ε-Caprolactone, oligomeric reaction products with 2,2'-oxydiethanol

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:

Experimental period: 15 to 17 August 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

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Concentrations: Control, 4.6, 10, 22, 46 and 100 mg/L (test substance as received)
- Sampling method: All samples were diluted with dilution water to within calibration range and centrifuged prior to analysis
- Sample storage conditions before analysis: No data

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Water-accommodated fraction (WAF). Nominal amounts of test item mixed with dilution water, shaken vigorously for 24 hours. After shaking test solutions were put in an ultrasonic bath for 30 mins, then centrifuged at 4500 rpm for 10 mins.
- Eluate: Dilution water (according to OECD 202)
- Differential loading: No
- Controls: Dilution water only
- Evidence of undissolved material (e.g. precipitate, surface film, etc.): No data

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain/clone: No data
- Source: Laboratory culture
- Age of parental stock (mean and range, SD):
- Feeding during test: Not applicable

ACCLIMATION
- Acclimation period: Not applicable

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

2.502 mmol/L (nominal)

Test temperature:

20.9 - 23.0oC

pH:

7.7 - 7.9

Dissolved oxygen:

8.2 - 9.1

Salinity:

No data

Conductivity:

No data

Nominal and measured concentrations:

Nominal concentration: 4.6, 10, 22, 46 and 100 mg/L
Measured (DEG-2ECL): 5.0, 11.8, 23.3, 49.2 and 105.8 mg/L
Measured (DEG-3ECL): 2.3, 8.0, 17.2, 41.8, 94.6 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: glass beakers
- Type (delete if not applicable): open / closed
- Material, size, headspace, fill volume: glass beakers, nominal volume 50 mL
- Aeration: No
- 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: Standard dilution medium (OECD 203)

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16:8 hours light:dark
- Light intensity: No data

Reference substance (positive control):

no

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 105.8 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: Based on component DEG-2ECL

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 94.6 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: Based on component DEG-3ECL

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

>= 105.8 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: Based on component DEG-2ECL

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

>= 94.6 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: Based on component DEG-3ECL

Nominal concentration (mg/L)	Geometric mean measured concn DEG‑3ECL (mg/L)	Total no. Daphnia introduced	Total no. immobilised		Total % immobilised
			24 hour	48 hour
Control	-	20	0	0	0
4.6	2.3	20	0	0	0
10	8.0	20	0	0	0
22	17.2	20	0	0	0
46	41.8	20	0	0	0
100	94.6	20	1	2	10

Validity criteria fulfilled:

yes

Conclusions:

The 48-hour EC50 (immobility) for Daphnia magna was determined to be >105.8 mg/l and >94.6 mg/l based on geometric mean measured concentrations of two components of the test substance.

Executive summary:

A 48-hour acute toxicity study with the aquatic invertebrate Daphnia magna was conducted in accordance with the OECD test guideline 203 and in compliance with GLP. The test was performed at nominal concentrations of 4.6, 10, 22, 46 and 100 mg/l of a water‑accommodated fraction (WAF) under semi-static conditions. The test substance is UVCB but unstable in test medium. Two components (DEG-2ECL and DEG-3ECL) were measured analytically. Results are reported based on both analysed components.

The 48-hour EC50 values were determined to be >105.8 and >94.6 mg/l for the two components, based on geometric mean measured concentrations.

Only 10% mortality was observed at the highest tested concentration, which is within the maximum allowed by the test guideline, and was not considered to be significant.

Under the conditions of the test, the 48-hour EC50 (immobility) was determined to be >105.8 and >94.6 mg/l, with the lower number being relied on in PNEC development.

Description of key information

A reliable acute toxicity study with the aquatic invertebrate Daphnia magna and using the test substance ε-Caprolactone, oligomeric reaction products with 2,2’-oxydiethanol is available. The 48-hour EC50's were determined to be >105.8 and >94.6 mg/l based on geometric mean measured concentrations of two components of the test substance. These values are taken as the short-term toxicity in aquatic invertebrates endpoint, although the PNEC derivation relies on the lower of these two values for precautionary purposes.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

94.6 mg/L

Additional information

A 48-hour acute toxicity study with the aquatic invertebrate, Daphnia magna, was conducted in accordance with the OECD test guideline 203 and in compliance with GLP. The test was performed at nominal concentrations of 4.6, 10, 22, 46 and 100 mg/l of a wateraccommodated fraction (WAF) under semi-static conditions. The test substance is UVCB, but unstable in the test medium. Two components (DEG-2ECL and DEG-3ECL) were measured analytically with results reported for both components. The 48-hour EC50 values are >105.8 mg/l and >94.6 mg/l for the two components. Only 10% mortality was observed at the highest tested concentration, which is within the maximum allowed by the test guideline, and inhibition was not considered to be significant.

Under the conditions of the test, the 48-hour EC50 (immobility) was determined to be >105.8 mg/l and >94.6 mg/l, with the lower number being relied on in PNEC development