Morpholine, 4-[(triethoxysilyl)methyl]-

Short-term toxicity to fish

Administrative data

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2005-08-04 to 2005-09-06

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: OECD Guideline under GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2005

Report date:

2005

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: 92/69/EWG, C.1; OECD 203 (1992)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

480-370-1

EC Name:

-

Cas Number:

21743-27-1

Molecular formula:

Hill formula: C11H25NO4Si CAS formula: C11H25NO4Si

IUPAC Name:

4-[(triethoxysilyl)methyl]morpholine

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0 and 110 mg/L nominal (110 mg/L in duplicate)
- Time points: 0 and 96 h
- Sample storage conditions before analysis: freezer

Test solutions

Vehicle:

no

Details on test solutions:

Identity and concentration of auxiliary solvent for dispersal: No vehicle used.
Test solutions were prepared according to the guidance document on aquatic toxicity testing of difficult substances:
A stock solution of the only test concentration of nominal 110 mg/l was prepared by dissolving 550 mg test item into 5000 ml test water by intense stirring for 24 h and additional short ultrasonic treatment for 5 min.
Since the test item undergoes rapid hydrolysis and as there was no specific analytical method available, analyses was performed by determination of the TOC (Total organic carbon) content as sum parameter in the test media.
At the start of the test the mean measured test item concentration was 111 mg/l. During the test period of 96 h a decrease of the test item concentration to 81.4 mg/l was determined. Therefore the biological results were related to the mean measured test item concentration 95.7 mg/l.

Test organisms

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: Rainbow trout
- Strain: Oncorhynchus mykiss
- Source: Forellenzuchtbetrieb Wagenhausen, Bad Solgau, Germany
- Age at study initiation (mean and range, SD): juvenil
- Length at study initiation (length definition, mean, range and SD): 5.12 +/-0.21 cm
- Weight at study initiation (mean and range, SD): 1.34 +/- 0.1 g
- Method of breeding: not given
- Feeding during test: none



ACCLIMATION
- Acclimation period: 12 days
- Acclimation conditions (same as test or not): same as in test
- Type and amount of food: not given
- Feeding frequency: not given
- Health during acclimation (any mortality observed): 3 fish in the test fish batch

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Post exposure observation period:

-

Test conditions

Hardness:

250 mg CaCO3/L

Test temperature:

15-16 °C

pH:

7.6-7.9

Dissolved oxygen:

> 9.1 mg/L

Salinity:

0.8 mmol/L

Nominal and measured concentrations:

nominal: 110 mg/L
measured (mean): 95.7

Details on test conditions:

TEST SYSTEM
- Test vessel: 20-Litre glass aquaria with 15 litre test medium
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: not given


TEST MEDIUM / WATER PARAMETERS
see above


OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 h/d
- Light intensity: 450-550 lux


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
The test fish were observed after approximately 2, 24, 48, 72, 96 hours test duration for symptoms of intoxication and mortality.


TEST CONCENTRATIONS
- Limit test
- Range finding study
- Test concentrations: max. 100mg/L nominal

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 95.7 mg/L

Nominal / measured:

meas. (arithm. mean)

Basis for effect:

mortality (fish)

Effect concentrations 2

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

>= 95.7 mg/L

Nominal / measured:

meas. (arithm. mean)

Basis for effect:

mortality (fish)

Effect concentrations 3

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

>= 95.7 mg/L

Nominal / measured:

meas. (arithm. mean)

Basis for effect:

other: toxic effects

Details on results:

- Behavioural abnormalities: no
- Observations on body length and weight: no
- Other biological observations:
- Mortality of control: no
- Other adverse effects control: no
- Abnormal responses: no
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: no
- Effect concentrations exceeding solubility of substance in test medium: no

After 96 h exposure, one fish at 95.7 mg test item displayed apathy. Since this effect appeared only in one out of seven fish at 95.7 mg test item/L and in addition to this, no dose dependent relationship was determined, the apathy was considered as not treatment relevant.

Results with reference substance (positive control):

n.a.

Reported statistics and error estimates:

not applicable

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Since at a mean concentration of 95.7 mg/L no effect on the test organisms was observed, it can be assumed that the LC 50 is also higher than 100 mg/L. SLM 4490029 was not toxic to fish under the reported conditions.

Executive summary:

To assess the acute toxicity of N-(Morpholinomethyl)triethoxysilane to fish a limit test according to OECD 203 (EU Guideline 92/92/EEC C.1) was performed. In the control and the only test concentration (95.7 mg/L mean measured conc.) no mortality and no treatment related toxic effects were observed. Since at a mean concentration of 95.7 mg/L no effect on the test organisms was observed, it can be assumed that the LC 50 is also higher than 100 mg/L. Based on this N-(Morpholinomethyl)triethoxysilane is not considerd to be toxic to fish.