccumulate many PCBs found in their food, and the values of the bioaccumulation factors (BAFs) for PCBs were approximately 10 in herring, 35 in harbour porpoise and up to 300 in breast muscle of cormorants. Harbour porpoise clearly is able to metabolize the most toxic non-ortho PCBs (no. 77, 126 and 169) and a few mono-ortho PCBs (no. 114, 123 and 156), while all non- and mono-ortho PCBs are bioaccumulated by herring. Penta-, hexa- and hepta-CBs were the dominatant homologue classes both in the muscle tissue and liver. PCB congeners nos. 201, 209, 172/192, 194 and 195 were characterized by the largest BAFs (between 100 and 300). Principal component analysis has been used to analyse the interdependences and differences in the CB congener accumulation patterns between the components of the investigated pelagic food web.     

Bioaccumulation of Toxic Organic Compounds and Their Isomers into the Organism of Seals in West-Estonian Archipelago Biosphere Reserve

The Estonian coastal waters serve as the south-eastern boundary of the regular distribution of the grey (Halichoerus grypus and ringed Phoca hispida) seal in the Baltic Sea. During the annual molt period in May–June (in the Estonian coastal waters), the stock size is estimated to be 1200–1500 grey seal individuals – that is, roughly 25% of the whole Baltic population. If we compare the chlororganic contents of seals in different areas the Baltic Sea, we can see that the northern part of the Gulf of Riga and Väinameri Sea is the reference area of the Baltic Sea.     

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.     

Organotin compounds in a Norwegian fjord. A comparison of concentration levels in semipermeable membrane devices (SPMDs), blue mussels (Mytilus edulis) and water samples

Monitoring concentrations of organic pollutants in water is essential to predict effects and to initiate preventive steps. Results from the analysis of water samples provide snapshots of a situation, whereas monitoring using semipermeable membrane devices (SPMDs) provides a time-integrated picture of the concentration of pollutants in water. In this investigation, SPMDs, caged mussels and water samples were used to monitor the levels of organotin compounds in the inner Oslofjord, Norway, over a period of 12 weeks. The work-up procedure for the analysis of organotins was optimised, focusing on the clean-up procedure using gel permeation chromatography (GPC). By using several GPC columns, as much as 1 g of triolein could be employed. This reduces the background emission noise on the baseline, leading to an improvement in the detection limits. The main uptake of tributyltin (TBT) in mussels and SPMDs levelled off after 14 days. A longer uptake period was indicated for SPMDs at stations with a high water concentration of TBT (5-10 ng Sn L(-1)) compared with those with a low water concentration of TBT (approximately 1 ng Sn L(-1)). A concentration gradient was observed for water, SPMDs and mussels from the innermost station close to Oslo harbour to the station further out in the fjord, indicating that the three analysed matrices give approximately the same pollution gradient. The bioconcentration factor (BCF) for TBT in mussels was in the range 12-14 000 (wet weight) and, for SPMDs, 10-12 000 (fat). A good correlation with the TBT water concentrations was achieved within a period of 14-30 days of exposure for mussels and after 2-3 months for SPMDs. A good correlation was also found between the TBT concentration in SPMDs and mussels at the end of the experiment. SPMDs can therefore be used to predict concentrations of TBT in both water and mussels.     

Spatial and temporal distribution of butyltin compounds in a Northern Chesapeake Bay Marina and river system

This study was designed to: determine dibutyltin (DBT), tributyltin (TBT) and tetrabutyltin (TTBT) bi-weekly for a four month period (June-September 1986) in the Port Annapolis Marina, Mears Marina, Back Creek and Severn River area of Northern Chesapeake Bay; measure DBT, TBT and TTBT for five successive days (Thursday-Monday) to determine possible daily effects (weekday versus weekend) and determine DBT, TBT and TTBT every two hours for one full tidal cycle in the study area. Maximum concentrations of TBT were reported at both Port Annapolis Marina (1801 ng L^–1) and Mears Marina (1171 ng L^–1) during early June followed by significant reductions in TBT during late summer and early fall. All 4 Back Creek Stations also had highest concentrations of TBT in early June; significant reductions occurred during the next three months. The highest concentration of TBT reported in the Severn River (48 ng L^–1) occurred in September. The lowest TBT value (5 ng L^-1) at this station occurred in June. TTBT was not detected in any of the samples. The day of week sampled (Thursday-Monday) during the daily experiments was not found to significantly affect TBT concentrations. TBT evaluations every two hours during the tidal cycle demonstrated that values peaked at 1400 and 1600 hr time intervals. Peak concentrations of TBT occurred during a rising tide. The possible consequence of the measured TBT concentrations for aquatic biota are discussed.     

Monitoring of organotin compounds in seawater using semipermeable membrane devices (SPMDs)--tentative results

The impact of anthropogenic pollutants on the marine ecosystem is related to the concentrations experienced by the biota in the seawater and the resulting concentration in the organism. Results from monitoring of pollutants in water samples provide snapshots that can be high or low depending on a wide range of variables. To provide more integrated information, semipermeable membrane devices, SPMDs, have been used to monitor different organic pollutants. In this survey, SPMDs were used to monitor organotin compounds in the marine environment. Time-integrated sampling using SPMDs and direct water sampling was carried out at six stations in the inner Oslofjord, Norway. The sample work-up procedure for both water and SPMDs was based on direct derivatisation using NaBEt4 and simultaneous extraction with an organic solvent. Analysis was performed using a gas chromatograph equipped with an atomic emission detector. The results show that SPMDs do accumulate organotin compounds from the water phase. Both tributyl- (TBT) and dibutyltin were detected in all of the analysed membranes while no monobutyltin was found. Levels found in SPMDs range from < 1 to 220 ng Sn SPMD(-1). Water concentrations range from 0.4 to 10 ng Sn L(-1). An investigation of relative levels of TBT showed a similar concentration gradient in the inner Oslofjord using either direct water sampling or passive sampling by SPMDs. As the membranes are able to accumulate the organotins from the water it will be possible to locate lower concentrations than with direct analyses of water samples.     

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.     

Liquid chromatography-hydride generation-atomic absorption spectrometry for the speciation of tin in seafoods

Liquid chromatography with hydride generation atomic absorption spectrometry as the detection system was applied to the separation and determination of inorganic tin, tributyltin, dibutyltin, monobutyltin, diphenyltin and monophenyltin. A reversed phase C18 column and a methanol/water/acetic acid (70:27:3, v/v/v) mixture containing 0.05%(v/v) triethylamine and 0.1%(w/v) tropolone as the mobile phase (isocratic elution) were used. Extraction of organotins from the samples was carried out using methanol containing 0.05%(w/v) tropolone, a process that was repeated twice. The supernatants were shaken with water and dichloromethane in a separating funnel and the organic phase was collected and evaporated to dryness. When the method was applied to the speciation of tin in fresh and canned mussels, no organotins above the detection limits were identified in any of the samples, inorganic tin being the only species detected. The reliability of the procedure was checked by analyzing the total tin content of the samples by electrothermal atomic absorption spectrometry and by speciation of tin in a certified reference material, mussel tissue (CRM 477). The method can be used for environmental monitoring of organotins contaminated samples.     

Occurrence of organotins in the Yangtze River and the Jialing River in the urban section of Chongqing, China

The occurrence of organotins in the Yangtze River and the Jialing River in the urban section of Chongqing, China and their impact on drinking water waterworks are reported in this study. Water samples were extracted by solid-phase microextraction and measured using a gas chromatograph with mass spectrometer. The results showed that the rivers studied were polluted by both butyltins and phenyltins and that the butyltin species was the dominant pollutant. Butyltins, especially monobutyltin, were detected in all 18 sampling stations, and phenyltins were detected only in 11 sampling stations. Majority of the organotins were MBTs with concentrations varying from 27.3 to 1,145.8 ng Sn L^?1. Diphenyltin and dibutyltin were the second most common with the highest levels of 113.7 and 202.5 ng Sn L^?1, respectively. Monophenyltin, tributyltin, and triphenyltin had the lowest detection rates with concentration levels of 9.7, 161.8, and 37.2 ng Sn L^?1, respectively. Some of the organotins were also detected in drinking water waterworks, which posed a threat to the water quality of Chongqing.     

Exposure of Marine Mammals to Genotoxic Environmental Contaminants: Application of the 32P-Postlabeling Assay for Measuring DNA-Xenobiotic Adducts♯

There is little information on exposure of marine mammals to genotoxic environmental contaminants. The 32P-postlabeling assay has been successfully used to assess exposure to genotoxic polycyclic aromatic compounds in fish and humans. In the present study, a preliminary investigation showed that polycyclic aromatic compound-like DNA adducts were present in hepatic tissues of harbor seals (Phoca vitulina richardsi) exposed to petroleum following the Exxon Valdez oil spill. However, for marine mammals, effects from changes in tissue condition on DNA recovery and quality is of concern, because tissue samples are often collected from animals that have been dead for unknown periods of time. To assess the effects of postmortem thermal history on DNA recovery from tissue and on DNA adduct quantitation, samples of harbor porpoise (Phocoena phocoena) hepatic tissue were incubated for up to 10 d at 4 and 30 °C. Only traces (<4 g) of hepatic DNA were recovered from 200 mg of tissue after incubation at 30 °C for 36 h. At 4 °C, DNA (50–130 g) was recovered from tissue incubated for up to 6 d; whereas DNA recovery at 10 d was minimal. Chromatograms of 32P-labeled DNA digests of liver tissue held at 4 and 30 °C and salmon sperm DNA held at 30 °C for 2 d had comparable profiles, suggesting that alteration of DNA bases had occurred during incubation of porpoise liver tissue. Moreover, the chromatograms of DNA extracted from liver tissues of harbor porpoises caught incidentally in a northwest Atlantic fishery, packed in ice and sampled several days later also exhibited similar altered DNA structures. Although, altered DNA structures that can interfere with the DNA adduct quantitation were present in autolyzed tissue, changes in the 32P-postlabeling chromatography conditions can decrease the interference. Moreover, in a study with tissues taken from California sea lions (Zalophus californianus) immediately postmortem and stored at –80 °C until processing, DNA structures associated with tissue breakdown were not observed. The DNA from sea lions, however, had putative age-dependent hepatic DNA modifications, which have a distinctive profile, and must be considered when evaluating exposure of marine mammals to polycyclic aromatic compounds. Overall, the findings showed that with attention to the postmortem thermal history of the tissue samples hepatic DNA adducts, as measured by 32P-postlabeling, have the potential to serve as a biological indicator of exposure of marine mammals to environmental genotoxic compounds.     

Temporal trend studies on polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in ringed seals from east Greenland

The concentrations of polybrominated diphenyl ethers (PBDEs) 17, 28, 47, 49, 66, 85, 99, 100, 153, 154, and 183 were determined in ringed seal blubber from central East Greenland collected in 1986, 1994, 1999 and during the period 2001 to 2004. The trend of PBDEs was compared with the trends of polychlorinated biphenyls (PCBs) 28, 31, 52, 101, 105, 118, 138, 153, 156, and 180 during the same period. The levels of sigmaPBDE in East Greenland ringed seals ranged from 21.8 ng g(-1) lipid weight (1w) in 1986 to 39.3 ng g(-1) lw in 2001 and are among the highest observed in ringed seal from the Arctic. The dominating congeners were BDE-47 (75.4%) and BDE-99 (9.7%). The concentrations of PBDEs and PCBs increased with the age of the seals, and therefore only young seals < or =4 years old) were included in the temporal trend analyses. No significant trend (p > 0.14) was observed in sigmaPBDE or the congeners BDE 28, 47 and, 99 during the period while sigmaPCB decreased significantly (p = 0.004) over the period from 1986 to 2004 with an estimated annual rate of 4.3%.     

Butyltin Compounds in Sediments of the Bahía Blanca Estuary, Argentina

Systematic measurements of both Tributyltin (TBT) and Dibutyltin (DBT) in sediments along different locations in the inner zone of Bahía Blanca estuary were done. Two samples were taken near the main dry dock facility, at Puerto Belgrano naval base, in Argentina. TBT concentrations from non-detected to 170.3 ng Sn g⁻¹ were measured in the inner region of the estuary, and higher one of 3,288 ng Sn g⁻¹ near the dry dock at Puerto Belgrano. DBT values ranging between non-detected and 75.2 ng Sn g⁻¹ were obtained along the principal channel, but extreme concentration of 1,645 ng Sn g⁻¹ was measured at Puerto Belgrano. These values show that this estuary is affected by organotin pollution, mainly in areas of heavy shipyard activities.