Microcystin-LR concentrations (ppb) at the top, middle, and bottom of seawater tanks at two exposure concentrations (Tank 2 and Tank 31) and varying postexposure intervals.

1All samples from Tank 1 (seawater control) tested negative for microcystin-LR. All 3 tanks were flushed with fresh seawater starting 96 H postexposure).2nd = microcystin concentration was below minimum detection limits on liquid chromatography-tandem mass spectrophotometry.