Ethyl acrylate

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

02 Apr 1989 - 06 Apr 1989 (Experimental dates)

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study conducted in compliance with GLP regulations

Qualifier:

according to guideline

Guideline:

EPA OTS 797.1400 (Fish Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

- Concentrations: The measured concentrations of EA in test water were determined at 0 and 96 hours of the test. All concentrations and the control were sampled and analyzed.
- Sampling method: At each sampling period, 50 mL aliquots of test water were collected from replicates A and B of each test solution and analyzed individually.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Diluter stock solutions of EA were prepared in deionized water to a concentration of 3800 mg/L. The stock injector volume was adjusted to deliver 3.5 mL of diluter stock to the 1.9 L in the mixing cell and to the 0.95 L in the solvent control cell of the diluter system. The mixing cell was used by the diluter to prepare the 7.0, 3.5, 1.8, 0.88, and 0.44 mg/L solutions while the solvent control cell was used to prepare the 14 mg/L test solution.
- Controls: dilution water control
- Evidence of undissolved material (e.g. precipitate, surface film, etc): no

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: Rainbow trout
- Lot.: # 5588
- Source: Mt. Lassen Trout Farms, Red Bluff, California
- Length at study initiation (length definition, mean, range and SD): 42 ± 4.3 mm (control)
- Weight at study initiation (mean and range, SD): 1.2 ± 0.37 g (control)
- Feeding during test: no feeding


ACCLIMATION
- Acclimation period: 48 hrs before study initiation
- Acclimation conditions: same as test
- Type and amount of food: during acclimation no feeding
- Health during acclimation (any mortality observed): no mortality

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

none

Hardness:

approx. 44 mg/L (as CaCO3)

Test temperature:

11 - 12 °C

pH:

7.7 - 7.9

Dissolved oxygen:

8.2 - 8.9 mg/L

Salinity:

-

Nominal and measured concentrations:

Nominal test concentrations: 0.44, 0.88, 1.8, 3.5, 7.0 and 14 mg/L
Mean measured concentrations: 0.34, 0.78, 1.7, 3.3, 6.5 and 13 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: 15 L
- Aeration: no data
- Type of flow-through: Proportional diluter system as described by Mount and Brungs (Water Res. 1: 21-29, 1967) and a Hamilton Model 420 syringe dispenser were used for the intermittent introduction of EA test solutions and/or diluent water into each test chamber. The diluter delivered 0.5 L of test solution or control water to each replicate test chamber at an average rate of 8.1 times per hour over the course of the study.
- Renewal rate of test solution (frequency/flow rate): flow rate 97.2 L/day equivalent to 6.5 tank volumes/day
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2 (dilution water control)
- Biomass loading rate: 0.12 g/L/day (control)


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: soft blended water (mixture of reverse osmosis and well water)
- Total organic carbon: < 1 ppm
- Particulate matter: 0.4 mg/L
- Pesticides: < 0.5 ppb
- Alkalinity: 54 - 57 mg/L
- Conductivity: 106 - 120 µMhos/cm



OTHER TEST CONDITIONS
- Adjustment of pH: 7.7 - 7.9
- Photoperiod: 16 hrs light / 8 hrs dark



EFFECT PARAMETERS MEASURED (with observation intervals if applicable): Temperature, dissolved oxygen and pH were measured in all test solutions at 0, 72, and 96 hours of testing.


TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2
- Range finding study
A preliminary static 96-hour range-finding test was conducted to determine a concentration range of EA to be used in the definitive test.
- Test concentrations: 0.99, 10, and 100 mg/L
- Results used to determine the conditions for the definitive study: Complete mortality ocurred at 10 and 100 mg/L, while some abnormal effects were noted at 0.99 mg/L.

Reference substance (positive control):

not specified

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

0.78 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

behaviour

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

4.6 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 3.3 - 6.5 mg/L

Details on results:

- Behavioural abnormalities: Behavioral/sublethal effects noted during the study included on-bottom orientation, surfacing, dark discoloratin, quiescence and loss of eqilibrium.
- Mortality of control: no
- Other adverse effects control: no
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: none

Sublethal observations / clinical signs:

Prior to the initiation of the rainbow trout toxicity test, a method validation was conducted to determine the recovery of EA in test water. Fortification concentrations ranged from 0.253 to 101 mg/L and yielded an average recovery of 100 ± 8.9 %.

From the data collected during this study, a 96-hour LC50 with 95% confidence limits was calculated to be 4.6 mg/L
(3.3 to 6.5 mg/L) based on the mean measured concentrations of Ethyl Acrylate. The slope of the 96-hour dose-response
line was 16. Mortality occurred in the 6.5 and 13 mg/L test concentrations. Sublethal/behavioral responses (e.g.
on-bottom orientation, dark discoloration, surfacing, quiescence and loss of equilibrium) were noted among the
fish in the 1.7, 3.3, 6.5 and 13 mg/L test levels. The 96-hour no-effect concentration of ethyl acrylate to rainbow
trout was 0.78 mg/L based on a lack of mortality and sublethal responses at this concentration.

Cumulative mortalities:

Meas. test conc. [mg/L]	No. placed in test	24 h	48 h	72 h	96 h
Control	20	0	0	0	0
0.34	20	0	0	0	0
0.78	20	0	0	0	0
1.7	20	0	0	0	0
3.3	20	0	0	0	0
6.5	20	0	1	20	20
13	20	0	20	20	20

Behavioral observations:

Meas. test conc. [mg/L]	No. placed in test	24 h	48 h	72 h	96 h
Control	20	N	N	N	N
0.34	20	N	N	N	N
0.78	20	N	N	N	N
1.7	20	N	N	N	16N; 3Q; 1Q/OB
3.3	20	19N; 1OB	11N; 8 ; 1DK	12N; 7OB; 1SUR	8N; 8OB; 4SUR
6.5	20	8N; 7OB; 2SUR; 3Q	1N; 1LOE; 7OB; 10SUR	--	--
13	20	1N; 5OB; 14 SUR	--	--	--

N = normal

OB = on-bottom orientation

SUR = surfacing

Q = quiescence

LOE = loss of equilibrium

DK = dark discoloration

Validity criteria fulfilled:

yes

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

16 Nov 1994 - 26 Sep 1995

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP-Guideline study with acceptable restrictions.

Qualifier:

according to guideline

Guideline:

EPA OTS 797.1400 (Fish Acute Toxicity Test)

Principles of method if other than guideline:

The study was conducted according to the procedures outlined in Title 40 of Code of Federal Regulations, Part 797.1400 and OECD Guideline 203, Fish Acute Toxicity Test and ASTM Standard E 729-88, Standard Guide for Conducting Acute Toxicity Tests with Fishes, Macroinvertebrates and Amphibians.
GLP study with the following exceptions: 
1) Test substance characterization provided by the Sponsor (BAMM) was not conducted in compliance with GLP; 
2) Stability of the test substance under storage conditions at the test site was not conducted in compliance with GLP; 
3) Documentation for the preparation of two analytical standards could not be found.

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

Mean measured test concentrations were determined from samples of test water collected from each test chamber at the beginning of the test and at test termination.
- Concentrations: control, 1.3, 2.2, 3.6, 6.0 and 10 mg/L.
- Sample storage conditions before analysis: 4 °C

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: One stock solution was prepared for each of the five concentrations tested. Ethyl acrylate was dissolved in reverse osmosis water at concentrations of 0.648, 1.08, 1.80, 3.00 and 5.00 mg ethyl acrylate/mL. The stock solutions were inverted to mix. The five stocks were injected into the diluter mixing chambers (at a rate of 250 μL/minute) where they were mixed with saltwater (at a rate of 125 mL/minute) to achieve the desired test concentrations. Stock concentrations and the resultant test concentrations were not adjusted for the purity of the active ingredient in the test substance (99.31 %).
- Differential loading: yes
- Controls: saltwater
- Evidence of undissolved material (e.g. precipitate, surface film, etc): no

Test organisms (species):

Cyprinodon variegatus

Details on test organisms:

TEST ORGANISM
- Common name: Sheepshead minnow
- Source: Wildlife International Ltd., Easton, Maryland
- Age at study initiation: juvenile
- Length at study end: mean 17 mm, range 15 - 20 mm (average standard length of 10 negative control fish measured at the end of the test)
- Weight at study initiation: mean 0.17 g, range 0.096 to 0.25 g (average standard weight of 10 negative control fish measured at the end of the test)
- Feeding during test: none


ACCLIMATION
- Acclimation period: 14 days prior to test
- Acclimation conditions: same as test (23.2 to 23.5°C, pH 7.8 to 7.9, salinity 20 to 22 parts per thousand, 6.4 to 7.8 mg oxygen/L)
- Health during acclimation (any mortality observed): no mortality

Test type:

flow-through

Water media type:

saltwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

no data

Test temperature:

21.8 - 22.1 °C

pH:

8.2 - 8.3

Dissolved oxygen:

6.1 - 6.9 mg/L

Salinity:

20 parts per thousand

Nominal and measured concentrations:

Nominal test concentrations: negative (saltwater) control, 1.3, 2.2, 3.6, 6.0 and 10 mg/L.
Mean measured concentrations: negative (saltwater) control, 0.62, 0.86, 1.6, 3.2 and 5.4 mg/L.

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: Teflon-lined, 25-L polyethylene aquaria filled with approximately 15 L of test water.
- Aeration: yes
- Type of flow-through: continuous-flow diluter
- Renewal rate of test solution (frequency/flow rate): The diluter was adjusted so that each test chamber received approximately six volume additions of test water every 24 hours.
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2
- Biomass loading rate: 0.019 g fish/L (total wet weight of fish per liter of test water that passed through the test chamber in 24 hours)
- Instantaneous loading: 0.12 g fish/L (of test water present in the test chambers at any given time)


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: natural seawater collected at Indian River, Inlet, Delaware, and diluted to a salinity of approximately 20 parts per thousand with well water. The freshly-collected seawater was passed through a sand filter to remove particles greater than approximately 25 μm, and pumped into a 37800-L storage tank. The filtered seawater then was diluted with freshwater from a well on the Wildlife International Ltd. site and aerated with spray nozzles. Prior to delivery to the diluter system, the water again was filtered to remove microorganisms and particles.
- Total organic carbon: 0.5 mg/L
- Particulate matter: 19800 mg/L
- Metals: < 60 µg/L
- Pesticides: < 3 µg/L
- Culture medium different from test medium: no


OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 h/8 h light/dark
- Light intensity: 463 - 481 lux at the surface of the water

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Observations of mortality and other clinical signs were made approximately 2, 24, 48, 72 and 96 hours after test initiation. Dissolved oxygen, pH and salinity measurements were made on water samples collected from each replicate test chamber at test initiation at approximately 48 hours and at test termination.

Reference substance (positive control):

not specified

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

0.62 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

behaviour

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

2 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 1.6 - 3.2 mg/L

Details on results:

- Behavioural abnormalities:  Lethargy, loss of  equilibrium, discoloration and erratic swimming were observed at 1.6 mg/L, and lethargy and discoloration were observed at 0.86 mg/L.
- Mortality of control: none
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: no
- Effect concentrations exceeding solubility of substance in test medium: no

- Analytical monitoring:
Test samples were analyzed by HPLC. Measured concentrations of EA in pre-test samples ranged from 45 to 62 % of nominal. Samples collected at test initiation ranged from 50 to 64 % of nominal. Samples collected on Day 4 ranged from 25 to 46 % of nominal.  Day 4 samples in the 2.2 and 3.6 mg/L groups were reanalysed. Mean measured concentrations throughout the  test were averaged and were used to calculate the LC50 value using binomial probability with nonlinear interpolation procedure. The low and variable recoveries of ethyl acrylate were thought to be due to the volatile nature of the test substance (vapor pressure 41 hPa at 20°C). The LC50 is therefore considered to be only an approximation.
After 96 hours, mortality was 0, 0, 15, 100 and 100 % at the 0.62, 0.86, 1.6, 3.2 and 5.4 mg/L concentrations, respectively.

Sublethal observations / clinical signs:

Mean meas. Conc. [mg/L]			2 h	24 h	48 h	72 h	96 h	Cum. mortality
	Rep.	No. exposed	No. dead	No. dead	No. dead	No. dead	No. dead
Control	A	10	0	0	0	0	0	0 %
	B	10	0	0	0	0	0
0.62	A	10	0	0	0	0	0	0 %
	B	10	0	0	0	0	0
0.86	A	10	0	0	0	0	0	0 %
	B	10	0	0	0	0	0
1.6	A	10	0	0	0	0	1	15 %
	B	10	0	0	0	1	2
3.2	A	10	0	1	7	10	10	100 %
	B	10	0	0	6	10	10
5.4	A	10	0	1	10	10	10	100 %
	B	10	0	1	10	10	10

Mean meas. Conc. [mg/L]	Rep.	No. exposed	2 h	24 h	48 h	72 h	96 h
			Effects	Effects	Effects	Effects	Effects
Control	A	10	10AN	10AN	10AN	10AN	10AN
	B	10	10AN	10AN	10AN	10AN	10AN
0.62	A	10	10AN	10AN	10AN	10AN	10AN
	B	10	10AN	10AN	10AN	10AN	10AN
0.86	A	10	10AN	10AN	10AN	10AN	9AN, 1D
	B	10	10AN	10AN	9AN, 1D	9AN, 1DAC	8AN, 1D, 1DC
1.6	A	10	10AN	10AN	10AN	4AN, 2C, 4D	2AN, 1ND, 1E, 3CD, 2ED
	B	10	10AN	10AN	8AN, 2D	4AN, 4CD, 1E	1AN, 5CD, 1AD, 1E
3.2	A	10	10AN	9AN	1C, 1D, 1ED	-	-
	B	10	10AN	10AN	1AN, 1ED, 2CD	-	-
5.4	A	10	10AN	5AN, 4D	-	-	-
	B	10	10AN	8AN, 1DE	-	-	-

AN: appears normal

D: Discoloration

E: Erratic swimming

C: Lethargic

A: Surfacing

N: Loss of equilibrium

Validity criteria fulfilled:

yes

Description of key information

Ethyl acrylate is acutely toxic for freshwater and marine fish.
LC50 (96 h, flow through) = 4.6 mg/L (measured) (Salmo gairdneri, EPA OTS 797.1400)
LC50 (96 h, flow through) = 2.0 mg/L (measured) (Cyprinodon variegatus, EPA OTS 797.1400)

As described in section 13.2 of IUCLID, testing information is consistent with six acrylic esters evaluated as a category.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

4.6 mg/L

Marine water fish

Marine water fish

Effect concentration:

2 mg/L

Additional information

In the key study for acute toxicity to fish (BAMM, 1990), the 96-hour LC50 for rainbow trout was 4.6 mg/L based on the mean measured concentrations. This study followed EPA OTS Guideline 797.1400 using a flow-through design. Nominal exposure concentrations ranged from 0.44 to 14 mg/L and mean measured concentrations (0 and 96 hrs) ranged from 0.34 to 13 mg/L. Mortality occurred in the two highest concentrations (6.5 and 13 mg/L, measured). The LC50 was determined based on analytical values.

In a saltwater study conducted in the sheepshead minnow (BAMM, 1995), the 96-hour LC50 was estimated to be 2 mg/L but poor analytical recovery suggested this value is only an approximation. This study was conducted according to EPA OTS Guideline 797.1400 using a flow-through design. Nominal test concentrations ranged from 1.3 to 10 mg/L, and mean measured concentrations from 0.62 to 5.4 mg/L. The LC50 value was based on analytically determined concentrations.

In addition, a robust data set of acute studies is available from the other members of the acrylic ester category (methyl, 2-ethylhexyl, n-butyl, isobutyl, and tert-butyl acrylate).