CGL 210

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

May 2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

- Duplicate samples taken from the freshly prepared test medium of the single test concentration and the control at the start of the test (Day 0) and at the last test medium preparation on Day 3.
- Duplicate samples taken out of the single test medium and the control at the end of the first test medium renewal period (Day 1) and at the end of the last test medium renewal (Day 4)

All samples were taken from the approximate center of the aquaria without mixing of the test medium, and were deep-frozen (at about -20°C) immediately after sampling.
The concentration of the test substance was analyzed in all test medium samples from all sampling times. From the control samples only one of the duplicate samples was analyzed from the corresponding sampling times.

Vehicle:

no

Details on test solutions:

- A water accommodated fraction with a loading rate of 100 mg/L was tested as this test item contains several compounds with different physical-chemical properties.
Due to the low water solubility of the test item a supersaturated dispersion with a loading rate of 100 mg/L was prepared daily by dispersing 500 mg of the test item in 5 liters test water. For this, ultrasonic treatment for 15 minutes and intense stirring on a magnetic stirrer for seven days at room temperature in the dark was applied.
Then, the supersaturated dispersion of the test item was filtered through a membrane filter (Schleicher & Schuell, Type NC45, pore size 0.45 μm) after the seven days stirring period.
The test medium was prepared just before introduction of the fish (= start of the test) and prior to each test medium renewal. The undiluted filtrate of the supersaturated dispersion was used as test medium.
- No auxiliary solvent or emulsifier was used.
- A control (test water without test item) was tested in parallel.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: Zebra fish
- Source: from Zoohaus Schaub, 4410 Liestal, Switzerland
- Length at study initiation (length definition, mean, range and SD): 3.0 +/- 0.2 cm
- Weight at study initiation (mean and range, SD): 0.25 +/- 0.04 g
- Method of breeding: held in the laboratories of RCC for more than 4 weeks without any medication
- Food type: Commercial fish diet (TETRA MIN Hauptfutter, supplied by TETRA-Werke, 49304 Melle, Germany)
- No feeding during the test

ACCLIMATION
- Acclimation period: one week
- Acclimation conditions (same as test or not): yes
- Type and amount of food: commercial fish diet (TETRA MIN Hauptfutter, supplied by TETRA-Werke, 49304 Melle, Germany)
- Feeding frequency: until one day before the start of the test
- Health during acclimation (any mortality observed): no mortality

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

2.5 mmol/L (= 250 mg/L) as CaCO3

Test temperature:

21°C

pH:

Control: pH = 7.9-8.0
Test substance: pH = 7.9-8.0

Dissolved oxygen:

Control: 8.3-8.6 mg/L
Test substance: 8.1-8.6 mg/L

Nominal and measured concentrations:

Nominal concentration: water accomodated fraction with a loading rate of 100 mg/L
Measured concentration: < 0.010 mg/L (< LOQ)

Details on test conditions:

TEST SYSTEM
- Material, size, headspace, fill volume: Glass aquarium with 5 L test medium for each treatment
- Aeration: slightly
- Renewal rate of test solution (frequency/flow rate): The test medium was renewed dailydaily
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: 0.34 fish water/L test medium

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: reconstituted water: analytical grade salts were dissolved in deionized water to obtain the folowing nominal concentrations:
CaCl2 x 2H2O: 2.0 mmol/L (= 294 mg/L), MgSO4 x 7 H2O: 0.5mmol/L (= 123 mg/L), NaHCO3: 0.75 mmol/L (= 65 mg/L), KCl: 0.075 mmol/L (= 5.8 mg/L)
- Alkalinity: 0.8 mmol/L
- Ratio of Ca:Mg = 4:1 (based on molarity) and ratio of Na:K = 10:1 (based on molarity)
- The test water was aerated prior to the preparation of the test medium until oxygen saturation was reached.
- Intervals of water quality measurement: pH values, oxygen concentrations and water temperature were measured in the single test medium and the control prior to the introduction of the fish.
These parameters were measured every day during the test in the freshly prepared and aged test medium.
At the same time, the appearance of the test medium was recorded.

OTHER TEST CONDITIONS
- Photoperiod: 16h light/8h dark (with a 30 minute transition period)
- Light intensity: approximately 50- 500 Lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- The fish were observed after approximately 2.5, 24, 48, 72 and 96 hours test duration for mortality and visible abnormalities

TEST CONCENTRATIONS
- The test concentration was based on the results of a range-finding test and on results of a pre-experiment to the solubility of the test item (without GLP)

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

(loading rate)

Basis for effect:

mortality (fish)

Remarks on result:

other: No acute toxic effects within the range of solubility.

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

(loading rate)

Basis for effect:

mortality (fish)

Remarks on result:

other: No acute toxic effects within the range of solubility.

Details on results:

The analytically measured test item concentration in the analyzed test medium samples (the undiluted filtrate of the supersaturated dispersion) was below the limit of quantification of the analytical method (< 0.010 mg/L) at the start and the end of the test medium renewal periods
The biological results are therefore related to the loading rate of the test item of 100 mg/L.
In the control and at the loading rate of 100 mg/L no mortality or visible abnormalities were determined during the test period of 96 hours.
Therefore, the 96-hour NOEC (highest concentration tested without toxic effects after the exposure period of 96 hours), and the 96-hour LC0 of the test substance to zebra fish were determined to be at least at the loading rate of 100 mg/L. The 96-hour NOEC and the 96-hour LC0 might even be higher but loading rates in excess of 100 mg/L have not been tested, according to the guidelines.
The 96-hour LOEC (lowest concentration with toxic effects), the 96-hour LC50 and the 96-hour LC100 were clearly higher than the loading rate of 100 mg/L. These values could not be quantified, since the test item had no toxic effect up to the highest concentration, which could be dissolved in test water.
No remarkable observations were made concerning the appearance of the test medium. The test medium was a clear solution throughout the whole test duration

Validity criteria fulfilled:

yes

Conclusions:

The test substance had no acute toxic effects on zebra fish up to its solubility limit in test water under the present test conditions.

Description of key information

With high probability acutely not harmful to fish. No acute toxic effects occur within the range of solubility.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Effect concentration:

> 100 mg/L

Additional information

A study was performed according to OECD guideline 203 (RCC Ltd. 2002e) as a limit test of 100 mg/L (nominal concentration). Due to the low water solubility of the test item a supersaturated dispersion with a loading rate of 100 mg/L was prepared daily.The actual measured concentration was below the limit of quantification of the analytical method (< 0.010 mg/L) measured at the start and at the end of the test medium renewal periods. The LC₀ and LC₁₀₀ are both higher than 100 mg/L. No mortality or visible abnormalities were observed during the test period of 96 hours (NOEC (96h) ≥ 100 mg/L).