isostearic acid monoisopropanolamide

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 June 06, 2001 to June 17, 2011

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)

Deviations:

yes

Remarks:

regarding DOC measurements in the pre-test

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

yes

Remarks:

regarding DOC measurements in the pre-test

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Remarks:

total organic carbon (TOC) analysis

Details on sampling:

Analytical report
Three 400 mL beakers were prepared for TOC analysis. One was filled up with 300 mL of M4 medium (control); the two others were filled up each with 300 mL of the nominal concentrations: 10 and 20 mg/L. TOC determinations (in triplicate) were provided at 0, 24 and 48h after application.

Vehicle:

no

Details on test solutions:

Based on a pre-test, the test substance was identified as poorly soluble in M4 medium. 1.25, 2.5, 5.0, 10 and 20 mg test substance were diluted in 1000 mL M4 medium and stirred (300 rpm) 24h. The test solutions were then filtered through a filter paper circle. The control was treated the same way.

Test organisms (species):

Daphnia magna

Details on test organisms:

Common name: Daphnia magna (Crustacea, Cladocera) (Straus), descended from a population received from "Landesumweltant (NRW)", Dusseldorf, Germany
Number of animals: 15-20 per beaker
Age: <24h
Temperature: 20 +/- 2°C
Artificial light-dark cycle of 16 to 8 hours
Feeding during test: algae (Desmodesmus subspicatus)
Holding and test medium: Elendt-Schneider M4 medium

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

2.2-3.2 mmol/L (total)

Test temperature:

20 +/- 2°C

pH:

7.5-8.5

Dissolved oxygen:

TOC: < 2 mg/L

Salinity:

-

Conductivity:

500-700 µS/cm

Nominal and measured concentrations:

0, 1.25, 2.5, 5.0, 10 and 20 mg/L (nominal)

Details on test conditions:

50 mL glass beakers (with 30 mL) solution were used. (The test beakers were not aerated because of risk of floating daphnia to the water surface). Five daphnia were distributed per vessel for each concentration and for the control.

Reference substance (positive control):

no

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

ca. 7.4 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

ca. 5 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

Analytical measurements:
Recovery of TOC in test substance preparations after 24 and 48h was 86 to 122% of TOC content of the nominal test concentrations (10 and 20 mg/L) at 0h. Therefore, the EC values were based on the nominal concentrations.
NB. The test substance preparation of 20 mg/L showed slight turbidity. After filtration all test substance concentrations were present as clear solutions.
Biological results:
The results showed that the test substance induced statistically significant immobilization to the exposed Daphnia from nominal 10 mg/L upwards within 48h. No abnormal behaviour or appearance of Daphnia was observed during the test.

Reported statistics and error estimates:

EC50 value with 95% confidence interval, percental immobility and the NOEC after 24 and 48 h were calculated as well as statistical evaluations.

None.

Validity criteria fulfilled:

yes

Conclusions:

Under the study conditions, the nominal 48 h EC50 and NOEC were determined to be 7.4 and 5 mg/L, respectively.

Executive summary:

A study was conducted to determine the short term toxicity of the test substance, IsoC18 MIPA (80% active), to Daphnia magna according to OECD Guideline 202 and EU Method C.2, in compliance with GLP. Based on the findings of a range finding test, five daphnids per concentration (5 per vessel) were exposed to a blank control and to nominal test substance concentrations of 1.25, 2.5, 10.0 and 20.0 mg/L for 48 h under static conditions. The test substance was first diluted in 1000 mL M4 medium, then stirred (300 rpm) for 24h and filtered through a filter paper circle. Test substance concentrations were verified analytically with TOC analysis at t= 0 h, t= 24 h and t=48 h. Recovery of TOC after 24 and 48 h was 86 to 122% of TOC content of the nominal test concentrations at 0 h. Therefore, the EC values were based on nominal concentrations. The test substance induced statistically significant immobilization to the exposed Daphnia from 10 mg/L. No abnormal behaviour or appearance of Daphnia was observed during the test. Under the study conditions, the nominal 48 h EC50 and NOEC were determined to be 7.4 and 5 mg/L, respectively (Wehrhahn, 2011).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

7.4 mg/L

Additional information

A study was conducted to determine the short term toxicity of the test substance, IsoC18 MIPA (80% active), to Daphnia magna according to OECD Guideline 202 and EU Method C.2, in compliance with GLP. Based on the findings of a range finding test, five daphnids per concentration (5 per vessel) were exposed to a blank control and to nominal test substance concentrations of 1.25, 2.5, 10.0 and 20.0 mg/L for 48 h under static conditions. The test substance was first diluted in 1000 mL M4 medium, then stirred (300 rpm) for 24h and filtered through a filter paper circle. Test substance concentrations were verified analytically with TOC analysis at t= 0 h, t= 24 h and t=48 h. Recovery of TOC after 24 and 48 h was 86 to 122% of TOC content of the nominal test concentrations at 0 h. Therefore, the EC values were based on nominal concentrations. The test substance induced statistically significant immobilization to the exposed Daphnia from 10 mg/L. No abnormal behaviour or appearance of Daphnia was observed during the test. Under the study conditions, the nominal 48 h EC50 and NOEC were determined to be 7.4 and 5 mg/L, respectively (Wehrhahn, 2011).