Low → high body burden
This simulator models how a persistent, fat-soluble contaminant — the kind of pollutant behind real-world mercury and PCB advisories — accumulates as it moves up a four-level aquatic food chain: phytoplankton, zooplankton, small fish and a top predator fish. Each level runs its own one-compartment toxicokinetic equation, taking in the contaminant directly from water and from its diet while losing it at a first-order elimination rate that gets slower at higher trophic levels. The 2D view renders the chain as four stacked tanks joined by flux arrows whose thickness and animated flow speed are read straight off that tick's uptake terms, with a live scrolling strip chart tracking every level's concentration — and the trophic magnification factor — across simulated time. Adjust the elimination rate, ambient water concentration and dietary assimilation efficiency to see how fast and how far biomagnification compounds.