2-Oxetanone, 3-C14-16-alkyl 4-C15-17-alkylidene derivs.

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:

4 - 6 July 1989

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Guideline study, non GLP. Water solubility data indicate low solubility. Data are lacking wrt stability and vapour pressure. No actual concentrations were determined. Substance identity and composition data are insufficient. No positive control to confirm sensitivity of test/batch of daphnids. Due to the fact the substance was tested at maximum water solubility and no mortalities occurred, it is justified to conclude the substance will not affect daphnids.

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

GLP compliance:

not specified

Remarks:

no quality control indication

Specific details on test material used for the study:

Substance: Basoplast 20 konz
Chargenumber: 212/89
Chemical name: stearyldiketen
Molecular formula: C36O2H69
Purity: 98.5%
Supplier: Basf Sokalan-Fab. Nord ESP/TN F 520
Water solubility: < 500 mg/L at 20 C

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

The concentration in the stock solution was 500 mg/L, this stock was stirred for 17 hours at 20 C.
Dilutions of this stock were prepared with dilution water.
From every diluted stock solution, 10 mL was taken for the preparation of the test solutions.
Test solutions were prepared with artificial freshwater.
This water was prepared by using deionized water (conductivity < 0.05 uS/cm) to which minerals (elements and macronutrients) were added as indicated in the report.
Molar ratio Ca:Mg = 4 : 1
Molar ratio Na: K = 10 : 1
Conductivity: 600-700 uSiemens/cm
pH: 8.0 +/- 0.5

Test water was aerated with oil-free air to saturation after which it was left for stabilisation

Test organisms (species):

Daphnia magna

Details on test organisms:

Origin: Testculture was originally (1978) obtained from the Institut National de Recherche Chimique Apliquee, France, but since then maintained in the Basf laboratory of Umweltanalytik und Okologie, Ludwigshafen, Germany.
Animals were 2-24 hours old when used for the test.

Culture conditions:
Hardness: 2.70 +/- 0.5 mmol/L
Ks to pH 4.3: 0.90+/- 0.1 mmol/L
Oxygen conc: > 2 mg/L
Temp: 19-21 C

Feeding: daily fed green algae culture
Light-Darkness: 16 : 8h
Lightintensity: 5 micro-einstein/mxmxs at wavelengths 400-750 nm

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

None

Hardness:

2.76 +/- 0.5 mmol/L

Test temperature:

19-21 C

pH:

8.0-8.1

Dissolved oxygen:

8.4-9.1 mg/L

Nominal and measured concentrations:

Nominal conc: 62.5 - 125 - 250 - 500 mg/L

Details on test conditions:

Test volume: 10 mL, which is 2 ml per animal
5 animals times 4 replicates per concentration level.
Observations were made at 0, 3, 6, 24 and 48 h
No data as to whether feeding was continued during the test.

Reference substance (positive control):

not specified

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 500 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: at maximum water solubility the substance does not cause effects under the conditions of the test

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

>= 500 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks on result:

other: at maximum water solubility the substance does not cause effects under the conditions of the tes

Details on results:

No mortalities observed at any time point.
Authors indicate that the product is not water soluble or can be homogenously distributed by an emulgator.
In the test, some deposits were noted as well as swirling material.

Reported statistics and error estimates:

No data.

Validity criteria fulfilled:

not specified

Conclusions:

Study in principle according to guideline, some data are lacking, incl full composition. Stability, vapour pressure and actual concentrations are missing. Due to the fact the substance was tested at maximum water solubility and no mortalities occurred, it is justified to conclude the substance will not affect daphnids. Based on nominal concentrations the conclusion is correct, but could be re-phrased into "at maximum water solubility the substance does not cause mortality under the conditions of the test".

Executive summary:

In this study, test substance Basoplast 20 konz. was tested for its toxicity to the waterflea, Daphnia magna in a static system after 48 h exposure. The study was carried out according to EU guideline C2 of Annex V to 79/831/EEC with 4 times 5 animals per concentration level. Nominal concentrations were 0 - 62.5 - 125 - 250 - 500 mg/L. No mortalities were noted during the study in which presumed undissolved material was observed in the test solutions containing the test substance. The EC50 was therefore concluded at > 500 mg/L and the NOEC was determined at 500 mg/L both based on nominal concentrations.

Description of key information

Key study is BASF Aktiengesellschaft (1989). Study performed according to EWG 79/831/C.2 with Daphnia magna, 48h. Non GLP. Conclusion regarding EC50 reliable. EC50 > 500 mg/L, based on nominal concentration, however should be concluded at maximum water solubility. Several restrictions as to the study.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

500 mg/L

Additional information

Due to the fact the substance was tested at maximum water solubility and no mortalities occurred, it is justified to conclude the substance will not affect daphnids.

Water solubility data indicate low solubility. Data are lacking wrt stability and vapour pressure, no actual concentrations were determined. Substance identity and composition data are insufficient, no positive control to confirm sensitivity of test/batch of daphnids.