[2-[(2-methyl-1-oxoallyl)oxy]ethyl] hydrogen succinate

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:

2016/01/14 - 2016/03/07

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was performed following a standardised and suitable test guideline. The study was performed under GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2016

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

[2-[(2-methyl-1-oxoallyl)oxy]ethyl] hydrogen succinate

EC Number:

244-096-4

EC Name:

[2-[(2-methyl-1-oxoallyl)oxy]ethyl] hydrogen succinate

Cas Number:

20882-04-6

Molecular formula:

C10H14O6

IUPAC Name:

4-{2-[(2-methylprop-2-enoyl)oxy]ethoxy}-4-oxobutanoic acid

Constituent 2

Reference substance name:

[SPEC][/SPEC][SYN][/SYN]

IUPAC Name:

[SPEC][/SPEC][SYN][/SYN]

Constituent 3

Reference substance name:

[CS]000000111817[/CS]

IUPAC Name:

[CS]000000111817[/CS]

Test material form:

other: liquid

Details on test material:

Company internal substance number SAT 150073, Batch 4006/31
Colorless liquid at room temperature

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Duplicate samples from the freshly prepared test media (containing algae) of all test concentrations and from the controls were taken at the start of the test.
For the determination of the stability of the test item under the test conditions and of the maintenance of the test item concentrations during the test period, duplicate samples from the test media of all test concentrations and the controls (containing algae) were taken at the end of the test (after the 72 hours test period) by pouring together the contents of the test beakers of each treatment.
The samples were diluted by a factor of two with acetonitrile.
Additional samples of the control blank and the dilution solvent were taken at test start and test end without any sample treatment.
The concentrations of the test item SAT 150073, [2-[(2-methyl-1-oxoallyl)oxy]ethyl] hydrogen succinate were analysed in the duplicate test media samples from all test concentrations, and in the duplicate control samples, from both sampling times (0 and 72 hours).

Test solutions

Vehicle:

no

Details on test solutions:

The test medium of the highest test concentration of nominal 315.5 mg test item/L was prepared by dissolving 319.5 mg test item into 1012.7 mL test water by intense stirring for 15 minutes. The pH of the stock solution was adjusted with 2 mol NaOH from 4.7 to 8.2. Adequate volumes of this test medium were diluted with test water to prepare the test media of the other desired test concentrations. The test media were prepared just before introduction of the algae (= start of the test).

Test organisms

Test organisms (species):

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

Details on test organisms:

Pseudokirchneriella subcapitata (KORSHIKOV), Strain No. 61.81 SAG, formerly known as Selenastrum capricornutum, and recently renamed as Raphidocelis subcapitata (KORSHIKOV)
The algae were supplied by the „Sammlung von Algenkulturen, Albrecht-von-Haller-Institut für Pflanzenwissenschaften, Universität Göttingen", 37073 Göttingen, Germany.
The algae were cultivated in the laboratories of ibacon under standardised conditions according to the test guidelines.
For the evaluation of the quality of the algae and the experimental conditions the reference item potassium dichromate is tested at least twice a year to demonstrate satisfactory test conditions.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

Hardness:

Calculated water hardness of the test water: 0.24 mmol/L (= 24 mg/L) as CaCO3.

Test temperature:

22 - 23 °C

pH:

The pH was measured in all test item concentrations and the control at the start and the end of the test.
pH was: 8.1 to 8.2 at test start and 8.0 to 10.0 at test end

Nominal and measured concentrations:

Mean Recovery in the Test Samples
Freshly prepared: 102% (n=10, RSD 1%)
Aged Test Media: 68% (n=10, RSD 32%)

Summary of Analytical Results
Sample Description % of nominal1 Geometric Mean Value2
fresh (0h) aged (72h)
[mg test item/L] [%] [%] [%] [mg test item/L]
Control n.a. n.a. n.a. n.a.
3.17 101 65 81 2.57
10 102 48 70 7.03
31.6 103 43 67 21.1
99.9 101 85 92 92.4
315.5 101 96 99 312
1 mean value of all measured samples per treatment group
2 geometric mean values calculated using mean values of fresh and aged test media per treatment group
RSD: relative standard deviation per treatment group n: number of analysed samples
n.a.: not applicable

Details on test conditions:

Water Temperature:
The temperature was measured daily in an Erlenmeyer flask filled with water and incubated under the same conditions as the test flasks.
Water temperature was: 22-23°C

pH-Values:
The pH was measured in all test item concentrations and the control at the start and the end of the test.
pH was: 8.1 to 8.2 at test start and 8.0 to 10.0 at test end (see Table 10)
The pH in the control increased by more than 1.5 units in the control medium. However, this does not invalidate the tests since the validity criteria were met.

Light Regime:
Continuous illumination

Light Intensity:
The light intensity was measured once during the test at 6 positions distributed over the experimental area at the surface of the test media.
Mean light intensity: 5367 lux (range: 4900 to 5850 lux)

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

>= 197 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: 179 -216 mg/L

Effect concentrations 2

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 312 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:

EC20

Effect conc.:

>= 79.5 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: 68 - 92.7 mg/L

Effect concentrations 4

Duration:

72 h

Dose descriptor:

EC20

Effect conc.:

> 312 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 263 - >312

Effect concentrations 5

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

>= 49.5 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: 39.9 - 61.1 mg/L

Effect concentrations 6

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

>= 161 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 125 - 207 mg/L

Effect concentrations 7

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

>= 21.1 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

biomass

Effect concentrations 8

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

>= 21.1 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 9

Duration:

72 h

Dose descriptor:

LOEC

Effect conc.:

>= 92.4 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

biomass

Effect concentrations 10

Duration:

72 h

Dose descriptor:

LOEC

Effect conc.:

>= 92.4 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The influence of SAT 150073, [2-[(2-methyl-1-oxoallyl)oxy]ethyl] hydrogen succinate on the growth of the freshwater green algae Pseudokirchneriella subcapitata was assessed in a static dose-response test. The 72-hour EyC50 was calculated to be 197 mg test item/L (geometric mean measured) and the 72-hour ErC50 value was assessed to be >312 mg test item/L (geometric mean measured). The 72-hour NOEyC was determined to be 21.1 mg test item/L (geometric mean measured) and the associated 72-hour LOEyC was 92.4 mg test item/L (geometric mean measured). The 72-hour NOErC was determined to be 21.1 mg test item/L (geometric mean measured) and the associated 72-hour LOErC was 92.4 mg test item/L (geometric mean measured).

Executive summary:

The influence of SAT 150073, [2-[(2-methyl-1-oxoallyl)oxy]ethyl] hydrogen succinate on the growth of the freshwater green algae Pseudokirchneriella subcapitata was assessed in a static dose-response test. The 72-hour EyC50 was calculated to be 197 mg test item/L (geometric mean measured) and the 72-hour ErC50 value was assessed to be >312 mg test item/L (geometric mean measured). The 72-hour NOEyC was determined to be 21.1 mg test item/L (geometric mean measured) and the associated 72-hour LOEyC was 92.4 mg test item/L (geometric mean measured). The 72-hour NOErC was determined to be 21.1 mg test item/L (geometric mean measured) and the associated 72-hour LOErC was 92.4 mg test item/L (geometric mean measured).