• Organotin compounds;
  • Coastal waters;
  • Sediments;
  • Bivalves;
  • Partition coefficients


Tributyltin (TBT) and its degradation products, mono- (MBT) and dibutyltin (DBT) have been determined in the dissolved and particulate phases of seawater, sediments, and biota collected in some representative open and enclosed coastal areas of the western Mediterranean Sea. The highest levels were found in sediments and seawater of dry docks and marinas, closely related with boating activity and clearly decreasing according to the distance from the point sources. Triphenyl- (TPhT) and diphenyltin (DPhT) were also identified for the first time in seawater and sediments collected in marinas, exhibiting concentrations similar to TBT. Concentration ratios between TBT/DBT and TPhT/DPhT in each environmental compartment as well as the field partition coefficients (Kd, Kd, and Kb) of the different tin species point out the complexity of organotin speciation, because accumulation and degradation processes occur at different rates, depending on the environmental compartment.