Fish, Acute Toxicity Test (OECD TG 203)
The Fish Acute Toxicity Test according to OECD TG 203 is conducted to assess the short-term toxic effects of substances on fish species, providing key information for environmental hazard and risk assessment in aquatic ecosystems.
In this study, groups of fish are exposed to a range of concentrations of the test substance under controlled laboratory conditions for a duration of typically 96 hours. During the exposure period, the fish are observed at regular intervals for mortality and visible signs of distress or abnormal behavior.
The primary endpoint of the test is mortality, which is used to determine the median lethal concentration (LC₅₀), representing the concentration at which 50% of the test organisms die within the specified exposure period.
This test is a fundamental component of aquatic ecotoxicology, delivering essential data on the acute toxicity of chemicals to vertebrate aquatic organisms and supporting regulatory decision-making processes.
