1-[2,3-dihydro-1,1,2,6-tetramethyl-3-(1-methylethyl)-1H-inden-5-yl]ethan-1-one

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:

13 December 1993 to 15 December 1993

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

The upper test concentration levels appear to exceed the aqueous solubility of the test item, which may have led to an insoluble fraction present in the exposure solutions. Two duplicate samples per test level with 10 daphnids each compared with 4 replicates of 5 daphnids each, typical of more recent studies. Report is missing additional information.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1996

Report date:

1996

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

1-[2,3-dihydro-1,1,2,6-tetramethyl-3-(1-methylethyl)-1H-inden-5-yl]ethan-1-one

EC Number:

268-799-0

EC Name:

1-[2,3-dihydro-1,1,2,6-tetramethyl-3-(1-methylethyl)-1H-inden-5-yl]ethan-1-one

Cas Number:

68140-48-7

Molecular formula:

C18H26O

IUPAC Name:

1-[1,1,2,6-tetramethyl-3-(propan-2-yl)-2,3-dihydro-1H-inden-5-yl]ethan-1-one

Test material form:

liquid

Specific details on test material used for the study:

TRASEOLIDE :
Batch / Sample Code : N47
Purity : 97% active ingredient
Date of Expiry : Not known

Sampling and analysis

Analytical monitoring:

yes

Remarks:

HPLC

Details on sampling:

Test substance concentrations were determined on Day -1, 0, 1 and 2.

Test solutions

Vehicle:

no

Details on test solutions:

Preparation of Stock and Test Solutions :
The stock solution used in this study was prepared by dispersing 0.02 g of Traseolide in 2 L of ASTM medium-hard by sonication for approximately 45 minutes to make a 10 mg/L stock solution.

Test solutions were made by adding known volumes of this stock to 2.0 L of ASTM medium-hard medium.

These test solutions were used to prepare the glassware for 3 days prior to the start of the test. A second stock was used to mprepare the test solutions for the definitive test. Test solutions were prepared 24 hours before the Daphnia were added to permit test substance equilibration.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

Daphnia magna were cultured in the laboratory. Cultures were maintained in a synthetic medium with the same chemical composition and similar pH and dissolved oxygen concentration as that used to prepare the test solutions. Culture medium consists of 800 mL ASTM medium-hard medium with the addition of an organic additive, derived from the marine microalga Ascophyllum nodosum. The cultures are fed daily with cells of the green alga Chlorella vulgaris. Cultures are re-set using 10 neonates, when they become gravid their numbers are reduced from 10 to 5 and the production of neonates results in their daily removal.

Study design

Test type:

static

Water media type:

freshwater

Remarks:

ASTM medium-hard medium

Limit test:

no

Total exposure duration:

48 h

Test conditions

Hardness:

Total Hardness betwee 165 - 184 mg/L as CaCO3

Test temperature:

Temperature range during exposure : 20.5 - 23.0 °C

pH:

pH range during exposure : 8.1 - 8.4

Dissolved oxygen:

Dissolved Oxygen range during erxposure : 7.2 - 9.0 mg/L

Nominal and measured concentrations:

The biological effects are, thus, expressed based on mean measured concentrations :

Nominal Concn (mg/L) Mean Measured Concn. (mg/L)
Control 0
0.10 0.14
0.18 0.15
0.32 0.22
0.56 0.32
1.0 0.50
1.8 0.90
3.2 1.92

Details on test conditions:

Exposure vessel : 100 mL glass crystallising dish
Duplicates : 2
No. of Neonates per Vessel : 10

Temperature : 20.5 - 23 °C
Light : Normal laboratory light intensity
Light / Dark Periods : 16 hour light / 8 hour dark

The tes solutions were prepared the day before the neonates were exposed to them. At the start of the test the Daphnids were added to the test vessels and watchglasses were placed over the test vessels to isolate the Daphnids and also to prevent them from coming into contact with the air-water interface.This avoids possible indirect effects from being caught in any surface film which might have developed. During the addition of the Daphnids, care was taken not to disturb the test medium. The exposure vessels were placed in the test area according to a random distribution.

Reference substance (positive control):

not specified

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

0.42 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% confidence limits : 0-4 - 0.5 mg/L

Effect concentrations 2

Duration:

48 h

Dose descriptor:

EC0

Effect conc.:

0.22 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 3

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

1.92 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

A clear dose-response was observed.

Nominal Concn. Mean Msd. Concn. % Daphnids Immobile % Daphnids Immobile
(mg/L) (mg/L) after 24 hours after 48 hours
Control 0.0 0 10
0.1 0.14 0 5
0.18 0.15 5 5
0.32 0.22 5 10
0.56 0.32 5 15
1.0 0.50 20 85
1.8 0.90 45 85
3.2 1.92 50 100

Applicant's summary and conclusion

Validity criteria fulfilled:

not specified

Conclusions:

EC50 (48 hour) = 0.42 mg/L (95% Confidence Limits : 0.4 - 0.5 mg/L)
EC0 (48 hour) = 0.22 mg/L
EC100 (48 hour) = 1.92 mg/L

Executive summary:

EC50 (48 hour) = 0.42 mg/L (95% Confidence Limits : 0.4 - 0.5 mg/L)

EC0 (48 hour) = 0.22 mg/L

EC100 (48 hour) = 1.92 mg/L