Can the input of biocides and polymeric substances from antifouling paints into the sea be reduced by the use of non-toxic hard coatings?

Antifouling coatings are used to protect boat hulls from fouling organisms. The paints are designed to release biocides and by this prevent fouling organisms to attach. Until now the simultaneous release of the bulk plastic material has been over-looked. In this study the amount of antifouling paints on ships and leisure boats in Scandinavian countries and Germany has been compared and a calculation of the release of micro plastics has been performed. The result shows that use of a biocide-free hard coating will completely reduce outlet of biocides and the input of polymers will dramatically be reduced from at the most 5% in comparison to traditional paints where the release rate of plastics is estimated to be 70–85%. The advantage for the boat owners will be large since the hard maintenance work will be reduced, release of micro plastics will be low and thus lead to an improved environment. •Traditional antifouling paints release both biocides and microplastics.•A change of behaviour to hard cleanable biocide-free methods is beneficial to the environment.•Biocide-free hard cleanable coating can be used on both ships and leisure boats.•Hard cleanable biocide-free paint is preferred over traditional paints.