Speciation without chromatography: Part I. Determination of tributyltin in aqueous samples by chloride generation, headspace solid-phase microextraction and inductively coupled plasma time of flight mass spectrometry

An analytical procedure was developed for the determination of tributyltin in aqueous samples. The relatively high volatility of the organometal halide species confers suitability for their headspace sampling from the vapour phase above natural waters or leached solid samples. Tributyltin was collected from the sample headspace above various chloride-containing matrices, including HCl, sodium chloride solution and sea-water, by passive sampling using a polydimethylsiloxane/divinylbenzene (PDMS/DVB)-coated solid-phase microextraction (SPME) fiber. Inductively coupled plasma time-of-flight mass spectrometry (ICP-TOFMS) was used for detection following thermal desorption of analytes from the fiber. A detection limit of 5.8 pg ml–1(as tin) was realized in aqueous samples. Method validation was achieved using NRCC PACS-2 (Sediment) certified reference material, for which reasonable agreement between certified and measured values for tributyltin content was obtained

Isolation of tributyltin-degrading bacteria citrobacter braakii and enterobacter cloacae from butyltin-polluted sediment

Tributyltin compound (TBT) released into the aquatic environment is generally degraded by bacteria in water and sediment. The isolation of TBT-degrading bacteria from TBT polluted sediment leads to the indication of specific potential TBT degraders. Two new strains of bacteria designated as B2 and B3 were successfully isolated using glycerol medium containing tributyltin chloride (TBTC) at 130 μM from contaminated sediment collected from Bowling Basin in Glasgow. The observed degradation after 14 days of the microcosm from the sediment and the isolated bacteria were investigated at an initial concentration of 1 μM TBTC. It was found that TBT was degraded by the bacterial strains B2 and B3 at 8.3 and 16.9 %, respectively. The results indicate that B2 and B3 are effective as TBT degraders. EC50 of B2 and B3 in water were 88.73 and 112.53 μM TBTC, which were significantly higher than the concentration of TBT measured at the basin, suggesting a low effect of TBT on the growth and activity of bacteria. After identification using API 20E and 16S sequencing, the bacterial isolate strain B2 is Citrobacter braakii and B3 is Enterobacter cloacae. Therefore, this study has discovered two species of high resistance TBT degrader which have never been previously studied or isolated based upon TBT degradation ability

Removal processes for tributyltin during municipal wastewater treatment

This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2013 Springer.The fate and behaviour of tributyltin (TBT) at two wastewater treatment works was examined. Both sites had two inlet streams, and each utilised high rate biological filters (biofilters) on one the streams, before treatment of the combined flows on trickling filters, with one having additional tertiary processes, installed to remove ammonia and solids. The study was designed to determine if these processes enhanced the removal of TBT. Degradation of TBT was observed in one of the biofilters, possibly as a result of temperature and hydraulic loading. At the treatment works with tertiary processes, the mass flux showed the overall removal of TBT was 68 %, predominantly due to removal with solids in the primary settlement processes. However, overall removal of 95 % was observed in the conventional trickling filter works with 94 % of this due to biodegradation in the trickling filter. The two works both removed TBT, but at different treatment stages and by different processes. Differences in the form (solubility) of TBT in the influent may have attributed to this, although further understanding of factors controlling degradation would allow for a more complete assessment of the potential of biological processes to remove hazardous compounds from wastewaters.United Utilities PL

Butyltin compounds in a sediment core from the old Tilbury basin, London, UK

Sections from a sediment core taken from the River Thames were analysed for butyltin species using gas chromatography with species-specific isotope dilution mass spectrometry. Results demonstrated that in most samples tributyltin concentrations of 20–60 ng/g accounted for <10% of the total butyltin species present, which is in agreement with data from other sediment samples which were historically contaminated with tributyltin. Vertical distribution of the organotin residues with depth throughout the core, with data on organochlorine compounds and heavy metals allowed for the construction of a consistent hypothesis on historical deposition of contaminated sediments. From this it was possible to infer that the concentrations of tributyltin in sediments deposited during the early 1960s were in the order of 400–600 lg/g by using degradation rate constants derived by other workers. Such values fall well within the range quoted for harbour sediments in the literature

Is There a Causal Association between Genotoxicity and the Imposex Effect?

There is a growing body of evidence that indicates common environmental pollutants are capable of disrupting reproductive and developmental processes by interfering with the actions of endogenous hormones. Many reports of endocrine disruption describe changes in the normal development of organs and tissues that are consistent with genetic damage, and recent studies confirm that many chemicals classified to have hormone-modulating effects also possess carcinogenic and mutagenic potential. To date, however, there have been no conclusive examples linking genetic damage with perturbation of endocrine function and adverse effects in vivo. Here, we provide the first evidence of DNA damage associated with the development of imposex (the masculinization of female gastropods considered to be the result of alterations to endocrine-mediated pathways) in the dog-whelk Nucella lapillus. Animals (n = 257) that displayed various stages of tributyltin (TBT)-induced imposex were collected from sites in southwest England, and their imposex status was determined by physical examination. Linear regression analysis revealed a very strong relationship (correlation coefficient of 0.935, p < 0.0001) between the degree of imposex and the extent of DNA damage (micronucleus formation) in hemocytes. Moreover, histological examination of a larger number of dog-whelks collected from sites throughout Europe confirmed the presence of hyperplastic growths, primarily on the vas deferens and penis in both TBT-exposed male snails and in females that exhibited imposex. A strong association was found between TBT body burden and the prevalence of abnormal growths, thereby providing compelling evidence to support the hypothesis that environmental chemicals that affect reproductive processes do so partly through DNA damage pathways

Seafood from Norway : food safety

Since Norway is a major supplier of seafood worldwide, monitoring the food safety of Norwegian fish products is a priority. This commentary gives a brief overview of the food safety of seafood from Norwegian waters. Several preventative measures during harvest/catch, processing and distribution have been established and are implemented regularly. Furthermore, comprehensive monitoring programmes to detect and quantify undesirable substances, such as heavy metals and polychlorinated biphenyls (PCBs), in Norwegian seafood are carried out. Substances with health benefits, such as omega-3 fatty acids, are also analysed. In general, evidence shows the level of undesirable substances in seafood from Norway to be low. In fact, in the majority of samples analysed, levels of undesirable substances were reported to be below the maximum limit set by the European Union (EU). This leads to the conclusion that consumption of seafood originating from Norway involves a low risk of negative health effects and that consumers can have confidence in the products they purchase.peer-reviewe

Intracellular Chloride Concentration Changes Modulate IL-1β Expression and Secretion in Human Bronchial Epithelial Cultured Cells

Cystic fibrosis (CF) is caused by mutations in the CFTR gene, which encodes a cAMP‐regulated chloride channel. Several cellular functions are altered in CF cells. However, it is not clear how the CFTR failure induces those alterations. We have found previously several genes differentially expressed in CF cells, including c‐Src, MUC1, MTND4, and CISD1 (CFTR‐dependent genes). Recently, we also reported the existence of several chloride‐dependent genes, among them GLRX5 and RPS27. Here, varying the intracellular chloride concentration [Cl−]i of IB3‐1 CF bronchial epithelial cells, we show that IL‐1β mRNA expression and secretion are also under Cl− modulation. The response to Cl− is biphasic, with maximal effects at 75 mM Cl−. The regulation of the IL‐1β mRNA expression involves an IL‐1β autocrine effect, since in the presence of the IL‐1β receptor antagonist IL1RN or anti‐IL‐1β blocking antibody, the mRNA response to Cl− disappeared. Similar effects were obtained with the JNK inhibitor SP600125, the c‐Src inhibitor PP2 and the IKK inhibitor III (BMS‐345541). On the other hand, the IL‐1β secretion is still modulated by Cl− in the presence of IL‐1RN, IL‐1β blocking antibody, or cycloheximide, suggesting that Cl− is affecting the IL‐1β maturation/secretion, which in turn starts an autocrine positive feedback loop. In conclusion, the Cl− anion acts as a second messenger for CFTR, modulating the IL‐1β maturation/secretion. The results also imply that, depending on its intracellular concentration, Cl− could be a pro‐inflammatory mediator.Fil: Clauzure, Mariangeles. Pontificia Universidad Católica Argentina "Santa María de los Buenos Aires". Instituto de Investigaciones Biomédicas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; ArgentinaFil: Valdivieso, Ángel Gabriel. Pontificia Universidad Católica Argentina "Santa María de los Buenos Aires". Instituto de Investigaciones Biomédicas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; ArgentinaFil: Massip Copiz, María Macarena. Pontificia Universidad Católica Argentina "Santa María de los Buenos Aires". Instituto de Investigaciones Biomédicas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; ArgentinaFil: Mori, Consuelo. Pontificia Universidad Católica Argentina "Santa María de los Buenos Aires". Instituto de Investigaciones Biomédicas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; ArgentinaFil: Dugour, Andrea Vanesa. Fundación Pablo Cassara; ArgentinaFil: Figueroa, Juan Manuel. Fundación Pablo Cassara; ArgentinaFil: Santa Coloma, Tomás Antonio. Pontificia Universidad Católica Argentina "Santa María de los Buenos Aires". Instituto de Investigaciones Biomédicas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; Argentin

The ecological impact of different mechanisms of chronic sub-lethal toxicity on feeding and respiratory physiology

Sub-lethal toxicity tests, such as the scope-for-growth test, reveal simple relationships between measures of contaminant concentration and effect on respiratory and feeding physiology. Simple models are presented to investigate the potential impact of different mechanisms of chronic sub-lethal toxicity on these physiological processes. Since environmental quality is variable, even in unimpacted environments, toxicants may have differentially greater impacts in poor compared to higher quality environments. The models illustrate the implications of different degrees and mechanisms of toxicity in response to variability in the quality of the feeding environment, and variability in standard metabolic rate. The models suggest that the relationships between measured degrees of toxic stress, and the maintenance ration required to maintain zero scope-for-growth, may be highly nonlinear. In addition it may be possible to define critical levels of sub-lethal toxic effect above which no environment is of sufficient quality to permit prolonged survival

Toward a Global Regime of Vessel Anti-Fouling

Vessel anti-fouling is key to the efficient operation of ships, and essential for effective control of invasive species introduced through international shipping. Anti-Fouling Systems, however, pose their own threats to marine environments. The Anti-Fouling Convention of 2001 banned the use of organotin compounds such as Tributyltin, and created a system for adoption of alternative anti-fouling biocides. In 2011, the Marine Environmental Protection Committee of the International Maritime Organization (IMO) released guidelines on bio-fouling management record keeping, installation, inspection, cleaning, maintenance, design and construction. Though these Guidelines provide a template for more effective and environmentally sound anti-fouling control and implementation, they are not mandatory. This article proposes that the member states of the IMO adopt the 2011 Guidelines as a mandatory instrument

Speciation without chromatography: Part 2. Determination of tributyltin by chloride generation flow injection atomic absorption spectrometry

A procedure is described for the quantitation of tributyltin in aqueous samples and extracts based on its relatively high volatility in halide media, permitting vapour phase sampling from the headspace above such samples.Tributyltin chloride (TBT-C1) was purged from various chloride containing aqueous matrices and collected on the surface of an iridium treated graphite tube for subsequent quantitation by graphite furnace atomic absorption. Iodide, bromide and chloride matrices were compared for their generation efficiency. The effect of acidity of the sample was also studied. An absolute detection limit of 1.3 ng TBT (as tin) was estimated, corresponding to a detection limit of 0.33 ng ml 1 for a 4 ml sub-sample. Method validation was achieved using NRCC PACS-2 (sediment) Certified Reference Material, for which reasonable agreement between certified and measured values of tributyltin content was obtained. A procedural concentration limit of detection of 66 ng g 1 TBT in the sediment could be achieved