Degradation potential of musty odour in a drinking water source by a biofilm method

The purpose of this study was to evaluate the degradation potential of 2-methylisoborneol (MIB) and its producer by a biofilm process. The cyanobacteria Phormidium tenue was isolated from the biofilm in a biological treatment facility for water supply. MIB was efficiently removed by the facility and the removal ratio was about 70% during the investigation period of 2 years. There was a favourable correlation between the removal rate of P. tenue and the number of micro-organisms, especially ciliates on the biofilm. But a high rise of pH value due to sudden proliferation of cyanobacteria induced a reduction in removal of P. tenue and MIB. It was found that the ciliate protozoa and pH value were very important factors for the removal of MIB and P. tenue.