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The presence of the highly toxic antifouling agent tributyltin (TBT) and its degradation products was determined in four species of mussels collected from 34 locations in fresh water in Ontario and in sea water on Canada's west and east coasts. The purpose of the study was to establish baseline information in order to assess TBT trends in mussels after the 1989 Canadian regulation of antifouling uses of TBT. In fresh water, concentrations of TBT were much higher in zebra mussels (Dreissena polymorpha) than in Elliptio complanata or Lampsilis radiata radiata. High concentrations of TBT were also found in Mytilus edulus in sea water. Residues of TBT in all species were similar to those that have been determined in other parts of the world before and after the regulation of antifouling uses of TBT in various countries. Analyses for degradation products indicated that zebra mussels metabolize TBT at about the same rate as L. radiata radiata and M. edulis, but more slowly than E. complanata. © 1997 John Wiley & Sons, Ltd.

A survey was conducted of water and sediment from across Canada in 1993-94 to assess the effectiveness of the 1989 regulation of antifouling uses of tributyltin (TBT) under the Canadian Pest Control Products Act. The survey was also designed to assess concentrations of 13 other organotin species in water and sediment, and in sewage treatment plant influents, effluents and sludges. The main conclusion is that the 1989 regulation has only been partially effective. It has had some effect in the reduction of TBT concentrations in fresh water, but not in sea water. It has had less effect in the reduction of TBT concentrations in sediment, probably because of the longer persistence of TBT in sediment than in water. In many locations the TBT concentration was high enough to cause acute and chronic toxicity to aquatic and benthic organisms. In some areas there may be potential for recycling TBT from contaminated sediments back into the water column. In addition, it appears that large harbours that handle ships legally painted with TBT-containing antifouling paints continued to experience ecotoxicologically significant TBT contamination. Other organotin species found appear to pose no acute or chronic hazards to fresh water or marine organisms, but nothing is known of their hazards to benthic organisms. The presence of monooctyltin and dioctyltin in sediments and sewage treatment plant influents, effluents and sludges is reported for the first time, and tripropyltin is quantified in sediments for the first time.

The two commonly used derivatization techniques for the speciation of organotin compounds in biological tissue, namely, (1) direct in situ derivatization with sodium tetraethylborate, and (2) tropolone extraction followed by derivatization with ethyl Grignard reagent, were evaluated and validated using a spiked tissue and reference fish tissue (NIES No. 11). Their applications in the analysis of real mussels are given.

A highly sensitive and specific method is described for the determination of methyl-cyclopentadienylmanganese tricarbonyl (MMT) in gasoline and environmental samples by gas chromatography-plasma atomic emission detection (GC-AED). The procedure is simple, rapid and free from interferences. The absolute limit of detection is 0.5 fg of MMT (0.5 x 10 -15 g) expressed as Mn. The precision for replicate injections (n=5) of an MMT solution (10 pg Mn) was 2.8% relative standard deviation (RSD). Applications of the method to analysis of gasoline (petrol), and preliminary results of the analyses of environmental samples such as air and roadside dirt, are given.

An investigation of the extraction recovery of butyltin species in sediment by supercritical fluid extraction (SFE) is presented. Satisfactory recoveries for TBT (93.5 ± 3.7%) and DBT (91.5 ± 3%) are achieved. The recovery for MBT from spiked sediment (62 ± 5.1%) is the highest value so far achieved by the SFE technique. A comparison of the supercritical fluid extraction with the improved tropolone solvent extraction technique for the butyltin species is presented. The results of the analysis of a reference sediment (PACS-1) are also given.

The relationship between bioaccumulation and toxicity of tributyltin in Hyalella azteca was determined for future use in identifying freshwater sites of TBT induced toxicity in the field. Hyalella accumulated waterborne TBT rapidly, reaching equilibrium within 1 week. Short exposure times are, therefore, sufficient to measure TBT availability in laboratory or field exposures. Accumulation was not affected significantly by body size for animals between 0.1 and 0.6 mg dry weight, eliminating the need for a body size correction factor. Young amphipods were more sensitive to TBT than adults when both were exposed for 1 week. The 4-wk LC50 initiated with 0–1-week-old young was 4.8 nM. TBT accumulation was approximately proportional to TBT in water, and the 4-week LC50 expressed on a body concentration basis was 110 nmole/g dry weight. Accumulation of TBT by adult Hyalella to concentrations of about 100 nmole/g or more during short term (1-wk) exposures to environmental samples would suggest chronic TBT-induced toxicity is present at those sites.