4'-trans-Butyl-[1,1'-bicyclohexyl]-4-on

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

20.03.-01.06.1992

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

1984

Deviations:

no

Principles of method if other than guideline:

none

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Vehicle:

yes

Remarks:

Acetone

Details on test solutions:

Acetone as used as solubilizer in concentrations up to 100 μL/L. Drinking water was filtered through a layer of active coal and treated with a copper ion changer (Cu ions < 5 μg/L).
The test solution contained 5 animals.

Concentrations of the test items were (mg/L): 0.1, 0.18, 0.32, 0.58, 1.0

Test organisms (species):

Daphnia magna

Details on test organisms:

Species: Daphnia magna Straus
Source: Professor Dr. Knie
Landesamt für Wasser und Abfall,
Auf der Draap 25, 40221 Düsseldorf
Age: not older than 24 hours
decendents: Natec
20+-1°C
no ventilation
light exposure 16 h, darkness 8 h
feeding with algae Scenedesmus subspicatus

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

70 mg CaCO3/L

Test temperature:

21.5 °C

pH:

7.5

Dissolved oxygen:

96%

Nominal and measured concentrations:

nominal concentrations 0.1; 0.18; 0.32; 0.58; 1.0 mg/L; measured concentrations below the detection limits of 0.1 mg/L.

Details on test conditions:

Preparation
The test medium (fresh water and test material) was freshly prepared. Therefore, the test material was solved in the solubilizer and fresh water.

Administration
At the start of the experimental phase, 5 Daphnia magna were placed into 100 ml of reconstituted water (4 vessels/control group) or test medium (4 vessels/ test material group) or solubilizer (4 vessels/solubilizer). The Daphnia magna were not fed, and the control medium and test medium were not aerated during the test.The test vessels were labeled to assure unique identification.

Dose levels
0.1; 0.18; 0.32; 0.58; 1.0 mg/L

Observation schedule
The mobility was determined by visual control and recorded after 24 and 48 hours.

pH and oxygen concentration
The pH-values and dissolved oxygen concentration (O2) were measured in the control and all test material concentrations at the beginning and at the end of the experimental part. The pH was determined to be 7.5.

Temperature
During the experimental part, the temperature was registered in a control vessel with an electronic thermometer containing a maximum and minimum memory display. The temperature was maintained at 21.5°C.

Reference substance (positive control):

no

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

0.3 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

< 0.1 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 0.1 mg/L = limit of detection

Details on results:

The nominal EC50 (48h) was determined to be 0.30 mg/L. All test solutions were analytically determined. All measurements were below the limit of detection of 0.1 mg/L due to the very low water solubility of the test item.

The percentage of immobilized animals was calculated for each concentration. The dates were transferred in to probits and plotted logarithmic against the test concentration. The probit for 0% was set to 3.04 and the probit for 100% was set to 6.96%.

Table: calculation of the immobilisation effect in probits

%	probit	%	probit	%	probit
2,5	3,04	40	4,75	80	5,84
5	3,36	45	4,87	85	6,03
10	3,72	50	5,00	90	6,28
15	3,97	55	5,12	95	6,64
20	4,16	60	5,25	97,5	6,96
25	4,32	65	5,38
30	4,47	70	5,52
35	4,61	75	5,67

Immobilisation is shown in the following table. The control did not show any immobilisation.

Table: results of the acute immobilisation test

	immobilized daphnids
mg/L	24 h	48 h
0	0 (0)	0 (0)
100 μL acetone	0 (0)	0 (0)
0.1	0 (0)	0 (0)
0.18	0 (0)	0 (0)
0.32	6 (30)	15 (75)
0.58	10 (50)	20 (100)
1.0	20 (100)	20 (100)

Table: Immobilizing effects of the test item

	24 h [mg/L]	48 h [mg/L]
NOEC	0.18	0.18
0% immobilization	0.18	0.18
EC-50	0.45	0.30
100% immobilization	1.0	0.58

The table shows the nominal concentrations of the test item. The solutions were analyzed and no test item was found, due to the low solubility. Therefore, the EC50 (48 h) was determined to be 1.0E-5 g/L.

Validity criteria fulfilled:

yes

Conclusions:

Under the given experimental conditions, the 48 hours EC50 was determined to be below the limit of detection 0.1 mg/L due to the very low water solubility.

Executive summary:

A study was conducted according to OECD Guideline 202 from April, 4th 1984 in accordance with good laboratory practice. 20 Daphnias (Strauss) were exposed to the test item in different concentrations. Control experiments were run witth water without andy further additives and with acetone as solubilizer. After 24 and 48 h the immobilized animals were determined. Analysis shown that the test item was present in the test solution below the detection limit, thus the EC50 was determined as 1.0E-5 g/L due to the very low water solubility.

Description of key information

Under the given experimental conditions, the 48 hours EC50 was determined to be below the limit of detection 0.1 mg/L due to the very low water solubility.

Additional information

A study was conducted according to OECD Guideline 202 from April, 4th 1984 in accordance with good laboratory practice. 20 Daphnias (Strauss) were exposed to the test item in different concentrations. Control experiments were run witth water without andy further additives and with acetone as solubilizer. After 24 and 48 h the immobilized animals were determined. Analysis shown that the test item was present in the test solution below the detection limit, thus the EC50 was determined as 0.1 mg/L due to the very low water solubility.