Reaction mixture of hydrogenated tallow alkyl amines with sebacic acid and lithium hydroxide

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1999-09-22 to 1999-12-07

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

Version / remarks:

dated December 29, 1992

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Version / remarks:

adopted June 7, 1984.

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Vehicle:

no

Details on test solutions:

A supersaturated stock suspension of the test substance with a nominal concentration of 100 mg/L was prepared by dosing 100 mg of the test substance into 1 L test water. No auxiliary solvent or emulsifier was used. The test substance was mixed into the test water as homogeneously as possible by ultrasonic treatment for 15 minutes and intense stirring. The supersaturated stock suspension was therefore stirred on a magnetic stirrer at room temperature in the dark over about 66 hours to dissolve, respectively disperse a maximum concentration of the test substance in test water.
The stock suspension of the test substance was filtered through a cellulose-nitrate filter with a defined pore size of 0.2 µm. The filtrate of the stock suspension with dissolved test substance was used as the highest concentrated test medium. Adequate volumes of the stock suspension filtrate were diluted with test water to prepare the test media of following dilutions: dilution 1:2, 1:4, 1:8 and 1:16.

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Strain: No. 86.81 SAG
- Source: The algae were supplied by the "Sammlung von Algenkulturen, Pflanzenphysiologisches Institut der Universität Göttingen", 37073 Göttingen, Germany

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Hardness:

24 mg CaCO3/L

Test temperature:

23 - 24°C

pH:

7.8 to 8.2 at test start
9.3 to 10.4 at test end

Details on test conditions:

TEST SYSTEM
- Test vessel: Erlenmeyer flasks of 50 mL volume with 50 mL test medium
- Initial cells density: 10.000 algal cells per mL test medium
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 6

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

78.2 mg/L

Nominal / measured:

nominal

Basis for effect:

biomass

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

50 mg/L

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

50 mg/L

Basis for effect:

biomass

Details on results:

No concentrations of the dissolved components of the test substance (EC: 433-100-1) can be given, because no analytical method for dose verification is available. Therefore, the biological results of the algae test are based on the nominal concentration of 100 mg/L which was used to prepare the stock solution of the filtrate and to nominal concentrations of the test substance in the dilutions of the filtrate.

Validity criteria fulfilled:

yes

Conclusions:

The test substance (EC: 433-100-1) was tested for toxicity to aquatic freshwater algae in a 72 h-growth inhibition test according to EU method C.3 and OECD guideline 201. The ecotoxicity data indicates the test substance shows some toxicity to algae below the limit of its solubility.

Executive summary:

The test substance (EC: 433-100-1) was assessed in an aquatic toxicty test to algae according EU-method C.3 and OECD guideline 201. Due to the low water solubility limit of the test substance a filtrate of a supersaturated stock suspension of nominal 100 mg/L was prepared. The filtrate of the stock suspension with dissolved test substance was used as the highest concentrated test medium. Adequate volumes of the stock suspension filtrate were diluted with test water to prepare the test media of following dilutions: dilution 1:2, 1:4, 1:8 and 1:16. Additionally, a control was tested in parallel. The 72-hour NOEC for the growth rate and for biomass was determined to be nominal 50 mg/L (1:2 dilution). The 72- hour EC50 for the growth rate was calculated to be >100 mg/L and for biomass 78.2 mg/L based on nominal concentrations.

Description of key information

The test substance (EC: 433-100-1) was assessed in an aquatic toxicity test to algae according EU-method C.3 and OECD guideline 201. Due to the low water solubility limit of the test substance a filtrate of a supersaturated stock suspension of nominal 100 mg/L was prepared. The filtrate of the stock suspension with dissolved test substance was used as the highest concentrated test medium. Adequate volumes of the stock suspension filtrate were diluted with test water to prepare the test media of following dilutions: dilution 1:2, 1:4, 1:8 and 1:16. Additionally, a control was tested in parallel. The 72-hour NOEC for the growth rate and for biomass was determined to be nominal 50 mg/L (1:2 dilution). The 72- hour EC50 for the growth rate was calculated to be >100 mg/L and for biomass 78.2 mg/L based on nominal concentrations.

 

Key value for chemical safety assessment

EC50 for freshwater algae:

100 mg/L

Additional information

The test substance (EC: 433-100-1) was assessed in an aquatic toxicty test to algae according EU-method C.3 and OECD guideline 201. Due to the low water solubility limit of the test substance a filtrate of a supersaturated stock suspension of nominal 100 mg/L was prepared. The filtrate of the stock suspension with dissolved test substance was used as the highest concentrated test medium. Adequate volumes of the stock suspension filtrate were diluted with test water to prepare the test media of following dilutions: dilution 1:2, 1:4, 1:8 and 1:16. Additionally, a control was tested in parallel. The 72-hour NOEC for the growth rate and for biomass was determined to be nominal 50 mg/L (1:2 dilution). The 72- hour EC50 for the growth rate was calculated to be >100 mg/L and for biomass 78.2 mg/L based on nominal concentrations.