4-[4-trans-(3,4-Difluorophenyl)-cyclohexyl]-cyclohexanone

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

May 09, 2001 - May 11, 2001

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Reliability 1

Data source

Reference

Reference 1

Reference Type:

study report

Title:

Unnamed

Year:

2005

Report date:

2005

Reference 2

Reference Type:

study report

Title:

Unnamed

Year:

2001

Report date:

2001

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

1992

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

1992

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

4-[4-trans-(3,4-Difluorophenyl)-cyclohexyl]-cyclohexanone

EC Number:

604-593-2

Cas Number:

147622-85-3

Molecular formula:

C18 H22 F2 O

IUPAC Name:

4-[4-trans-(3,4-Difluorophenyl)-cyclohexyl]-cyclohexanone

Sampling and analysis

Analytical monitoring:

yes

Remarks:

The analysis of a saturated aqueous solution revealed that the water solubility of the test item was < 0.4 mg/L; so the actual test item concentrations could not be determined

Test solutions

Vehicle:

no

Details on test solutions:

Macro nutrients (mg/L)
CaCI2 •2H20: 293.80
MgSO4•7H20: 123.30
NaHCO3: 64.80
KCI: 5.80
Na2SiO3•9H20: 10.00
NaNO3: 0.27
KH2PO4: 0.14
K2HPO4: 0.18

Trace elements (mg/L)
B: 0.5000
Fe: 0.2000
Mn: 0.1000
Li, Rb and Sr: 0.0500
Mo: 0.0250
Br: 0.0125
Cu and Zn: 0.0063
Co and I: 0.0025
Se: 0.0010
V: 0.0003

Macro nutrients (mg/L)
Na2EDTA • 2H20: 2.50

Vitamins (μg/L):
Thiamine: 75.00
B12: 1.00
Biotin: 0.75

- pH: 7.89

Preparation of the Test Item:
The test medium (reconstituted water and test material) was freshly prepared. Therefore, the calibrated flask with test material and reconstituted water, was treated in an ultrasonic device for 1 hour. Subsequently the preparation was aerated, and stirred with a magnetic stirrer for further 23 hours. After 24 hours, the preparation was given through a nutsch filter (pore size > 10 - < 16 µm. The filtrate of the test material preparation (water accommodated fraction) was used fort he study.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

Species: Daphnia magna Straus
Culture conditions: The Daphnia magna were kept in reconstituted water in glass-vessels. The study was located in an air-conditioned room in the Institute of Toxicology. Lighting was controlled by a ti
mer to provide a 16 hours light - 8 hours dark regime.

Temperature and humidity in the experimental room was measured.

At the start of the experimental phase 5 Daphnia magna were introduced in each test vessel (25 mL, all-glass) containing 10 ml reconstituted water with or without test material. The vessels were open. The test media were freshly prepared before the introduction of the young Daphnia magna.
The Daphnia magna were not fed, and the test medium was not aerated during the test.

Feeding: The parental daphnids are fed with fresh water algae. once a week.

Age: Offspring less than 24 hours old were used for the study.
Acclimation period: same as test
Feeding during test: None

ACCLIMATION: not necessary
Acclimation conditions (same as test or not): same conditions as in test

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Test conditions

Test temperature:

21°C in all test vessels

pH:

pH at test start in all vessels: 7.78-7.93
pH at test end in all vessels: 7.52-7.70

Dissolved oxygen:

at test start in all vessels: 97.3-97.8%
at test end in all vessels: 96.8-97.5%

Nominal and measured concentrations:

nominal: 100 mg/L

Details on test conditions:

EXPOSURE:
The study was performed in an air-conditioned room. For the study glass vessels containing 10 mL either reconstituted water (control group) or test medium (test item group) were used. Each
test vessel contained five daphnids. They were not fed and the media were not aerated during the exposure.
The test was performed as a static test in open vessels.
The duration of exposure was 48 hours. During the exposure period, the mobility of the daphnids was assessed daily, i.e. after 24 and 48 hours.

- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: ELENDT M4 medium according to guideline
- Culture medium different from test medium: no
- Intervals of water quality measurement: 48 h

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 h light/8 h dark
- Light intensity: not reported

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): mobility

CONCENTRATIONS(S):
A solution of a nominal test item concentration of 100 mg/L was tested in the present study.

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 2

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

An aqueous solution of nominal 100 mg/L of the test item revealed no aquatic toxicity in the test system. The 48 hour EC50 for Daphnia magna exceeded the maximum solubility of the test material in reconstituted water (< 0.4 mg/L) and, thus, could not be determined in this test.

- Behavioural abnormalities: no
- Other biological observations: no
- Mortality of control: no
- Other adverse effects control: no
- Abnormal responses: no
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: no

Results with reference substance (positive control):

No positive control used in this study. The accuracy and reliability of the test method is demonstrated periodically as recommended by guidelines with potassium dichromate.

Any other information on results incl. tables

Study Design

The objective of this study was to determine the acute toxicity of the test material using Daphnia magna.

For this purpose, juvenile Daphnia magna were exposed to an aqueous test material solution over 48 hours, under defined conditions. The study comprised of four test vessels per concentration containing five Daphnia magna each, i.e. 20 Daphnia magna per concentration (test medium group) and control group.

Daphnia magna were exposed to a nominal test material concentration of 100 mg/L (limit test) in an open static system.

Results

After exposure of Daphnia magna o a nominal concentration of 100 mg/L for 48 hours, the following results were obtained:

 

Nominal concentration (mg/L)	Daphnia magna immobilized/exposed
	24 h	48 h
0	0/20	0/20
100	0/20	0/20

Daphnia magna exposed to an aqueous preparation (water accommodated fraction) of the nominal concentration of 100 mg/L the test item were not affected.

The test material concentration in the aqueous test medium could not be determined with standard analytical methods due to its low water solubility (< 0.4 mg/L). The development of an analytical method with a sufficiently low detection and quantification limit is complex. Due to the absence of any adverse effects at the saturation

concentration, the study was performed without analytical concentration verification.

For the test material, the following nominal EC50 values for Daphnia magna were determined:

24 h EC50 > 100 mg/L

48 h EC50 > 100 mg/L

No effect on the mobility of the daphnia was observed at a nominal concentration of 100 mg/L.

Conclusion

An aqueous solution of nominal 100 mg/L of the test item revealed no aquatic toxicity in the test system. The 48 hour EC50 for Daphnia magna exceeded the maximum solubility of the test material in reconstituted water (< 0.4 mg/L) and, thus, could not be determined in this test.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

An aqueous solution (water accommodated fraction) of nominal 100 mg/L of the test item revealed no aquatic toxicity in the test system. The 48 hour EC50 for Daphnia magna exceeded the maximum solubility of the test material in reconstituted water (< 0.4 mg/L) and, thus, could not be determined in this test.

Executive summary:

This study was performed according to GLP and the methods applied are fully compliant with OECD TG 202. An aqueous solution (water accommodated fraction) of nominal 100 mg/L of the test item revealed no aquatic toxicity in the test system. The 48 hour EC50 for Daphnia magna exceeded the maximum solubility of the test material in reconstituted water (< 0.4 mg/L) and, thus, could not be determined in this test.