1-(allyloxy)-2-methyl-1-oxopropan-2-yl 2-chloro-5-[3-methyl-2,6-dioxo-4-(trifluoromethyl)-3,6-dihydropyrimidin-1(2H)-yl]benzoate

Long-term toxicity to fish

Description of key information

Freshwater: NOEC 11 µg a.i./L, LOEC 22 µg a.i./L, early life-stage toxicity, Oncorhynchus mykiss, EPA OPP 72-4, EPA 540/9-86-138, ASTM E1241-88a, Palmer & Krueger 1998

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

11 µg/L

Additional information

The long-term toxicity to fish was determined in an early-life stage toxicity study performed using Oncorhynchus mykiss.The test was conducted in line with GLP and in accordance with the standardised guidelines EPA OPP 72-4, EPA 540/9-86-138 and ASTM E1241-88a. Embryos were exposed to the test material at measured concentrations of 5.3, 11, 22, 43 and 90 µg a.i./L under flow-through freshwater conditions for 28 days. Embryos, larval and fish were observed for fertilisation success, hatching success, time to hatch, time to swim-up of the larvae and post-hatch survival, clinical signs of toxicity and growth.

Under the conditions of the test no apparent treatment related effects were observed at concentrations ≤ 11 µg a.i./L in comparison to the pooled controls. This conclusion was based on the following parameters; time to hatch, hatching success, time to swim-up, larval survival, fry survival and growth. In comparison to the control significant (p ≤ 0.05) reductions in larval survival from hatch until thinning, time to swim-up and growth at termination were observed in the 22 µg a.i./L exposure group. At the highest concentrations tested, 43 and 90 µg a.i./L, a significant (p ≤ 0.05) reduction in comparison to the controls was observed for hatching success, time to swim-up, larval and fry survival and growth.

Therefore the most sensitive parameters were identified as larval survival, time to reach swim-up and growth. Consequently the LOEC was determined to be 22 µg a.i./L and the NOEC 11 µg a.i./L based on the most sensitive data. Based on the LOEC and NOEC the MATC was calculated to be 16 µg a.i./L. The study is considered to be reliable, relevant and adequate for risk assessment purposes.

The study was performed to a high standard, in line with GLP and standardised guidelines. Accordingly the study has been assigned a reliability score of 1 in line with the principles for assessing data quality set out in Klimisch (1997). The available data are deemed to be relevant, reliable and adequate for the purposes of risk assessment.