Environmental Impact of Tributyltinbiocideson Coastal Marine Systems in the NE Adriatic Sea

Antifouling biocides, as tributyltin (TBT), have been developed to prevent settlement of organisms on vessels and therefore were directly introduced into the marine environment. Their widespread use caused high levels of contamination and raised concerns about their toxic effects on marine communities. Nowadays, the usage of TBT-based antifouling paints has been banned in many countries worldwide. However, overview of the recently published data demonstrates that marine environment is still polluted with TBT. Obviously, the ban cannot solve the problem of contamination immediately since TBT is highly persistent in sediments, which therefore represent a long term source of TBT in the marine environment. Since TBT degradation in sediments occurs very slowly, with half-lives from several years to decades, it controls the overall persistence of TBT in the entire environment. Consequently, the complete knowledge on degradation process is of crucial importance for the assessment of the time period in which TBT pollution will be present. Here we shown that organic matter, by controlling TBT adsorption/desorption processes, influences the TBT degradation efficiency and consequently defines its persistence in contaminated sediments, which thus increases in sediments rich in organic matter.