INHIBITION OF MARINE BIOFOULING BY POTASSIUM SORBATE

GUILLERMO BLUSTEIN; MÓNICA T. GARCÍA; MIRIAM C. PÉREZ; BEATRIZ DEL AMO; MIRTA STUPAK

Kobe, Japón

Congreso; 14th INTERNATIONAL CONGRESS ON MARINE CORROSION AND FOULING; 2008

Japan Institute of Marine Engineering

Traditionally, copper or organotin based coatings were commonly used to inhibit biofouling on underwater structures. Although these paints are highly effective, they are dangerous to the marine environment due to they affect a wide spectrum of non-target organisms. New trends in antifouling technology are focused to the use of environmental friendly-compounds. As yet, the development of antifouling coatings based on natural products has not been obtained at a commercial scale. In addition to its antifouling characteristics, products must have properties that make them suitable, i.e. low toxicity, a broad spectrum of activity against algae and invertebrates, low cost, etc. For this reason, we search for another possibility for biofouling control. The aim of this study is to evaluate the activity of potassium sorbate, a synthetic compound widely used as food preservative, on larval survival of Balanus amphitrite through laboratory antifouling bioassays and field trials. In the lab potassium sorbate solutions ranged between 0.1 and 0.001M were prepared. Toxicity and settlement tests were conducted using nauplii II and cyprids respectively, and results were recorded after 24 h incubation. Significant differences between treatment and controls were observed in solutions higher than 0.0125M, above this concentration, solutions were effective in inhibiting both nauplii swimming movements and cyprids attachment. When larvae were transferred to fresh artificial seawater they could recover and follow their development, this observation confirms that the effect of potassium sorbate is not permanent. For field trials, potassium sorbate was entrapped into a non-toxic varnish. Acrylic panels coated with the varnish were exposed in Mar del Plata harbour, Argentina. Biofouling percentage cover was estimated after 15 days. A great decrease in micro and macrofouling density and diversity in relation to controls was detected (p<0.05).. Although these paints are highly effective, they are dangerous to the marine environment due to they affect a wide spectrum of non-target organisms. New trends in antifouling technology are focused to the use of environmental friendly-compounds. As yet, the development of antifouling coatings based on natural products has not been obtained at a commercial scale. In addition to its antifouling characteristics, products must have properties that make them suitable, i.e. low toxicity, a broad spectrum of activity against algae and invertebrates, low cost, etc. For this reason, we search for another possibility for biofouling control. The aim of this study is to evaluate the activity of potassium sorbate, a synthetic compound widely used as food preservative, on larval survival of Balanus amphitrite through laboratory antifouling bioassays and field trials. In the lab potassium sorbate solutions ranged between 0.1 and 0.001M were prepared. Toxicity and settlement tests were conducted using nauplii II and cyprids respectively, and results were recorded after 24 h incubation. Significant differences between treatment and controls were observed in solutions higher than 0.0125M, above this concentration, solutions were effective in inhibiting both nauplii swimming movements and cyprids attachment. When larvae were transferred to fresh artificial seawater they could recover and follow their development, this observation confirms that the effect of potassium sorbate is not permanent. For field trials, potassium sorbate was entrapped into a non-toxic varnish. Acrylic panels coated with the varnish were exposed in Mar del Plata harbour, Argentina. Biofouling percentage cover was estimated after 15 days. A great decrease in micro and macrofouling density and diversity in relation to controls was detected (p<0.05).Balanus amphitrite through laboratory antifouling bioassays and field trials. In the lab potassium sorbate solutions ranged between 0.1 and 0.001M were prepared. Toxicity and settlement tests were conducted using nauplii II and cyprids respectively, and results were recorded after 24 h incubation. Significant differences between treatment and controls were observed in solutions higher than 0.0125M, above this concentration, solutions were effective in inhibiting both nauplii swimming movements and cyprids attachment. When larvae were transferred to fresh artificial seawater they could recover and follow their development, this observation confirms that the effect of potassium sorbate is not permanent. For field trials, potassium sorbate was entrapped into a non-toxic varnish. Acrylic panels coated with the varnish were exposed in Mar del Plata harbour, Argentina. Biofouling percentage cover was estimated after 15 days. A great decrease in micro and macrofouling density and diversity in relation to controls was detected (p<0.05).hen larvae were transferred to fresh artificial seawater they could recover and follow their development, this observation confirms that the effect of potassium sorbate is not permanent. For field trials, potassium sorbate was entrapped into a non-toxic varnish. Acrylic panels coated with the varnish were exposed in Mar del Plata harbour, Argentina. Biofouling percentage cover was estimated after 15 days. A great decrease in micro and macrofouling density and diversity in relation to controls was detected (p<0.05).entrapped into a non-toxic varnish. Acrylic panels coated with the varnish were exposed in Mar del Plata harbour, Argentina. Biofouling percentage cover was estimated after 15 days. A great decrease in micro and macrofouling density and diversity in relation to controls was detected (p<0.05). Because potassium sorbate is not lethal, it has an excellent potential as an antifouling agent.