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Evaluation of the Hazard of Microcystis Blooms for Human Healththrough Fish Consumption

Human exposure to the cyanobacterial toxin microcystin occurs through  drinking water and recreational contact in waters experiencing  Microcystis blooms, but dietary exposure may be another route not  widely investigated.  As a hepatotoxin, microcystin has been  documented to accumulate in the livers of many animals, but the degree  to which this toxin is present in the edible muscle tissue of popular  Great Lakes recreational fish (e.g., yellow perch and bluegill) is not  known.  The main goal of this project is to address the potential for  human exposure to cyanobacterial toxins through measurement of  microcystins in wild-caught fish and the secondary goal is to conduct  laboratory experiments to investigate the kinetics of toxin  accumulation in fish tissue.  The main goal was addressed using data  from Lake Erie during the summer 2  6 and from Muskegon Lake in the  summer 2  7, which suggested that while microcystin concentrations in  livers could be a human health risk, even during periods of high  microcystin concentration in the water column, microcystin  concentrations in the muscle tissue of fish of edible size are not  high enough to be an acute threat to human health.      The rate at which a fish accumulates and depurates microcystin has  significant relevance to knowing what period during and after a bloom  a fish might contain microcystin in its tissues.  To address the  kinetics of microcystin accumulation, one experiment was conducted in  the summer 2  7 and showed that the peak toxin concentrations in perch  liver and muscle was at 8 hrs after exposure and the decreased rapidly  by 12 hrs.  For the summer 2  8, we propose to repeat this experiment  with a greater number of replicates, increased sampling in the 12 hr  time frame and a range of microcystin dosing concentrations in order  to build a better mass balance model for microcystin accumulation in  fish liver and muscle.

In progress
Start Date
End Date
Scope of Study
Field Investigation
Scale of Phenomena
Impact of Pollutants
Exotic Species
Toxic Organics
Natural Ecological Processes
Lake Basin Connecting Channels
Lake Erie
Resource Being Monitored
Human Health
Ecosystem Effects
Nutrient / Contaminant Cycles
Socio-economic Consideration and Analysis
Human Health Aspects

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