A PSEUDANABAENA SPECIES FROM CASTAIC LAKE, CALIFORNIA, THAT PRODUCES 2-METHYLISOBORNEOL

Castaic Lake, a large reservoir in Southern California, experienced a two-month episode of the musty-smelling compound 2-methylisoborneol (M IB) in the fall of 1993. MIB levels in the water column reached or exc eeded 150 ng/l. A Pseudanabaena bloom coincided with the off-flavor ev ent. Fourteen odorous strains of the cyanobacterium were isolated, and eight of them were analyzed by gas-chromatographic methods to verify the presence of MIB in culture. The concentrations of MIB in culture r anged from 36 to 445 mu g/l: This is the first documented report, to o ur knowledge, of a major MIB episode in United States drinking water t hat was attributable to Pseudanabaena, an organism not generally recog nized as a taste-and-odor producer. (C) 1998 Elsevier Science Ltd. All rights reserved.