2,2'-(ethylenedioxy)diethanol

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
See attached justification document 'update_Category Justification_ethylene glycol and higher glycols_2022.doc'

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
See above.

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
See above.

3. ANALOGUE APPROACH JUSTIFICATION
See above.

4. DATA MATRIX
See above.

Reason / purpose for cross-reference:

read-across: supporting information

Reason / purpose for cross-reference:

read-across: supporting information

Reason / purpose for cross-reference:

read-across: supporting information

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

analytically verified

Basis for effect:

mortality

Remarks on result:

other: Daphnia magna

Remarks:

CAS 107-21-1, BASF AG, 1997

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

65 980 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

analytically verified

Basis for effect:

mortality

Remarks on result:

other: Hyalella azteca

Remarks:

CAS 111-46-6, PTAC, 2006

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

62 630 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

analytically verified

Basis for effect:

mobility

Remarks on result:

other: Daphnia magna

Remarks:

CAS 111-46-6, PTAC, 2006

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods with acceptable restrictions

Remarks:

Study conducted according to Environment Canada test method.

Qualifier:

according to guideline

Guideline:

other: Test for Survival and Growth in Sediment Using the Freshwater Amphipod Hyalella azteca, EPS 1/RM/33 (EC 1997)

Principles of method if other than guideline:

Environment Canada test method

GLP compliance:

not specified

Analytical monitoring:

yes

Details on sampling:

- Concentrations: Samples from the control, low, medium and high treatments were collected at the start and end of each test, and analysed

Vehicle:

no

Details on test solutions:

- The stock and test solutions were prepared in SAM-5S reconstituted water as per Borgmann, 1996.
- The water was aerated at test temperature at least overnight prior to use in the test.

Test organisms (species):

other aquatic crustacea: Hyalella azteca

Details on test organisms:

TEST ORGANISM
- Feeding during test
- Food type: YCT
- Amount: 1.3 mL
- Frequency: on Day 0 and 0.5 mL on Day 2 of the test.

ACCLIMATION
- Acclimation period: for 5 days prior to use in the tests
- Acclimation conditions (same as test or not): same
- Type and amount of food: 10 mL each of YCT and Tetrafin
- Feeding frequency: twice daily
- Health during acclimation (any mortality observed): Total mortality during this period was 1.25%.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

124 mg/L as CaCO3 (measured by EDTA titration)

Test temperature:

21 - 25 °C

Nominal and measured concentrations:

Five nominal test concentrations and a control were tested. Analytical recovery of the test concentrations at test start and end were generally within 20% of nominal concentrations: 83-90%

Details on test conditions:

TEST SYSTEM
- Test vessel: 250 mL glass beaker
- Type: The test chambers were covered with a plexiglass sheet
- Fill volume: 200 mL
- Aeration: The water was aerated at test temperature at least overnight prior to use in the test.
- Renewal rate of test solution: Test solutions were not renewed during the tests.
- No. of organisms per vessel: 10
- No. of vessels per concentration: 4
- No. of vessels per control: 4

TEST MEDIUM / WATER PARAMETERS
- Source/ preparation of dilution water: The stock and test solutions were prepared in SAM-5S reconstituted water as per Borgmann, 1996. This water was prepared by adding 8.82 g CaCl2•2H2O, 1.81 g MgSO4, 0.06 g NaBr, 5.04 g NaHCO3, 0.22 g KCl to 60 L of deionised water.
- Alkalinity: 53 mg/L as CaCO3

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

EFFECT PARAMETERS MEASURED:
The test chambers were monitored on Days 2 and 4 for number of dead neonates. Measurements of dissolved oxygen concentrations, temperature, and pH, were taken at the start and end of the test. Conductivity was measured at test initiation.

Reference substance (positive control):

yes

Remarks:

copper sulphate

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

43 500 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

analytically verified

Basis for effect:

mortality

Remarks on result:

other: CI95%:39400 - 48100

Results with reference substance (positive control):

The resulting LC50 (203 μg Cu/L with 95% confidence limits of 177 and 233 μg/L) were within two standard deviations of previous tests (35 and 389 μg/L).

Reported statistics and error estimates:

The 96-hr LC50 with 95% confidence limits were calculated using the trimmed Spearman-Karber (0-10% trim) method or maximum likelihood probit method in the statistical program, ToxCalc™ (Version 5.0.23j), a Microsoft Excel-based software application (Tidepool Scientific Software 1994-2006).

The tests were considered valid as none of control amphipods died or displayed atypical or stressed behaviour during the test. A reference toxicant (positive control) test was conducted with copper sulphate. The resulting LC50 (203 µg Cu/L with 95% confidence limits of 177 and 233 µg/L) were within two standard deviations of previous tests (35 and 389 µg/L).

Validity criteria fulfilled:

yes

Reference 3

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

(Q)SAR

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

1. SOFTWARE
Estimation Programs Interface (EPI) Suite for Microsoft Windows, v4.11 (US EPA, 2012)

2. MODEL (incl. version number)
ECOSAR v2.00

3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
See section 'Test Material'.

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
See attached QMRF.

5. APPLICABILITY DOMAIN
See attached QPRF.

6. ADEQUACY OF THE RESULT
- The model is scientifically valid (see attached QMRF).
- The model estimates the toxicity to aquatic organisms: Daphnids: 48-h EC50; this data can be used to support the assessment regarding the toxicity of a substance to
aquatic organisms (see also attached QPRF).

Qualifier:

no guideline followed

Principles of method if other than guideline:

ECOSAR v2.00: Estimation of acute toxicity to Dpahnid for chemical class "Neutral Organic SAR (Baseline Toxicity)"

GLP compliance:

no

Test organisms (species):

other: Daphnid

Water media type:

freshwater

Total exposure duration:

48 h

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

115 220 mg/L

Nominal / measured:

estimated

Conc. based on:

act. ingr.

Basis for effect:

mortality

Remarks on result:

other: ECOSAR chemical class: "Neutral Organic SAR (Baseline Toxicity)"; The substance is in the applicability domain of the model.

Description of key information

With high probability the test substance is acutely not toxic to aquatic invertebrates.

Additional information

For the assessment of short-term toxicity of the substance to aquatic invertebrates a read-across approach was used along with the available supporting experimental and estimated data for the substance itself. This read-across approach is consisted of available experimental data for two structurally similar substances (CAS 107 -21 -1 and CAS 111 -46 -6)

To determine the toxicity of ethylene glycol (CAS 107 -21 -1) on aquatic invertebrates the study were performed by BASF AG (1998). This study was performed according to OECD TG 202 with Daphnia magna as the test organism. The test concentrations were analytically verified.

The analytical recovery rate was in all analyzed test solutions above 80%.

The 48 -h EC50 for Daphnia was > 100 mg/L (the highest tested concentration, nominal). 

To determine the toxicity of diethylene glycol (CAS 111 -46 -6) on aquatic invertebrates two studies were performed by PTAC (Petroleum Technology Alliance Canada,2006) One key study was performed according to Environment Canada test method (EPS 1/RM/11) with Daphnia magna as the test organism.The 48 -h EC50 for Daphnia wasdetermined to be 62630 mg/L (nominal, analytically verified). The second key study was performed according to another Canada test method (EPS 1/RM/33) with the amphipod Hyalella azteca as the test organism. The 96 -h LC50 was determined to be 65980 mg/L (nominal, analytically verified).The test concentrations were analytically verified in both studies.The analytical recovery rate was in all analyzed test solutions was in the range between 84% and 105%.

These results are supported with the estimated value for CAS 112 -27 -6, wich was derived from a valid QSAR model (ECOSAR v2.0; BASF SE, 2022). The 48 -h LC50 for the substance was predicted to be 115220 mg/L. The substance was within the applicability domain of the model.

Overall, it can be concluded that with high probability the test substance is acutely not harmful to aquatic invertebrates.

In addition, a supporting study is available for the test substance itself that investigated the short-term toxicity to aquatic crustacea (Hyalella azteca) (PTAC, 2006). Test organisms were exposed to five test concentrations of the test substance and a control for 96 hours under freshwater static conditions. Analytical recovery of the test concentrations at test start and end were generally within 20% of nominal concentrations: 83-90%. Therefore, effect levels are reported as nominal. The 96-h LC50 for the test substance was determined to be 43500 mg/L.

Overall, it can be concluded that with high probability the test substance is acutely not harmful to aquatic invertebrates.