3-ethyloxetane-3-methanol

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:

2009

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Does not meet important criteria of test guideline (e.g. confirmatory analysis of test solutions not reported). Even though there are deficiencies within the study, nominal test concentration greatly exceeded the maximum guideline test concentration required (100 mg/L), as a result it can be concluded that the test substance is not toxic to Daphnia.

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

Not reported. Samples of the stock solution and the highest tested concentration at 0 h and 48 h were collected and stored in the freezer until analysed by the sponsor. No results have been presented to confirm concentrations were achieved.

Vehicle:

no

Details on test solutions:

10 001,1 mg of the test item was added to 1000 mL reconstituted test water (dilution water) and stirred on the day of the test start. Since floccule was observed, the solution was membrane filtered. The filtrate was used as stock solution (approx. 10000 mg/L). The test solutions were made by dilution of the stock solution with reconstituted test water.

Test organisms (species):

Daphnia magna

Details on test organisms:

The test used newly hatched animals, 6 to 24 hours old, that were incubated for 48 hours in a gradient of the test item. The animals were taken from Toxicon's continuous culture of Daphnia magna.

The culture originates from DHI, Denmark, and is on working days fed with approximately 50-75 mL green algae Pseudokirchneriella subcapitata.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

Not applicable

Hardness:

250±25 mg/L (expressed as CaC03).

Test temperature:

21±1° C

pH:

7.99 to 8.09

Dissolved oxygen:

95.9 to 101.6%

Salinity:

Not applicable

Nominal and measured concentrations:

Nominal concentrations: Control, 2000; 4000; 6000; 8000 and 10000 mg/L.

Details on test conditions:

Reconstituted test water, as specified in OECD TG no. 202, was used as dilution water (specified below). In the controls, only reconstituted test water was used. The animals were incubated in glass Petri dishes (50 mL), with 25 mL solution. Four replicates, with five animals in each replicate, were used for both the test concentrations and for the control. The dishes were incubated in a thermo constant room at a temperature of 21±1° C and subdued light with the light period of 16 hours light: 8 hours darkness. Before the experiment start, pH and oxygen saturation was measured in all the solutions. The numbers of immobilised animals were observed at 24 and 48 hours in all the test dishes. At the end of the experiment pH and oxygen saturation were measured in all the test groups (4 pooled replicates/group).

Reference substance (positive control):

yes

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

6 910 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 10 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

4 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Results with reference substance (positive control):

A qualification test on the Daphnia magna culture was made on the 15th of May 2008 to assure the quality of the test animals. EC50 was 1,3 mg/1, which confirmed that the culture was suitable as a test organism according to OECD TG no. 202

Reported statistics and error estimates:

An EC50-value of 6910 mg/L was determined (by graphic interpolation) for the 48 hours of exposure for the test item TMPO

Conclusions:

An EC50-value of 6910 mg/L was determined (by graphic interpolation) for the 48 hours of exposure for the test item TMPO

The NOEC was 4000 mg/L

Executive summary:

Due to the lack of analytical chemistry the data is insufficient for convincing expert judgment to conclude that test conditions were maintained satisfacatorily. Even though there are deficiencies within the study, nominal test concentration greatly exceeded the maximum guideline test concentration required (100 mg/L), as a result it can be concluded that the test substance is not toxic to Daphnia and therefore it is considered that conclusions can be drawn from the report.

Description of key information

The 48-hour EC50 was found to be 6910 mg/l, thereby exceeding the normal highest dose recommended for such studies (1000 mg/L). Therefore, in the chemical safety assessment performed according to Article 14(3) in connection with Annex I section 3 (Environmental Hazard Assessment) no hazard was identified, therefore no PNEC can be derived.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

6 910 mg/L

Additional information

A 48 -hour acute Daphnia magna toxicity test was carried out for 3-ethyloxetane-3-methanol according to OECD guideline 202. The 48-hour EC50 was 6910 mg/l.