2-butyryl-3-hydroxy-5-thiocyclohexan-3-yl-cyclohex-2-en-1-one

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study with analytical monitoring

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1996

Report date:

1996

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

425-150-8

EC Name:

-

Cas Number:

94723-86-1

Molecular formula:

C15 H22 O3 S

IUPAC Name:

2-butanoyl-3-hydroxy-5-(thian-3-yl)cyclohex-2-en-1-one

Details on test material:

- Name of test material (as cited in study report): 625-Triketone
- Physical state: solid
- Analytical purity: 99.5%
- Impurities (identity and concentrations): Diketone, NaCl, water
- Batch No.: LJ 27 881/1

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- The concentration control analytics have been carried out with the tested solutions of the following nominal concentrations: 125 mg/L (stock solution), 100 mg/L, 12.5 mg/L, 1.56 mg/L and control
- At the start of the test (after 0 h) the uninoculated replicates were analyzed, at the end of the test (after 72 h) both the uninoculated and inoculated replicates were analysed

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: The test was performed with an aqueous extract (eluate) of the test substance. A defined amount of the substance was weighed out and suspended by stirring it for 20 h in OECD-Medium at pH 8.5 (about. 22 °C). To remove the undissolved test substance the resulting suspension was passed through a membrane filter with a pore diameter of 0,20 µm. In the test the filtrate was used.
The nominal concentration of the filtered stock solution was 125 mg/L.

Test organisms

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Common name: green alga
- Strain: SAG 86.81
- Source (laboratory, culture collection): obtained at regular intervals from SAG (Collection of algal cultures in Göttingen) and kept in liquid culture in the "Labor für Ökotoxikologie" at BASF AG Ludwigshafen, Germany

Stern culture
Vessel: Erlenmeyer flask, nominal volume 250 ml
Volume: 100 ml
Inoculation density: 10000 cells/ml
lncubation time: weekly passage
Temperature: 23 °C ± 2 °C

Pre culture
Vessel: Erlenmeyer flask, nominal volume 250 ml
Volume: 100 ml
Inoculation density: 10000 cells/ml
lncubation time: 72 h
Temperature: 23 °C ± 2 °C

Test culture
Vessel: Erlenmeyer flask, nominal volume 250 ml
Volume: 100 ml
Inoculation density: 10000 cells/ml
lncubation time: 72 h
Temperature: 23 °C ± 2 °C

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

Test temperature:

23 ± 2 °C

pH:

uninoculated: 7.5 - 8.3
inoculated: 8.0 - 9.6

Nominal and measured concentrations:

Nominal test concentrations: control, 0.39, 0.78, 1.56, 3.13, 6.25, 12.50, 25.00, 50.00, 100.00 mg/L
Recovery rates (0 h, uninoculated): 96.2 - 102.9%
Recovery rates (72 h, uninoculated): 100.0 - 103.2%
Recovery rates (72 h, inoculated): 90.1 - 92.56%

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Material, size, headspace, fill volume: Erlenmeyer flasks plugged with gas permeable siliconesponge caps, nominal volume 250 ml, 100 ml
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 3

GROWTH MEDIUM
- Standard medium used: yes

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: ultrapure. deionized water (conductivity < 0.05 µS/cm)
- Culture medium different from test medium: no
- Intervals of water quality measurement: pH after 0 and 72 h in an uninoculated replicate per concentration and after 72 h in an inoculated replicate per concentration

OTHER TEST CONDITIONS
- Photoperiod: permanent illumination
- Light intensity and quality: artificial light

EFFECT PARAMETERS MEASURED
- Determination of cell concentrations: after 72 h in a counting chamber (Neubauer improved) in replicate 1 of the inoculated control
- Chlorophyll measurement: after 0, 24, 48, 72 h in an EOS Filterfluorometer FL 2

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

23.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 2

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

66.9 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 3

Duration:

72 h

Dose descriptor:

EC90

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 4

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

6.25 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Effect concentrations 5

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

13.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Effect concentrations 6

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

31.2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Effect concentrations 7

Duration:

72 h

Dose descriptor:

EC90

Effect conc.:

82.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass