N-[(triethoxysilyl)methyl]cyclohexylamine

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:

April 15 - June 08, 2004

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

adopted July 17, 1992

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

454-780-6

EC Name:

-

Cas Number:

27445-54-1

Molecular formula:

Hill formula: C12H27NO2Si CAS formula: C12H27NO2Si

IUPAC Name:

Cyclohexyl-((diethoxy-methyl-silanyl)-methyl)-amine

Test material form:

liquid

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Duplicate samples from the freshly prepared test media of all test concentrations and the control were taken at the start of the test. For the determination of the stability of the test item under
the test conditions, respectively the maintenance of the test item concentrations during the test period, samples were taken in duplicate out of all test media at the end ofthe test.
The samples were analysed directly. The rest of the samples was stored in the refrigerator (4 ±4 QC), protected from light and will be kept stored up to the delivery ofthe final report.

Test solutions

Details on test solutions:

The test concentrations were based on the results of a rangefinding test. However, according to the Commission Directive 92/69/EEC concentrations in excess of nominal 100 mg test item/L were not tested.
2.1, 4.6, 10, 21, 46, and 100 mg test item/L. Additionally, a control was tested in parallel (test water without addition of the test item).
Since the test item hydrolyses in water very quickly, in the present test the hydrolysis products of the test item was tested, according to the draft guidance document on aquatic toxicity testing of difficult substances. Therefore, a concentrated stock solution of nominal 500 mg/L was prepared by dissolving 2000 mg test item into 4000 mL test water by intense stirring in darkness for 24 hours. Then, adequate volumes of this stock solution were diluted with test water to prepare the required test media concentrations. The test media were prepared just before introduction of test fish (= start ofthe test).
Thus, the main part of the test item at the start of the test were hydrolysis products.

Test organisms

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

Test system
- Rainbow trout (Oncorhynchus mykiss)
- juveniles, male and female
- Origin: Forellenzuchtbetrieb Tautenhahn, 98646 Trostadt, Germany

Study design

Test type:

static

Water media type:

other: In deionised water analytical grade salts were added to following nominal concentrations: CaC12 x 2H20 2.0 mmol/L, MgS04 x 7H20 0.5 mmol/L, NaHC03 0.75 mmol/L, KCl 0.075 mmol/L, Water Hardness 2.5 mmol/L as CaC03, Alkalinity 0.8 mmol/L

Limit test:

no

Total exposure duration:

96 h

Test conditions

Hardness:

2.5 mmol/L (= 250.0 mg/L) as CaCO3

Test temperature:

13 - 17°C with a maximum deviation of± 1°C

pH:

6.5 - 8.5

Dissolved oxygen:

At least 60 % of the air saturation value

Salinity:

not applicable

Nominal and measured concentrations:

Nominal: 2.1, 4.6, 10, 21, 46 and 100 mg test item/L, and a control (test water without addition of the test item).
For nominal concentrations 2.1, 4.6 and 10 mg/L the measured concentrations were below the limit of quantification, for 21, 46 and 100 mg/L the measured concentrations were in the range of 68-84% of the nominal concentrations.

Details on test conditions:

Test Units:
- 15-litre glass aquaria with 10 litre test medium
- Each test unit was uniquely identified with study number, treatment
Holding Conditions:
- In accordance with the test guidelines the fish were held in test water in the laboratories of IBACON for at least 12 days prior to the start of the test without any medication. During holding until one day before test start the fish were fed with a commercial fish diet for Rainbow trout. During the last 12 days prior to the start of the test no fish died in the test fish batch and all fish were healthy.
- For at least 12 days before the start of the test the fish were acclimated to the test temperature.

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

other: test mat. / but exposure is to hydrolysis product

Basis for effect:

mortality (fish)

Details on results:

In the control and at the test concentrations up to and including actual 35 mg test itemIL all fish survived until the end of the test and no symptoms of intoxication were observed.
At the highest test concentration of nominal 100 mg test item/L, one fish died until the end of the experiment. All other test fish at this and at the lower test concentrations did not show any symptoms until the end of the experiment.

Reported statistics and error estimates:

95 % confidence interval not available

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

A 96-hour LC50 value of > 100 mg/L has been determined for the effects of the test substance on mortality of Oncorhynchus mykiss based on nominal exposure concentrations of the substance. The test substance hydrolyses in water and it is therefore likely that the test organisms were primarily exposed to the hydrolysis products of the substance.