3-aminopropyltriethoxysilane

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1993-10-11 to 1994-10-15

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Principles of method if other than guideline:

DIN 38412 Part 1; EG Guideline 92/69 C.1; OECD Guideline 203, 1984

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

The only treatment was sampled at the start of the test

Vehicle:

no

Details on test solutions:

A test medium was prepared at a nominal concentration of 1.0 g/L by mixing for 18 hours followed by filtration. Analysis of the medium showed it to contain 934 mg/L of the substance.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM

- Common name: Zebrafish

- Source: West Aquarium, Bad Lauterburg, Germany

- Length at study initiation: 3.0+/-0.5 cm

- Feeding during test: none


ACCLIMATION

- Acclimation period: 14-days

- Acclimation conditions: same as test

- Type and amount of food: Tetramin® at 1% of body weight

- Feeding frequency: Daily

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

10.7ºdH

Test temperature:

20-21ºC

pH:

7.8-8.4 in Control

8.2-9.3 in Treatment

Dissolved oxygen:

8.0-8.9 mg/L in Control

7.8-9.0 mg/L in Treatment

Salinity:

Not applicable

Nominal and measured concentrations:

Nominal concentrations: 0 (Control) and 1000 mg/L

Measured concentrations: 880 mg/l at 0 hours; 922/947 mg/l at 24 hours; 885 mg/l at 72 hours; average value of 934 mg/l (water filtered initial solution).

Measured concentration in treated media: 934 mg/L

Details on test conditions:

TEST SYSTEM

- Test vessel: 20 litre aquarium

- Type (delete if not applicable): open

- Aeration: Yes, continuous

- Renewal rate of test solution: daily

- No. of organisms per vessel: 10

- No. of vessels per concentration (replicates): 1

- No. of vessels per control (replicates): 1


TEST MEDIUM / WATER PARAMETERS

- Source/preparation of dilution water: Potable water from Gelsenwasser AG

OTHER TEST CONDITIONS

- Adjustment of pH: No

- Photoperiod: 16 hours light, 8 hours dark


EFFECT PARAMETERS MEASURED: Daily mortalities


TEST CONCENTRATIONS

- Spacing factor for test concentrations: Limit test

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

>= 934 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 934 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

- Mortality of control: 0

· Abnormal responses:  None reported

Reported statistics and error estimates:

No effects were observed in the test and therefore statistical analysis was not required.

Sublethal observations / clinical signs:

No effects were observed in Control or treated media.

Validity criteria fulfilled:

yes

Conclusions:

A 96-hour LC50 of >934 mg/L and NOEC of =934 mg/L have been determined for the effects of the test substance on mortality of Brachydabio rerio. It is likely that the test organisms were exposed predominantly to the hydrolysis products of the substance.

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

2002-08-26 to 2003-01-10

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

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0(Control) and 100 mg/l

- Sampling method: Duplicate samples of test media were taken at the start and end of the test.

- Sample storage conditions before analysis: samples were analysed immediately after collection.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION

- Method: Three, four litre volumes of test media with a nominal concentration of 100 mg/l were prepared by intense stirring for 24 hours. The three volumes were then aggregated to produce the final test medium.

- Controls: Dilution water

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM

- Common name: Rainbow trout

- Source: Forellenzuchtbetrieb Tautenhahn, 98646 Trostadt, Germany

- Length at study initiation (length definition, mean, range and SD): 5.13 +/-0.39 cm

- Weight at study initiation (mean and range, SD): 1.26 +/-0.23 g

ACCLIMATION

- Acclimation period: 4 weeks

- Acclimation conditions (same as test or not): yes

- Type and amount of food: commercial fish food

- Health during acclimation (any mortality observed): no mortalities observed

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

250 mg/l as CaCO3

Test temperature:

15-17ºC

pH:

7.7-7.9

Dissolved oxygen:

=8.7 mg/l

Salinity:

not applicable

Nominal and measured concentrations:

Nominal concentrations: 0(Control) and 100 mg/l

Measured concentrations were 88% of nominal at the start of the test and 76% at the end of the test. The mean measured concentration was therefore 82 mg/L.

The test results are reported and interpreted with reference to nominal concentrations.

Details on test conditions:

TEST SYSTEM

- Test vessel: aquaria

- Type (delete if not applicable): open

- Material, size, headspace, fill volume: glass, 20 litre capacity with 12 litre of test medium

- Aeration: yes

- Renewal rate of test solution (frequency/flow rate): none

- No. of organisms per vessel: 7

- No. of vessels per concentration (replicates): 1

- No. of vessels per control (replicates): 1

- Biomass loading rate: 0.74 g/l

TEST MEDIUM / WATER PARAMETERS

- Source/preparation of dilution water: Reconstituted freshwater prepared by adding analytical grade salts to deionised water.

- Alkalinity: 0.8 mmol/l

- Ca/mg ratio: 4:1

- Culture medium different from test medium: no

- Intervals of water quality measurement: daily

OTHER TEST CONDITIONS

- Adjustment of pH: no

- Photoperiod: 16 h light, 8 h dark

- Light intensity: 320-420 lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): mortality after 2, 24, 48, 72 and 96 hours

TEST CONCENTRATIONS

- Spacing factor for test concentrations: not applicable

- Range finding study

- Test concentrations: not reported

- Results used to determine the conditions for the definitive study: not reported

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

but exposure is to hydrolysis products

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

but exposure is to hydrolysis products

Basis for effect:

mortality (fish)

Details on results:

- Behavioural abnormalities: none

- Mortality of control: 0

Reported statistics and error estimates:

There were no toxic effects observed in the test and therefore no statistical tests were required.

Sublethal observations / clinical signs:

No toxic effects were observed following 96 hours exposure to a nominal concentration of 100 mg/l.

Validity criteria fulfilled:

yes

Conclusions:

A 96-hour LC50 value of >100 mg/l and NOEC of =100 mg/l have been determined for the effects of the test substance on mortality of Oncorhynchus mykiss based on nominal concentration of the substance. The test substance is susceptible to hydrolysis and it is likely that the test organisms were primarily exposed to the hydrolysis products of the substance.

Description of key information

96 hour LC₅₀: >934 mg/l, mortality of Brachydanio rerio; equivalent to >579 mg/l as 3-aminopropylsilanetriol.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

EC50

Effect concentration:

> 579 mg/L

Additional information

A 96-hour LC₅₀ of >934 mg/L (measured DOC concentration) (highest concentration tested) has been determined for the effects of 3-aminopropyl(triethoxy)silane (CAS 919-30-2) on mortality of Brachydanio rerio (tested as Danio rerio), in accordance with OECD Test Guideline 203 and in compliance with GLP (Hüls, 1994a).

The test substance is susceptible to hydrolysis and, due to the test media preparation (stirring for 18 hours) and exposure regime (semi-static), it is likely that the test organisms were predominantly exposed to the hydrolysis products of the substance. Concentration measured by DOC is non-specific, therefore the measured DOC concentration is likely to reflect the concentration of the hydrolysis products, 3-aminopropylsilanetriol and ethanol.

Because the measured DOC concentration is within 20 % of the nominal parent test substance concentration of 1000 mg/l, the results may be expressed in terms of concentration of the silanol hydrolysis product, 3-aminopropylsilanetriol, by applying a molecular weight correction: (MW of silanol = 137.21 / MW of parent = 221.37) * >934 mg/L = >579 mg/L.

The registration substance is susceptible to hydrolysis reaction of the alkoxysilane groups (to silanols) and to potential condensation reactions (described in Section 4.8 of IUCLID and Section 1.4 of the CSR). Pre-hydrolysis and filtration were used as part of media preparation. Analytical recoveries by DOC were high (within 20% of nominal). Models would suggest that the irreversible condensation is unlikely for these silanol hydrolysis products at the concentrations relevant to the studies (PFA, 2016am). 

 

These findings are supported by a 96-hour LC₅₀ in rainbow trout >100 mg/l, determined for 3-(trimethoxysilyl)propyl isocyanate (CAS 15396-00-6) conducted according to OECD Test Guideline 203 and in compliance with GLP (IBACON, 2003). For this substance the isocyanate group is very rapidly hydrolysed to the corresponding amine (half-life of minutes or less), and further hydrolysis of the alkoxy groups proceeds at a slower rate (half-life of 2.8 h at pH 7 and 20-25 °C, estimated) to 3-aminopropylsilanetriol and methanol.