ColaLiquids DC5, DL, DM (Commercial names)Cocamide DIPA (INCI name)

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:

72 hours

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Freshwater Alga and Cyanobacteria, Growth Inhibition Test)

Version / remarks:

Test conditions according to SOP E203 based on OECD Guideline for testing of chemicals, Freshwater Alga and Cyanobacteria, Growth Inhibition Test reference 201 (2011).

Deviations:

yes

Remarks:

Light intensity and temperature variations - not deemed to be significant enough to cause any effects.

GLP compliance:

yes

Specific details on test material used for the study:

Name as supplied: ColaLiquid DC-5
Lot/Batch Number: 53467J16
Purity/Composition: CAS Number: 68855-69-6
Cocamide diisopropanolamine 84-88%
Glycerin 5-8%
Free Amine (DIPA) <5%
Chemex reference: ECO 161203

Analytical monitoring:

yes

Details on sampling:

Duplicate samples were taken at the start and end of the 72 hour exposure period. Samples were taken from remaining test media after filling test vessels for 0 hours and pooled replicate flasks for 72 hours.

Vehicle:

yes

Remarks:

nutrient growth medium

Details on test solutions:

Test concentrations: 0 (control), 0.32, 1.0, 3.2, 10, 32 and 100mg/l
Stock solutions were prepared for both the range-finding and definitive tests by addition of the test sample directly to nutrient growth medium in a volumetric flask of adequate volume. Calculated volumes of the stock solution were added to nutrient growth medium and made to volume to prepare the test concentrations and provide enough solution for testing and subsequent water quality measurements.
The test concentrations for both the range-finding test and definitive test were prepared separately by the addition of the test sample to nutrient growth medium in volumetric flasks of adequate volume to provide enough solution for testing and subsequent water quality measurements.

Test organisms (species):

Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum)

Details on test organisms:

Species: Pseudokirchneriella subcapitata strain: CCAP 278/4 received 22 April 2016.
Source: Culture Collection of Algae and Protozoa SAMS Ltd Scottish Marine Institute, OBAN, Argyll PA37 1QA. Scotland, United Kingdom
Culture conditions: Temperature: 20.9 – 21.7C.
Illumination: 6030 - 8100 lux continuous white light. Orbiting: set to 200pm.
Culture media: Deionised water with added nutrients according to OECD 201

Test type:

other: Orbital shaking: 200rpm (Required: 200-250rpm)

Water media type:

other: nutrient growth medium

Limit test:

yes

Total exposure duration:

72 h

Test temperature:

Temperature range within incubator throughout test: 20.4 – 23.3°C
(Required: 21-24±2°C)

pH:

Initial pH at 0 Hours: 7.48
pH range in control and test concentrations throughout test: 7.48 – 8.35

Reference substance (positive control):

yes

Remarks:

A separate reference study (ENV 11396) was run from 16 to 19 January 2017 using potassium dichromate (K1.0r2O7) as a means of checking the test procedure and sensitivity of the test species.

Key result

Duration:

72 h

Dose descriptor:

other: ErC50

Effect conc.:

3 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

growth rate

Key result

Duration:

72 h

Dose descriptor:

other: EyC50

Effect conc.:

1.37 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

biomass

Key result

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

other: growth rate and biomass

Key result

Duration:

72 h

Dose descriptor:

LOEC

Effect conc.:

3.2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

growth rate

Details on results:

The algal cells were examined microscopically during the determination of cell concentration. All cells within the control and test concentrations appeared normal, no abnormalities were observed

Validity criteria fulfilled:

yes

Conclusions:

The 48 hour EC(r)50 and EC(y)50 of ColaLiquid DC-5 to Pseudokirchneriella subcapitata were 7.88mg/l and 2.33mg/l respectively.
The 72 hour EC(r)50 and EC(y)50 of ColaLiquid DC-5 to Pseudokirchneriella subcapitata were 3.0mg/l and 1.37mg/l respectively.
The 0 to 72-hour NOEC(r) was 1.0mg/l and the 0-72 hour LOEC was 3.2mg/l.
The algal cells were examined microscopically during the determination of cell concentration. All cells within the control and test concentrations appeared normal, no abnormalities were observed.
All validity criteria for the definitive test were met. The water quality measurements and incubation conditions were within accepted limits

Description of key information

The 48 hour EC(r)50 and EC(y)50 of ColaLiquid DC-5 to Pseudokirchneriella subcapitata were 7.88mg/l and 2.33mg/l respectively.

The 72 hour EC(r)50 and EC(y)50 of ColaLiquid DC-5 to Pseudokirchneriella subcapitata were 3.0mg/l and 1.37mg/l respectively.

The 0 to 72-hour NOEC(r) was 1.0mg/l and the 0-72 hour LOEC was 3.2mg/l.

The algal cells were examined microscopically during the determination of cell concentration. All cells within the control and test concentrations appeared normal, no abnormalities were observed.

All validity criteria for the definitive test were met. The water quality measurements and incubation conditions were within accepted limits

Key value for chemical safety assessment

EC50 for freshwater algae:

1.37 mg/L

EC10 or NOEC for freshwater algae:

1 mg/L