Supplementary information

As a hydrolyzable self-polishing type polymer contained in ship bottom paints, a copolymer of tributyl tin methacrylate (tributyl[(2-methyl-1-oxo-2-propenyl)oxy]stannane) and methylmethacrylate, etc. has been used. This copolymer is hydrolyzed in water and releases bistributyl tin oxide. Because the hydrolyzed polymer part is transformed into carboxylic acid which is water-soluble, the polymer can maintains water-solubility and constantly keep the active surface.
However, bistributyl tin oxide released at the time of hydrolysis is highly toxic, works as Endocrine Disruptor, and raises concerns about detrimental effects on the ecological system.