2-(2-methylpropoxy)ethanol

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:

31 January 2018 - 15 February 2018

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:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Dilution series
- Evidence of undissolved material (e.g. precipitate, surface film, etc.): Substance observed to be soluble in water.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Dapnia magna
- Source: Eco Cheshire Solutions
- Age of parental stock (mean and range, SD): Not reported
- Feeding during test: Animals were not fed during the test

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test temperature:

20 °C +/-2 °C, Constant within 1 °C

pH:

6-9

Dissolved oxygen:

>3 mg/l

Conductivity:

1.15 µS/cm

Nominal and measured concentrations:

Nominal concentrations: 100, 320, 1000, 3200 and 10,000 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: borosilicate glass crystallising dishes
- Type: closed
- Material, size, headspace, fill volume: 50 ml of test medium placed in 100 ml capacity test vessel
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: ISO Reconstituted Test Water without additives
- Conductivity: 1.15 µS/cm
- pH: 7.56
- Temperature 18.7C
- Dissolved oxygen 9.15 mg/L
- Intervals of water quality measurement: 0 and 48h

OTHER TEST CONDITIONS
- Adjustment of pH: If, at 0h, the pH of the dilution water was out-with the pH range of 8± 0.3; the pH was returned to within these limits by adjustment with either 1M HCl or NaOH as is appropriate.
- Photoperiod:16h light / 8h dark
- Light intensity: 453 lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :No. of immobile animals expressed as a portion of the total exposed. An animal is regarded as immobile if, after gentle stimulation, no movement was visible after 10 seconds. Animals were observed at 24h and 48h.

RANGE-FINDING STUDY
- Test concentrations: 1, 10, 100 and 1000 mg/L
- Results used to determine the conditions for the definitive study: 48h EC50 >1000 mg/L

Reference substance (positive control):

yes

Remarks:

potassium dichromate (K2Cr2O7)

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

2 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

2 380 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

1 000 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
- Other biological observations: None reported
- Mortality of control: <10%
- Other adverse effects control: None reported
- Abnormal responses: None reported
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: No
- Effect concentrations exceeding solubility of substance in test medium: No

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- Relevant effect levels: 24h EC50 0.6-2.1 mg/L
- Dose-response test: 0.32, 0.56, 1.0, 1.8, 3.2 and 100 mg/L
- 24h EC50: 1.27 mg/L

Reported statistics and error estimates:

The result was based on nominal concentrations and was calculated by Linear Interpolation within the CETIS (v1.8) suite of statistical analysis.

Validity criteria fulfilled:

yes

Conclusions:

The 48-hour EC50 was 2100 mg/L and the 48-hour NOEC was 1000 mg/L. Based on the results of this study the substance did not meet the criteria for classification as acutely toxic to the aquatic environment according to Regulation (EC) N° 1272/2008.

Executive summary:

The short-term toxicity of 2-(2-methylpropoxy)ethanol to freshwater crustacean Daphnia magna was determined in a GLP compliant study in accordance with OECD 202 test guideline. A preliminary range-finding test was conducted at concentrations of 1, 10, 100 and 1000 mg/L. The 48h EC50 for the range-finding test was calculated to be >1000 mg/L and as a result the following concentrations were chosen for the definitive test: 100, 320, 1000, 3200 and 10000 mg/L. The 48h EC50 and 48h NOEC were 2100 mg/L and 1000 mg/L respectively. A reference test was conducted concurrently using potassium dichromate. The study met all relevant validity criteria. As the 48-hour EC50 is greater than 1 mg/L, the registered substance is not considered to be a acutely toxic to aquatic invertebrates (CLP Regulation (EC) No 1272/2008).

Description of key information

The short-term toxicity of 2-(2-methylpropoxy)ethanol to freshwater crustacean Daphnia magna was determined in a GLP compliant study in accordance with OECD 202 test guideline. Daphnia magna were exposed to the substance at concentrations of 100, 320, 1000, 3200 and 10000 mg/L. The 48h EC50 and 48h NOEC were 2100 mg/L and 1000 mg/L respectively. As the 48-hour EC50 is greater than 1 mg/L, the registered substance is not considered to be a acutely toxic to aquatic invertebrates (CLP Regulation (EC) No 1272/2008).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

2 100 mg/L