Geosmin (GSM) and 2-methylisoborneol (MIB) are semi-volatile compounds produced by cyanobacteria in surface waters. These compounds present problems to the drinking water industry and in aquaculture because they can taint water and fish producing an earthy-musty flavour. This paper presents an initial study on the use of TiO2 photocatalysis for the destruction of these compounds in water. The process proved effective with the complete destruction of MIB and GSM being achieved within 60 min. These results suggest that TiO2 Photocatalysis will be a successful method for removal of taint compounds from potable water supplies and fish farms. (C) 2003 Elsevier Science B.V. All rights reserved.