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.

The extent of pollution with organotin compounds was investigated in water, sediment and bivalve mussels (Mytilus galloprovincialis) from the Northern Adriatic Sea. Butyl-, phenyl-and octyltin species were quantified after extraction and derivatisation by gas chromatography-mass spectrometry in a total of 99 samples from the period from 2000 to 2006. The accuracies of the analytical procedures were checked by spiking of unpolluted water samples and by the analysis of standard reference materials (harbour sediment PACS-2 and mussel tissue ERM-CE 477). Among organotin species analysed in samples butyltins were the predominant. Tributyltin was found to be present in the highest concentrations, suggesting its recent input into the marine environment. Butyltins were detected at all sites surveyed (sum of butyltins was up to 718 ng Sn L −1 , 3,552 ng Sn g −1 d.w. and 9,991 ng Sn g −1 d.w. in water, sediment and mussel samples, respectively), phenytins in much lower concentrations (up to 31 ng Sn L −1 , 326 ng Sn g −1 d.w. and 442 ng Sn g −1 d.w. in water, sediment and mussel samples) and to a much smaller extent, while octyltins were not detected at any location. The spatial distribution of tributyltin was closely related to boating, with the highest concentrations found in marinas (up to 586 ng Sn L −1 for water samples, 1,995 ng Sn g −1 d.w. for sediment and 6,434 ng Sn g −1 d.w. for mussel samples). The temporal distribution clearly indicates a decrease of organotin pollution at all sites.

The efficiency of different extraction procedures for the simultaneous determination of butyltin compounds in marine sediments by gas chromatography-mass spectrometry (GC-MS) was critically evaluated in the present work. Three different polar solvents (acetic acid, a mixture of acetic acid with methanol, and a mixture of acetic acid, methanol, and water) and three different extraction approaches (mechanical shaking, ultrasonic, and microwave-assisted extraction) were used for the extraction of butyltin compounds from PACS-2 certified marine sediment reference material. Before determination by GC-MS, extracted butyltin species were derivatized with sodium tetraethyl borate and extracted into iso-octane. The results indicated that 30-min ultrasonic extraction with 100% acetic acid provided satisfactory recoveries for all certified butyltins. The developed analytical method was successfully applied for determination of butyltin compounds in coastal sediments of the Northern Adriatic Sea. The results demonstrated that butyltins were present in all sediments analysed.