Dodecyltrimethylammonium bromide

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

other: Publication in literature

Adequacy of study:

other information

Study period:

2011

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Justification for type of information:

Data considered acceptable for purpose of classification of an intermediate substance under SCC.

Data source

Reference

Reference Type:

publication

Title:

Quantitative structure-activity relationship (QSAR) study of toxicity of quaternary ammonium compounds on Chlorella pyrenoidosa and Scenedesmus quadricauda

Author:

Jing, G., Zhou, Z., Zhuo, J.

Year:

2012

Bibliographic source:

Chemosphere 86 (2012), pp. 76-82

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

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

Version / remarks:

Not specified

Deviations:

yes

Principles of method if other than guideline:

- Exposure period was 96 hours instead of 72 hours
- Test solutions were not analysed to determined actual exposure concentrations
- No effect concentration for growth rate was calculated
- Only limited information on the study design was provided.

GLP compliance:

no

Remarks:

Publication in literature

Test material

Test material information

Constituent 1

Reference substance name:

Dodecyltrimethylammonium bromide

EC Number:

214-290-3

EC Name:

Dodecyltrimethylammonium bromide

Cas Number:

1119-94-4

Molecular formula:

C15H34N.Br

IUPAC Name:

dodecyltrimethylazanium bromide

Test material form:

not specified

Details on test material:

Name as cited in the study: DTAB
Purity: 99%
Supplier: Xiamen Pioneer Technology Company Limited (China)

Sampling and analysis

Analytical monitoring:

not specified

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

other: C. Pyrenoidosa and S. quadricauda

Details on test organisms:

TEST ORGANISM
- Common name: Chlorella pyrenoidosa and Scenedesmus quadricauda
- Source (laboratory, culture collection): Freshwater Algae Culture Collection of the Institute of Hydrobiology, the Chinese Acadamy of Sciences
- Method of cultivation: the green freshwater algae were grown in 500 mL erlenmeyer flasks containing 200 mL of culture medium. The cultures were incubated at 25°C and illuminated at the irrafdiance of 3000 lux for a 12 h light/12 h dark regime. The vessels were manuallly shaken three times per day. The density was kept to 5x10^5 cells/mL and 1x10^4 cells/mL for C. pyrenoidosa and S. quadricauda, respectively.

ACCLIMATION: pre-cultures were propagated for 1 to 3 days.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Test conditions

Test temperature:

25°C

pH:

8

Details on test conditions:

TEST SYSTEM
- Test vessel: 500 mL erlenmeyer flasks, fill volume: 200 mL
- Initial cells density: 5x10^5 cells/mL and 1x10^4 cells/mL for C. pyrenoidosa and S. quadricauda respectively.
- Control end cells density: not indicated
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 1 (for each concentration one control containing only algal medium was included)

GROWTH MEDIUM
- Detailed composition if non-standard medium was used: NaNO3 0.025 (g/L); K2HPO4.3H2O 0.075 (g/L); MgSO4.7H2O 0.075 (g/L); CaCl2.2H2O 0.025 (g/L); KH2PO4 0.175 (g/L); NaCl 0.025 (g/L); Na2CO3 0.02 (g/L); Na2SiO3.9H2O 0.1 (g/L); Na2EDTA 0.01 (g/L); FeCl3.6H2O 0.00081 (g/L); H3BO4 2.86 (µg/L); MnSO4 2.06 (µg/L); ZnSO4.7H2O 0.222 (µg/L); (NH4)6Mo7O2.4H2O 0.039 (µg/L); CuSO4.5H2O 0.079 (µg/L).

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: distilled water

OTHER TEST CONDITIONS
- Adjustment of pH: yes, to 8.o using hydrochloric acid and sodium hydroxide
- Photoperiod: 12 h dark/12 h light
- Light intensity: 3000 lux from a fluorescent lamp

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: optical density, as the indirect biomass of the algae, was measured with a spectrophotometer at 686 nm. The cell density was calculated using the measurements of absorbance, which were transferred to cell density with a linear regression curve:
Y=42.19X-0.157 (C. Pyrenoidosa)
Y=401.39X-29.675 (S. Quadricauda)
With Y=cell density and X=OD686

TEST CONCENTRATIONS: seven concentrations were tested; not further details were provided

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

1.5 mg/L

Nominal / measured:

not specified

Basis for effect:

biomass

Remarks on result:

other: C. Pyrenoidosa

Effect concentrations 2

Key result

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

0.55 mg/L

Nominal / measured:

not specified

Basis for effect:

biomass

Remarks on result:

other: S. Quadricauda

Reported statistics and error estimates:

The median effective inhibition concentration (EC50) and its 95% confidence intervals were calculated with the probit method using the software SPSS 13.0.

Applicant's summary and conclusion

Validity criteria fulfilled:

no

Conclusions:

The EC50 for inhibition of yield for Dodecyltrimethtlammonium bromide towards freshwater algae was 1.5 and 0.55 mg/L for C. pyrenoidosa and S. quadricauda, respectively.

Executive summary:

The acute toxicity of Dodecyltrimethylammonium bromide towards two types of freshwater algae, Chlorella pyrenoidosa and Scenedesmus quadricauda, was assessed in a study available in public literature. Seven concentrations were tested in triplicate, including a control with algal medium only for each concentration. The optical cell density was measured daily with a spectrophotometer at 686 nm. After 96 hours, the EC50 -value was calculated by linear regression. The EC50 for inhibition of yield for Dodecyltrimethtlammonium bromide towards freshwater algae was 1.5 and 0.55 mg/L for C. pyrenoidosa and S. quadricauda, respectively.