Release and Detection of Nanosized Copper from a Commercial Antifouling Paint

Oral Presentation

Prepared by A. Adeleye, A. Keller
University of California, Santa Barbara, 2045 Bren Hall, University of California, Santa Barbara, CA, 93106, United States


Contact Information: adeyemiadeleye@umail.ucsb.edu; 805-893-5352


ABSTRACT

Over US$ 5.7 billion is spent annually to prevent and control marine biofouling, mainly with the use of antifouling paints. Antifouling paints typically contain copper compounds, which are toxic to a wide range of organisms. While many studies have quantified release of copper from antifouling paints, very little is known about the physicochemical state of released copper. For proper risk assessment of antifouling paints, characterization of copper released into water is necessary because the physicochemical state determines the metalís environmental fate and effects. In this study, we monitored release of different fractions of copper (dissolved, nano, and bulk) from a commercial copper-based antifouling paint. Release from painted wood and aluminum mini-bars that were submerged in natural waters was monitored for 180 days. Leachates contained both dissolved and particulate copper species. X-ray diffraction and X-ray photoelectron spectroscopy were used to determine the chemical phase of particles in the leachate. The amount of copper released was strongly dependent on water salinity, painted surface, and paint drying time. The presence of nanosized Cu2O particles was confirmed in paint and its leachate using electron microscopy. Toxicity of paint leachate to a marine phytoplankton was also evaluated.