2-butoxyethyl methacrylate

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:

Test phase 29-6-2020 to 3-7-2020

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:

Acclimatisation 7 days instead of 12 Test temp. 22.7 – 26.3oC. Fish stock tanks temp. 25.2 – 25.6oC

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch number of test material: F1-9K024C
- Expiration date of the lot/batch: September 2020
- Purity test date: 99.5

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: 4±2°C, protected from light
- Stability under storage conditions: stable
- Stability under test conditions: stable
- Solubility :395.7 mg/L

Analytical monitoring:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
Individual aliquots of 2-Butoxyethyl methacrylate (EC 236-885-7) were weighed into separate glass aquaria containing 15L of media. At 48 hours the solution was stirred for 46 hours and 15 minutes. The first 100 – 200ml of aqueous phase was discarded and then the required volume (10L) of the remaining aqueous fraction was removed for use in the test. This was regarded as the test media.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: Zebra Fish
- Source:University College London

ACCLIMATION
- Acclimation period: 7 days

FEEDING DURING TEST
- Not fed during the test.

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Test temperature:

22.7 – 23.9°C

pH:

8.44 to 8.80

Dissolved oxygen:

>88.3% ASV

Salinity:

0ppt

Nominal and measured concentrations:

0 (control) 3mg/l 5mg/l 8mg/l 13mg/l 17.5mg/l reported as nominal as received and are expressed as loading rates, following preparation of water accommodated fractions (WAF’s).

Details on test conditions:

TEST SYSTEM
- Test vessel: 10 litre volume aquaria (H=20.5cm, W=20.5cm, L=30.5cm)
- Material, size, headspace, fill volume: glass
- Renewal rate of test solution (frequency/flow rate): test solutions replaced after 48 hours, the remaining live animals being transferred to freshly prepared test solutions.
- No. of organisms per vessel: 4
- No. of vessels per concentration (replicates): 1 replicate at 0 (control), 3, 5, 8, 13 17.5 mg/l.
- No. of vessels per control (replicates): 1

TEST MEDIUM / WATER PARAMETERS
The pH (to 0.01), dissolved oxygen (to 0.1% ASV), salinity (to 1ppt) and temperature (to 0.1°C) were measured in each test and control solution immediately prior to initiating the test. The test parameters were measured daily, before and after the change of test solution on day 2 and at the end of the 96-hour exposure period

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
Observations of the test media were made every 24 hours and prior to and after the renewal of solutions on day 2. Observations of the test organisms for mortality and visible sub-lethal effects were made after 1 hour, 24, 48, 72 and 96 hours as close to test initiation time as possible.

TEST CONCENTRATIONS
- Range finding study
- Test concentrations: 2.0 and 17.4 mg/L
- Results used to determine the conditions for the definitive study: Initial results from this preliminary test indicated that the 96- hour EC50 was >17.4mg/l (by direct observation).

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LOEC

Effect conc.:

ca. 5 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

ca. 3 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: determined by direct observation as there was no mortality at 7.4mg/l. All calculations are based on nominal concentrations

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

ca. 4.592 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: (3.155 – 6.683mg/l LR)

Duration:

72 h

Dose descriptor:

LC50

Effect conc.:

ca. 4.592 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: LR (3.155 – 6.683mg/l LR)

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

ca. 4.592 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: LR (3.155 – 6.683mg/l LR)

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

ca. 4.773 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: LR (3.053 – 7.461mg/l LR)

Sublethal observations / clinical signs:

See attached result table

Validity criteria fulfilled:

yes

Conclusions:

The 96 hour LC50 value of 2-Butoxyethyl methacrylate (EC 236-885-7) to Zebra fish was estimated to be 4.592mg/l LR (determined by Trimmed Spearman-Karber, trim = 42.9%). The 0 and 96hr NOEC and LOEC were determined by direct observation to be 3 and 5mg/l respectively. The lowest concentration giving 100% mortality of Zebra fish was >17.45mg/l LR. The full water quality measurements are given in the summary tables in Appendix 1 and were within acceptable limits. Specifically, the dissolved oxygen concentration remained greater than 60% of the air saturation value, which fulfils the validity criteria of the study.
No analytical confirmation of the test substance concentrations was performed, therefore, as 2- Butoxyethyl methacrylate (EC 236-885-7) was insoluble in water, concentrations are expressed as nominal LR’s.

Executive summary:

This study was undertaken to investigate the acute toxicity of 2-Butoxyethyl methacrylate (EC 236-885-7) to Zebra fish (Danio rerio). The objective of this study was to determine the 96-hour LC50 value, which is defined as the concentration that kills 50% of exposed fish after a 96-hour exposure period.

Test No. 203, Acute Toxicity Test to fish, OECD Guidelines for the Testing of Chemicals, Section 2 was used.

The 96 hour LC50 value of 2-Butoxyethyl methacrylate (EC 236-885-7) to Zebra fish was estimated to be 4.592mg/L LR (determined by Trimmed Spearman-Karber, trim = 42.9%). The 0 and 96hr NOEC and LOEC were determined by direct observation to be 3 and 5mg/L respectively. The lowest concentration giving 100% mortality of Zebra fish was >17.45mg/L LR. The full water quality measurements are given in the summary tables in Appendix 1 and were within acceptable limits. Specifically, the dissolved oxygen concentration remained greater than 60% of the air saturation value, which fulfils the validity criteria of the study.

No analytical confirmation of the test substance concentrations was performed, therefore, as 2- Butoxyethyl methacrylate (EC 236-885-7) was insoluble in water, concentrations are expressed as nominal LR’s.

Description of key information

The 96 hour LC50 value of 2-Butoxyethyl methacrylate (EC 236-885-7) to Zebra fish was estimated to be 4.592mg/l LR (determined by Trimmed Spearman-Karber, trim = 42.9%). The 0 and 96hr NOEC and LOEC were determined by direct observation to be 3 and 5mg/l respectively. The lowest concentration giving 100% mortality of Zebra fish was >17.45mg/l LR. 

No analytical confirmation of the test substance concentrations was performed, therefore, as 2- Butoxyethyl methacrylate (EC 236-885-7) was insoluble in water, concentrations are expressed as nominal LR’s.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

4.592 mg/L