2-ethylhexanoic acid, compound with 2-aminoethanol (1:1)

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:

28/09/2009 - 05/02/2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

other: ISO 14669 (1999) Water Quality - Determination of acute lethal toxicity to marine copepods (Copepoda; Crustacea)

Deviations:

no

Remarks:

Determined from guideline criteria and observed values

Qualifier:

according to guideline

Guideline:

other: ISO 5667-16 (1998) Water Quality Sampling – Guidance on biotesting of samples

Deviations:

no

Remarks:

Determined from guideline criteria and observed values

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: Test substance added to seawater and stirred for 1 hour to dissolve.
- Final dilution of a dissolved solid, stock liquid or gel: A series of dilutions was made (100, 320, 1000, 3200, 10000 mg/L nominal concentration) from a prepared 10 000 mg/L (Nominal concentration) stock solution .
- Final preparation of a solid: Dissovled in seawater.

FORM AS APPLIED IN THE TEST (if different from that of starting material) Aqueous, in solution

Analytical monitoring:

no

Details on sampling:

- Concentrations: Nominal concentrations used for test substance were 100, 320, 1000, 3200, 10000 mg/L.
- Sampling method: Proportional mortality observations within a population

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Test substance was added directly to filtered and sterilised seawater, stirred for 1 hour.
- Controls: 4 mortality controls containing 0 ml/ L test material with 1 replicate each. 5 positive controls (3, 5 Dichlorophenol, reference substance) at 0.1, 0.32, 1.0, 1.8 and 3.2 mg/ L, with 2 replicates per concentration.
- Evidence of undissolved material (e.g. precipitate, surface film, etc.): No, substance stated as soluable.

Test organisms (species):

other aquatic crustacea: Acartia tonsa

Details on test organisms:

TEST ORGANISM
- Common name: Acartia tonsa; marine copepod
- Strain: CCAP 1077/5
- Source: Cultured and recieved from Dunstaffnage Marine Laboratory in 1995
- Age of parental stock (mean and range, SD): Not specified, test organims used were 17-25 days old at test initiation
- Feeding during test: Cultures were maintained on a mixed algal diet comprising of between 2 and 4 species
- Food type: Mixed algal diet

Test type:

static

Water media type:

saltwater

Limit test:

no

Total exposure duration:

48 h

Remarks on exposure duration:

Two time points measured, 24 hours and 48 hours.

Test temperature:

20 (+-2)°C

pH:

8.07 - 8.25

Dissolved oxygen:

91 - 98 %

Salinity:

35‰

Nominal and measured concentrations:

For the definitive test, the test substance preparations had nominal concentrations of 100, 320, 1000, 3200 and 10 000 mg/ L and an actual norminal concentration of 100, 320, 1000, 3200 and 10 004 mg/L, respectively.

Details on test conditions:

TEST SYSTEM
- Test vessel: borosilicate glass crystallising dishes
- Type (delete if not applicable): closed
- Material, size, headspace, fill volume: 100 ml capacity
- Type of flow-through (e.g. peristaltic or proportional diluter): None
- Renewal rate of test solution (frequency/flow rate): None
- No. of organisms per vessel: Definitive test: Between 19 and 21, Control:Between 9 and 22
- No. of vessels per concentration (replicates): 2 replicates per test substance concentration
- No. of vessels per control (replicates): 1 replicate for 0 mg/ L of test substance, 2 replicates for 3,5 Dichlorophenol reference substance

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Natural seawater is supplied by pump from Scapa Flow, Orkney (UV sterilised, 0.2 µm filtered, 36±4 ‰ salinity)
- Alkalinity: pH 7.99
- Salinity: 35 ‰ salinity
- Culture medium different from test medium: Culture medium contained seawater filtered at 0.45 µm and contained a mixed algal diet.
- Intervals of water quality measurement: At 0 h tests were conduct for controls and definitive tests.

OTHER TEST CONDITIONS
- Adjustment of pH: Not needed as within range of standard

EFFECT PARAMETERS MEASURED : LC50 at 24 and 48 hours. LC90 and NOEC at 48 hours only

RANGE-FINDING STUDY
- Test concentrations: Concentrations tested were 1, 10, 100 and 1000. At 48 hours the LC50 was greated than 1000 mg/L
- Results used to determine the conditions for the definitive study: Yes.

Reference substance (positive control):

yes

Remarks:

3,5 Dichlorophenol

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

1 851.12 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Key result

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

903.17 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

48 h

Dose descriptor:

other: LC90

Effect conc.:

2 713.01 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

320 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

- Mortality of control: 0 - 10% mortatily in control
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: Measurements provided to demonstrate accuracy at stock concentration and serial dilutions
- Effect concentrations exceeding solubility of substance in test medium: No

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- Relevant effect levels: For 48 hour LC50 was 1.36 mg/L of reference substance
- Limit test: Not performed
- Dose-response test: 0.1, 0.32, 1, 1.8 and 3.2 mg/L reference substance (nominal concentration) tested.
- ECx: LC50, LC90 and NOEC

Validity criteria fulfilled:

yes

Conclusions:

2-Butyl butanoic acid compound with 2-aminoethanol has a 48 hour LC50 value of 903.17 mg/L for the organism Acartia tonsa when dissolved in solution (seawater).

Executive summary:

The study assesses the short-term toxicity of 2 -Butyl butanoic acid compound with 2 -aminoethanol to aquatic invertebrates. The study is performed in compliance with GLP and the testing guidelines followed were ISO 14669 (1999) Water Quality and ISO 5667 -16 (1998) - Water quality sampling. All validity criteria were complied with. The test organism used was Acarita tonsa and the test was performed using saltwater (seawater). A rangefinding test was initially performed to show that the 48 hour LC50 was greater than 1000 mg/L. The definitive test used a range of nominal concentrations of 100, 320, 1000, 3200 and 10 000 mg/L of test substance. This range was produced by dissolving the test material in seawater (maximum concentration) and then producing a series of serial dilutions. 4 mortality controls (0 mg/ L test substance) were included with 1 replicate each to show a proportional mortality response of 0 - 10%. 5 positive controls with the reference substance (3,5 Dichlorophenol) were included, each at a different concentration (0.1, 0.32, 1.0, 1.8 and 3.2 mg/L) to show a 48 hour LC50 of 1.36 mg/ L. The results of the definitive test showed that the test substance has an LC50 value of 1851.12 mg/L at 24 hours and 903.17 mg/L at 48 hours. Other results include the LC90 value at 48 hours of 2713.01 mg/L and NOEC at 48 hours of 320 mg/L.

Description of key information

The study assesses the short-term toxicity of 2 -Butyl butanoic acid compound with 2 -aminoethanol to aquatic invertebrates. The study is performed in compliance with GLP and the testing guidelines followed were ISO 14669 (1999) Water Quality and ISO 5667 -16 (1998) - Water quality sampling. All validity criteria were complied with. The test organism used was Acarita tonsa and the test was performed using saltwater (seawater). A rangefinding test was initially performed to show that the 48 hour LC50 was greater than 1000 mg/L. The definitive test used a range of nominal concentrations of 100, 320, 1000, 3200 and 10 000 mg/L of test substance. This range was produced by dissolving the test material in seawater (maximum concentration) and then producing a series of serial dilutions. 4 mortality controls (0 mg/ L test substance) were included with 1 replicate each to show a proportional mortality response of 0 - 10%. 5 positive controls with the reference substance (3,5 Dichlorophenol) were included, each at a different concentration (0.1, 0.32, 1.0, 1.8 and 3.2 mg/L) to show a 48 hour LC50 of 1.36 mg/ L. The results of the definitive test showed that the test substance has an LC50 value of 1851.12 mg/L at 24 hours and 903.17 mg/L at 48 hours. Other results include the LC90 value at 48 hours of 2713.01 mg/L and NOEC at 48 hours of 320 mg/L.

Key value for chemical safety assessment

Marine water invertebrates

Marine water invertebrates

Effect concentration:

903.17 mg/L