Octan-1-ol, ethoxylated

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:

04 Feb - 08 Mar 2019

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)

Version / remarks:

April 2004

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Concentrations: Samples were taken initial from the test preparation and from pooled replicates after 48 h.
- Sample storage conditions before analysis: no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
A nominal amount of test item (100 mg) was dissolved in test water and the volume adjusted to 1 liter to give the 100 mg/L test concentration from which a series of dilutions was made to give further test concentrations of 56, 32, 18 and 10 mg/L.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Source: in-house labroatory breeding
- Age: less than 24 hours
- Feeding during test: no

CULTURE
- Culture conditions: Same as in test
- Type and amount of food: algal suspension (Pseudokirchneriella subcapitata) and GM300 fish food suspension.
- Feeding frequency: daily

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test temperature:

20 - 21 °C

pH:

control: 7.7 - 8.1
test concentrations: 7.9 - 8.4

Dissolved oxygen:

8.4 - 9.5 mg/L

Nominal and measured concentrations:

Nominal test substance concentrations: 10, 18, 32, 56 and 100 mg/L.
Measured test concentrations (initial): 9.89, 15.6, 30.5, 55.5, and 96.2 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: glass vessels (50 mL nominal volume)
- Type (delete if not applicable): test vessels were covered
- Fill volume: 100 mL
- Aeration: none
- No. of organisms per vessel:5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: reconstituted water (Elendt M7 medium)
- Culture medium different from test medium: no
- Intervals of water quality measurement: daily

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16:8 day/night
- Light intensity: between 200 and 1200 Lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : mobility after 24 and 48 hours

RANGE-FINDING STUDY
- Test concentrations: 0.1, 1.0, 10 and 100 mg/L
- Results used to determine the conditions for the definitive study: 100% immobilisation at 100 mg/L
Sub lethal effects of exposure were observed. Trapping at the surface was observed in one control Daphnia and one Daphnia at the test concentration of 10 mg/L was pale.

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

40 mg/L

95% CI:

>= 35 - <= 46

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

18 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

15.6 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Behavioural abnormalities: After 24 h: reduced mobility and pale at 56 mg/L. After 48 h: reduced mobility and pale at 32 and 56 mg/L.
- Mortality of control: no
- Other adverse effects control: Trapping at the surface was observed in one control Daphnia.

Results with reference substance (positive control):

EC50(48 h): 0.80 mg/L
The positive control was conducted between 25 September 2018 and 27 September 2018.

Reported statistics and error estimates:

EC50 values: Probit analysis using Linear Maximum Likelihood regression.
LOEC and NOEC values: Calculated using the ToxRat Professional computer software package (TOXRAT).

Validity criteria fulfilled:

yes

Remarks:

For further details please refer to table 3 in “Any other information on results incl. tables”.

Description of key information

EC50 (48 h): 40 mg/L (nominal), OECD 202