Registration Dossier

Ecotoxicological information

Short-term toxicity to fish

Currently viewing:

Administrative data

Link to relevant study record(s)

Reference
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: GLP study in compliance with international guidelines
Qualifier:
according to guideline
Guideline:
OECD Guideline 203 (Fish, Acute Toxicity Test)
Deviations:
no
Qualifier:
according to guideline
Guideline:
other: (3) OECD Guidance Document No.23 “Guidance Document on Aquatic Toxicity Testing of Difficult Substance and Mixtures” (September2000)
Deviations:
no
GLP compliance:
yes
Specific details on test material used for the study:
Details on properties of test surrogate or analogue material (migrated information):
not applicable
Analytical monitoring:
yes
Details on sampling:
After the test sample was added into the dilution water filled in Erlenmeyer flask with micro volumeter (Eppendorf Co., Ltd) to prepare test solution of 100 mgI as nominal concentration, the flask was immediately sealed with a plug not to produce head space. The solution was gently stirred by a magnetic stirrer for about 24 hours to produce a dispersed solution with suspended test item. After cease of stirring, the solution was settled for 1 hour and then test solution was prepared by taking out from the middle layer of the settled solution. The prepared test solution was immediately divided into each test vessel and covered with a glass lid not to produce head space.
Vehicle:
no
Details on test solutions:
No correction with purity was done for the preparation of the test concentration. The test sample was employed in terms of volume using the density [1.554 Wcm3 (25 °C)] for the preparation of test solution.
After the test sample was added into the dilution water filled in Erlenmeyer flask with micro volumeter (Eppendorf Co., Ltd) to prepare test solution of 100 mg/I as nominal concentration, the flask was immediately sealed with a plug not to produce head space. The solution was gently stirred by magnetic stirrer for about 24 hours to produce dispersed solution with suspended test item. After cease of stirring, the solution was settled for 1 hour and then test solution was prepared by taking out from the middle layer of the settled solution. The prepared test solution was immediately divided into each test vessel and covered with glass lid not to produce head space.
Test organisms (species):
Oryzias latipes
Details on test organisms:
Species: Medaka (Oryzias latipes)
Reason for selection of species: This species is recommended in the test guidelines.
Size: Total length 2.3 ±1.2 cm
Size of test organism was applied the regulated size set to test method.
Supplier: Kunime Laboratory, Chemicals Evaluation and Research Institute, Japan
3-2-7 M.iyanojin, Kurume-shi, Fulcuoka 839-0801, Japan
Acclimation: Medaka hatched out on December 11, 2006 were acclimated for 14 days by flow-through condition under the same water quality (dechlorinated tap water), temperature (24 ±1 °C), light and dark period (16-hour light / 8-hour dark) as test condition (on May 21 to June 4, 2007). The mortality was 0% during the 7 days before the start of the exposure. The test organism at the start of the exposure was 5-month-old fish. The test organisms were not treated with a medicament for external disinfection. The test organisms were fed the feed mixture for carp, and not fed for 24 hours before the start of the exposure. Dissolved oxygen concentration in breeding water during acclimation was kept not less than 80% of air saturation value. A 96-hour acute toxicity test of CuSO4*5H2O (Reagent chemical, Wako Pure Chemical Industries, Ltd.) to confirm reproducibility of the test system was carried out on May 21 to May 25, 2007 and the 96-hour LCD50 was 0.445 mg/L. This value was within the stipulated range (mean ± 2 S.D.: 0.124 to 0.978 mg/L) [mean ± S.D.: 0.551 ± 0.214 mg/L (n=38) to background data in this laboratory. All of the values shown above for the reference substance were converted into CuSO4 value.
Allocation to the test groups: Medaka were allocated at random to each test group.
Test type:
semi-static
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
96 h
Post exposure observation period:
not applicable
Hardness:
as CaCO3: 41.9 mg/L
Test temperature:
24 ±1 °C
pH:
7.9 at 22 °C
Dissolved oxygen:
The test was performed in the condition where dissolved oxygen concentration was at least 60% or more of the saturated concentration at the water temperature. Aeration was not used during the exposure.
Salinity:
no data
Nominal and measured concentrations:
Based on the results of the preliminary studies, it was expected that the test solution at around the solubility in dilution water would have no effect on the test organisms. Therefore, the definitive study was conducted as the limit test with suspended solution which was prepared by taking out from the middle layer of 24-hour mixed solution (nominal concentration: 100 mg/L). The results of the preliminary studies are shown in Additional data.
Details on test conditions:
Observation of test organisms
Mortality and visible abnormality were observed at 3, 24,48, 72 and 96 hours after the start of the exposure. A fish was considered dead if the observable motion (motion of mouth and opercula etc.) were not observed and touching of the caudal peduncle with glass rod produced no reaction.
Total length and body weight of test organism
The test organisms in the control group were used for measuring total length and body weight after the end of the exposure.
Appearance of test solution
Appearance of the test solutions were observed at the start of the exposure and before the renewal (after 24 hours).
Condition of test solutions
Dissolved oxygen concentration, pH and temperature of the test solutions were measured at the start of the exposure, before and after the renewal and the end of the exposure. At the preparation, another solution sampled from the container for preparation was used for the measurement. At 24 hours after, the measurement was carried out for one test vessel in each level. The dissolved oxygen concentration measurements were carried out with an oxygen meter (YSI Incorporated., YSI Model 58). The pH measurements were carried out with a portable pH meter (DKK-TOA, Model HM-21P). The temperature measurements were carried out with a calibrated red alcohol thermometer of glass stick type.
Concentration of test item in test solution
The concentration of the test item in the test solutions was measured at the start of the exposure, before and after the renewal and the end of the exposure. Since the test item was hydrolyzed and produced 2-(perfluorohexyl) ethanol (abbreviation: 13F-EtOH which is the test item of study number 94232 to 94234), the concentration of 13F-EtOH was also measured. At the start of the exposure and after the renewal (at the preparation) another solution sampled from the container for preparation was used for analysis. Before the renewal and the end of the exposure, the test solution for analysis was taken out with equal volume from the middle layer of the test solution in test vessels in each test level, and mixed. The concentrations of the test item and 13F-EtOH were analyzed by gas chromatography (GC).
Reference substance (positive control):
no
Duration:
48 h
Dose descriptor:
LC50
Effect conc.:
> 0.306 mg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
test mat.
Basis for effect:
mortality (fish)
Duration:
96 h
Dose descriptor:
LC50
Effect conc.:
> 0.306 mg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
test mat.
Basis for effect:
mortality (fish)
Duration:
96 h
Dose descriptor:
LC50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mortality (fish)
Details on results:
The LC50 values were estimated as ‘ > the test concentration” since less than 50% of mortality was observed in the exposure leveL
The results of the study were estimated based on a geometric mean of the measured concentrations as the test concentration.
Results with reference substance (positive control):
not applicable
Reported statistics and error estimates:
no data
Validity criteria fulfilled:
yes
Conclusions:
This study was conducted as a limit test at the concentration around solubility of the test item in dilution water to confirm the effect on the test organisms. It was concluded that the test item has no acute toxicity to the test organisms at the concentration around water solubility, since the measured concentrations of the test solutions at the preparation were around the solubility in dilution water and no effect on the test organisms was observed under the test condition.

Description of key information

LC50 (96 hrs, Medaka-Oryzias latipes) according to OECD guideline 203 (Fish, Acute Toxicity Test): >0.306 mg/L (geom. mean of measured concentration), performed as limit test. Since this concentration was considered to be around solubility of the substance, LC50 96h (nominal) is reported as >100 mg/L.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish
Effect concentration:
100 mg/L

Additional information

The GLP study was conducted as a limit test in order to confirm the effect of the test item on the test organisms at the concentration around the solubility of the test item in dilution water. Although all measured concentrations of the test item in the test solution at the preparation during the exposure were greater than the solubility measured concurrently with the definitive study, they decreased at the 24 hours after the preparation. The reason why the concentration of the test item in the test solution decreased might be due to the characteristics of volatile of the test item and hydrolysis of the test item proceeded gradually with time during the exposure. This study was performed using semi-static replace regime at every 24 hours in order to hold the concentration of the test item as much as possible. Therefore, this study is thought to be appropriate as a test with the concentration around the solubility in the dilution water. This definitive study complied with the test conditions since the environmental conditions in the test were also within the suitable range. Since no adverse effect was found under the condition in the definitive study, it was concluded that the test item had no adverse acute effect on the test organisms at the concentration around the solubility in dilution water. In addition, it is supposed 13F-EtOH of the hydrolyzed product had the additive effect on the test organisms since no adverse effect was observed in the study although the measured concentrations of that in the test solution were 0.0179 to 0.284 mg/L.