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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

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Diss Factsheets

Ecotoxicological information

Toxicity to aquatic algae and cyanobacteria

Administrative data

toxicity to aquatic algae and cyanobacteria
Type of information:
experimental study
Adequacy of study:
key study
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference Type:
study report

Materials and methods

Test guideline
according to guideline
OECD Guideline 201 (Freshwater Alga and Cyanobacteria, Growth Inhibition Test)
GLP compliance:
yes (incl. QA statement)

Test material

Constituent 1
Chemical structure
Reference substance name:
EC Number:
EC Name:
Cas Number:
Molecular formula:
Specific details on test material used for the study:
Test item: Methyl Cyclopentenolone
Common name of active ingredient (a.i): Methyl cyclopentenolone
CAS number of a.i: 80-71-7
Molecular weight of a.i.: 112.13 g.moL-1
Molecular formula of a.i.: C6H8O2
Received on: 12/Dec/2017
Bioagri Laboratórios Ltda. code: AGR-0921/17
Declared concentration of a.i. (Sponsor): >99.0% w/w
Batch number: D270001706002
Physical state: White, crystal powder
Manufacture date: 08/Jun/2017
Expiry date: 07/Jun/2018
Information source: Information provided by the sponsor

Sampling and analysis

Analytical monitoring:
not specified

Test solutions

Details on test solutions:
The primary stock solution used in the range-finding test was prepared by dissolving 0.025 g of the test substance in volume completed to 250 mL with OECD medium, resulting in a concentration of 100 mg.L-1. The stock solution of 10 mg.L-1 was prepared from dilution of the primary stock solution.
The stock solution used in the definitive test was prepared by dissolving 0.1 g of the test substance in volume completed to 1000 mL with OECD medium, resulting in a concentration of 100 mg.L-1.
From these initial stock solutions, a series of dilutions was prepared in order to obtain the desired tested concentrations

Test organisms

Test organisms (species):
Raphidocelis subcapitata (previous names: Pseudokirchneriella subcapitata, Selenastrum capricornutum)
Details on test organisms:
Test System Selection Justification:
The alga species used as test system is recommended in the Guideline OECD 201 (2011).

Origin of the Test System:
The test system was obtained from Culture Collection of Algae at Goettingen University - SAG 61.81 on October, 08th, 2013, and is recommended by the Guideline OECD 201 (2011).

Stock Culture Maintenance:
The stock culture was prepared and maintained under lab-controlled conditions in solid medium with protease peptone.
The inoculated solid medium was kept inside a culture room, with controlled temperature of 21 to 24°C and luminosity of 2100 ± 10% lux. After algae cultures reached an ideal growth (about one week), they were maintained at temperature of 2 to 6°C and luminosity of 100 to 200 lux in order to slow down the algae growth.

Study design

Test type:
Total exposure duration:
72 h

Test conditions

Test temperature:
22.0 to 22.3oC
Reference substance (positive control):

Results and discussion

Effect concentrationsopen allclose all
Key result
72 h
Dose descriptor:
other: EyC50
Effect conc.:
3.44 mg/L
Basis for effect:
other: yield
Remarks on result:
other: (95% confidence limits = 2.75 to 4.29 mg.L-1)
Key result
72 h
Dose descriptor:
other: ErC50
Effect conc.:
30.05 mg/L
Basis for effect:
growth rate
Remarks on result:
other: (95% confidence limits = 22.32 to 40.46 mg.L-1)

Applicant's summary and conclusion

Validity criteria fulfilled: