Retrospective monitoring of organotin compounds in marine biota from 1985 to 1999: results from the German Environmental Specimen Bank

In archived samples from the German Environmental Specimen Bank, organotin compounds including tributyltin (TBT) and triphenyltin (TPT) as well as their degradation products were quantified. Biota samples from North Sea and Baltic Sea areas were analyzed by gas chromatography/atomic emission detection-coupling after extraction and Grignard or ethylborate derivatization. TBT and TPT were detected in nearly all samples. A decrease of TPT contamination was observed in bladder wrack, common mussels, and eelpout muscle tissues in the period 1985-1999. In this period, TPT concentrations in North Sea mussels decreased from 98 to 7 ng/g (as organotin cation concentration in wet tissue). Concentrations of TBT remained relatively constant with 17 +/- 3 ng/g for mussels from a site with nearby marine traffic and 8 +/- 2 ng/g for a more remote area. The results reflect that TBT is still used as a biocide in antifouling paints whereas the use of TPT as a co-toxicant in such preparations had been ceased in the 1980s. The fact that the use of TBT in antifouling paints was banned in 1991 for small boats within the European Community seems not to have resulted in a decrease of TBT levels in marine biota.