Alcohols, C12-14 (even-numbered), ethoxylated, magnesium salts, < 2.5 mol EO

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:

05 May - 30 June 2022

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 April 2004

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Concentrations: All concentrations including the control
- Sampling method: At the start of the test (0 hour), 5 mL new media samples were taken from the freshly prepared control and test media flasks. At 24h and at the end of the test period (48 hours), 5 mL old media samples were taken from pooled control and test vessels. The samples were taken using an air displacement pipette fitted with a plastic pipette tip into 20 mL glass scintillation vials containing 5 mL of methanol.
- Sample storage conditions before analysis: no, samples were analysed on the day of receipt

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Astock solutionwas prepared by adding 37.49 – 37.53 mg of test substanceto 500 mL of autoclaved Elendt M4 medium. The test solutions were prepared by serial dilution of the stock solution.
- Other relevant information: The test media and the control were checked for the tyndall effect using a Hach 2100 N turbidity meter. The turbidity measurement for the test solution was not significantly different to the measurement for the control and therefore the test solution was considered a true solution.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Age at study initiation (mean and range, SD): < 24 h
- Method of breeding: cultured in 1 litre glass beakers containing 1000 mL of Elendt M4 medium. Fed daily with a concentrated suspension of Chlorella vulgaris
- Source: in-house culture setup originally from dormant eggs (ephippia) supplied by MicroBioTests Inc., Belgium
- Feeding during test: no

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test temperature:

19.3 – 20.0 °C

pH:

7.52 – 8.89

Dissolved oxygen:

≥ 7.72 mg/L

Nominal and measured concentrations:

Nominal test concentrations: 0.8, 1.8, 4.0, 8.8 and 19.4 mg a.i./L

For the individual components, recovery rates between 80 - 120 % of nominal were not maintained throughout the test as such, TWA were calculated at each concentration for each component. As the TWA concentrations were all within 80 - 120 % of nominal the EC50 values, the corresponding NOEC and LOEC values were determined based on nominal concentrations.

Details on test conditions:

TEST SYSTEM
- Test vessel: tall form beakers
- Type (delete if not applicable): covered with clear plastic petri dish lids
- Material, size: glass, 100 mL
- Volume of solution: 50 mL
- Aeration: no
- Renewal rate of test solution (frequency/flow rate): renewal at ca. 24 h
- 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: sterilised Elendt M4 medium
- Culture medium different from test medium: no
- Intervals of water quality measurement: at 0 and 48 h (continuously measurment of temperature)

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16-hour light: 8 hour dark cycle (fluorescent lighting)

EFFECT PARAMETERS MEASURED: Mobility after 24 and 48 hours

RANGE-FINDING STUDY
- Test concentrations: 0.1, 1, 10 and 100 mg a.i./L
- Results used to determine the conditions for the definitive study: LC50 (48h). 1.0- 10.0 mg a.i./L

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

6.17 mg/L

95% CI:

>= 5.41 - <= 7.04

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Remarks:

based on eight representative constituents

Basis for effect:

mobility

Details on results:

- Behavioural abnormalities: No
- Mortality of control: No
- Immobilisation of control: No
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: no precipitation observed. The test concentrations were noted to be colourless solutions during the test, with some foaming noted at the 8.8 and 19.4 mg a.i./L concentrations.

Results with reference substance (positive control):

- Results with reference substance valid? yes
- Dose-response test: yes
- 48 h-EC50: 1.48 mg/L (95% CI : 0.746 - 2.92)

Reported statistics and error estimates:

Statistical analysis was performed using the CETIS program v 1.8.6.8.
The NOEC and LOEC values were determined using Cochran-Armitage Trend Step-Down Test at 24 and 48-hours. The 48-hour effect concentration (EC50) was determined using a Trimmed Spearman-Kärber test. The 24-hour effect concentration (EC50) was determined empirically because ≥50% immobilisation was not seen at this timepoint.

Table 1: Time Weighted Average Concentrations

Percentage Recoveries Percentage Recovery (%)
Nominal Test Substance Concentration (mg a.i./L)	Magnesium dodecyl sulfate	Dodecan-1-ol, ethoxylated (1 EO), sulfate, magnesium salt	Dodecan-1-ol, ethoxylated (2 EO), sulfate, magnesium salt	Dodecan-1-ol, ethoxylated (3 EO), sulfate, magnesium salt	Magnesium tetradecyl sulfate	Tetradecan-1-ol, ethoxylated (1 EO), sulfate, magnesium salt	Tetradecan-1-ol, ethoxylated (2 EO), sulfate, magnesium salt	Tetradecan-1-ol, ethoxylated (3 EO), sulfate, magnesium salt
0.8	93.0	89.1	88.8	88.2	83.4	82.6	82.3	83.5
1.8	113	106	101	101	96.7	94.9	96.2	97.0
4	113	104	102	102	96.4	93.1	91.6	90.7
8.8	114	108	99.1	106	103	97.8	98.8	98.7
19.4	104	97.9	96.3	97.3	94.7	92.5	93.4	98.4

As all time weighted averages were within 80 – 120% of nominal for all components, nominal test substance concentrations were used to calculate the toxicity concentration.

 

Table 2: Results of the test, 48 h values 

Nominal Concentration [mg active ingredient/L]	Number of Daphnia magna exposed	Immobility at 24-hours [%]	Immobility at 48-hours [%]
Control	20	0	0
0.8	20	0	0
1.8	20	0	0
4	20	0	5
8.8	20	15	90
19.4	20	30	100

 

Table 3: Validity criteria for OECD 202 (2004)

Criterion from the guideline	Outcome	Validity criterion fulfilled
In the control, including the control containing the solubilising agent, not more than 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.	≥ 7.72 mg/L	Yes

 

Validity criteria fulfilled:

yes

Remarks:

Please refer to table 3 at "Any other information on results incl. tables"

Description of key information

EC50 (48 h): 6.17 mg a.i./L, nominal (D. magna, OECD 202)

Additional information

The assessment is based on the data currently available. New studies, based on the category review and the final decisions issued for some of the category substances, which are also relevant for this assessment, are currently being conducted. The hazard assessment with respect to aquatic toxicity will be updated once all ongoing studies have been finalised.

The acute toxicity of Alcohols, C12-14 (even-numbered), ethoxylated, magnesium salts, < 2.5 mol EO to aquatic invertebrates was investigated in a study following OECD GD 202. The test organism Daphnia magna was exposed to nominal test concentrations of 0.8, 1.8, 4.0, 8.8 and 19.4 mg a.i./L in a semi-static test approach. The test concentrations were analytically monitored by LC-TQMS. Eight constituents of the UVCB substance were targeted in the analysis. The determined EC50 (48 h) was 6.17 mg a.i./L, based on nominal exposure concentrations.