N,N'-hexamethylenebis(cinnamylideneamine)

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From October 04 to November 10, 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

2004

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

2008

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 100, 45.5, 20.7, 9.39 and 4.27 mg/l loading rate
- Sampling method: the test solutions were prepared by respective dilutions of a saturated solution. The respective quantities of test item were added to an empty glass vessel.

Vehicle:

yes

Remarks:

Water

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna (Straus, 1820)
- Breeding: Parental and young Daphnia held in 4 l glass aquaria (3 l medium) at 20 ± 2 °C, fed with a suspension of Desmodesmus subspicatus in Elendt M4 medium with an optical density OD680 of about 15 units
- Age: less than 24 h
- Feeding during test: no

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test temperature:

18 – 22 °C

pH:

7.0 ± 0.5

Conductivity:

<1.5 µS/cm

Nominal and measured concentrations:

100, 45.5, 20.7, 9.39 and 4.27 mg/l nominal loading rate
26.9, 11.9, 5.38, 2.38 and 1.06 mg/l measured concentration (27, 26, 26, 25 and 25 %, respectively, of the nominal loading rate)

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 ml beakers
- Material, size, headspace, fill volume: glass, 100 ml, with 50 ml of test medium
- Aeretion: no, during the test the beakers were covered with a glass plate to avoid evaporation and contamination of the test solutions with dust
- Renewal rate of test solution (frequency/flow rate): renewal of the test medium every 24 h
- No. of organisms per vessel: 20
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 3

OTHER TEST CONDITIONS
- Adjustment of pH: pH value adjusted to pH 7.0 ± 0.5
- Photoperiod:16 h photoperiod a day, supplied by overhead white fluorescent tubes

RANGE-FINDING STUDY
- Test concentrations: 1, 10 and 100 mg/l
- Results used to determine the conditions for the definitive study: at 1 mg/l 0 % of immobilization after 48 h, at 10 mg/l 17.5 % of immobilization, at 100 mg/l 70 % of immobilization

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

ca. 2.28 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% confidence limits: 0.854–5.93 mg/l

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

ca. 7.76 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% confidence limits: 6.08–9.13 mg/l

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

ca. 0.24 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

24 h

Dose descriptor:

NOEC

Effect conc.:

ca. 2 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

ca. 0.816 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% confidence limits: 0.058–1.70 mg/l

Duration:

24 h

Dose descriptor:

EC10

Effect conc.:

ca. 3.61 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% confidence limits: 1.35–5.01 mg/l

Test concentrations

The concentrations of Intercure 3 in the test medium were measured by HPLC analysis (LOQ 0.063 mg/l) at the beginning, after 24 h in the old and the fresh media, and after 48 h of exposure.
These analyses confirmed that the test item was partly dissolved and the concentrations were not stable over the whole 48 h period and were not within 80-120 % of the nominal loading rates.
The measured concentrations of the test item at the beginning of the test were 26.9, 11.9, 5.38, 2.38 and 1.06 mg/l (27, 26, 26, 25 and 25%, respectively, of the nominal loading rate) and 24.4, 7.11, 0.745, < LOQ and < LOQ (24, 16, 4 % respectively of the three highest nominal loadings; not applicable for the three lowest loadings) after 24 h in the old media.

After renewal of the test media at 24h, the concentrations were 17.0, 7.58, 3.25, 1.36 and 0.520 mg/l (17, 17, 16, 14 and 12%, respectively, of the loading rate), and 15.6, 2.64, > LOQ > LOQ and < LOQ (16 and 6% of the two highest nominal loadings; not determined for the three lowest) at the end of the test.

Therefore, the effective concentrations EC_x after 24h of exposure were assessed based on thegeometric mean of the measured concentrations at 0 and 24h; while the effective concentrations EC_x after 48h of exposure were assessed based onthe arithmetic mean of the two 24-h periods’geometric means of the measured concentrations.

Details on results

- After 24 h, following immobilization rates were observed: 100 % at 100 mg/l and 65 % at 45.5 mg/l. No significant effects (≤ 10 % immobilization) were observed at the loading rates of 20.7, 9.39 and 4.27 mg/l or in the blank controls;

- After 48 h, following immobilization rates were observed: 100 % at 100 mg/l, 100 % at 45.5 mg/l and 12.5 % at 20.7 mg/l. No significant effects (≤ 10% immobilization) were observed at the loading rates of 9.39 and 4.27 mg/l or in the blank controls.

Validity criteria fulfilled:

yes

Conclusions:

EC50 (48h) = 2.28 mg/l

Executive summary:

Method

The median effect concentration (EC50) and the no-effect concentration (NOEC) of Intercure 3 to Daphnia magna were investigated under semi-static exposure conditions over a period of 48 h, following OECD guideline 202.

Since the test item is readily biodegradable, the test was performed under semi-static exposure conditions with renewal of the test medium after 24 h of exposure. The test media were prepared by dilutions of a saturated stock solution.

The nominal loading rates corresponding to the different dilutions were100, 45.5, 20.7, 9.39 and 4.27 mg/l.

40 individual Daphnia divided into 2 test vessels were exposed to each concentration of the test item, and 60 Daphnia divided into 3 test vessels were used as blank controls.

The concentrations of Intercure 3 in the test medium were measured by HPLC analysis at the beginning and after 24 and 48 h of exposure. These analyses confirmed that the test item was partly dissolved, that the concentrations were not stable over the whole 48 h period and that they did not remain within 80-120 % of the nominal loading rates. Therefore, the effective concentrations EC_xwere assessed based on measured concentrations.

Results

The 48 h EC50 value of Intercure 3 of Daphnia magna was 2.28 mg/l. This value is based on measured concentrations.

All validity criteria were fulfilled.     

Description of key information

EC50 (48h) = 2.28 mg/l

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

48 mg/L

Additional information

The median effect concentration (EC50) and the no-effect concentration (NOEC) of Intercure 3 to Daphnia magna were investigated under semi-static exposure conditions over a period of 48 h, following OECD guideline 202.

Since the test item is readily biodegradable, the test was performed under semi-static exposure conditions with renewal of the test medium after 24 h of exposure. The test media were prepared by dilutions of a saturated stock solution.

The nominal loading rates corresponding to the different dilutions were 100, 45.5, 20.7, 9.39 and 4.27 mg/l.

40 individual Daphnia divided into 2 test vessels were exposed to each concentration of the test item, and 60 Daphnia divided into 3 test vessels were used as blank controls.

The concentrations of Intercure 3 in the test medium were measured by HPLC analysis at the beginning and after 24 and 48 h of exposure. These analyses confirmed that the test item was partly dissolved, that the concentrations were not stable over the whole 48 h period and that they did not remain within 80-120 % of the nominal loading rates. Therefore, the effective concentrations EC_xwere assessed based on measured concentrations. The 48 h EC50 value of Intercure 3 of Daphnia magna was 2.28 mg/l. This value is based on measured concentrations. All validity criteria were fulfilled.