Horizontal distribution of butyltins in surface sediments from an enclosedbay system, Korea

Tributyltin (TBT), dibutyltin (DBT), and monobutyltin (MBT) compounds were quantitatively determined from surface sediment samples (total 59 stations) covering a whole basin where harbors, shipyards, and aquaculture farms wer e located. Butyltin compounds were detected from all the stations covering 640 km(2) of an enclosed bay system. TBT concentrations ranged from 4 to 38 2 ng/g as tin on a dry weight basis, and total butyltin concentrations, fro m 27 to 1763 ng/g. Horizontal distribution of TBT concentration showed appa rent negative gradients from harbors and shipyards, indicating that its con tamination was closely related to boating and dry-docking activities. Howev er, TBT concentrations were decreased steeply from source areas. Elevated D BT and MBT levels in creeks imply the possible input of DBT from industrial wastewater. Total butyltin concentrations in sediments are significantly c orrelated with particulate organic carbon concentration for the subset of s tations that are distant from source areas. (C) 1999 Published by Elsevier Science Ltd. All rights reserved.