Sorption of tributyltin in seawater by municipal solid waste compost

The use of municipal solid waste (MSW) compost as a sorbent for tributyltin (TBT) in seawater was investigated. TBT-contaminated seawater, both artificially prepared and that collected from Msida Creek yacht marina (Malta), was allowed to percolate through untreated and water-washed columns of compost and then analysed for organotins; using gas chromatography-flame photometric detection. About 90% of dissolved TBT ranging in concentration from about 800 to 8000 ng(Sn)l(-1) was sorbed by treating 500 ml solutions with 100 g untreated compost. On the other hand, no detectable breakthrough of TBT was observed from compost that had previously been washed by water to remove soluble organic matter. Breakthrough of TBT from unwashed compost is thought to be due to formation of complexes between the soluble organic matter in compost and aquated TBT, which renders the organotin more hydrophilic. The use of washed MSW compost as sorbent for the purification of TBT-contaminated waters generated in large quantity during hull-cleaning activities in drydocks is suggested as a mitigatory measure against the impact of TBT on the coastal marine environment. Copyright (C) 2001 John Wiley Sons, Ltd.