1-Butanone, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-

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:

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:

- Concentration: undiluted filtrate with a loading rate of 100 mg/L

For the analysis of the actual test item concentrations, the following samples were taken:
- just before the start of the test: duplicate samples from the test medium and duplicate samples from the control
- after 48 and 96 hours (stability samples): duplicate samples from the test medium and duplicate samples from the control

All samples were taken from the approximate center of the aquaria without mixing of the test media and were kept deep-frozen (at about -20°C) immediately after sampling.

The concentrations of the test substance were analyzed in the duplicate test medium samples from the sampling times at 0 and 96 hours.
From the control samples only one of the duplicate samples was analyzed from the corresponding sampling times.

Vehicle:

no

Details on test solutions:

According to the results of a pre-experiment (without GLP), the test item was not soluble at a concentration of 100 mg/L in test water and no homogeneous dispersion could be prepared.
Therefore, a filtrate of a supersaturated dispersion of the test item was prepared. The undiluted filtrate was tested as the only test concentration. Additionally, a control was test in parallel (test water without test item).

The preparation of the test media was performed as far as possible in the dark to avoid photolytic degradation of the test item during handling. A supersaturated dispersion with a nominal concentration of 100 mg/L (= loading rate) was prepared by weighing 701 mg of the test item into 7 L test water. No auxiliary solvent or emulsifier was used. The test item was mixed into the test water as homogeneously as possible by ultrasonic treatment for 15 minutes and by intense stirring for 3 hours at room temperature in the dark to dissolve a maximum concentration of the test item in the dispersion.The stirring period of 3 hours was chosen according to the results of a pre-test (without GLP) which showed that the solution equilibrium was reached after this time. In this pre-test the same test item concentrations were analytically measured in filtrates after stirring for 3, 24 and 96 hours.
Then, the supersaturated dispersion of the test item was filtered through a membrane filter (Schleicher & Schuell, Type NC45, pore size 0.45 μm) just before introduction of the fish (= start of the test). The undiluted filrate of the supersaturated dispersion with the maximum concentration of dissolved test item was used as the only test medium.

The test concentrations were based on the results of a range-finding test and the results of pre-experiments to the solubility of the test item (without GLP).

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

The study was performed with zebra fish (Brachydanio rerio), obtained from Zoohaus Schaub, 4410 Liestal, Switzerland.

In accordance with the test guidelines, the fish were held in the laboratories for more than 6 weeks without any medication. Prior to the test start, they were acclimated for one week to the test water and temperature.
During holding and acclimatization until one day before the start of the test, the fish were fed with a commercial fish diet (TETRA MIN Hauptfutter, supplied by TETRA-Werke, 49304 Melle, Germany).
During holding and acclimatization no fish died in the test fish batch and all fish were healthy.

From the acclimated test fish batch, 10 fish were measured at the start of the test.
The mean body length of the fish was 3.4 +/- 0.12 cm and the mean body wet weight was 0.58 +/- 0.10 g.

Test type:

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:

22°C

pH:

7.9 at the start of the test (t = 0h) and 7.8-7.9 at the end of the start (t = 96 h)

Dissolved oxygen:

8.4-8.8 mg/L at the start of the test (t = 0h) and 8.3-8.5 mg/L at the end of the start (t = 96 h)

Nominal and measured concentrations:

Nominal concentration: undiluted filtrate of the supersaturated
Measured concentration: 0.28 mg/L at the start of the test and 0.06 mg/L at the end of the test (mean measured concentration: 0.17 mg/L)

Details on test conditions:

TEST SYSTEM
- Material, size, headspace, fill volume: One glass aquarium with 5 L test medium
- Aeration: slightly aerated
- No. of organisms per vessel: 7 fish
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: < 1 g fish wet weight/L

TEST MEDIUM / WATER PARAMETERS
Reconstituted water: analytical grade salts were dissolved in deionized water to obtain the following nominal concentrations:
- CaCl2 x 2H2O: 2.0 mmol/L (= 294 mg/L)
- MgSO4 x 7 H2O: 0.5 mmol/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)
- Ratio of Na:K: 10:1 (based on molarity)
The test water was aerated until oxygen saturation was obtained.

OTHER TEST CONDITIONS
- Since the test item is not stable under light conditions, the test was performed as far as possible in the dark to avoid photolytical degradation of the test item. The aquaria were wrapped with black plastic foil.

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- The test fish were observed after approximately 3, 24, 48, 72 and 96 hours test duration for martality and visible abnormalities.

TEST CONCENTRATIONS
- The test concentrations were based in the results of a range-finding test and the results of pre-experiments 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.

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.

Basis for effect:

mortality (fish)

Remarks on result:

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

Details on results:

The analytically determined test item concentration in the samples from the freshly prepared test medium (the undiluted filtrate of the supersaturated dispersion) amounted to 0.28 mg/L at the start of the test. In this test medium the measured concentration of the test substance decreased to 0.06 mg/L after 96 hours. This decrease of the measured test item concentration might have been due to degradation of the test item.

The biological results are based on the loading rate of 100 mg/L respectively the mean measured test item concnetration of the undiluted filtrate of 0.17 mg/L (calculated as the average over all measurements during the test period).

In the control and in the undiluted filtrate with a loading rate of 100 mg/L (mean measured concentration of 0.17 mg/L), no mortality or other visible abnormalities were determined during the test period of 96 hours.

The 96-hour NOEC (highest concentration tested without toxic effects after the exposure period of 96 hours), and the 96-hour LCO of the test substance respectively its degradation products to zebra fish were determined to be at a loading rate of 100 mg/L (mean measured concentration of 0.17 mg/L). The 96-hour NOEC and the 96-hour LCO might even be higher, but concentrations in excess of 0.17 mg/L could not be tested due to the low water solubility of the test item.
The 96-hour LOEC (lowest concentration with toxic effects), the 96-hour LC50 and the 96-hour LC100 were clearly higher than a loading rate of 100 mg/L (mean measured concentrafion of 0.17 mg/L). These values could not be quantified, since the test item and its degradation products had no toxic effect on the test fish up to highest test item concentration which could be dissolved in the 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 .

Results with reference substance (positive control):

not applicable

Validity criteria fulfilled:

yes

Conclusions:

No acute toxic effects occur within the range of solubility. The test substance is with high probability not acutely harmful to fish.

Executive summary:

In this guideline (OECD 203) study conducted to GLP standards, the 96 hour LD50 of the test material (EC 438-340-0) was determined have no acute toxic effects within the range of solubility. The test was conducted on zebra fish under static conditions. The test result does not trigger classification and labelling of the test material under the criteria of the EU Classification, Labelling, & Packaging (CLP) regulation (1272/2008).

Description of key information

Study conducted to recognised testing guidelines with GLP.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

100 mg/L

Additional information

No acute toxic effects occur within the range of solubility. The test substance is with high probability not acutely harmful to fish.

The study (RCC Ltd. 2002h) was performed according to OECD guideline 203 and GLP as a limit test of 100 mg/L. Due to the low solubility in test water a saturated solution has been prepared. The 96 -hour NOEC and the 96 -hour LC₀were determined to be at least 100 mg/L (the NOEC might even be higher). The 96 -hour LOEC and the 96 -hour LC₅₀were clearly higher than 100 mg/L (loading rate). No mortality or visible abnormalities were observed during the test period of 96 hours.