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Lethal Dose Fifty (LD50)
The dose or concentration of a chemical that causes death in 50% of the population of a paticular species
Toxicity Threshold
The lowest dose where an effect starts to occur on a paticular species.
Dose response curve
A curve describing the effect on an organism or mortality rate in a population based on the dose of a paticular toxin or drug.
Effective dose 50 (ED50)
The dose concentration of a toxin or chemical that causes a non-lethal effect in 50% of the population being tested.
Acute vs. Chronic studies
An acute study is a short term isolated study, while a chronic study measures the effects of a dose-response in the long term and the ecological effects.