Many of the accumulation experiments conducted take the rate of uptake as bio accumulation. But this uptake is essentially because of the abnormally elevated concentrations that these organisms are exposed to without choice, but they quickly depurate. The residual concentration left should be considered bio accumulated. if the experiments are done at ambient concentrations of chemicals and toxins then the uptake can be considered as bio accumulated as the condition is going to be stable for long time. Please guide me if my understanding is incorrect.