Tributyltin determination

Quevauviller, Ph., Astruc, M., Ebdon, L., Kramer, G.N. and Griepink, B. (1994c) Interlaboratory study for the improvement of tributyltin determination in harbour sediment (RM 424). Appl. Organometal. Chem., 8(5), 639. 

P. Quevauviller, M. Astruc, R. Morabito, F. Ariese, L. Ebdon, Collaborative evaluation of methods for tributyltin determinations in sediments and mussel tissue, Trends Anal. Chem., 19 (2000), 180D188. 

Single blind protocol was followed levels spiked were unknown to the analyst doing the tributyltin determinations. Values were compared through a third party. 

Dibutyltin No significant neurotoxicity reported Yes. NOAEL = 2.5 (teratogenicity) and 1.0/5.0 (maternal toxicity) mg/kg body weight per day (as DBTC) Aromatase inhibition present (at least 10 times less potent than tributyltin) no imposex in vivo in invertebrates Yes. NOAEL could not be determined lowest dose reported to cause immunological effects = 2.5 mg/kg body weight per day (as DBTC)... 

TBTO is a colorless liquid of low water solubility and low polarity. Its water solubility varies between <1.0 and >100 mg/L, depending on the pH, temperature, and presence of other anions. These other anions determine the speciation of tributyltin in natural waters. Thus, in sea water, TBT exists largely as hydroxide, chloride, and carbonate, the structures of which are given in Figure 8.5. At pH values below 7.0, the predominant forms are the chloride and the protonated hydroxide at pH8 they are the chloride, hydroxide, and carbonate and at pH values above 10 they are the hydroxide and the carbonate (EHC 116). 

Temperature programming packed-capillary and open capillary HTLC-ICP-MS (up to 200 °C) has been reported [738]. //.HTLC-ICP-MS instrumental coupling has been applied to organotin (tetraethyltin, tributyltin chloride and triphenyltin chloride) and organolead (tetramethyllead and tetraethyllead) compounds [756]. HTLC-ICP-MS can be used for the determination of organometallic compounds at low concentrations. The observed limit of detection (LOD) was 5pg for Pb in... 

Mono-, di- and tributyltin ion species (in water) have been determined by cation exchange IC-ICP-MS at 0.2 ng detection limits [856]. IC is also particularly useful for HSE purposes, such as the determination of acid gases in the workplace. Applications of IC have been reviewed [857]. 

Tributyltin has been determined in estuarine waters by high-performance liquid chromatography with fluorometric detection in a method described... 

An estimate of the accuracy of both analytical methods was performed on bis(tri-n-butyltin) oxide and tri-n-butyltin chloride solutions (8.9-35.6 ig/l) prepared in filtered (0.45 im) near-shore seawater free of detectable organ-otins. Average mean recoveries of 92.8% by both methods were determined for tributyltin standard solutions. Low ng/1 levels of mono-, di-, and tributyltin were found in samples taken from San Diego Bay. 

Valkirs et al. [105] have conducted an interlaboratory comparison or determinations of di- and tributyltin species in marine and estuarine waters using two methods, namely hydride generation with atomic absorption detection and gas chromatography with flame photometric detection. Good agreement was obtained between the results of the two methods. Studies on the effect of storing frozen samples prior to analysis showed that samples could be stored in polycarbonate containers at - 20 °C for 2 - 3 months without significant loss of tributyltin. 

Encinar et al. [128] used a spike containing 119Sn enriched mono-, di-, and tributyltin to determine butyltin compounds in seawater GC-ICPMS. Reverse spiking was used to assess species transformation during derivativisation. 

Laughlin et al. [122] analysed chloroform extracts of tributyltin dissolved in seawater using nuclear magnetic resonance spectroscopy. It was shown that an equilibrium mixture occurs which contains tributyltin chloride, tributyl tin hydroxide, the aquo complex, and a tributyltin carbonate species. Fluorometry has been used to determine triphenyltin compounds in seawater [123]. Triph-enyltin compounds in water at concentrations of 0.004-2 pmg/1 are readily extracted into toluene and can be determined by spectrofluorometric measurements of the triphenyltin-3-hydroxyflavone complex. 

A method for tributyltin in sediments consists of extraction with anhydrous acetic acid, hydride generation, cold trapping and end analysis by GC-AAS using a quartz furnace75. Reduction with NaBFLi followed by solvent extraction, concentration and GC-FPD was proposed for simulaneous determination of di- and tributyltin residues in sea water LOD 10 ng/L for 1 L sample, with 87.1-98.4% of Sn recovery76. 

A method for sample preparation allows determination of total tin and tributyltin ions in biological materials. End analysis by ETAAS, using a tungstate-treated graphite tube, allows LOD for tributyltin Sn of 0.4 ng/g79. An alternative method for sea water uses in situ concentration of Sn hydrides on a zirconium-coated graphite tube, followed by ETAAS absolute LOD 20 and 14 pg for tributyltin ion and total Sn, respectively, with corresponding RSD of 5.6 and 3.4%80. 

Tributyltin oxide and its metabolites were determined in urine after conversion to chlorides with HC1, extraction with ether containing tropolone (1), conversion to hydrides with NaBFLt, extraction with hexane and GC-AAS end-analysis LOD 1 pg/L for BuSnFL and Bu2SnH2, and 2 pg/L for Bu3SnH87b. 

Ion chromatography using a weak cation-exchange column with direct conductivity detection was applied in the determination of aqueous tributyltin ions, with short elution times LOD 0.01 ppm, without preconcentration or derivatization. No organotin remains adsorbed on the column94. 

Determination of trace levels of tributyltin residues in sediments can be accomplished by solvent extraction, dilution and FIA (flow injection analysis) into the ionspray of a tandem mass spectrometer, using the 179/291 m/z pair LOD 0.2 p-g Sn/g103. 

A method for determination of volatile thiols consists of preparing the corresponding tributyltin mercaptides according to reaction 31. After concentrating the mercaptides they are hydrolysed with aqueous hydrochloric acid, and the salted-out thiols are determined by GC-FTD. This was applied to analysis of thiols in cigarette smoke284. 

Scheme 9). This labelled tin oxide was used to determine the clearance of bis(tributyltin) oxide from mice. The study was undertaken because bis(tributyltin) oxide is used to control schistomiasis. Many other labelled tin compounds have been used as tracers for tin compounds in fish, in animals and in the environment34. 

The radioactive tin-125 isotope in the bis(tributyltin-125) oxide enabled Klotzer and Gomer40 to use a neutron activation analysis to determine the percent tin in the organotin compounds formed in the photochemical reaction between bis(tributyltin-125) oxide and glucose (equation 39). 

Abeywickrema and Beckwith162 have measured the primary hydrogen-deuterium kinetic isotope effect for the reaction between an aryl radical and tributyltin hydride. The actual isotope effect was determined by reacting tributyltin hydride and deuteride with the ort/ro-alkcnylphcnyl radical generated from 2-(3-butenyl)bromobenzene (equation 111). 

The exo and the endo ring closures (the kc reactions) are in competition with the aryl radical-tributyltin hydride transfer (the ks or ku reaction). These workers162 used this competition to determine the primary hydrogen-deuterium kinetic isotope effect in the hydride transfer reaction between the aryl radical and tributyltin hydride and deuteride. 

Tributyltin deuteride has also been used to help determine the mechanism of the electrochemical oxidation of carbonylmanganese phosphites and carbonylmanganese phosphines (equation 113). 

In one study, Ingold and coworkers166 measured the rate constants for the reactions of several alkyl radicals with tributyltin hydride using a laser flash photolytic technique and direct observation of the tributyltin radical. They also used this technique with tributyltin deuteride to determine the primary hydrogen-deuterium kinetic isotope effects for three of these reactions. The isotope effects were 1.9 for reaction of the ethyl radical, and 2.3 for reaction of the methyl and n -butyl radicals with tributyltin hydride at 300 K. 

San Filippo and coworkers163 have determined the temperature dependence of the primary hydrogen-deuterium kinetic isotope effects for the hydrogen transfer reactions between several organic radicals and tributyltin hydride (deuteride) see equation 116. 

Dowson and coworkers studied partitioning and sorptive behavior of tributyltin (TBT) and its degradation products, dibutyltin (DBT) and monobutyltin (MBT) in the aquatic environment107. The determination of the sorptive behavior of TBT is necessary in order to understand its fate in freshwater and estuary environments. The results indicate that MBT and TBT in freshwater will be partitioned to a lesser extent towards the particulate phase, whereas DBT exhibits a 50 50 partitioning between the particulate and solution phases. In estuary waters, MBT will almost exclusively be adsorbed on the particulates, while TBT will be predominantly in the solid-phase fractions but 10-30% may remain in solution. DBT, in contrast, is solubilized in estuary waters. The order of adsorption to particulate matter for butyltins is MBT > TBT > DBT107. 

Penninks108 assessed the evaluation of a safety factor to determine a Tolerable Daily Intake (TDI) value for the environmental contaminant bis(tributyltin)oxide (TBTO). The... 

Muller [76] has described a gas chromatographic method for the determination of tributyltin compounds in sediments. The tributyltin compounds are first converted to tributylmethyltin by reaction with ethyl magnesium bromide, and then analysed using capillary gas chromatography with flame photometric detection and gas chromatography-mass spectrometry. Tributyltin was found in samples of sediment and these results demonstrated that the technique has detection limits of less than 0.5pg L 1. 

Stephenson and Smith [84] used graphite furnace atomic absorption spectrometry to determine tributyltin in sediments. Recoveries from spiked samples ranged to from 72-111%. The detection limit was 2.5mg kgp1 of sample. 

Ebdon et al. [88] have discussed a programme to improve the quality of analytical results in the environmental monitoring of organotin compounds. They discuss the evolution of a sensitive, reliable and robust analytical method for the determination of tributyltin, with emphasis on the difficulties of determining it at the ng per litre levels at which it was usually encountered, more especially as other forms of tin frequently occurred together at similar levels. The preparation of a standard reference sample, for use in interlaboratory comparative determinations, under the aegis of the Bureau of Community Reference of the EU is described, and plans for subsequent distributions of blank, artificially spiked, and genuinely affected sediments are sketched. 

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