Organophosphorus diazinon induced toxicity in the fish anguilla angvilla L.

1. Acute toxicity effects of diazinon on European eel (Anguilla anguilla) were examined using short-term exposures in static conditions.2. The lc₅₀ values found were: 0.16, 0.11, 0.09 and 0.08 mg/1 at 24, 48, 72 and 96 hr exposure, respectively.3. Eels were exposed to 0.056 mg/l of diazinon and the bioaccumulation and elimination of this insecticide in liver, muscle, gill and blood tissues were studied.4. BCF were 800 in liver, 1600 in muscle tissue and 2300 and 2730 in gill and blood tissue, respectively.5. The BCF₁ were 0.30 for liver, 0.60 for muscle and 0.84 for gill. Higher accumulation capacity of the gill was observed for the first hour of exposure.6. Diazinon elimination from the selected tissues was rapid, diazinon levels were not detected in any tissue after 24 hr in clean water.7. The excretion rate constants (K₂) of this insecticide were 0.023 hr⁻¹ for liver, 0.005 hr⁻¹ for gill and 0.019 ⁻¹ for muscle.8. Diazinon half-lives were calculated as 30.6, 32.2 and 38.3 hr for liver, muscle and gill, respectively.