Concentrations of the antifouling compound Irgarol 1051 and of organotins in water and sediments of German North and Baltic Sea marinas

A survey of 2-methylthio-4-tert-butylamino-6-cyclopropylamino-s-triazine (I rgarol 1051) and organotins, used as biocides in antifouling paints, was ca rried out in German marinas of the North and Baltic Sea. Highest levels of the s-triazine herbicide mere found in Baltic Sea marinas where water excha nge was restricted (mater up to 440 ng/l; sediment about 220 ng/g dry weigh t), while in the North Sea marinas with higher water exchange rates Lower c oncentrations were encountered (water 11-170 ng/l; sediment 3-25 ng/g dry w eight). Although the application of the antifouling agent tributyltin (TBT) was banned for small vessels (< 25 m) in Germany and other countries in 19 89, significant levels of TBT between 570 to 17 000 ng/g dry weight, lower concentrations of triphenyltin (TPT) of up to 3800 ng/g as well as the TBT degradation products dibutyltin and monobutyltin occurred in sediment sampl es of the Baltic Sea marinas. In the North Sea marinas with stronger mater exchange the TBT sediment levels ranged from about 80 to 720 ng/g dry weigh t. This study shows parallel contamination patterns of Irgarol and organoti ns in North and Baltic Sea marinas and the persistence of several organotin s in these sediments about eight years after the ban. A seasonal dependence of Irgarol 1051 concentrations was found both in the water and sediment sa mples, with maxima during the periods March-May/JulySeptember, while during the winter period December-January low values mere encountered though meas urable amounts remained in the sediment. A mean value of the partitioning c oefficient log K-OC=3.3+/-0.72 was inferred from the water and sediment con centrations determined in seven Baltic Sea marinas. (C) 2000 Elsevier Scien ce Ltd. All rights reserved.