Reaction products of enzymatic esterification of linolenic acid and 1,2-octanediol

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OPPTS 850.5400 (Algal Toxicity, Tiers I and II) (January 2012)

Test guideline 3

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

1-hydroxyoctan-2-yl octadeca-9,12,15-trienoate; 2-hydroxyoctyl octadeca-9,12,15-trienoate; 2-hydroxyoctyl octadeca-9,12-dienoate; octane-1,2-diol

EC Number:

944-490-2

Molecular formula:

unknown

IUPAC Name:

1-hydroxyoctan-2-yl octadeca-9,12,15-trienoate; 2-hydroxyoctyl octadeca-9,12,15-trienoate; 2-hydroxyoctyl octadeca-9,12-dienoate; octane-1,2-diol

Test material form:

liquid

Specific details on test material used for the study:

No correction for purity of the Test Item was applied because this is an UVCB Test Item.

Test organisms

Test organisms (species):

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

Test conditions

Test temperature:

Culture temperature was checked at the beginning of the experiment and each day thereafter in a flask filled with water, in the climatic chamber. In addition, water temperature was continuously measured (with a min/max thermometer) within the climate chamber. The temperature was 22.6-22.8°C measured in the flask and were in the range of 21.4 and 23.2°C measured within the climate chamber.

pH:

The pH was checked at the beginning and at the end of the test, in the control and each concentration. The pH of the control medium was not increased by more than 1.5 units during the test. The range of the pH was 7.42 – 8.83 during the experiment.

Details on test conditions:

The algal culture flasks were continuously illuminated. The light intensity at the position occupied by algal culture flasks during the test was about 7773 lux (equivalent to ~105 E/m2/s), which was ensured with fluorescent lamps (with a spectral range of 400-700 nm). The differences in light intensity between the test vessels did not exceed  15 % and therefore provided equal conditions for each test vessel. control

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

72 h

Dose descriptor:

other: ELR50

Effect conc.:

97.47 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Effect concentrations 2

Duration:

72 h

Dose descriptor:

NOELR

Effect conc.:

12.5 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Effect concentrations 3

Duration:

72 h

Dose descriptor:

LOELR

Effect conc.:

25 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Any other information on results incl. tables

In conclusion, under the conditions of this study, the calculated endpoints for the effect of the Test Item were the following:

 

Table 6: Summary of endpoints

Parameter (0-72 h)	Growth rate (r) [mg/L nominal loading rates WAF]	Yield (y) [mg/L nominal loading rates WAF]	Biomass (b) [mg/L nominal loading rates WAF]
ELR50	---	---	97.47
95 % conf. limits	---	---	76.64 – 123.95
NOELR	50	12.5	12.5
LOELR	100	25	25

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Executive summary:

The effect of Test Item was assessed on algal growth using the unicellular green alga Pseudokirchneriella subcapitata, over an exposure period of 72 hours.

Toxic response was observed during the preliminary range-finding test, therefore 5 test concentrations in a geometric serieswith a separation factor of 2.0 and 1 untreated Control were tested in the Main experiment.

The concentration of the total carbon content was analytically determined at the start and at the end of the experiment. The following nominal concentrations were tested: 6.25, 12.5, 25, 50 and 100 mg/L nominal loading rates WAFs. The biological results are based on these concentrations.

 

The test design included 3 replicates at each test concentration and 6 replicates for the untreated Controls.

Statistical comparisons of biomass, average specific growth rates and yield in control and in treated groups were carried out using analysis of variance (ANOVA) and Bonferroni t-Test (a= 0.05) by TOXSTAT software.The E_bLR₅₀value of the Test Item and its confidence limits were calculated using Probit analysisby TOXSTAT software.

In conclusion, under the conditions of this study, the calculated endpoints for the effect ofthe Test Itemwere the following:

Table 1:Summary of endpoints

Parameter (0-72 h)	Growth rate (r) [mg/L nominal loading rates WAF]	Yield (y) [mg/L nominal loading rates WAF]	Biomass (b) [mg/L nominal loading rates WAF]
ELR50	---	---	97.47
95 % conf. limits	---	---	76.64 – 123.95
NOELR	50	12.5	12.5
LOELR	100	25	25