Ethylene carbonate

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2015-07-20 to 2015-09-11

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

yes

Remarks:

observations on the fish was carried out at 101 hours instead of 96 hours. This had no impact on the study results

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Sampling method: For analytical determination of test item concentrations:
* pH, water temperature and dissolved oxygen were recorded daily throughout the test.
* water samples were taken from the control and the 100 mg/L test vessel at 0 and 72 hours from fresh media and at 24 and 96 hours from old media
* duplicate samples and samples at 24 (fresh media), 48 (old and fresh media) and 72 hours (old media).
- Sample storage conditions before analysis: samples stored frozen for further analysis

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method:
* Range-finding test: The test item was dissolved directly in test water. Prior to use the test item was heated to 50°C (to aid weighing). A nominal amount of test item (4000 mg) was dissolved in test water and the volume adjusted to 1 L (stock solution). A series of dilution was made from the stock solution to give the required test concentrations of 1.0, 10 and 100 mg/L.
* Definitive test: Prior to use the test item was heated to 50°C in order to aid to weighing. A nominal amount of test item (2000 mg) was dissolved in test water and the volume adjusted to 500 mL to give a 4000 mg/L stock solution. The entire volume of this stock solution was added to 20 L of test water to give the required test concentration of 100 mg/L.
- Controls: yes
- Evidence of undissolved material (e.g. precipitate, surface film, etc): throughout the duration of the test, the test preparation were observed to be clear colorless solutions.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: rainbow trout
- Source: Brow Well Fisheries Limited; Hebden, near Skipton, Yorshire, UK and held at Envigo since 2015 08 04.
- Length at study initiation (length definition, mean, range and SD): 4.5 +/- 0.1 cm (mean +/- SD)
- Weight at study initiation (mean and range, SD): 1.123 +/- 0.13 g (mean +/- SD)
- Feeding during test: no
- Feeding during holding: commercial trout pellets which was discontinued ~24 hours prior the start of the definitive test..

ACCLIMATION
- Acclimation period: from 2015.08.25 to 2015.09.01
- Acclimation conditions (same as test or not): yes
- Type of food: Same as during holding
- Health during acclimation (any mortality observed): no mortality in the 7 days prior the start of the test.

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Post exposure observation period:

none

Hardness:

140 mg CaCO3/L (nominal)

Test temperature:

14°C

pH:

7.3-7.8

Dissolved oxygen:

8.8 - 9.91 mg O2/L

Salinity:

not applicable

Nominal and measured concentrations:

* Range-finding test:
- Nominal: Control, 1.0, 10, 100 mg/L
- Measured: ranging from 88 to 90% of nominal values
* Definitive test:
- Nominal concentration: 100 mg/L
- Measured: ranging from 89 to 91 % of nominal values

Details on test conditions:

TEST SYSTEM
- Test vessel: 25-30 L glass exposure vessels containing 20 L of test media
- Aeration: yes via narrow bore glass tubes
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: 0.43 g bodyweight/L

TEST MEDIUM / WATER PARAMETERS
- Standard test medium used according to guidelines
- Source/preparation of dilution water: laboratory tap water was dechlorinated by passage through an activated carbon filter and partly softened. Then the water was passed through a series of computer controlled plate heat exchangers to achieved te required temperature.

OTHER TEST CONDITIONS
- Photoperiod: 16L:8D, 20 min transition period
- Light intensity: no data

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): mortality after 3, 6, 24, 48, 72 and 96 h of exposure

TEST CONCENTRATIONS
- Spacing factor for test concentrations: none (limit test)
- Range finding study: yes
- Test concentrations: 1.0, 10 and 100 mg/L
- Results used to determine the conditions for the definitive study: yes

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

- 96-h NOEC = 100 mg/L
- There were no sub-lethal effects of exposure observed in 7 fish exposed to a test concentrations of 100 mg/L for a period of 96 hours.

Reported statistics and error estimates:

An estimate of the LC50 values was given by inspection of the mortality data

Validity criteria fulfilled:

yes

Conclusions:

A 96-h semi-static acute toxicity test with Rainbow trout (Oncorhynchus mykiss) was realised following OECD guideline (203) for Ethylene carbonate. The test resulted in a 96-h LC50 > 100 mg/L. The results of the test can be considered reliable without restriction.

Description of key information

The recently performed acute fish study of Ablitt (2015) was used as key study (Klisisch score of 1). The study was performed following the OECD 203 guideline. Following a range-finder study, the fish were exposed to a single test concentration of 100 mg/L. Analysis of the test preparations showed that the measured test concentration was near the nominal concentrations (<20% differences), so results were based on nominal test concentrations only. The test was performed under semi-static conditions and resulted in an unbounded 96-h LC50 > 100 mg/L for the fish Oncorhinchus mykiss. No effects were observed at the highest concentration tested.

The result is considered as key value for this endpoint and PNEC derivation.