Choline chloride

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:

1989-08-17 - 1989-08-21

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The experiment was conducted according to the national guideline DIN 38412 L9. No information about GLP compliance is reported. Not all details are described in test report; however, available data indicate that the study meets scientific principles.

Qualifier:

according to guideline

Guideline:

other: DIN 38412 L9

GLP compliance:

not specified

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material: No surrogate or analogue material was used.

Analytical monitoring:

no

Details on sampling:

Samples were taken and evaluated after 72 and 96h. Fluorometric determination of the cell count every 24 h.

Vehicle:

no

Details on test solutions:

The stock solution contained 100 % of the test substance. No solvents were used, since the water solubility is unlimited for the test substance.

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Strain: Chodat
- Source: Göttingen algae collection, SAG 86.81

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

No post exposure observation period described.

Hardness:

No details available.

Test temperature:

21.5 °C

pH:

0 mg/L: 8.27 (start), 8.32 (end)
10000 mg/L: 8.06 (start), 8.08 (end)
25000 mg/L: 8.08 (start), 7.96 (end)
50000 mg/L: 8.10 (start), 7.79 (end)
100000 mg/L: 8.05 (start), 7.54 (end)
250000 mg/L: 8.03 (start), 7.06 (end)
500000 mg/L: 8.04 (start), 6.59 (end)

Dissolved oxygen:

No details available.

Salinity:

Not applicable.

Nominal and measured concentrations:

0, 10, 25, 50, 100, 250 and 500 mg/L

Details on test conditions:

TEST SYSTEM
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

EFFECT PARAMETERS MEASURED
- Chlorophyll measurement: Fluorometric (impulse fluorometer)
- Spectrophotometric scan: 300 - 780 nm

RANGE FINDING STUDY
- Test concentrations: 5, 50, 500 mg/L

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

> 500 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 500 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

> 500 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 500 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

96 h

Dose descriptor:

EC10

Effect conc.:

> 500 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

> 500 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Duration:

96 h

Dose descriptor:

EC10

Effect conc.:

> 500 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

> 500 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Details on results:

No further details are reported.

Results with reference substance (positive control):

Not reported.

Reported statistics and error estimates:

Tallarida, R.J., Jakob, L.S. (1979): The Dose-Response Relation in Pharmacology pp. 98-103, published by Springer.

Validity criteria fulfilled:

yes

Remarks:

Scientific criteria for acute toxicity testing to aquatic algae seemed to be fulfilled.

Conclusions:

The study report describes a valid study, conducted according to a national guideline (DIN 38412 L9). No information about GLP compliance available. Available data confirm that the experiment was well-performed. The test substance was not toxic to aquatic algae (EC50 > 500 mg/L) up to an exposure duration of 96 h.

Executive summary:

Scenedesmus subspicatus (new name: Desmodesmus subspicatus) was used in an experiment according to the German guideline DIN 38412 L9 in order to test the toxicity of Choline chloride towards freshwater algae (BASF AG, 1989). Test concentrations were chosen as followed: 0 (control), 10, 25, 50, 100, 250 and 500 mg/L.

Potassium dichromate served as reference substance. Samples were taken and evaluated after 72 and 96h. A fluorometric determination of the cell count was performed every 24 h. As results, the EC50(72h) and EC50(96h) resulted in values > 500 mg/L based on growth rate as well as on biomass, respectively. The same applies to the determined EC10 values after 72 h and 96 h.

Description of key information

No toxicity observed even at highest concentration level tested.
Scenedesmus subspicatus_DIN 38412 L9:

ErC10(72h) > 500 mg/L,

EbC10(72h) > 500 mg/L,

ErC50(72h) > 500 mg/L,

EbC50(72h) > 500 mg/L,

ErC10(96h) > 500 mg/L,

EbC10(96h) > 500 mg/L,

ErC50(96h) > 500 mg/L,

EbC50(96h) > 500 mg/L

Key value for chemical safety assessment

EC50 for freshwater algae:

500 mg/L

EC10 or NOEC for freshwater algae:

500 mg/L

Additional information

Scenedesmus subspicatus (new name: Desmodesmus subspicatus) was used in an experiment according to the German guideline DIN 38412 L9 in order to test the toxicity of Choline chloride towards freshwater algae (BASF AG, 1989). Test concentrations were chosen as followed: 0 (control), 10, 25, 50, 100, 250 and 500 mg/L.

Potassium dichromate served as reference substance. Samples were taken and evaluated after 72 and 96h. A fluorometric determination of the cell count was performed every 24 h. As results, the EC50(72h) and EC50(96h) resulted in values > 500 mg/L based on growth rate as well as on biomass, respectively. The same applies to the determined EC10 values after 72 h and 96 h.