2-butenoic anhydride

Short-term toxicity to fish

Administrative data

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1996-02-29 to 1996-03-04

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1997

Report date:

1997

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

trans-crotonic acid

EC Number:

203-533-9

EC Name:

trans-crotonic acid

Cas Number:

107-93-7

Molecular formula:

C4H6O2

IUPAC Name:

(E)-2-Butenoic acid

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 5014045

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: One sample of control, high, middle and low treatment level
- Sampling method: Each exposure solution sample was collected from the approximate midpoint of the test vessel by volumetric pipet.
- Sampling invervals: at 0 hours (test initiation) and at 96 hours (test termination)

Test solutions

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method:
Two 50-mL Glenco® gas tight syringes, in conjunction with a Sage syringe pump, were each calibrated to deliver 0.025 mL per minute (for a total of 0.050 mL/minute) of the 100 mg A.I./mL stock solution into the dilutees primary chemical mixing chamber which also received 0.10 L of dilution water per minute. The solution contained within the mixing chamber had a nominal concentration which was equivalent to that of the highest nominal test concentration (50 mg A.l./L) and was proportionally diluted (50%) to produce the remaining nominal test concentrations. Based on the actual flow-rates of the test system's pumps, the remaining nominal concentrations were 23, 9.9, 3.8 and 1.5 mg A.l./L.


- Chemical name of vehicle :
Methanol was also used as co-solvent in concentrations of 0.50 mL/L.

- Concentration of vehicle in test medium (preparation day: -1):
100 mg A.I./mL stock solution: 50.0 g test substance with methanol to volume in a 500-mL volumetric flask.
0.72 mL/mL solvent stock solution: diluting 180 mL of methanol with distilled water to a volume of 250 mL in a volumetric flask.

- Evidence of undissolved material:
The saturated solution contained within the mixing chamber as well as all other solutions (i.e., chemical cell, splitter chamber, test vessel) were observed to be clear with no visible sign of undissolved test substance.

Test organisms

Test organisms (species):

Pimephales promelas

Details on test organisms:

TEST ORGANISM
- Common name: fathaed minnow
- Length at study initiation : mean total length of 38 mm (range 32 to 44 mm)
- Weight at study initiation : A representative sample (N = 30) of fish from the test population had a mean wet weight of 0.66 g (range 0.41 to 0.99 g)
- Food type: dry commercial pelleted food
- Amount: ad libitum
- Frequency: daily except during the 48 hours prior to testing

ACCLIMATION
- Acclimation period:minimum 14 days
- Acclimation conditions: 500 L fiberglass tank under a photoperiod of 16 hours light and 8 hours darkness.

- Health/mortality:No mortality was observed among the test fish population during the 48-hour period prior to testing

Study design

Test type:

flow-through

Limit test:

no

Total exposure duration:

96 h

Test conditions

Hardness:

36-40 mg/L CaCO3

Test temperature:

21-22°C

pH:

5.0-7.1

Dissolved oxygen:

6.0-10.0 mg/L

Nominal and measured concentrations:

Nominal concentrations: 1.5, 3.8, 9.9, 23 and 50 mg A.l./L
Exposure concentrations: 0.70, 2.6, 8.6, 22 and 46 mg A.l./L.

Details on test conditions:

TEST SYSTEM
- Test vessel:7
- Type: closed
- Aeration: During holding and prior to use, the dilution water was continuously aerated
- No. of vessels per concentration (replicates): 5
- No. of vessels per control (dilution water control): 1
- No. of vessels per vehicle control (replicates): 1


TEST MEDIUM / WATER PARAMETERS

- Total organic carbon: 0.66 and 0.44 mg/L
- Metals: no toxic concentration
- Pesticides:no toxic concentration
- Alkalinity: 29-39 mg/L
- Ca/mg ratio:20-23 mg/L (CaCO3)


OTHER TEST CONDITIONS
- Photoperiod: 16 hours light and 8 hours darkness
- Light intensity: 40 to 60 footcandles

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

31 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Effect concentrations 2

Key result

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

22 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

Following 72 hours of exposure, 100% mortality was observed among fish exposed to the highest treatment level tested, 46 mg A.l./L. No mortality or sublethal effects were observed among fathead minnow exposed to any of the remaining treatment levels tested (0.70 to 22 mg A.l./L).

Applicant's summary and conclusion

Conclusions:

Under the conditions of the present acute toxicity test to fish with Crotonic acid the LC50 and the NOEC after an exposure period of 96 hours was determinded to be 31 mg/L and 22 mg/L, respectively.