Biofouling growth in cold estuarine waters and evaluation of some chitosan and copper anti-fouling paints.
Ecological concerns about antifouling paints containing non-green tin and copper compounds have highlighted the need for environmentally friendly alternatives. We report here a field test conducted in estuarine waters over two months designed to evaluate the efficiency of a number of active natural and man-made chemical ingredients added into a silicon-polyurethane marine paint. Early steps of biofouling in cold seawater of the St. Lawrence Estuary (Canada) were observed. Analyses, including dry biomass, flow cytometry and spectrofluorimetry, demonstrated a short-term antibacterial action of chitosan-based paints although no significant anti-algal action was observed. Cuprous oxide paints were efficient against bacteria and algae invasion in the first two weeks, especially those with added organic biocides such as isothiazolone and copper pyrithione. However, the overall dry biomass and chlorophyll a content were similar for all chitosan-and copper-based paints after 63 days. Microscopic observations revealed variation in the highly diverse benthic diatom population including species Navicula, Melosira, Cocconeis, Nitshzcia, Fragilaria and Amphora. Results suggest no real long-term efficiency for tested antifouling paints and highlight a particular need for green antifouling ingredients that are active under northern estuarine conditions.
Pelletier
Émilien
É
Institut des Sciences de la Mer de Rimouski, Université du Québec à Rimouski, 310 Allée des Ursulines, C.P.3300. Rimouski, QC, G5L 3A1, Canada.
Bonnet
Claudie
C
Institut des Sciences de la Mer de Rimouski, Université du Québec à Rimouski, 310 Allée des Ursulines, C.P.3300. Rimouski, QC, G5L 3A1, Canada.
Lemarchand
Karine
K
Institut des Sciences de la Mer de Rimouski, Université du Québec à Rimouski, 310 Allée des Ursulines, C.P.3300. Rimouski, QC, G5L 3A1, Canada.
D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects; D057219:Biofouling / Q000517:prevention & control*; D018533:Biomass; D002170:Canada; D048271:Chitosan / Q000032:analysis / Q000494:pharmacology*; D003080:Cold Temperature; D003300:Copper / Q000032:analysis / Q000494:pharmacology*; D017377:Diatoms / Q000187:drug effects; D063366:Estuaries; D010150:Paint; D010839:Phytoplankton / Q000187:drug effects; D012623:Seawater / Q000382:microbiology*
D000900:Anti-Bacterial Agents; D003300:Copper; D048271:Chitosan; C030973:cupric oxide