Determination of tributyltin in marine sediment and waters by pressurised solvent extraction and liquid chromatography-tandem mass spectrometry

[Determination of Tributyltin and Triphenyltin in Fish and Shellfish Using Accelerated Solvent Extraction and Liquid Chromatography with Tandem Mass Spectrometry]

A determination method for tributyltin (TBT) and triphenyltin (TPT) in fish and shellfish using an accelerated solvent extractor (ASE) and LC-MS/MS was developed. The chromatographic separation was conducted on a Poroshell 120 EC-C18 column using an isocratic mobile phase of 0.1% formic acid in 70% methanol. Sample preparation was performed using ASE at 125℃ with n-hexane and a cleanup using a Florisil cartridge. Internal calibration curves using deuterium-labeled TBT and TPT were employed for quantification. For both TBT and TPT, the calibration curves were linear in the range of 0.2-250 ng/mL, and the method quantification limits were 0.8 ng/g for both TBT and TPT. A National Institute for Environmental Studies certified reference material, No. 15 (adductor muscle of scallop), was analyzed to assess the performance of the developed method. The trueness, relative standard deviations of repeatability, and within laboratory reproducibility of this method, evaluated using a recovery test with four spiked fish species and one shellfish, ranged from 89.3 to 105.3%, 1.0 to 4.5%, and 1.3 to 7.6%, respectively.

Fast and Feasible Ultrasound-Assisted Pretreatment for the Determination of Organotin Compounds in Environmental Samples

The goal of this study was to improve an already established reference method, such as the one devoted to organotin compounds determination (Reference Method for Marine Pollution Studies, No. 59, UNEP). The proposed upgrade consists of replacing the mechanical shaking by ultrasound energy and applying low temperature throughout the whole procedure. The optimization of the new operational conditions was performed by using a factorial design. Quality control was performed using a certified sediment reference material (PACS-2) for sediments (82.5-97% of recovery) and recoveries on spiked samples for suspended particulate matter (SPM) and mussels (94-100%). The proposed procedure was applied to surface sediment samples, SPM, and native bivalve mollusks (Brachidontes rodriguezii) collected in Bahia Blanca estuary, a very industrialized zone. The relative standard deviation (RSD %) of the environmental samples were less than 7.9%. It is important to note that the proposed procedure reduced the sample pretreatment time about seven times.

Physiological Responses in Chinese Rare Minnow Larvae Following Exposure to Low-Dose Tributyltin

In the present study, the antioxidant response and acetylcholinesterase (AChE) activity were measured in Chinese rare minnow larvae (Gobiocypris rarus) after exposure to tributyltin (TBT) (0, 100, 400 and 800 ngL(-1)) for 7 days, as well as the expression of a series of genes, including cr, aptase and prl genes involved in the ion-regulatory process and igfbp3 and gh related to growth rate. Results shows that oxidative stress was generated in fish exposed to TBT, as evidenced by elevated malondialdehyde levels and the inhibition of antioxidant parameters. The activity of acetylcholinesterase (AChE) was also inhibited in fish under higher TBT stress. Moreover, genes involved in ion regulation and growth were affected, based on the regulated transcription of the cr, atpase, gh, prl and igfbp3 genes in the treated groups. The observed effects of TBT upon antioxidant responses and altered expression of genes provides insight into the use of these molecular biomarkers in evaluating mechanisms of TBT toxicity in fish.