Non-toxic alternative compounds for marine antifouling paints

In order to search for alternative non-pollutant substances as antifouling compounds, the effects of sodium benzoate and different tannins (from chestnut, mimosa and quebracho) were studied. Balanus amphitrite (Cirripedia, Balanidae) nauplii were used in the laboratory for the bioassays. The results showed that both benzoates and tannins have a narcotic effect on these larvae, this effect was faster as the concentration of these compounds was increased. Larvae rapidly recovered when they were transferred to fresh, non-toxic, artificial sea water. Field trials in Mar del Plata harbor confirmed that soluble matrix paints, formulated with sodium benzoate or tannins as antifouling agents, were successful in preventing barnacle attachment. These results indicate the potential bioactivity of these compounds on fouling organisms.