Reaction mass of dodecyl acrylate and tridecyl acrylate

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1989-10-02 to 1989-10-06

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Meets National Standard Methods (DIN) with acceptable restrictions Read across was performed with Laurylacrylat 12/14 (mixture of laurylacrylate (CAS No.: 2156-97-0) and tetradecylacrylate (CAS No.: 21643-42-5) . Please refer to IUCLID section 13 for read across justification. The use of Tween 80 as solubilizer could have lead to generation of artifacts and thus generated lower effect concentrations.

Qualifier:

according to guideline

Guideline:

other: German national standard DIN 38412, Part 9.

Deviations:

no

GLP compliance:

no

Analytical monitoring:

no

Details on test solutions:

The stock solution was prepared by dissolving 1000 mg test substance and 100 mg of the solubilizer Cremophor in dilution water. The test concentrations were then prepared by dilution with test water. The test concentrations were chosen based on a range finding test.

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

- Test species: Scenedesmus subspicatus
- Strain: CHODAT
- Source: Algae collection Goettingen, SAG 86.81

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test temperature:

21.0 °C

pH:

7.18 -7.98

Nominal and measured concentrations:

- Nominal concentration: Solubilizer: Cremophor (0.10, 0.25, 0.50, 1.0, 2.5, 5.0 mg/L); Test substance: 0, 1.00, 2.50, 5.00, 10.00, 25.00, and 50.00 mg/L.
- Stock solution: 1000 mg/L
- No concentrations were measured.

Details on test conditions:

- Aeration: none
- No. of replicates: 4
- Controls: negative control, vehicle control
- Test medium: according to DIN 38412 L9
- pH during test: 7.18 - 7.98
- Temperature during test: 23.0+/-2 °C
- In vivo chlorophyll-a-fluorescence (pulsed excitation with light flashes having a wavelength of 435 nm).
- Reference substance: Potassium chromate p.a. (Merck)
- Sampling: At 0, 24, 48, 72, and 96 hours after test start, the algae cell density was determined by spectro-fluorometrical measurement using an impulse fluorometer.
- Other: The parameters pH, and temperature were determined at the end of the test. Also, at the end of the incubation period the algae cells were analyzed for signs of photosynthesis blockage by means of a spectrophotometrical scan at 300 - 780 nm. In vivo chlorophyll-a-fluorescence (pulsed excitation with light flashes having a wavelength of 435 nm).

Reference substance (positive control):

yes

Remarks:

Potassium chromate

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

51.6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 5.00 - 122.8

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

24.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 4.72 - 564.6

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

21.3 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: 6.58 - 68.64

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

51.6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: 7.93 - 204.8

Details on results:

The EC50 and EC10-values (growth rate) were 51.6 mg/L and 24.8 mg/L. The EC50 and EC10-values (biomass) were 51.6 mg/L and 21.3 mg/L.

Reported statistics and error estimates:

Statistics were performed according to Tallarida RJ and Jacob LS (1979). The dose-response relation in pharmacology, 98 -103, Springer

Effect on biomass after 72 hours:
---------------------------------
EC10 = 21.3 mg/L (P95 %: 6.58 - 68.64)
EC50 = 40.3 mg/L (P95 %: 7.93 - 204.8)


Effect on growth rate after 72 hours:
-------------------------------------
EC10 = 24.8 mg/L (P95 %: 5.00 - 122.8)
EC50 = 51.6 mg/L (P95 %: 4.72 - 564.6)

Reference 2

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

other information

Reason / purpose for cross-reference:

read-across source

Description of key information

No aquatic algae and cyanobacteria toxicity study is available on the registered substance (Reaction mass of C12-C13 acrylates, EC Number 911-296-4). However, experimental data are available on an analogue substance (Reaction mass of C12-C14 acrylates, CAS 84238-60-8).

In an experimental study conducted according to the DIN 38 412, Part 9, the EC50 (growth rate inhibition) was determined to be equal to 51.6 mg/L and the EC10 (growth rate inhibition) was equal to 24.8 mg/L.

Key value for chemical safety assessment

EC50 for freshwater algae:

51.6 mg/L

EC10 or NOEC for freshwater algae:

24.8 mg/L