Reaction mass of L-valine and ethanesulphonic acid and octadecan-1-ol and docosan-1-ol and eicosan-1-ol

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:

7/6/18 - 27/7/18

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Reaction mass of L-valine and ethanesulphonic acid and octadecan-1-ol and docosan-1-ol and eicosan-1-ol

Cas Number:

2125692-22-8

Molecular formula:

C25-31H54-66NO5S

IUPAC Name:

Reaction mass of L-valine and ethanesulphonic acid and octadecan-1-ol and docosan-1-ol and eicosan-1-ol

Test material form:

solid

Test solutions

Vehicle:

yes

Details on test solutions:

The stock solution was prepared as water saturated solution by adding 89.9 mg test item (including a factor of 1.11 to take into account the dilution caused by addition of the algal inoculum) to 1000 mL test medium and shaking for 23.8 h using an overhead shaker at 23.0 – 23.7 °C. The water saturated solution was filtered through a fibre glass filter with a retaining range till 0.6 μm. The filter was prepared by rinsing with purified water and preconditioning with ca. 50 mL stock solution (which was discarded) to reduce adsorption of the test item. This filtered stock solution was used as highest test item loading rate in the test.
Nominal test item loading rate [mg/L] 0 1 3 9 27 81

Test organisms

Test organisms (species):

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

Details on test organisms:

The test organism Raphidocelis subcapitata (Strain No. 61.81 SAG) originates from the Culture Collection of Algae at the University of Goettingen. The strain used for this study has been cultured in suspension culture at Hydrotox GmbH since July 2017. Twice a week, the stock suspension is inoculated into fresh Holm-Hansen medium (composition: 496 mg/L NaNO3, 39 mg/L K2HPO4, 75 mg/L MgSO4×7H2O, 36 mg/L CaCl2×2H2O, 58 mg/L Na2CO3, 10 mg/L Na2EDTA×2H2O, 3 mg/L citric acid, 3 mg/L iron citrate, 0.1144 mg/L H3BO3, 0.0724 mg/L MnCl2× 4H2O, 0.0088 mg/L ZnSO4×7H2O, 0.0032 mg/L CuSO4×5H2O, 0.0010 mg/L Na2MoO4×2H2O, 0.0016 mg/L CoCl2×6H2O) under axenic conditions to keep it in exponential growth. Quality assurance takes place at regular intervals by testing the sensitivity of the test organisms to the reference item potassium dichromate (Sigma, Steinheim, Germany, Lot no.: MKBF2111V). The recent quality testing was performed in December 2017 which resulted in an ErC50 (72 h) of 1.18 mg/L (CL 95 %: 0.97 - 1.42 mg/L; interlaboratory test result for ErC50: mean of 1.19 mg/L with SD of 0.27 mg/L) and an EyC50 (72 h) of 0.61 mg/L (CL 95 %: 0.42 – 0.91 mg/L).

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

Test temperature:

21 – 24 °C, constant within ± 2 °C

Details on test conditions:

The test vessels were sealed with cellulose stoppers and kept in the light incubator (specified temperature: 21 – 24 °C, constant within ± 2 °C). They were placed on the shaking table with adhesive mats and continuously shaken with 100 rpm and an orbital diameter of 5 cm. The test vessels were continuously illuminated by LEDs (warm white) with a light intensity of 88.5 μE m-² s-1 ± 8.0 %. The pH was measured at the start (0 h) and at the end (72 h) of the test. The temperature was measured continuously.

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

2.78 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 2

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

2.35 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 3

Duration:

72 h

Dose descriptor:

LOEC

Effect conc.:

1.11 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 4

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

0.55 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Details on results:

The test is valid according to OECD Test Guideline 201 (23 March 2006).
The measured TOC concentrations in the test item treatments were 8.17 – 56.10 % of the nominal TOC concentrations.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

EC50 (72h) = 2.78 mg/L

Executive summary:

As the measured test item concentrations are not within ± 20 % of the nominal loading rates,

according to OECD 201 (2006), all results are given in relation to the analytically measured test

item concentrations (geometric mean concentrations).

(Lowest/No Observed) Effect Concentration Measured test item concentration [mg/L] and Growth rate (72 h)

EC50 2.78

EC10 2.35

LOEC 1.11

NOEC 0.55

The test is valid according to OECD Test Guideline 201 (23 March 2006).

The measured TOC concentrations in the test item treatments were 8.17 – 56.10 % of the nominal TOC concentrations.