Fatty acids, coco derivs., reaction products with glycine, potassium salts

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

03.12.2012 to 06.12.2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Auf dem Aberg 1, D-57392 Schmallenberg, Germany

Test material

Test material information

Constituent 1

Reference substance name:

dipotassium 2-dodecanamidoacetate 2-tetradecanamidoacetate

EC Number:

620-582-5

Cas Number:

301341-58-2

Molecular formula:

R-CO-NH-CH2-COOK (Note: "R-CO-" is a fatty acid residue)

IUPAC Name:

dipotassium 2-dodecanamidoacetate 2-tetradecanamidoacetate

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: Ajinomoto Co., Inc., 15-1 Kyobashi 1-Chome, Chuo-Ku, Tokyo 104-8315 Japan/Lot/Batch No.: 110825
- Expiration date of the lot/batch: 25.08.2014
- Purity test date: 24.01.2012

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: dark and cool place, protected from light

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: no
- Preliminary purification step (if any): no
- Final dilution of a dissolved solid, for the definitive test stock liquid or gel: The final test concentrations were obtained by dilution of the stock solution
- Final preparation of a solid: For the definitive test a stock solution was prepared by weighing 200 mg of the test item and dissolving in 2 L of dilution water.

FORM AS APPLIED IN THE TEST (if different from that of starting material): aqueous solution

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Details on test solutions:

The highest test concentration was prepared by solving of 50 mg test item in 1L growth medium.The further test concentrations were obtained by dilution.

Test organisms

Test organisms (species):

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

Details on test organisms:

TEST ORGANISM
- Common name: Pseudokirchneriella subcapitata
- Strain: 61.81 SAG
- Source (laboratory, culture collection): SAG, Culture Collection of Algae at Pflanzenphysiologisches Institut of the University at Göttingen, Albrecht von Haller Institut, Göttingen, Germany
- Age of inoculum (at test initiation): exponentially-growing cultures (not further specified)
- Method of cultivation: The stock cultures were maintained fulfilling the criteria of the OECD guideline. Prior to testing a pre-culture was established in standard OECD growth medium to obtain exponentially-growing algae for the test.

ACCLIMATION
- Acclimation period: not necessary
- Culturing media and conditions (same as test or not): yes (same conditions)
- Any deformed or abnormal cells observed: no

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

Test temperature:

21.5 - 22.0 °C

pH:

Control: 8.31 at test start, 8.17 – 8.63 at test end
Test cultures: initial pH 7.84 - 8.35, at test end 7.95 – 8.61

Nominal and measured concentrations:

50.0, 25.0, 12.5, 6.25 and 3.13 mg/L (nominal concentrations)

Details on test conditions:

TEST SYSTEM
- Test vessel: conical glass flasks
- Type (delete if not applicable): test vessels covered with air-permeable siliconesponge caps
- Material, size, headspace, fill volume: glass/250 mL/150 mL/100 mL
- Aeration: not reported
- Type of flow-through (e.g. peristaltic or proportional diluter): test conducted under static conditions
- Initial cells density: 10 000 cells/mL
- Control end cells density: 1784000 cells/mL
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 8
- No. of vessels per vehicle control (replicates): no vehicle used

GROWTH MEDIUM
- Standard medium used: yes (according to guideline)

TEST MEDIUM / WATER PARAMETERS
- Culture medium different from test medium: no
- Intervals of water quality measurement: pH measured in one test vessel per test concentration including the control. At the end of the test, the pH values were measured directly in test vessels. The test culture temperature was measured in one test vessel only at test start

OTHER TEST CONDITIONS
- Sterile test conditions: yes
- Adjustment of pH: no
- Photoperiod: continuous illimination
- Light intensity and quality: 8127 - 8221 lux corresponding to 60-120 E/m² x s²

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Cell concentrations were determined with an electronic particle counter at test start and after 24, 48 and 72 h

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2
- Range finding study: performed
- Test concentrations: 1.0, 10.0, and 100 mg/L
- Results used to determine the conditions for the definitive study: yes

Reference substance (positive control):

yes

Remarks:

3,5-dichlorophenol

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

3.13 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: growth rate and yield

Effect concentrations 2

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

15.4 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% CI 14.0 - 17.0 mg/L

Effect concentrations 3

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

6.32 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: yield

Remarks on result:

other: 95% CI 5.87 - 6.79 mg/L

Effect concentrations 4

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

4.45 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% CI 3.50 - 5.35 mg/L

Effect concentrations 5

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

2.98 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: yield

Remarks on result:

other: 95% CI 2.49 - 3.40 mg/L

Results with reference substance (positive control):

ErC50=2.91 mg/L (95% CI 2.35 - 3.63 mg/L). This value is in good agreement with the results of an international ring test: ErC50=3.38 +/- 1.3 mg/L

Reported statistics and error estimates:

EC50, EC20 and EC10: Probit-analysis assuming log-normal distribution
NOEC and LOEC: ANOVA followed by Williams Multiple Sequential t-test
Computer program ToxRat used for the statistical evaluations

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

In a guideline study the toxicity of acylglycinate GCK-11 -T to the unicellular, green alga Pseudokirchneriella subcapitata was determined based on cell density measurements. After 72 h exposure, NOEC values of 3.13 mg/L nominal were determined for yield and inhibition of growth rate. The 72 h EC50 for growth rate and yield were determined to be 15.41 and 6.3 mg/L nominal, respectively.

Executive summary:

The toxicity of acylglycinate GCK-11 -T to the unicellular, green alga Pseudokirchneriella subcapitata was investigated in a study conducted according to OECD Guideline 201 (Alga, Growth Inhibition Test; 2011). In this static test, exponentially-growing cultures of the alga were exposed to nominal test item concentrations of 0 (control), 3.13, 6.25, 12.5, 25.0, and 50.0 mg/L for 72 h.The cell density in each test culture was measured every 24 hours. The inhibition of growth in relation to the control cultures was determined for every exposure period. After 72 h exposure, NOEC values of 3.13 mg/L nominal were determined for yield and inhibition of growth rate. The 72 h EC50 for growth rate and yield were determined to be 15.41 and 6.3 mg/L nominal, respectively.

The study is regarded as reliable without restriction and fulfills the requirements of the guideline.

Results Synopsis

Test organism: Pseudokirchneriella subcapitata

Test type: static

growth rate

72 h NOEC=3.13 mg/L

72 h EC50=15.41 mg/L

yield

72 h NOEC=3.13 mg/L

72 h EC50=6.3 mg/L (nominal each)

Endpoint(s) effected: growth rate, yield