[No public or meaningful name is available]

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:

2020-12-07 to 2021-03-15

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2021

Report date:

2021

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Reaction mass of 2-(3a,4,5,6,7,7a-hexahydro-1H-4,7-methanoinden-5-yloxy)ethyl acrylate and 2-(3a,4,5,6,7,7a-hexahydro-1H-4,7-methanoinden-6-yloxy)ethyl acrylate

Molecular formula:

C15 H20 O3

IUPAC Name:

Reaction mass of 2-(3a,4,5,6,7,7a-hexahydro-1H-4,7-methanoinden-5-yloxy)ethyl acrylate and 2-(3a,4,5,6,7,7a-hexahydro-1H-4,7-methanoinden-6-yloxy)ethyl acrylate

Test material form:

liquid

Details on test material:

- Name: 2-Propenoic acid,2-[[3a,4,5,6,7,7a-hexahydro-4,7-methano-1H-inden-5(or 6)-yl]oxy]ethyl ester
- CAS No.: 68169-12-0 (outside EU)
- EC Name: Reaction mass of 2-(3a,4,5,6,7,7a-hexahydro-1H-4,7-methanoinden-5-yloxy)ethyl acrylate and 2-(3a,4,5,6,7,7ahexahydro-1H-4,7-methanoinden-6-yloxy)ethyl acrylate
- EC Number: 951-956-9
- Batch No.: OX8J0799
- Molecular Weight: 248.32 g/mol
- Physical State: liquid
- Colour: clear
- Active Components: 98.52% active components (different isomers), 1.48% 2-Cyclopenta-1,3-dienyloxyethan-1-ol
- Purity: 98.52%
- Expiry Date: 17 September 2023
- Storage Conditions: room temperature
- Safety Precautions: The routine hygienic procedures were sufficient to assure personnel health and safety.

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Separate replicates for the test item analysis after 0 hours and 72 hours were prepared in the original test vessels with algae at the start of the exposure. The replicates for test end were incubated under test conditions until analysis.

Test solutions

Vehicle:

no

Details on test solutions:

Seven water accommodated fractions (WAF) were prepared with nominal loading rates of the test item in the range of 0.0110 to 11.0 mg/L set up in a geometric series with a factor of √10. Three water accommodated fraction with a nominal loading of 11.0, 3.48 and 1.10 mg/L were prepared separately. For the loading rates, an appropriate amount of the test item was pipetted onto the surface of the dilution water in a glass bottle. For this purpose, the density was taken into account. These dispersions were shaken for at least 24 hours with 20 rpm at room temperature. After a separation phase of 1 hour, the aqueous phase or WAF was removed by siphoning (from the approximate center of the glass flask). The WAFs were checked via laser beam (Tyndall effect) for undissolved test item (formation of an emulsion). The Tyndall effect was negative. The resulting water accommodated fractions (WAF) were used in the test. Appropriate volumes of the WAF 1.10 mg/L were diluted with dilution water to achieve the other 4 loading levels for testing: 0.0110 – 0.0348 – 0.110 – 0.348 mg/L.

Test organisms

Test organisms (species):

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

Details on test organisms:

Cultivation at test facility: Fresh stocks are prepared every month on Z-Agar. Light intensity amounts 2567 – 5130 lux for 24 hours per day.
Culture medium: Nutrient medium Z according to LÜTTGE et al. (1994)

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

Test temperature:

22.5 - 23.5

pH:

8.04 - 9.10

Nominal and measured concentrations:

nominal: 11, 3.48, 1.1, 0.348, 0.11, 0.0348, 0.011 mg/L
measured: 10.1, 2.4, 0.406, 0.109, 0.0333, 0.00998, 0.00363 mg/L

Reference substance (positive control):

yes

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

72 h

Dose descriptor:

EL10

Effect conc.:

0.011 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: water accommodated fractions (WAF)

Effect concentrations 2

Key result

Duration:

72 h

Dose descriptor:

EL50

Effect conc.:

0.807 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: water accommodated fractions (WAF)

Details on results:

All effect values given are based on the nominal loading rates of the test item.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Based on the nominal loading rates, the 72 hours-EL50 was 0.807 mg/L, and the EC10 was 0.0112 mg/L.

Executive summary:

The aim of the study was the determination of the effects on growth rate and yield over a period of 72 hours.

The study was conducted under static conditions with an initial cell density of 6352 cells/mL. Seven water accommodated fractions (WAF) were prepared with nominal loading rates of the test item in the range of 0.0110 to 11.0 mg/L set up in a geometric series with a factor of √10. Three water accommodated fraction with a nominal loading of 11.0, 3.48 and 1.10 mg/L were prepared separately. Appropriate volumes of the WAF 1.10 mg/L were diluted with dilution water to achieve the other 4 loading levels for testing: 0.0110 – 0.0348 - 0.110 – 0.348 mg/L.
Three replicates were tested for each test item loading and six replicates for the control. The environmental conditions were within the acceptable limits.

All loading rates of the test item and the control were analytically determined in fresh media (0 hours) and at the end of the exposure interval (72 hours) via GC-MS. At the start of the exposure the measured concentrations were in the range of 0.00555 to 10.7 mg/L. At the end of exposure after 72 hours, the measured concentrations were in the range of 54 to 95% of the initially measured concentrations of the test item.

Based on the nominal loading rates, the 72 hours-EL50 was 0.807 mg/L, and the EC10 was 0.0112 mg/L.