Isobutyric acid, monoester with 2,2,4-trimethylpentane-1,3-diol

Short-term toxicity to fish

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:

1995

Report date:

1995

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Isobutyric acid, monoester with 2,2,4-trimethylpentane-1,3-diol

EC Number:

246-771-9

EC Name:

Isobutyric acid, monoester with 2,2,4-trimethylpentane-1,3-diol

Cas Number:

25265-77-4

Molecular formula:

C12H24O3

IUPAC Name:

3-hydroxy-2,2,4-trimethylpentyl 2-methylpropanoate

Constituent 2

Reference substance name:

3-hydroxy-2,2,4-trimethylpentyl isobutyrate

EC Number:

201-049-2

EC Name:

3-hydroxy-2,2,4-trimethylpentyl isobutyrate

Cas Number:

77-68-9

Molecular formula:

C12H24O3

IUPAC Name:

3-hydoxy-2,2,4-trimethylpentyl isobutyrate

Details on test material:

CC(C)C(=O)OCC(C)(C)C(O)C(C)C
CC(C)C(=O)OC(C(C)(C))C(C)(C)CO

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 10.0, 15.0,30.0, 55.0, and 100.0 mg/L nominal
- Sampling method: Aliquots ofthe exposure solutions were submitted for concentration determinations at times 0, 48 hours (55.0 mg/L replicate B only) and 96 hours (with the exception of solutions containing nominally 100.0 mg/L). The exposure solutions containing nominally 100.0 mg/L (replicates A and B) were submitted at time 0 only as 100% mortality was observed among the test organisms at the 6-hour observation period. The exposure solution containing nominally 55.0 mg/L (replicate B only) was submitted at 48 hours as 100% mortality was observed among the test organisms within this replicate after 48 hours of exposure.

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: All exposure solutions (nominally 10.0, 15.0,30.0, 55.0, and 100.0 mg/L) were prepared by the addition of appropriate amounts of the test article to the test vessels. Each vessel (including control vessels) contained 20 L of diluent water. The test article solutions in each exposure vessel were vigorously stirred with a hand-held mixer. All exposure solutions for the test were prepared in replicates of two.

Test organisms

Test organisms (species):

Pimephales promelas

Details on test organisms:

Juvenile fathead minnows used in the test were obtained from the Eco-Chem Testing Group Breeding Facilities, Corporate Health and Environment Laboratories, Eastman Kodak Company, Rochester, New York 14652-6278. The fathead minnows were hatched within the laboratory on June 12, 1994 and designated as Lot No.: HAEL 061294. The organisms were approximately 50 days old at the start of testing. 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 anyone set oftest organisms at a time. Biological loading within test vessels was kept below 1.0 g wet weight per liter of test solution. The average wet weight for two of the twelve sets of minnows (10 minnows/set) was determined at the start ofthe test. These fathead minnows were subsequently sacrificed and a mean length determined. The mean length of replicate 1 minnows was 2.35 cm (the
range was 2.1 cm to 2.6 cm). The mean length of replicate 2 minnows was 2.25 cm (the range was 2.0 cm to 2.7 cm). The average wet weights of the minnows were 0.13 g for both replicates.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Test conditions

Hardness:

120 mg/L

Test temperature:

20 + or - 2C

pH:

7.8 - 8.2

Dissolved oxygen:

7.3 - 9.2 mg/L

Nominal and measured concentrations:

Nominal Mean Measured (mg/L)
10 11.1
15 15.6
30 28.5
55 50.7
100 97.1

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: seamless Pyrex glass 30.5-cm cuboidal chromatography jars containing 20L of solution
- Aeration: no
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2
- Biomass loading rate: <1.0 g wet weight per liter of test solution


TEST MEDIUM / WATER PARAMETERS
The water used in this test was pumped from Lake Ontario by the Kodak Park Lake Station Water Treatment Facility into a large underground storage reservoir located near the Environmental Sciences Section testing facility (Building 320, Kodak Park). This water subsequently was pumped into the laboratory where it passed through 3-micron (pore size) polypropylene filter tubes, next through a series of powdered, activated carbon filter tubes, and finally through another set of 3-micron polypropylene filter tubes. The filtered water stream next received 150 ppb ofNa2S203 via a chemical injection system. This treatment further reduced trace levels of residual chlorine. The filtered-treated water was subsequently tempered to 20 ± 2°C by passage through a heat-exchange unit. This filtered-treated tempered water supply was distributed throughout the testing facility through stainless steel and PVC piping. Upon reaching the laboratory, the filtered-treated-tempered water cascaded through a column degassing unit into an open, aeration basin for seasoning prior to use. Representative values for the hardness and total alkalinity (both as CaC03) for the study period were 120 mg/L and 95 mg/L, respectively.


OTHER TEST CONDITIONS
- Photoperiod:The light/dark cycle of the photoperiod was 16 hours on/8 hours offwith a 20-minute transition period.



EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Observations for mortality and signs of stress were made during this test at 0, 6, 24, 48, 72, and 96 hours.

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

33 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: effect conc. is average of replicates A and B (31 and 35 mg/L)

Effect concentrations 2

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

16 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Replicate A

Effect concentrations 3

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

26 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Replicate B

Details on results:

Nonlinear interpolation was used to calculate the 72 and 96-hour LC50 values for replicates A and B. The 24-, 48-, 72-, and 96-hour LC50 values for Pimephales promelas were calculated to be 40, 36, 32, and 31 mg/L, respectively, for replicate series A. The 24-, 48-, 72-, and 96-hour
LC50 values for replicate series B were calculated to be 41,38,38, and 35 mg/L, respectively. The 24-, 48-, 72-, and 96-hour No-Observed-Effect Concentration (NOEC) values for fathead minnows were determined to be 16 mg/L and 26 mg/L for replicate series A and B, respectively.

Reported statistics and error estimates:

A computer program developed by C.E. Stephan and ASTM was used to compute point and interval (i.e., confidence interval) estimates of the LC50 values for this test. The program required the following data: the concentration of the test substance (measured); the number of organisms exposed; and the number of organisms that died. Data for the control vessels were not entered as the program does not have the capability of adjusting for control mortality. Nonlinear interpolation was used to calculate the 96-hour LC50 values for replicates A and B.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Well conducted guideline study conducted under GLP resulting in LC50 and NOEC endpoint values.

Executive summary:

The acute toxicity of TEXANOL® Ester-Alcohol to the fathead minnow (Pimephales promelas) was determined in a 96-hour, static, aquatic effects test. The exposure solutions (nominally 10.0, 15.0,30.0, 55.0, and 100.0 mg/L) were prepared by the direct addition of appropriate amounts of the test article to the test vessels. With the exceptions of 100.0 mg/L (nominal) replicates A and B, and 55.0 mg/L (nominal) replicate B, exposure concentrations used throughout this report, and in all endpoint calculations were based on the analyzed mean values of the test article exposure solutions at times 0 and 96 hours. Exposure concentrations used throughout this report, and in all endpoint calculations for nominal concentrations containing 100.0 mg/L were based on the analyzed test article exposure solutions at time 0. The exposure concentration used throughout this report, and in all endpoint calculations for the nominal concentration containing 55.0 mg/L replicate B, was based on the analyzed mean value of the test article exposure solution at times 0 and 48 hours. Analyzed values were determined by gas chromatography. Replicate series minnow mortality results were not pooled for input into the LC50 program. The 24-, 48-, 72-, and 96-hour LC50 values for Pimephales promelas were calculated to be 40, 36, 32, and 31 mg/L, respectively, for replicate series A. The 24-, 48-, 72-, and 96-hour LC50 values for replicate series B were calculated to be 41,38,38, and 35 mg/L, respectively. The 24-, 48-, 72-, and 96-hour No-Observed-Effect Concentration (NOEC) values for fathead minnows were determined to be 16 mg/L and 26 mg/L for replicate series A and B, respectively. The minnows in the diluent water controls exhibited normal behavior and appearance throughout the test.