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 aquatic invertebrates

Description of key information

Freshwater: NOEC 0.009 mg/L, LOEC 0.018 mg/L, life-cycle toxicity, Daphnia magna, EPA OPP 72-4, EPA 540/9-86-141, ASTM E1193-87, Roberts & Swigert 1997
 
Marine Study:
No data available

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.009 mg/L

Additional information

The long-term toxicity to aquatic invertebrates was determined in a life-cycle toxicity study performed using Daphnia magna. The test was conducted in line with GLP and in accordance with the standardised guidelines EPA OPP 72-4, EPA 540/9-86-141 and ASTM E1193-87. Daphnids were exposed to the test material at measured concentrations of 0.009, 0.018, 0.036, 0.07 and 0.13 mg a.i./L under flow-through freshwater conditions for 21 days. Survival, clinical signs, reproduction and growth were monitored in adults and offspring to determine the acute toxicity.

Under the conditions of the test, growth was shown to be the most sensitive biological parameter to exposure of the test material. A statistically significant (p<0.05) reduction in mean dry weight was observed at 0.018 mg a.i./L. At concentrations ≥ 0.036 mg a.i./L growth was shown to decline with increasing concentration, however as survival was affected at these concentrations, these values could not be included in the statistical analyses for growth. Based on growth data the LOEC was determined to be 0.018 mg a.i./L and the NOEC was determined to be 0.009 mg a.i./L. Reproductive performance was shown to be affected at concentrations ≥0.036 mg a.i./L but the results from the 0.009 and 0.018 mg a.i./L treatment groups was not statistically significant to the pooled controls. Statistical analysis could not be performed on higher concentrations due to significant effects on adult survival but the observed response suggests a treatment-related response on reproduction. Percentage mortality was statistically different (p<0.05) from the pooled controls at 0.036, 0.07 and 0.13 mg a.i./L, where mortality reached 39, 79 and 86%, respectively. Based on mortality data alone, the NOEC was determined to be 0.018 mg a.i./L and the LOEC was determined to be 0.036 mg a.i./L.

Based on the most sensitive data the overall NOEC and LOEC for toxicity during a life-cycle toxicity test were determined to be 0.009 and 0.018 mg a.i./L, respectively. The maximum acceptable toxicant concentration was determined to be 0.013 mg a.i./L, calculated as the geometric mean of the NOEC and LOEC.

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 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.