2,6-dimethylmorpholine

Short-term toxicity to fish

Administrative data

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non-GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1988

Report date:

1988

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: DIN 38412 part 15

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

2,6-dimethylmorpholine

EC Number:

205-509-3

EC Name:

2,6-dimethylmorpholine

Cas Number:

141-91-3

Molecular formula:

C6H13NO

IUPAC Name:

2,6-dimethylmorpholine

Details on test material:

- Name of test material (as cited in study report): 2,6-Dimethylmorpholine (cis/trans isomere mixture)
- Analytical purity: 98.6 %

Sampling and analysis

Analytical monitoring:

no

Test solutions

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: The test substance was added to the test water without any pretreatment, subsequently the fish were placed into the aquaria.
- Evidence of undissolved material (e.g. precipitate, surface film, etc): At the beginning of the test undissolved test substance was visible increasing with an increase in the concentration. Undissolved test substance was not observed at the end of the test.

Test organisms

Test organisms (species):

Leuciscus idus

Details on test organisms:

TEST ORGANISM
- Common name: Golden orfe (Leuciscus idus)
- Source: Fischzucht Paul Eggers, 2354 Hohenweststedt, Germany
- Length at study initiation (length definition, mean, range and SD): 7.8 cm (range 6.6 - 9.1 cm)
- Weight at study initiation (mean and range): 4.7 g (range 3.1 - 6.7 g)
- Feeding during test: Withdrawal of food 1 day before and during exposure

HOUSING
- Housing water: charcoal filtered dechlorinated water in continuous flow-through
- Aeration: oilfree air
- Light regime: 16 : 8 hours light : dark
- Hardness: 2.5 mM
- Oxygen concentration: > 60 % of maximum saturation
- pH: about 8.0
- Water temperature: 11 - 20 °C
- Duration of housing: about 6 month
- Medical treatment: Thrice with 0.05 mg/L malachite green chloride and once with 10 mg/L tetracycline hydrochloride
- Feeding: Growing feed, F/B 50, SSNIEF Spezialdiaeten GmbH, Soest, Germany
- Amount of feed: ad libitum
- Mortality during the last 2 weeks of housing: about 0.8 %

ACCLIMATION
- Acclimation period: about 2 weeks
- Acclimation conditions: same as test
- Acclimation to test water and test temperature: 3 days
- Mortality during acclimation: none
- Type and amount of food: Growing feed, F/B 50, SSNIEF Spezialdiaeten GmbH, Soest, Germany
- Feeding frequency: ad libitum

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Test conditions

Hardness:

2.5 mM

Test temperature:

21 °C

pH:

7.8 - 9.9

Dissolved oxygen:

6.9 - 9.0 mg/L

Nominal and measured concentrations:

Nominal test concentrations: control, 46.4, 100, 215, 464, 1000 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type: open
- Material, size, fill volume: glass aquaria, 30 x 22 x 24 cm
- Aeration: aeration with oil-free air
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: 4.7 g fish /L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: reconstituted freshwater according to DIN 38412, part 11
- Ca/Mg ratio: 4 : 1
- Intervals of water quality measurement: 1, 24, 48, 72, and 96 hours

OTHER TEST CONDITIONS
- Photoperiod: 16:8 hour light:darkness

EFFECT PARAMETERS MEASURED: mortality, symptoms after 1, 4, 24, 48, 72, 96 hours

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2.2
- Range finding study: yes
- Results used to determine the conditions for the definitive study: between 100 and 1000 mg/L

Reference substance (positive control):

yes

Remarks:

Chloroacetamide

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks on result:

other: data refer to an unneutralised test sample

Effect concentrations 2

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

146.63 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: geometrical mean value; data refer to an unneutralised test sample

Effect concentrations 3

Duration:

96 h

Dose descriptor:

LC100

Effect conc.:

215 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: data refer to an unneutralised test sample

Details on results:

- Behavioural abnormalities:
Control: none
46.4 mg/L: none
100 mg/L: none
215 mg/L: tumbling (24 h)
464 mg/L: apathy (1 h), narcotic-like state (4 h)
1000 mg/L: none

- Mortality of control: none

Results with reference substance (positive control):

LC50 after 48 h: ca. 32 mg/L (determined 1988-04-18)

Any other information on results incl. tables

Sublethal observations / clinical signs:

Cumulative mortality

Nominal conc.(mg/l)	Number of fish	Mortality (cumulated) after
		1 h	4 h	24 h	48 h	72 h	96 h
0	10	0	0	0	0	0	0
46.4	10	0	0	0	0	0	0
100	10	0	0	0	0	0	0
215	10	0	1	9	10	10	10
464	10	0	9	10	10	10	10
1000	10	10	10	10	10	10	10