Evaluation of low copper content antifouling paints containing natural phenolic compounds as bioactive additives

M. PÉREZ; M. GARCÍA; G. BLUSTEIN

MARINE ENVIRONMENTAL RESEARCH

ELSEVIER SCI LTD

Lugar: Amsterdam; Año: 2015 vol. 109 p. 177 - 184

0141-1136

Cuprous oxide is the most commonly used biocide in antifouling paints. However, copper has harmfuleffects not only on the fouling community but also on non-target species. In the current study, weinvestigated the use of thymol, eugenol and guaiacol in this role combined with small quantities ofcopper. Phenolic compounds were tested for anti-settlement activity against cyprid larvae of the barnacleBalanus amphitrite and for their toxicity to nauplius larvae.Thymol, eugenol and guaiacol were active for anti-settlement but guaiacol had the disadvantage ofbeing toxic to nauplius larvae. However, all of them showed therapeutic ratio>1.Antifouling paints with thymol (low copper content/thymol, LCP/T), eugenol (low copper content/eugenol, LCP/E) and guaiacol (low copper content/guaiacol, LCP/G) combined with small copper contentwere formulated for field trials. After 12 months exposure in the sea, statistical analysis revealed thatLCP/T and LCP/E paints were the most effective combinations and had similar performances to controlpaints with high copper content (traditional cuprous oxide based paints). In contrast, LCP/G paint wasonly partially effective in preventing and inhibiting biofouling and was colonized by some hard and softfoulers. However, this antifouling paint was effective against calcareous tubeworm Hydroides elegans.In the light of various potential applications, thymol, eugenol and guaiacol have thus to be consideredin future antifouling formulations.