The TBT ban: Out of the prying pan into the fire?

There is concern that organic booster biocides in the antifouling paints which will replace tributyltin (TBT)-based coatings could cause serious environmental damage. Domination of world markets by TBT-based paints inhibited research on alternative formulations, but the advent of the ban on TBT (probably from 2003) has kindled interest in them, Several recent publications stress our incomplete knowledge of the toxicity, sub-lethal impacts and persistence in the environment of these compounds. A particular concern is that synergistic interactions between biocides may enhance their toxic effects. It has been reported that the use of the triazine compound Irgarol as an antifoulant is responsible for environmental levels of this biocide which could affect primary production. It is argued that the ban on TBT-based antifoulants is desirable but, in view of these uncertainties, it should be delayed until alternatives, which have been proved to be less harmful to the environment than TBT, are available. As a result of regulations and developments in paint technology, inputs of TBT into the marine environment are nos low, and can be decreased further. (C) 2000 Elsevier Science Ltd., All rights reserved.