N-ethyl-4-[[4-(ethylamino)-m-tolylphenyl][4-(ethylimino)-3-methylcyclohexa-2,5-dien-1-ylidene]methyl]-m-toluidine monoacetate

Endpoint summary

Additional information

Short term toxicity to aquatic invertebrates

In the acute immobilisation test with Daphnia magna (STRAUS), the effects of the test item were determined according to OECD 202 (2004), equivalent to the Council Regulation (EC) No. 440/2008 Method C.2 (2008) (BASF SE, 2015).

The study was conducted under semi-static conditions over a period of 48 hours with a saturated solution with a nominal loading of 1000 µg/L of the test item and further four dilution levels in a geometric series with a separation factor of 2 (nominal loading rates of 6.25 to 50.0 %). A saturated solution with a nominal loading of 1000 µg/L of the test item was prepared with dilution water one day before the start of the exposure intervals (at -24 and 0 hours) and was used for testing and as stock solution for the preparation of all further tested dilution levels. Further dilution levels were prepared by diluting the saturated solution with dilution water. The tested solutions were visually clear throughout the exposure period with a concentration related light violet colour. Twenty daphnids were exposed to each concentration level and the control. The concentrations of the test item were analytically verified via LC-MS/MS. The measured concentrations of the test item at the start of the exposure intervals were within the range of 38.7 to 681 µg/L (0 hours) and 40.4 to 622 µg/L (24 hours) and reflect the dilution factor of 2. At the end of the exposure intervals (24 and 48 hours), the measured concentrations were within the range of 63 to 86 % of the initially measured concentrations. Since the measured test item concentrations did not remain within ± 20 % of the initially measured concentrations, the effect values are based on the geometric mean measured concentrations of the test item calculated to be: 34.8, 62.1, 134, 283, 525 µg/L. The water quality parameters (i.e. pH-value and dissolved oxygen concentration), measured at the start (0 and 24 h) and at the end of the exposure intervals (24 and 48 h), were within the acceptable limits. The validity criteria of the test guidelines were fulfilled.

Based on the geometric mean measured concentrations of the test item, the 48h-EC50 for Daphnia magna was 73.5 µg/L (95 % confidence limits: 68.5 - 83.1 µg/L).

Toxicity to aquatic plants

The effects of the test item on the growth of the monocotyledon species Lemna gibba were determined according to the principles of OECD 221 (BASF SE, 2015). A saturated solution with a nominal loading of 100 mg/L of the test item was prepared with dilution water two days prior to the start of the exposure and before each renewal of the test solutions. It was used for testing and as stock solution for the preparation of all further tested dilution levels.

A semi-static exposure over 7 days was carried out. Based on a preliminary test, the saturated solution and five dilution levels were tested in a geometrical series with a dilution factor of 3.16: 0.316 - 1.00 - 3.16 - 10.0 - 31.6 - 100 %. Three replicates were investigated for each test concentration and six for the control. Frond numbers were assessed on days 0, 2, 5 and 7. Environmental parameters (light, pH and temperature) were within the acceptable limits. The validity criteria of the test guideline were fulfilled. The concentrations of the test item and the control were analysed via LC-MS/MS analysis at the beginning and end of the exposure and at every renewal day. Freshly prepared and old media were analysed. The measured concentrations of the test item in the old test media were in the range of 2 to 48 % of the initially measured values (except the lowest concentration of the 2nd exposure interval where the measured value was below LOQ).

Based on the geometric mean measured concentrations of the test item a 7d-ErC50 and 7d-ErC10 of 0.0521 mg/L and < 0.0034 mg/L was determined based on dry weight.