Fate and Persistence of Particulate and Dissolved Microcystin-LA from Microcystis Blooms

摘要: ABSTRACTFew studies have estimated fate and persistence of the hepatotoxic microcystins (MCs) in situ, making ecological human health risk assessments challenging. We determined MC congeners during 2 years Microcystis blooms a small, shallow, closed-basin lake Ontario, Canada. In situ half-lives were compared to estimates obtained vitro under controlled temperature light. The produced elevated microcystin-LA (MC-LA) (maximum ∼4.2 mg L−1) with minor concentrations MC-LR, -RR, -YR. Dissolved MC-LA declined more slowly persisted longer than particulate (total 1.5–8.5 days) shorter 6.8–60.0 days). Half-lives 2010 two eight times 2009, likely due differences bloom phenology species/strain composition. vitro, higher (4°C → 25°C dark), irradiance (dark 45 260 μE m−2s−1 at 25°C) accelerated dissolved decline, respe...