Registration Dossier

Administrative data

Endpoint:
short-term toxicity to fish
Type of information:
other: SIDS
Adequacy of study:
other information
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
data from handbook or collection of data

Data source

Referenceopen allclose all

Reference Type:
publication
Title:
SIDS for L-Glutamic acid
Author:
OECD
Year:
2013
Report Date:
2013
Reference Type:
study report
Title:
Unnamed
Year:
2009

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 203 (Fish, Acute Toxicity Test)
GLP compliance:
yes (incl. certificate)

Test material

Specific details on test material used for the study:
1. Name : L-glutamic acid
2. Supplier : Sigma-Aldrich Inc.
3. Purity : >=99.5 %
4. Appearance : White powder
5. Storage condition : Room temperature

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
1. Analysis of the test substance in the test solution: At initial exposure (0 hour) and at the end of exposure (after 96 hours), the samples were taken from mid-layer of 100 mg/L test solutions and centrifuged at 3000 rpm for 5 minutes. Duplicate samples from the top layer of each batch of test solutions diluted within the concentration range of calibration samples and analyzed. Also, duplicate samples from mid-layer of control group were centrifuged at 3000 rpm for 5 minutes and analyzed.

Test solutions

Details on test solutions:
1. Culturing and dilution water: Public tap water was filtered and irradiated by ultraviolet light and used as maintenance and dilution water.
2. Preparation of test solutions: The request amounts (active ingredient: 0.998) of the test substance were measured using an electronic balance. For preparation of stock and test solutions, the required amounts of the test substance were added to test chamber filled with dilution water. For the range finding study, a stock solution of 100 mg/L of the test substance was prepared using dilution water. This stock solution was diluted to concentrations of 10 and 1 mg/L of the test substance with dilution water. In definitive study, 100 mg/L test solution of the test substance was prepared. Each of 3 L test solution per test chamber was prepared, and the dilution water was used for the control group.

Test organisms

Test organisms (species):
Oryzias latipes
Details on test organisms:
1. Name: Oryzias latipes
2. Length: 2.38 cm (S.D. = 0.11 cm)
3. Body weight: 0.12 g (S.D. = 0.02g)
4. Source: National Institute of Environmental Research (Environmental Research Complex, Kyungseo-dong, Seo-gu, Incheon, Korea) on May 14, 2007.
5. Breeding method: Upon receipt, suitable male and female fish, at a ratio of 3 to 2 respectively, without any visible abnormalities and of similar length were selected and placed in a 50 L glass breeding chamber containing maintenance water. Approximately 50 fish (±10%) were bred. Eggs were harvested from the breeding chambers and placed in hatching chambers. After hatching, the fry were placed in a breeding chamber at 23±2°C and bred. Approximately 30% of the holding water is exchanged once a week. The holding room was artificially illuminated; 16 hours light, 8hours dark. Fish were fed Brine Shrimp (Ocean Star International, Inc., U.S.A.) in the morning and Top Meal (Jaeilfeed Co., Korea) in the afternoon, approximately 3% of their body weight daily, except on Sunday when they were fasted.
6. Acclimation: Prior to initiation, fish without any visible abnormalities and of similar length were selected and acclimated for 10 days in maintenance water. During the acclimation period, the water temperature and dissolved oxygen concentration in maintenance water were maintained at 22.1–23.8°C and 86.4–96.1%, respectively. The room was artificially illuminated with 16 hours of light and 8 hours of dark. The fish were fed Brine Shrimp eggs (Ocean Star International, Inc., U.S.A.) in the morning and Top meal (Jaeilfeed Co., Korea) in the afternoon, at an amount of approximately 3% of their body weight, once daily except on Sunday when they were fasted. Mortalities were observed from 48 hours after initiation of acclimation. During the seven days prior to exposure, mortalities of a batch of fish were less than 5% of populations, so a batch of fish was used.
7. Food supply: No food during the 24 hours period immediately prior to exposure.

Study design

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

Test conditions

Hardness:
61 mg/L as CaCO3
Test temperature:
23.1-23.8 °C
pH:
7.33-7.53
Dissolved oxygen:
7.09-7.64
Nominal and measured concentrations:
Nominal concentrations : control, 100 mg/L
Mean measured concentrations : N.D., 99.47 mg/L
Details on test conditions:
10 fish were placed in each chamber for 96 hours. Temperature and oxygen levels were maintained. The room was artificially illuminated with fluorescent lighting; 16 hour light, 8 hour dark cycle. Fish were not fed 24 hours prior to exposure. One replicate was used for each dosed group and control group.
Reference substance (positive control):
yes
Remarks:
Positive control studies using Copper (II) Sulfate (Wako Pure Chemical Industries, Ltd.) were conducted in Oryzias latipes for 96 hours and determined for LC50 under the same conditions of this study.

Results and discussion

Effect concentrationsopen allclose all
Key result
Duration:
96 h
Dose descriptor:
LC50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mortality
Key result
Duration:
96 h
Dose descriptor:
LC50
Effect conc.:
> 99.47 mg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
test mat.
Basis for effect:
mortality
Details on results:
1. Cumulative number of dead fish and general symptoms (Tables 1 and 2) During the exposure period, all the fish in the control group and the dosed group at 100 mg/L nominal concentration were normal without deaths or abnormal signs.
2. Length & weight of control fish at termination At the end of the test, total length and weight of the control fish were 2.38±0.11 cm and 0.12±0.02 g (mean±SD), respectively.
3. Water temperature, dissolved oxygen concentration and pH During the exposure period, the water temperature, dissolved oxygen concentration, and pH of test solution were 23.1–23.8°C, 7.09–7.64 mg/L (converted at air saturation value: 84.5–91.1%) and 7.33–7.53, respectively. These were within the range permitted for the study.
4. Observation of test solutions The test solutions in the control group were observed for transparency prior to exposure initiation and during the exposure period. The test solutions in the 100 mg/L dosed group were observed for transparency prior to exposure initiation and 24, 48 hours after exposure, while it was shown turbidity at 72 and 96 hours after exposure.
5. LC50 During the exposure period, the mortality was less than 50% (actual measurement: 0%) in the highest concentration dosed group, so the LC50 at 24, 48, 72, and 96 hours was determined as >100 mg/L, respectively.
Results with reference substance (positive control):
As a result, the LC50 at 96 hours after exposure was 0.31 mg/L, and it was within the historical control range (mean±2 SD: 0.24–0.48 mg/L).

Applicant's summary and conclusion

Validity criteria fulfilled:
not specified
Conclusions:
According to the range finding study, the definitive study was conducted for the control group and the 100 mg/L dosed group. In conclusion, the LC50 at 24, 48, 72, and 96 hours that was obtained under the test conditions with the test substance, L-glutamic acid (CAS No.: 56-86-0), was determined as >100 mg/L (nominal) (measured : 99.47 mg/L), respectively.
Executive summary:

This study was designed to assess the acute toxicity of the test substance, L-glutamic acid (CAS No.: 56-86-0), usingOryzias latipes, during a 96 hour exposure period and to determine the LC50 for the mortality of fish. The nominal concentration was set at 100 mg/L, and the control group was prepared for this study. The concentration of the test substance during the exposure period was within (+/-) 20% of the nominal concentrations. Therefore, all test results were determined as the nominal concentrations. In the control group, the concentration of the test substance was not detected. In conclusion, the LC50 at 24, 48, 72, and 96 hours that was obtained under the test conditions with the test substance, L-glutamic acid, was determined as >100 mg/L (nominal) (measured: 99.47 mg/L), respectively.