Foodweb transfer, accumulation, and depuration of microcystins, a cyanobacterial toxin, in pumpkinseed sunfish (Lepomis gibbosus).
Zooplankton accumulate microcystins (MC), a potent cyanobacteria toxin, and therefore may act as vectors of the toxin up the aquatic food web; however this transfer has not yet been quantified. In addition there is a lack of information regarding fish's ability to metabolize MC when administered a low dose over a longer period of time. We monitored MC concentrations in three levels of an aquatic food web: phytoplankton, zooplankton, and sunfish (Lepomis gibbosus). Bosmina appeared to be both a major accumulator of MC in zooplankton and the major vector of MC to sunfish. In an accumulation experiment, sunfish were brought into the laboratory and fed MC-rich zooplankton pellets (50 ng MC kg(-1)d(-1)) for 9 days. Zooplankton directly transferred MC to sunfish, resulting in liver and muscle tissue accumulation. However, after 6 days of accumulation fish significantly decreased concentrations in their liver and muscle tissue, indicating the induction of a detoxification and excretion pathway. Sunfish retained MC in their liver and muscle tissue, showing no significant changes in toxin concentration over 2 weeks of fasted depuration.
Smith
Juliette L
JL
Faculty of Environmental and Forest Biology, State University of New York, Syracuse, College of Environmental Science and Forestry, 1 Forestry Drive, Syracuse, NY 13210, USA. jlsmit19@syr.edu
Haney
James F
JF
D000818:Animals; D001427:Bacterial Toxins / Q000032:analysis / Q000493:pharmacokinetics*; D000458:Cyanobacteria / Q000378:metabolism*; D017753:Ecosystem; D020387:Food Chain; D008658:Inactivation, Metabolic; D008099:Liver / Q000378:metabolism; D052998:Microcystins; D018482:Muscle, Skeletal / Q000378:metabolism; D010456:Peptides, Cyclic / Q000032:analysis / Q000493:pharmacokinetics*; D010473:Perciformes / Q000378:metabolism*; D010839:Phytoplankton / Q000737:chemistry / Q000378:metabolism; D010933:Plankton / Q000737:chemistry / Q000378:metabolism*; D015048:Zooplankton / Q000737:chemistry / Q000378:metabolism
D001427:Bacterial Toxins; D052998:Microcystins; D010456:Peptides, Cyclic; C078588:microcystin