According to Marine Paint research, is defined as: A particular species adhering to and growing on a hull depends on the waters through which the vessel moves, the season, and how much time the vessel spends in port.
Bacteria, cyanobacteria, diatoms (unicellular algae), and protozoans (unicellular animals) are common species in the initial microfouling. Diatoms excrete large quantities of extracellular polymeric substances (EPS), which contribute to the sliminess of the surface.
Following the microfouling, a macrofouling community establishes itself, consisting of soft or hard foulers. Soft foulers include higher algae, such as the green algae Ulva intestinalis. Ulva releases spores which, on touching a surface, secrete an adhesive consisting of glycoproteins to ensure that the algae adhere to and grow on the surface. Other types of soft foulers are sea squirts, sea anemones or soft corals. Hard foulers include mussels, tubeworms and barnacles, all of which have highly developed abilities to adhere strongly to the surface.
Different types of chemical adhesives, all have the same function; to allow the species to attach itself strongly to the surface.
Consequently, the fouling on a ship’s hull becomes a unique ecosystem in itself, but one that creates major problems for both commercial shipping and leisure boating.
The legislative pressure to develop antifouling strategies with low environmental impact, has led to a substantial commitment from national and international authorities.
The International Maritime Organisation (IMO), agreed in 2001 on a convention to ban of tributyltin (TBT)-based paints, as it has been shown to have severe ecotoxicological effects.
As of 2003, it is forbidden to apply new TBT-containing coatings, and from 2008 there is a ban on the presence of such paints on ship hulls for those states that adhere to the convention.
55 states representing 78% of the world tonnage
When developing new antifouling agents it is of the utmost importance to rigorously anticipate and assess the risk of long-term effects on the environment.