Ethanone, 2,2-dichloro-1-[5-(2-furanyl)-2,2-dimethyl-3-oxazolidinyl]-

Short-term toxicity to fish

Description of key information

The 96 h LC50 and NOEC of MON 13900 to bluegill sunfish (Lepomis macrochirus) under static conditions were determined to be 4.6 and 2.9 mg/L (mean measured concentrations).

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

4.6 mg/L

Additional information

A study was conducted to determine the 96 h acute toxicity of MON 13900 to bluegill sunfish (Lepomis macrochirus) in a static test system according to OECD Guideline 203, EU Method C.1 and EPA Guideline OPP 72-1 in compliance with GLP. Groups of ten fish were exposed for 4 d in hard blended water (160 to 180 mg/L as CaCO3) to nominal concentrations of 0 (controls), 1.9, 3.8, 7.5, 15 and 30 mg/L. The test media were prepared 24 h before introduction of the fish and samples were taken at 0 and 96 h for analysis of the test substance by GLC. Behavioural/sublethal effects observed at dose levels of 5.6 mg/L and above included lying on the bottom, quiescence, laboured respiration, surfacing, loss of equilibrium and dark discoloration. Dissolved oxygen concentrations ranged from 62 - 98% of the air saturation value and pH from 8.0 - 8.5. The temperature was 22°C. The mean measured concentrations in test media were 1.4, 2.9, 5.6, 12 and 20 mg/L (67 - 80% of nominal values) and remained stable over the 96 hour test period. A brown precipitate was observed on the base of all the test vessels except controls and the amount of precipitate increased with increasing test substance concentrations. Based on mean measured concentrations, the 96 h LC50 to bluegill sunfish under static conditions was determined to be 4.6 mg/L (95% confidence limits of 2.9 to 12 mg/L). The NOEC was 2.9 mg/L, based on mortality and sublethal effects observed at 5.6 mg/L.