Sodium 2-butoxyethyl sulphate

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:

15 Aug – 13 Sep 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)

Version / remarks:

adopted: 13 April 2004

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Landesanstalt für Umwelt, Messungen und Naturschutz Baden-Württenberg, Germany

Analytical monitoring:

yes

Details on sampling:

- Concentrations: Control and 100 mg/L
- Sampling method: 10 mL samples were taken at test start and test end (48h); All samples and the control were stabilized (1:1) with acetonitrile
- Sample storage conditions before analysis: All samples were stored deep frozen

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: test item was solved in test medium by shaking and test solutions were prepared by dilution of appropriate solutions with test medium.
- Controls: yes, medium only

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water flea
- Strain/clone: Straus Clone V
- Feeding during test: no
- Food type: Single cell green algae (Desmodesmus subspicatus, formerly Scenedesmus subspicatus)
- Frequency: at least three times a week

METHOD FOR PREPARATION AND COLLECTION OF EARLY INSTARS OR OTHER LIFE STAGES: Freshly hatched daphnids (not the first brood) less than 24 h old were used for the test

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

13°dH (232 mg/L as CaCO3)

Test temperature:

19.8 – 20.2 °C

pH:

7.77 – 7.99 (control)
7.78 - 8.07 (100 mg/L)

Dissolved oxygen:

7.8 - 9.0 mg/L (control)
8.6 - 9.1 mg/L (100 mg/L)

Nominal and measured concentrations:

Control and 100 mg/L (nominal)

Details on test conditions:

TEST SYSTEM
Test vessel:
- Type: open (covered with a glas plate)
- Material, size, headspace, fill volume: 100 ml glass vessel, filled with approx. 50 mL, 50 mL headspace
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- Biomass loading rate: approx. 10 mL of test solution for each animal

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Elendt medium was used as test medium (according to OECD 202)
- pH: 7.92
- Culture medium different from test medium: no
- Intervals of water quality measurement: Physical-chemcal parameters were measured at test start and after 24 and 48 h.

OTHER TEST CONDITIONS
- Photoperiod: 16 h photoperiod /8 h darkness daily
- Light intensity: 150 lux (mean at test start)

EFFECT PARAMETERS MEASURED: immobility at 24 and 48 h

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Behavioural abnormalities: After 48 h of exposure no immobilisation was observed in all test item concentrations
- Mortality of control: After 48 h of exposure no immobilisation was observed in the control
- Other: Biological and analytical results are summarized within the tables 1-3 in section "Any other information on results incl tables".

Results with reference substance (positive control):

The results indicate an EC50 (24 h) of the reference item potassium dichromate around 1.00 mg/L (in accordance with the requirements of the OECD guideline 202).

Reported statistics and error estimates:

The NOEC was established based on the highest concentration at which the immobilisation is not higher than the allowed control immobilisation (≤10% immobilisation).

Table 1:  Determined concentration of Test Item

Test item	Sodium 2-butoxyethyl sulphate	Sampling	Test Item
nominal [mg/L]	nominal [mg/L]	[h]	[mg/L]	% of nominal
Control	0	0 fresh	n.d.	-
		48 aged	n.d.	-
100	100	0 fresh	102	102
		48 aged	106	106

 - = not calculated; n.d. = not detectable; LOQ = 1.00 mg/L Test Item

Table 2: Results of the test, 48 h values

	Control	100 mg/L
	Immobilised daphnids after 48 h
Group 1	0	0
Group 2	0	0
Group 3	0	0
Group 4	0	0
∑	0	0
%	0	0

 

Table 3: Determined concentration of the test item

Test item	Test Item	Sampling	Test Item
nominal [mg/L]	nominal [mg/L]	[h]	[mg/L]	% of nominal
Control	0	0 fresh	n.d.	-
		48 aged	n.d.	-
100	100	0 fresh	102	102
		48 aged	106	106

 - = not calculated; n.d. = not detectable; LOQ = 1.00 mg/L Test item

Table 4: Validity criteria

Criterion from the guideline	Outcome	Validity criterion fulfilled
In the control, including the control containing the solubilising agent, not more that 10% of the daphnids should have been immobilized.	0%	yes
The dissolved oxygen concentration at the end of the test should be ≥ 3 mg/L in control and test vessels.	≥ 7.8 mg/L	yes

Validity criteria fulfilled:

yes

Conclusions:

No effects were observed up to the test item concentration of 100 mg/L therefore the EC50 was determined to be at >100 mg/L and the NOEC at 100 mg/L.

Description of key information

EC50 (48h) >100 mg/L (Daphnia magna, OECD 202, nominal)

Additional information

One study is available, in which the short term toxicity to invertebrates was investigated according to GLP and OECD guideline 202 (Eurofins, 2017b). The test was performed with a test item concentration of 100 mg/L in a static test system with the test organism Daphnia magna. The initial measured content of the test item was 102% of nominal and the aged measured content was 106% of nominal. Therefore the results are given based on nominal concentrations. Since no effects were observed the EC50 (48 h) was determined to be > 100 mg/L.