Registration Dossier

Administrative data

Endpoint:
short-term toxicity to fish
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Guideline study conducted under GLP

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1997
Report Date:
1997

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 203 (Fish, Acute Toxicity Test)
Deviations:
no
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
liquid: viscous
Details on test material:
- Name of test material (as cited in study report): Sucrose Acetate Isobutyrate or SAIB
- Physical state: Viscous amber liquid
- Lot/batch No.: 4002606

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
Temperature, dissolved oxygen, and pH were measured in each replicate of the control, solvent control, and substance exposure solutions at 0, 24, 48, and 96 hours. Concentration verification was conducted at time 0 and at test termination at 96 hours.

Test solutions

Vehicle:
yes
Details on test solutions:
The acute aquatic effects test was performed in seamless Pyrex glass 30.5-cm cuboidal chromatography jars, each containing 20 L of exposure solution. All exposure solutions (nominally 40 mg/L) were prepared by the addition of appropriate amounts of the test substance stock solution to the test vessels. The stock solution was prepared in a carrier solvent, N,N-dimethylformamide (DMF), as the test substance had negligible aqueous solubility. The replicate exposure solutions were prepared by the addition of the appropriate amount of the test substance stock solution to each test vessel containing dilution water. The concentration of the test substance exposure solution contained the carrier solvent at a concentration of no more than 0.1 mL/L. The stock solution was sonicated for approximately one hour and fifteen minutes prior to use. At test start, the exposure solution in each of the test vessels was vigorously stirred with a hand-held mixer prior to the addition of the organisms. All test solutions and controls for the test were prepared in replicates of two.

At time 0, the exposure solutions containing the test substance appeared clear with particulates on the solution surfaces and at the bottoms of the test vessels. From time 24 hours to test end, the solutions had a precipitate on the bottoms of the test vessels and slicks on the solution surfaces.

Test organisms

Test organisms (species):
Pimephales promelas
Details on test organisms:
Juvenile fathead minnows used in the test were obtained from Aquatic BioSystems, 1300 Blue Spruce Drive Suite C, Fort Collins, Colorado, and designated the Lot Number 082896ABS. The fathead minnows were hatched on 8/28/96- 9/11/96 and the date of receipt was 11/15/96. The organisms were approximately 138 days old at the start of testing, using the earlier hatch date of 8/28/96. All organisms for this test were acclimated to the diluent water prior to the test since the same filtered-treated-tempered water and filtered, compressed air used for all laboratory water/aeration processes during the test were supplied continuously to the stainless steel rearing tanks. All aquatic organism populations used in the laboratory were maintained in this water for at least two weeks before being used in the test. Juvenile fathead minnows, as uniform in size as possible, were removed from the holding tanks and transferred to collection vessels. Sequential randomization was accomplished by allocating to each vessel no more than 50% of any one set of test organisms at a time. The average wet weights for two additional sets of minnows (7 minnows/set) were determined at the start of the test to be 0.69 g for set #1 and 0.76 g for set #2. These fathead minnows were subsequently sacrificed and. a mean standard .length determined. The mean standard lengths for set # 1 and set #2 were 3 7.1 mm and 37.3 mm, respectively.

Study design

Test type:
static
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
96 h

Test conditions

Hardness:
124 mg/L as CaCO3
Test temperature:
19-20°C
pH:
7.7 - 8.5
Dissolved oxygen:
6.1 - 9.1 mg/L
Nominal and measured concentrations:
The limit test was designed to expose the organisms to a saturated solution of the poorly soluble substance. The test substance was introduced at a nominal concentration of 40 mg/L using a carrier solvent and stirred thoroughly. The measured concentrations at time 0 w ere 6.64 and 8.14 mg/L (replicate A and B solutions, respectively). The measured concentrations at 96 hours were less than the method detection limit of 0.9 mg/L. No test substance was detected in any of the control or solvent control solutions. The test substance concentrations, as determined by gas chromatography with flame ionization detection(GC/FID), were mathematically derived as the geometric mean of the analyzed sample concentration values of the test solutions at times 0 and 96 hours. The average of the geometric mean of the sample concentrations for the pooled replicates was determined to be 1.82 mg/L.
Details on test conditions:
The acute aquatic effects test was performed in seamless Pyrex glass 30.5-cm cuboidal chromatography jars, each containing 20 L of exposure solution. 2 replicates with 7 fish/replicate were used for the dilution water control, solvent control, and the test substance exposure solution. The light/dark cycle of the photoperiod was 16 hours on/8 hours off with a 30-minute transition period. Observations for mortality and signs of stress were made during this test at 0, 5, 24, 48, 76, and 96 hours.

Results and discussion

Effect concentrationsopen allclose all
Duration:
96 h
Dose descriptor:
NOELR
Effect conc.:
>= 40 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mortality
Duration:
96 h
Dose descriptor:
NOEC
Effect conc.:
>= 1.82 mg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
test mat.
Basis for effect:
mortality
Duration:
96 h
Dose descriptor:
EL50
Effect conc.:
> 40 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mortality
Duration:
96 h
Dose descriptor:
LC50
Effect conc.:
> 1.82 mg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
test mat.
Basis for effect:
mortality
Details on results:
No mortality was observed in the control, solvent control or the test substance exposure solution over the 96 hour exposure.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Executive summary:

The acute toxicity of the test substance to the fathead minnow (Pimephales promelas) was determined in a 96-hour, statie, aquatic effects Limit test. The test substance stock solution was prepared in the carrier solvent N,N-dimethylformamide, as the test substance had negligible aqueous solubility. The exposure solutions were prepared by direct addition of the test substance stock solution to the test vessels containing 20 L of dilution water to achieve a nominal concentration of 40 mg/L. The exposure solutions were vigorously stirred with a hand-held mixer prior to the addition of the organisms. Samples of the solutions containing the test substance and the control solutions were submitted for chemical analysis at test initiation (time 0) and test temination (96 hours). At time 0, the exposure solutions containing the test substance appeared clear with particulates on the solution surfaces and at the bottoms of the test vessels. From time 24 hours to test end, the solutions had a precipitate on the bottoms of the test vessels and slicks on the solution surfaces. Based upon these observations and the knowledge of the water solubility of the test substance (< 1 mg/L), it is apparent that the organisms were exposed to the test substance at and above the saturation limit. The test substance concentrations, as determined by gas chromatography with flame ionization detection (GC/FID), were mathematically derived as the geometric mean of the analyzed sample concentration values of the test solutions at times 0 and 96 hours. The average of the geometric mean of the sample concentrations for the pooled replicates was determined to be 1.82 mg/L. No mortality was observed in the control, solvent control, or test substance exposures. The results indicate that the test substance is not toxic at the limit of water solubility (saturation).