Reaction products of “Fatty Acids, C16-18 and C18-unsatd., Me esters; sulfuric acid and sodium 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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Batch: 2018060002
pH: 7.60
moisture content: 30.29%

Analytical monitoring:

yes

Details on sampling:

Solutions at T=0h were analysed taken directly from the starting solutions without algae. Solutions at T=72h were taken from one abiotic replicate for each concentration level.

Vehicle:

no

Details on test solutions:

OECD algal test medium was used.

Test solutions of required concentrations were prepared by direct addition (by weighing) from the test item with the algal medium. The prepared samples were stirred 10 minutes at 20 ± 2°C, darkness. After this step, the samples were filtrated on cellulose acetate filter (porosity: 0.45 µm) after a settling period of 10 minutes.

Test organisms (species):

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

Details on test organisms:

Freshwater unicellular green alga Pseudokirchneriella subcapitata of the chlorococcal order strain number CCAP 278.4 was used in this study.
The algae cultures are stored in the laboratory on a solid medium (LC/agar Petri plates) and in a liquid medium with regular sub-culturing (every week).

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Remarks on exposure duration:

Observations at 24, 48 and 72 h

Test temperature:

22.5-23.0°C

pH:

7.8 - 8.1

Nominal and measured concentrations:

Nominal : 1.0 - 3.2 - 10 - 32 - 100 mg test item/L

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

LOEC

Effect conc.:

3.2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

39.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

3.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

4 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: yield

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

1.2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: yield

Details on results:

The results obtained for the test item “RICOIL EN” on the toxicological endpoint “inhibition of growth rate” indicate an ErC50-(0-72h) = 39.8 mg/L [28.2 – 56.2]value expressed in nominal test item concentration.

The results obtained for the test item “RICOIL EN” on the toxicological endpoint “inhibition of growth rate” indicate an ErC10-(0-72h) = 3.8 mg/L [1.8 – 7.8], value expressed in nominal test item concentration.

The results obtained for the test item “RICOIL EN” on the toxicological endpoint “Yield inhibition” indicate an EyC50-(0-72h) = 4.0 mg/L [3.0 – 4.7], value expressed in nominal test item concentration.

The results obtained for the test item “RICOIL EN” on the toxicological endpoint “Yield inhibition” indicate an EyC10-(0-72h) =1.2 mg/L [0 – 1.5], value expressed in nominal test item concentration.

Results with reference substance (positive control):

The last algal growth inhibition test performed with the reference item K2Cr2O7 (June 02, 2020 gave an ErC50(0-72h) = 0.92 mg/L (0.81 – 1.03), indicating that the algae sensitivity is correct (within the accepted interval of 0.65 to 1.73 mg/L fixed by the International Standard NF EN ISO 8692 from Mai 2012 as mentioned in the OECD 201 Guideline) and in accordance with previous data obtained by the laboratory.

Validity criteria fulfilled:

yes

Conclusions:

The results obtained for the test item “RICOIL EN” on the toxicological endpoint “inhibition of growth rate” indicate an ErC50-(0-72h) = 39.8 mg/L [28.2 – 56.2], value expressed in nominal test item concentration.

The results obtained for the test item “RICOIL EN” on the toxicological endpoint “inhibition of growth rate” indicate an ErC10-(0-72h) = 3.8 mg/L [1.8 – 7.8],value expressed in nominal test item concentration.



The results obtained for the test item “RICOIL EN” on the toxicological endpoint “Yield inhibition” indicate an EyC50-(0-72h) = 4.0 mg/L [3.0 – 4.7], value expressed in nominal test item concentration.

The results obtained for the test item “RICOIL EN” on the toxicological endpoint “Yield inhibition” indicate an EyC10-(0-72h) =1.2 mg/L [0 – 1.5],, value expressed in nominal test item concentration.

Executive summary:

The aim of this study was to determine the effects of the test item “RICOIL EN” on the growth of the unicellular green alga Pseudokirchneriella subcapitata, according to the OECD 201 guideline (March 2006, corrected July 2011).

 

Following the results of preliminary tests (non-GLP), a final test at five nominal test item concentrations was performed, in order to evaluate the significant effect on the test organism. The effects on the algal growth were determined by cell counting daily for 72 hours.

 

The concentration of “RICOIL EN” in the control and the solutions was checked by Carbon Analyzer during the study at the start (T=0h) and at the end of the test (T=72h).

 

The results of this study are summarized below:

Test item                           RICOIL EN

 

Test system                      Pseudokirchneriella subcapitata

 

Exposure duration               72 hours

 

Test concentrations             Control – 1.0 – 3.2 – 10 – 32 and 100 mg/L

 

Incubator                           Temperature 22.5 °C – 23.0°C ; shaking at 120 rpm; light intensity: 6692 Lux

 

Measurement of cell growth  Beckman Coulter Z2 and Malassez counting cell

 

Validity criteria:                   In the control, the increase of the biomass during 72 hours was determined to be higher than a factor of 16. The coefficients of variation ofdaily section-by-section specific growth rate and of average specific growth rate were determined respectively to be less than 35% and 7% in the control. The validity criteria were successfully fulfilled.

Results

 

Based on the results of Total Carbon in solutions containing the test item “RICOIL EN”, the measured concentration are well maintained within ± 20 per cent of the initial measured concentration (- 4.4% to +16.3%).

Consequently, the test item“RICOIL EN”can be considered as stable in the testing conditions after 72 hours of exposure.

                                        

NOEC	LOEC
1.0 mg/L	3.2 mg/L

 

The results obtained for the test item“RICOIL EN”on the toxicological endpoint “inhibition of growth rate” indicate anErC₅₀-(0-72h)= 39.8 mg/L [28.2 – 56.2],value expressed in nominal test item concentration.

 

The results obtained for the test item“RICOIL EN” on the toxicological endpoint “inhibition of growth rate” indicate anErC₁₀=3.8 mg/L [1.8 – 7.8],value expressed in nominal test item concentration.

 

The results obtained for the test item“RICOIL EN”on the toxicological endpoint “Yield inhibition” indicate anEyC₅₀-(0-72h)= 4.0 mg/L [3.0 – 4.7],value expressed in nominal test item concentration.

 

The results obtained for the test item“RICOIL EN”on the toxicological endpoint “Yield inhibition” indicate anEyC₁₀-(0-72h)= 1.2 mg/L [0 – 1.5],value expressed in nominal test item concentration.

 

Key value for chemical safety assessment

EC50 for freshwater algae:

39.8 mg/L

EC10 or NOEC for freshwater algae:

3.8 mg/L