2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one

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:

1983-07-18 to 1983-07-22

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

GLP compliance:

not specified

Analytical monitoring:

yes

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: 100 mg test substance and 10 mg Arkopal were dissolved in 1 ml Dioxane and made up to 1000 ml with water.
- Chemical name of vehicle: Arkopal and Dioxane
- Highest vehicle concentration 330.9 mg/L Dioxane and 3.2 mg/L Arkopal

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: Zebra fish
- Source: West-Aquarium / D-3422 Bad Lauterberg
- Length at study initiation: 30 mm (27 mm - 31 mm)
- Weight at study initiation: 0.26 g (0.16 g - 0.30 g)
- Feeding during test: no


ACLIMATISATION AND ADAPTATION
-Acclimatisation period: 40 days
- Adaptation period: 24 h
- Feeding during adaptation: none

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

194 mg/L CaCO3

Test temperature:

23 ± 1 °C

pH:

8.0 - 8.4

Dissolved oxygen:

0 h: 8.7 - 8.9 mg/L
96 h: 7.7 - 7.9 mg/L

Nominal and measured concentrations:

Nominal test concentrations: 0.0, 3.2, 5.8, 10.0, 18.0, 32.0 mg/L
Measured test concentrations (0 h): n.r., 2.7, 5.0, 7.8, 14.2, 25.9 mg/L
Measured test concentrations (96 h): n.r., 2.9, 4.9, 7.5, 14.9, 19.5 mg/L

n.r.: not reported

Details on test conditions:

TEST SYSTEM
- Test vessel:
Material, fill volume: glass aquaria, 20 L, filled with 15 L
Aeration: gentle aeration
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- No. of vessels per vehicle control (replicates): 1
- Biomass loading rate: 0.17 g/L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: dechlorinated tap water (carbon filter)
- Intervals of water quality measurement: daily (pH, dissolved O2 and temperature)

OTHER TEST CONDITIONS
- Lighting: fluorescent light, 16 h daily


EFFECT PARAMETERS MEASURED: mortality, swimming behaviour, loss of equilibrium, respiratory function exophtalmus, pigmentation; observations daily

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

5.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

9 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% CL: 3.9 - 20.9 mg/L

Duration:

96 h

Dose descriptor:

LC100

Effect conc.:

18 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

Symptoms observations 24 h:
Swimming behaviour at conc. 3.2, 5.8 and 10.0 mg/L
Loss of equilibrium at conc. 10.0 mg/L
Respiratory function at conc. 10.0 mg/L

Symptoms observations 48 h:
Swimming behaviour at conc. 3.2, 5.8 and 10.0 mg/L
Loss of equilibrium at conc. 10.0 mg/L
Respiratory function at conc. 10.0 mg/L

Symptoms observations 72 h:
Swimming behaviour at conc. 3.2, 5.8 and 10.0 mg/L
Loss of equilibrium at conc. 10.0 mg/L
Respiratory function at conc. 10.0 mg/L
Pigmentation at conc. 10.0 mg/L

Symptoms observations 96 h:
Swimming behaviour at conc. 3.2, 5.8 and 10.0 mg/L
Loss of equilibrium at conc. 10.0 mg/L
Respiratory function at conc. 10.0 mg/L
Pigmentation at conc. 10.0 mg/L

No mortality in control and vehicle control

Validity criteria fulfilled:

not specified

Conclusions:

The 96 hour LC50 of the test material was determined to be 9 mg/l under the conditions of the test.

Description of key information

The test was conducted using recognised testing guidelines with some deviation.  Results are considered to be reliable with restrictions.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

9 mg/L

Additional information

A guideline study testing the acute toxicity of the test substance to Danio rerio according to OECD guideline 203 was performed. The determined LC50 (96 h) was 9 mg/L (Ciba-Geigy, 1983). However, an emulsifier has been used and precipitation of the test substance has been observed in the highest test concentration.