1-[(2-hydroxyethyl)thio]propan-2-ol

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:

From 04 August 2017 to 11 October 2017

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)

Deviations:

yes

Remarks:

See 'Principales of method if other than guideline'

Principles of method if other than guideline:

The temperature of the test room varied by more than 1°C. This is not expected to affect the results of the test as the temperature remained within 18-22°C and no significant mortality was observed in the controls. The D. magna used in the range-finding test were up to 48h old at test initiation. This was due to poor yield from the ephippia at 72h. This is not expected to affect the results of the test as the range-finding test is only used to determine the concentrations which the definitive test will use. The D. magna used in the definitive test were hatched from ephippia, rather than sourced from live adults. This is not expected to affect the results of the test.

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Dilution series

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Source: hatched from ephippia sourced from MicroBio Tests

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Remarks on exposure duration:

Observations were recorded at 24 hours and 48 hours of exposure to test substance

Hardness:

Not specified

Test temperature:

20 +/- 2°C

pH:

6 - 9

Dissolved oxygen:

8.69-8.97 mg/l

Nominal and measured concentrations:

Nominal concentrations: 1, 10, 100, and 1000 mg/L.

Details on test conditions:

TEST SYSTEM
- Test vessel: borosilicate glass crystallising dishes
- Type: closed
- Material, size, headspace, fill volume: 100 ml
- Aeration: No aeration during the 48 hour study
- Type of flow-through: static
- No. of organisms per vessel: 10 animals per vessel
- No. of vessels per concentration (replicates): 2 vessels per concentration
- No. of vessels per control (replicates): 2 vessels per control
- No. of vessels per vehicle control (replicates): 2 vessels per control

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: ISO reconstituted water (as specified in OECD 202)
- Intervals of water quality measurement: Carried out at each concentration at 0h and 48h

EFFECT PARAMETERS MEASURED: Immobilisation

OTHER TEST CONDITIONS
- Photoperiod: 16h light / 8h dark

RANGE-FINDING STUDY
- Test concentrations: 1000, 100, 10 and 1 mg/l
- Results used to determine the conditions for the definitive study: yes

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

1 920 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

2 830 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

320 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Behavioural abnormalities: None reported
- Observations on body length and weight: None reported
- Mortality of control: < 10% control mortality observed
- Abnormal responses: None reported

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- Relevant effect levels: Yes
- Limit test: No
- Dose-response test: Yes
- ECx: 24h EC50 = 1.16 mg/L

Reported statistics and error estimates:

Results for both range-finding and definitive tests were calculated by Linear Interpolation within the CETIS suite of statistical analysis.

Validity criteria fulfilled:

yes

Conclusions:

The 48-hour EC50 was 1,920 mg/L and the 48-hour NOEC 320 mg/L. The substance did not meet the criteria for classification as toxic to the aquatic environment according to Regulation (EC) N° 1272/2008.

Executive summary:

The short-term toxicity of 1-[(2-hydroxyethyl)thio]propan-2-ol to aquatic invertebrates was determined during a GLP-compliant study performed according to the OECD Testing Guideline 202.

The species was Daphnia magna.

A range-finding test was performed to determine the concentrations to be used during the definitive test. As a result of this range-finding test, concentrations of 100, 320, 1,000, 3,200 and 10,000 mg/L were used during the definitive test.

The 48-hour EC50 was 1,920 mg/L and the 48-hour NOEC 320 mg/L. The substance did not meet the criteria for classification as toxic to the aquatic environment according to Regulation (EC) N° 1272/2008.

Description of key information

The short-term toxicity of 1-[(2-hydroxyethyl)thio]propan-2-ol to aquatic invertebrates was determined during a GLP-compliant study performed according to the OECD Testing Guideline 202.

The species was Daphnia magna.

A range-finding test was performed to determine the concentrations to be used during the definitive test. As a result of this range-finding test, concentrations of 100, 320, 1,000, 3,200 and 10,000 mg/L were used during the definitive test.

The 48-hour EC50 was 1,920 mg/L and the 48-hour NOEC 320 mg/L. The substance did not meet the criteria for classification as toxic to the aquatic environment according to Regulation (EC) N° 1272/2008.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

1 920 mg/L