Chambers, Stokes, Walsh, and Wood surveyed the landscape of non-toxic anti-fouling technologies under development, evaluating each for technical readiness, projected efficacy, durability, and scalability to commercial application. The review covered silicone-based foul-release coatings, enzyme-active surfaces that degrade biological adhesives, micro- and nano-textured surfaces inspired by naturally antifouling organisms such as shark skin and pilot whale epidermis, and electrochemical systems that generate localised biocidal conditions at the surface.
Among the technologies assessed, silicone foul-release coatings were identified as the most commercially mature, already deployed on ship hulls and beginning to appear in aquaculture trials. Enzyme-based coatings showed strong laboratory results but faced stability and cost challenges at scale. Biomimetic surface textures demonstrated proof-of-concept effectiveness against specific foulers but lacked the broad-spectrum activity needed for open-water deployment. The authors concluded that hybrid approaches combining two or more non-toxic mechanisms held the greatest promise for matching the performance of copper-based systems.
For a current overview of which non-toxic methods have reached farm-level application, see copper-free anti-fouling. The solutions comparison tool evaluates commercially available options, and the article on EU regulatory trends explains the policy drivers accelerating the shift away from biocidal coatings.