cis-2-tert-butylcyclohexyl acetate

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:

19 May 1992 to 12 Mar 1993

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

The 0, 2.8 and 44 mg/L test concentrations were analysed directly after the start of the test and after 48 hours.

Vehicle:

no

Details on test solutions:

Substance dissolved in Elendt M4-medium by means of Ultra-turrax (60 sec. at 8000 RPM)

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISMS
- Strain: Daphnia magna Straus, parthenogenetic females
- Source: Original clones from Bundesgesundheitsamtes Berlin, further cultured at Bayer AG test laboratory
- Age at study initiation: 6-24 hours

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

15 ºdH

Test temperature:

20.7 - 21.0 ºC

pH:

7.4 - 7.9

Dissolved oxygen:

6.9 - 8.4 mg/L

Nominal and measured concentrations:

- Nominal concentrations: 0, 2.8, 3.9, 5.5, 7.8, 11, 16, 22, 31, 44 mg/L
- Measured concentrations: < 0.5, 2.1 and 47.6 mg/L for 0, 2.8 and 44 mg/L test cocnentrations, respectively.

Details on test conditions:

TEST SYSTEM
- Test vessel: 250 mL (BSB-bottles with plastic stoppers)
- Type: closed
- Aeration: no
- No. of organisms per vessel: 40
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2

TEST MEDIUM / WATER PARAMETERS
- Preparation of dilution water: Elendt M4-medium
- Culture medium different from test medium: no

EFFECT PARAMETERS MEASURED:
- mobility at 24h and 48h

Reference substance (positive control):

not specified

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

17 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% confidentiality range: 14-23 mg/L

Details on results:

- Mortality of control: none of the animals died during the exposure period
- Effect concentrations exceeding solubility of substance in test medium: yes

Reported statistics and error estimates:

The EC50 was calculated by means of probit-analysis.

Cumulative immobility data from the toxicity test with Daphnia magna

Nominal concentration (mg/L)	Immobile daphnids at 48h
	absolute	%
control	0	0
2.8	0	0
3.9	0	0
5.5	0	0
7.8	0	0
11	12	15
16	29	36
22	59	74
31	80	100
44	80	100

Validity criteria fulfilled:

yes

Conclusions:

The 48-h EC50 value is 17 mg/L in Dapnia magna.

Executive summary:

The acute toxicity of Verdox to Daphnia magna was determined in a GLP-compliant EU guideline C.2 study. In this static test using closed vessels, groups of 40 daphnids were exposed for 48 hours to nominal test concentrations of 0, 2.8, 3.9, 5.5, 7.8, 11, 16, 22, 31 and 44 mg/L of the test substance in M4 -medium. The 0, 2.8 and 44 mg/L test concentrations were analysed at the start and the end of the test. Measured concentrations were within 80% of nominal values. The EC50 was calculated to be 17 mg/L by Probit-analysis.

Description of key information

The acute toxicity of Verdox to Daphnia magna was determined in a GLP-compliant EU guideline C.2 study. In this static test using closed vessels, groups of 40 Daphnids were exposed for 48 hours to nominal test concentrations of 0, 2.8, 3.9, 5.5, 7.8, 11, 16, 22, 31 and 44 mg/L of the test substance in M4 -medium. The 0, 2.8 and 44 mg/L test concentrations were analysed at the start and the end of the test. Measured concentrations were within 80 % of nominal values. The EC50 was calculated to be 17 mg/L by Probit-analysis.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

17 mg/L