Sodium acrylate

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:

weight of evidence

Study period:

10 Mar 1989 - 14 Mar 1989

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

GLP guideline study with analytical monitoring

Qualifier:

according to guideline

Guideline:

EPA OTS 797.1400 (Fish Acute Toxicity Test)

GLP compliance:

yes

Analytical monitoring:

yes

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Stock solutions were prepared in deionized water to a concentration of 38000 mg/L.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: Rainbow trout
- Source: Mt. Lassen Trout Farms in Red Bluff, California, USA
- Length at study end (mean, SD): 43 ± 3 mm
- Weight at study initiation (mean, SD): 1.2 ± 0.27 g

HOUSING
- Conditions: fish were reared and maintained at ABC Laboratories in well water
- Feeding during housing:
- Food type: newly hatched brine shrimp or commercially fish food
- Frequency: daily
- Photoperiod: 16 hours daylight

ACCLIMATION
- Acclimation period: 28 hours
- Acclimation conditions: same as test
- Type of food: none

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

38 - 42 mg/L as CaCO3

Test temperature:

11 - 13 °C

pH:

4.6 - 7.9

Dissolved oxygen:

8.3 - 9.1 mg/L

Nominal and measured concentrations:

Nominal test concentrations: control, 6.5, 13, 25, 50, 100 mg/L
Mean measured concentrations: < 0.1, 6.3, 11, 23, 45, 90 mg/L

Details on test conditions:

TEST SYSTEM
- Type of flow-through: proportional diluter
- Renewal rate of test solution (frequency/flow rate): 10 times per hour, 120 L per day (8 tank volumes per day)
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: soft blended water (mixture of reverse osmosis and well water with a final hardness (as CaCO3) of ca. 40 - 48 mg/L
- Alkalinity: 53 - 54 mg/L as CaCO3
- Conductivity: 120 µMhos/cm
- Intervals of water quality measurement: Temperature, dissolved oxygen, pH in all test solutions after 0, 48, 96 hours of testing

OTHER TEST CONDITIONS
-Photoperiod: 16 hours
- Frequency: daylight

EFFECT PARAMETERS MEASURED: mortality and sublethal effects after 24, 48, 72, 96 hours

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2
- Range finding study: yes
- Test concentrations: 1, 10, 100 mg/L
- Results used to determine the conditions for the definitive study: 100 mg/L test substance = 100% mortality; 1 and 10 mg/L showed no effects

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

27 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95 % CL 21 - 33 mg/L

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

6.3 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

other: mortality, behavioral/sublethal effects

Details on results:

- LC50 after:
- 24 hours: > 45 mg/L
- 48 hours: 54 mg/L
- 72 hours: 34 mg/L

- Behavioural abnormalities: Erratic swimming , loss of equilibrium, quiescence, on bottom orientation

Sublethal observations / clinical signs:

		24 h		48 h		72 h		96 h
Meas. Test Conc. [mg/L]	No. placed in test	Cum. Mort.	Observations	Cum. Mort.	Observations	Cum. Mort.	Observations	Cum. Mort.	Observations
0	20	0	20 N	0	20 N	0	20 N	0	20 N
6.3	20	0	20 N	0	20 N	0	20 N	0	20 N
11	20	0	20 N	0	20 N	0*	17 N, 2 ES	0*	19 N
23	20	0	20 N	3	17 N	9	8 N, 3 ES	12	3 N, 5 ES
45	20	0	20 N	2	15 N, 2 ES	8	6 N, 6 ES	14	5 ES, 1 N
90	20	10	9 LOE/OB/Q 1 ES	20	---	20	---	20	---

Key to observations:
N: normal
LOE: loss of equilibrium
OB: on bottom orientation
Q: quiescence
ES: erratic swimming
* one individual lost

Validity criteria fulfilled:

yes

Description of key information

Acute harmful to fish. Based on data for the structural analogue acrylic acid, the LC50 (96 h) was 27 mg/L (BAMM, 1990)

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Effect concentration:

27 mg/L

Marine water fish

Marine water fish

Dose descriptor:

LC50

Effect concentration:

236 mg/L

Additional information

No experimental data on the test substance is available. Therefore, the evaluation of the endpoint short-term toxicity to fish is based on a weight of evidence approach using the data of the structural analogue acrylic acid (CAS 79-10-7) (for WoE information, see chapter 13.2).

Acrylic acid was tested in an acute toxicity test with Salmo gairdneri under flow-through conditions. Biological and chemical procedures followed the U.S. EPA-TSCA, 40 CFR, Part 797 Guideline 797.1400. Based on mean measured concentrations, the 96-hour LC50 was determined to be 27 mg/L (BAMM. 1990). Reported behavioral effects were: loss of equilibrium, on bottom orientation, quiescence and erratic swimming.

As supporting study, an acute fish test according to the 92/69/EEC part C1 with Danio rerio using a semi-static test design is available. Analytical concentration control by spectrophotometrical measurements revealed a recovery rate of >80 %. Therefore, effect values were based on nominal concentrations. The 96-hour LC50 was determined to be approx. 222 mg/L.

In a saltwater study conducted using the sheepshead minnow (BAMM, 1995), the 96-hour LC50 was estimated to be 236 mg/L. This study was conducted according to OECD Guideline 203 using a flow-through test design. The LC50 value was based on analytically determined concentrations. Analytical recovery was between 90 and 110 % of nominal concentrations. Mortality occurred only in the highest concentration of 297 mg/L. Clinical signs and symptoms observed were: lying on bottom, lethargy, surfacing, loss of equilibrium. The NOEC was determined to be 187 mg/L. Even though being a OECD-TG-study conducted in compliance with GLP regulations, this study is only valid with restrictions since during a seven-hour-period a malfunction in the diluter occurred that caused test substance concentrations to rise up to 200 % of nominal. The LC50 for Salmo gairdneri is with 27 mg/L about ten times lower. By choosing this value as most sensitive value for NaA a worst-case assumption is made.

In conclusion, based on the results of the most sensitive species testing acrylic acid, sodium acrylate is acute harmful to fish.