Amino functional alkoxysilanes

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

16 - 20 Nov 2004

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

following OSPAR PARCOM Protocol, marine fish, semi-static

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Concentrations: Control and nominal loading rate of 200 mg/L
- Sampling method: 4 mL samples of the test media were taken at the start and end of each successive 48 h exposure period (total exposure period of 96 h)
- Sample storage conditions before analysis: Samples analysed immediately after collection. Retained samples were stored at -20 °C

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: The test item was added to the test vessel containing dilution water and stirred for 1 hour prior to introducing the fish.
- Controls: Dilution water

Test organisms (species):

other: Scophthalmus maximus

Details on test organisms:

TEST ORGANISM
- Common name: Turbot
- Source: Venö Fish Farm, Venö, Denmark
- Diameter at study initiation (mean and SD): 5 +/-1 cm
- Feeding during test: no

ACCLIMATION
- Acclimation period: 15 days
- Acclimation conditions: same as test
- Type and amount of food: DANA Feed 1362, 1.8 mm granulate
- Feeding frequency: Twice per day for at least 5 days per week
- Health during acclimation (any mortality observed): No fish died during the acclimation period

Test type:

semi-static

Water media type:

saltwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

not reported

Test temperature:

14.2-14.7°C

pH:

7.8-8.6

Dissolved oxygen:

≥60% ASV

Salinity:

33.5 ppm

Nominal and measured concentrations:

Control and nominal loading rate of 200 mg/L
Mean measured concentrations of the test substance (based on DOC) were 113 and 118% of nominal in the two replicates.

Details on test conditions:

TEST SYSTEM
- Test vessel: aquarium

- Type: open

- Material, size, fill volume: glass, 10 litre with 7 L fill volume

- Aeration: yes

- Renewal rate of test solution: after 48 hours

- No. of organisms per vessel: 7

- No. of vessels per concentration (replicates): 2

- No. of vessels per control (replicates): 2

TEST MEDIUM / WATER PARAMETERS

- Source/preparation of dilution water: Artificial seawater prepared using "Reef Salt", Aqua Medic GmbH, Bissendorf, Germany by adding 33.5 g/L of salts to tap water and stirring for 24 hours.

- Ca/mg ratio: 1:2.9

- Culture medium different from test medium: no

- Intervals of water quality measurement: Daily

OTHER TEST CONDITIONS

- Adjustment of pH: no

- Photoperiod: 12 h light, 12 h dark

EFFECT PARAMETERS MEASURED: Mortality daily

TEST CONCENTRATIONS

- Spacing factor for test concentrations: Limit test

- Range finding study

- Test concentrations: 1, 10, 50, 100, 200, 500 and 1000 mg/L

- Results used to determine the conditions for the definitive study: No mortality at any concentration

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 200 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

- Mortality of control: 0%

Reported statistics and error estimates:

There were no toxic effects observed in the test and therefore statistical analysis of the results was not required.

Sublethal observations / clinical signs:

Table 1. Results of analysis of test media

 

Nominal test substance concentration (mg/L)	Nominal test substance concentration as TOC (mg/L)	Measured DOC concentration in fresh test medium at start of test (mg/L)	Measured DOC concentration in old test medium after 48 hours (mg/L)	Measured DOC concentration in fresh test medium at 48 hours (mg/L)	Measured DOC concentration in old test medium after 96 hours (mg/L)
0 (Control)	0	8.2	20	18	3.7
200 (Rep. 1)	84	115	97	97	84
200 (Rep. 2)	84	100	97	97	84

 

Since no toxic effects were observed up to the highest tested concentration the NOEC (96 h) was >= 200 mg/L.

Validity criteria fulfilled:

yes

Conclusions:

A 96-h LC50 value of >200 mg/L and a NOEC of ≥200 mg/L have been determined for the effects of the test substance on mortality of the marine fish species Scophthalmus maximus based on nominal exposure concentrations.

Reference 3

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1988-08-08 to 1988-08-12

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION

- Method: The test media were prepared by direct dispersion in water with the aid of shielded propeller stirrers.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM

- Source: Parkwood Trout Farm, Kent, UK.

- Acclimatisation: Stock held since 9 May 1988 and acclimatised to test conditions from 1 - 8 August 1988.

- Temperature: 14 + 2O°C.

- Dissolved oxygen: 29.6 mgO2/L.

- Feeding: Commercial trout pellets daily. Discontinued 24 h prior to test.

- Mortalities: <1% in 7 days prior to test.

- Medication: None.

- Mean standard length: 6.6 cm (SD = 0.2cm).

- Mean weight: 4.40 g (SD = 0.35 g).

The fish were slightly larger than the recommended range given in OECD Guidelines No. 203 but this was not considered to have had a significant
effect on the results of the test. These larger fish were preferred for this particular study in view of the strong circulation currents generated by the shielded propeller stirrers necessary to maintain the test dispersion.

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

350 mg/L as CaCO3

Test temperature:

14°C

pH:

8.0

Dissolved oxygen:

9.8-10.2 mg/L

Salinity:

Not applicable

Nominal and measured concentrations:

Nominal concentrations: 0 (Control), 100, 180, 320, 560 and 1000 mg/L

Details on test conditions:

- Test vessels: Glass aquaria holding 40 1 of test media and fitted with shielded propeller stirrers.

- Experimental design: 5 test concentrations plus 1 control. 10 animals per test concentration.

- Method of initiation: Fish were placed in prepared test media.

- Loading: 1.1 g bodyweight/L

- Photoperiod: 16 h light : 8 h dark

- Temperature: 14+/-1°C.

- Aeration: By shielded propeller stirrers.

- Test concentrations: 100, 180, 320, 560 and 1000 mg/L.

- Medium renewal: Daily

- Duration of exposure: 96 hours

- Criteria of death: Absence of (i) respiratory movement and (ii) response to physical stimulation.

- Dilution water: Laboratory tap water, dechlorinated by the addition of sodium thiosulphate. Total hardness = 350 mg/l as CaCO3. This value is slightly higher than the recommended range but is not considered to have had any significant effects on the results of the test.

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

130 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

but exposure is to hydrolysis products

Basis for effect:

mortality (fish)

Remarks on result:

other: 100-180 mg/L

Key result

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:

- Mortality of control: None

Reported statistics and error estimates:

Analysis of the mortality data to determine LC50 values was by the method of Thompson, W.R. & Weil, C.S. (1952) Biometrics 8, 51-54.

Sublethal observations / clinical signs:

Table 1. Test results

 

Nominal test concentration (mg/L)	Percentage mortality after 24 hours	Percentage mortality after 48 hours	Percentage mortality after 72 hours	Percentage mortality after 96 hours
0 (Control)	0	0	0	0
100	0	0	0	0
180	0	70	100	100
320	0	100	100	100
560	100	100	100	100
1000	100	100	100	100

 

Validity criteria fulfilled:

yes

Conclusions:

A 96-hour LC50 value of 130 mg/L and a NOEC of 100 mg/L have been determined for the effects of the test substance on mortality of Salmo gairdneri (new name: Oncorhynchus mykiss). The test substance hydrolyses rapidly in water and it is therefore likely that the test organisms were primarily exposed to the hydrolysis products of the substance.

Reference 4

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

13 - 17 May 2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Guideline study. The study was conducted according to the appropriate OECD test guideline, and in compliance with GLP.

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

1992

Qualifier:

according to guideline

Guideline:

other: OECD 23 Guidance Documenton Aquatic Toxicity Testing of Difficult Substance and Mixtures 2000

Qualifier:

according to guideline

Guideline:

other: Fish, Acute Toxicity Test stipulaed in the Testing Methods for New Chemical Substances of Japan, 2011

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

- Concentrations: silanol form was measured in all test levels at the start and the end of the exposure. Methanol was measured for the 100 mg/L level (with pH adjustment) and methanol control at the start of the exposure. As the test item hydrolyzes in water and forms silanol and methanol, these both components were measured in the test solutions instead of the test item itself.

- Sampling method: 10 mL of the test solution was taken out from the middle layer of the test vessel.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION

- Method: the test item was added in dilution water while stirring with a magnetic stirrer in Erlenmeyer flask to produce each nominal concentration as silanol form [N,N-bis (3-trihydroxysilylpropyl) amine]. Solutions were stirred with a magnetic stirrer for approx. 2 h. Suspension was filtered with a glass fiber filter and filatrate was re-aerated. In addition the same test solutions for all nominal concentrations were prepared with a final adjustment of the pH to the pH of the dilution water (using HCl).

- Controls: methanol control was made into the same level (75 mg/L) as the theoretical methanol concentration contained in 100 mg/L test solution (theoretical mehtanol concentration = concentration of silanol form * 32.04 (methanol molecular weight) * 6/257.40 (silanol form molecular weight))

Test organisms (species):

Oryzias latipes

Details on test organisms:

TEST ORGANISM
- Common name: medaka

- Source: Ceri Kurume (laboratory production)

- Length at study initiation: 2.3 ± 1.2 cm

ACCLIMATION

- Acclimation period: 12 d for pH unadjusted and 40 d for pH adjusted

- Acclimation conditions (same as test or not): dechlorinated tap water, oxygen concentration not less than 80% of air saturation, 24 ± 1 °C, 16 h light/ 8 h dark

- Type and amount of food: fry or carp crumble 2C (Nippon Formula Feed Mfg.), food amount corresponds to 2% of body weight

- Feeding frequency: every day (no feeding 24 h before start of exposure)

- Health during acclimation (any mortality observed): no mortalities 7 d prior to test start

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Test temperature:

pH unadjusted: 23.7 - 24.1 °C
pH adjusted: 24.4 - 24.7 °C

pH:

pH unadjusted: 7.6 - 9.3
pH adjusted: 7.6 - 7.9

Dissolved oxygen:

pH unadjusted: 7.9 - 8.5 mg/L
pH adjusted: 6.4 - 8.1 mg/L

Nominal and measured concentrations:

0 (control), 35, 46, 59, 77, 100 mg/L (nominal, as silanol form)

Details on test conditions:

TEST SYSTEM

- Test vessel: 3 L glass tank

- Type (delete if not applicable): closed

- Material, size, headspace, fill volume: transparent plastic lid, fill volume: 2.8 L

- Aeration: yes, conducted gently

- No. of organisms per vessel: 7

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

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

- No. of vessels per methanol control: 1

TEST MEDIUM / WATER PARAMETERS

- Source/preparation of dilution water: dechlorinated tap water, aerated

- Intervals of water quality measurement: at the start of the exposure and every 24 h

OTHER TEST CONDITIONS

- Adjustment of pH: the test was run in two parallels, one with and one without adjustment of pH in order to examine pH effects on fish mortality

- Photoperiod: 16 h light/8 h dark

-Light quality: room light

EFFECT PARAMETERS MEASURED : mortality and abnormalities were observed at 3, 24, 48, 72 and 96 h

TEST CONCENTRATIONS

- Range finding study: yes, pH exceeded 9 at the start of the exposure at test concentrations of 59 - 100 mg/L. Mortalities were observed at these cocnentrations and therefore solutions with a pH adjustment were additionaly set up, to observe wether effects were caused by pH or by the test item toxicity.

- Test concentrations: 10 - 100 mg/L

- Results used to determine the conditions for the definitive study: based on the results of the range finding test, concentrations between 35 and 100 mg/L were chosen for the definitive study

Reference substance (positive control):

yes

Remarks:

Copper (II) sulfate pentahydrate

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

57 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: pH unadjusted, 95% CI: 48 - 66 mg/L

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: pH adjusted

Details on results:

- Mortality of control: no mortalities

- Mortality of methanol control: no mortalities

Reported statistics and error estimates:

pH unadjusted: LC50 values of 96 h were calculated by Probit analysis.

pH adjusted: LC50 were estimated as the highest test concentration since the mortality over 50% was not observed

Sublethal observations / clinical signs:

Further effect values after 96 h exposure:

pH unadjusted: NOEC (96 h) = 46 mg/L (nominal)

pH adjusted: NOEC (96 h) = 59 mg/L (nominal)

Size of test organisms at the end of the test:

- pH unadjusted: total length: 2.5 ± 0.2 cm, weight: 0.13 ± 0.02 g

- pH adjusted: total length: 2.5 ± 0.1 cm, weight: 0.13 ± 0.01 g

Test item concentrations at the beginning and at the end of the test:

- pH unadjusted: silanol concentrations at test start: 33 - 100 mg/L (87 - 106% of nominal), silanol concentrations at test end: 35 - 88 mg/L (88 - 108% of nominal), methanol concentration at test start in methanol control and test level of 100 mg/L: 81 and 78 mg/L (108 and 103% theoretical formed concentration), respectively.

- pH adjusted: silanol measured concentrations at test start: 39 - 110 mg/L (111 - 119% of nominal), measured concentrations at test end: 37 - 110 mg/L (105 - 111% of nominal)

Table 1: Cumulative mortalities in %.

pH unadjusted
Nominal concentrations [mg/L]	Cumulative mortality in %
	3 h	24 h	48 h	72 h	96 h
Control	0	0	0	0	0
Methanol control	0	0	0	0	0
35	0	0	0	0	0
46	0	0	0	0	0
59	0	0	0	57	86
77	0	0	0	57	86
100	0	14	57	86	100
pH adjusted
Nominal concentrations [mg/L]	Cumulative mortality in %
	3 h	24 h	48 h	72 h	96 h
Control	0	0	0	0	0
Methanol control	0	0	0	0	0
35	0	0	0	0	0
46	0	0	0	0	0
59	0	0	0	0	0
77	0	0	0	0	14
100	0	0	0	0	29

Validity criteria fulfilled:

yes

Conclusions:

A 96 h EC50 value of > 100 mg/L was determined when the pH was adjusted while 96 h EC50 was 57 mg/L when pH was unadjusted. NOEC (96 h) was found to be 46 mg/L (nominal) when pH was unadjusted and 59 mg/L (nominal) when the pH was adjusted to the pH of the dilution water.

Reference 5

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1994-04-26 to 1994-04-30

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Guideline study. The study was conducted according to the appropriate EU test method, and in compliance with GLP. The study is considered reliable without restrictions.

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

not specified

Details on sampling:

- Concentrations: 500 mg/L

- Sampling method: Samples of test media were taken from all treatments at the start and end of the first (0-24h) and third (48-72h) test periods.

- Sample storage conditions before analysis: refrigerated

Vehicle:

not specified

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION

- Method: A stock solution was prepared by mixing the substance overnight with dilution water used in the test

- Controls: Dilution water

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM

- Common name: Zebrafish

- Source: Tropical Waters (Feltham, UK)

- Age at study initiation (mean and range, SD):

- Length at study initiation (length definition, mean, range and SD): 3.4 cm (3.1 - 3.7 cm)

- Weight at study initiation (mean and range, SD): 0.38 g (0.3 - 0.45 g)

- Feeding during test: None

ACCLIMATION

- Acclimation period: 12 days

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

- Type and amount of food: TetraMin® Tropical Flake

- Feeding frequency: dependent upon size and temperature

- Health during acclimation (any mortality observed): Cumulative mortality must no exceed 5% in the 7-day period prior to the test.

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

40.8 - 41.3 mg/L

Test temperature:

20 - 21ºC

pH:

7.0 - 7.5

Dissolved oxygen:

62 - 100% ASV

Nominal and measured concentrations:

Nominal: Control, 31.25, 62.5, 125, 250 and 500 mg/L.

Measured concentrations in fresh media (excluding Control) at start of test: 27.2, 58.5, 119, 249 and 499 mg/L.

Measured concentrations in old media (excluding Control) after 24 h exposure: 30.7, 63.4, 124, 248 and 497 mg/L.

Measured concentrations in fresh media (excluding Control) at 48 h: 32, 64.6, 124, 241 and 490 mg/L.

Measured concentrations in old media (excluding Control) after 24 h exposure: 28.1, 59.9, 117, 232 and 492 mg/L.

Mean measured concentrations: 29.4, 61.5, 121, 242 and 494 mg/L.

Mean measured concentrations as a % of nominal: 94.1, 98.4, 96.6, 96.9 and 98.9.

Details on test conditions:

TEST SYSTEM

- Test vessel: Culture vessels

- Type: sealed

- Material: Glass

- Aeration: none

- Renewal rate of test solution (frequency): daily

- No. of organisms per vessel: 10

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

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

- Biomass loading rate: 0.38 g/L

TEST MEDIUM / WATER PARAMETERS

- Source/preparation of dilution water: Laboratory mains supply

- Chlorine: <0.1 mg/L (Total)

- Alkalinity: 14 mg/L CaCO3

- Conductivity: 128 μS/cm

- Culture medium different from test medium: no

- Intervals of water quality measurement:

OTHER TEST CONDITIONS

- Adjustment of pH: no

- Photoperiod: 16 h (light)/8 h (dark)

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :

TEST CONCENTRATIONS

- Spacing factor for test concentrations: 2.0

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 500 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

but exposure is to hydrolysis product

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

>= 500 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

but exposure is to hydrolysis product

Basis for effect:

mortality (fish)

Details on results:

- Behavioural abnormalities: At the end of the testfish exposed to the 250 mg/L nominal test concentration were showing mild toxic effects and those exposed to 500 mg/L severe toxic effects.

Reported statistics and error estimates:

There were no toxic effects at the highest test concentration and therefore statistical analysis of the results was not carried out.

Validity criteria fulfilled:

yes

Conclusions:

A 96-hour LC50 value of >500 mg/L and NOEC of ≥500 mg/L have been determined for the effects of the test substance on mortality of Brachydanio rerio based on nominal concentration of the substance. However it is likely that the test organisms were primarily exposed to the hydrolysis products of the substance.

Reference 6

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

supporting 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 Brachydanio rerio. It is likely that the test organisms were exposed predominantly to the hydrolysis products of the substance.

Description of key information

Silanol HP-X - read-across from triethoxy(methyl)silane (CAS 2031-67-6): 96-hour LC₅₀: >500 mg/l, mortality of Danio rerio (Hazleton, 1994);

Silanol HP-W and HP-Y - 96-hour LC₅₀: 130 mg/l, mortality of Oncorhynchus mykiss (read-across from CAS 82985-35-1) (HRC, 1989);

96-hour LC₅₀: >100 mg/l, mortality of Oryzias latipes (read-across from CAS 82985-35-1) (CERI, 2013);

96-hour LC₅₀: >200 mg/l, mortality of Scophthalmus maximus (read-across from CAS 13497-18-2) (Hydrotox, 2004);

Silanol HP-Z - read across from 3-aminopropyl(triethoxy)silane (CAS: 919-30-2): 96-hour LC₅₀: >934 mg/l, mortality of Brachydanio rerio (Hüls, 1994).

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Remarks:

Silanol HP-X

Effect concentration:

> 500 mg/L

Fresh water fish

Dose descriptor:

LC50

Remarks:

Silanol HP-W and HP-Y

Effect concentration:

130 mg/L

Fresh water fish

Dose descriptor:

LC50

Remarks:

Silanol HP-W and HP-Y

Effect concentration:

> 100 mg/L

Fresh water fish

Dose descriptor:

LC50

Remarks:

Silanol HP-W and HP-Y

Effect concentration:

> 200 mg/L

Fresh water fish

Dose descriptor:

LC50

Remarks:

Silanol HP-Z

Effect concentration:

> 934 mg/L

Additional information

There are no measured data for the registration substance as a whole. However according to REACH Annex XI the short-term fish study does not need to be conducted because the data requirements for this endpoint have been addressed using measured or read-across toxicity data for the constituents of the substance and their hydrolysis products.

The majority of the constituents of the substance are expected to hydrolyse rapidly, therefore the environmental aspects of chemical safety assessment are based on the hydrolysis products, which are grouped into four silanol assessment entities Silanol HP-W, Silanol HP-X, Silanol HP-Y and Silanol HP-Z. However, hydrolysis rates of some of the constituents of the substance are uncertain, therefore risk assessment has also been performed on the parent constituents which are divided into separate Blocks. The same data are used to derive PNEC for the parent Block, depending on the hydrolysis product(s) of the Block. This is discussed further in the ecotoxicological general discussion.

Data for each of the four silanol assessment entities are presented below:

Silanol HP-X: A 96-hour LC₅₀ value of >500 mg/l (nominal) has been read-across from a structural analogue, triethoxy(methyl)silane (CAS 2031-67-6) for effects of the test substance on mortality of Danio rerio (tested as Brachydanio rerio) (Hazleton, 1994). The study was conducted according to a standard guideline (EU Method C.1) and GLP. It is likely that the test organisms were exposed predominantly to the hydrolysis products of the substance, methylsilanetriol (1 mole) and ethanol (3 moles). Ethanol is not likely to have contributed to toxicity at the tested concentrations. The LC₅₀ value expressed in terms of methylsilanetriol is >500 x (94.14/178.31) = >264 mg/l.

 

Silanol HP-W and HP-Y: The short-term toxicity of Silanols HP-W and HP-Y in fish are based on weight of evidence from three read-across studies.

A 96-hour LC₅₀ value of >200 mg/l (nominal) has been read across from a structural analogue, N,N-bis(3-triethoxysilylpropyl)amine (CAS 13497-18-2) for effects on mortality of the marine fish species Scophthalmus maximus (Hydrotox, 2004). The study was conducted according using a standard method (OSPAR PARCOM protocol, similar to OECD TG 203) and GLP. It is likely that the test organisms were exposed predominantly to the hydrolysis products of the substance, bis(trihydroxysilylpropyl)amine (1 mole) and ethanol (6 moles). Ethanol is not likely to have contributed to toxicity at the tested concentrations. The LC₅₀ value expressed in terms of bis(trihydroxysilylpropyl)amine is >200 x (257.39/425.72) = >121 mg/l.

 

A 96-hour LC₅₀ value of 130 mg/l and NOEC value of 100 mg/l (nominal) have been read across from a structural analogue, 3-(trimethoxysilyl)-N-[3-(trimethoxysilyl)propyl]-1-propanamine (CAS 82985-35-1), for effects on mortality of Salmo gairdneri (new name: Oncorhynchus mykiss) (Huntingdon Research Center (HRC), 1989). The study was conducted according to a standard guideline (OECD Method 203) and GLP. It is likely that the test organisms were exposed predominantly to the hydrolysis products of the substance, bis(trihydroxysilylpropyl)amine (1 mole) and methanol (6 moles). Methanol is not likely to have contributed to toxicity at the tested concentrations. The LC₅₀ value expressed in terms of bis(trihydroxysilylpropyl)amine is 130 x (257.39/341.56) = 98.0 mg/l.

 

A 96-hour LC₅₀value of >100 mg/l (nominal) has been read across from a structural analogue 3-(trimethoxysilyl)-N-[3-(trimethoxysilyl)propyl]-1-propanamine (CAS 82985-35-1), for effects on mortality of Oryzias latipes under conditions where pH is controlled (Chemicals Evaluation and Research Institute (CERI), 2013). The LC₅₀ was 57 mg/l (nominal) under conditions where pH variation in the test media was not corrected. This value would not be representative of natural waters and so the LC₅₀ with pH correction is taken forward in the chemical safety assessment. It is likely that the test organisms were exposed predominantly to the hydrolysis products of the substance, bis(trihydroxysilylpropyl)amine (1 mole) and methanol (6 moles). Methanol is not likely to have contributed to toxicity at the tested concentrations. The LC₅₀ value expressed in terms of bis(trihydroxysilylpropyl)amine is >100 x (257.39/341.56) = >75.3 mg/l.

 

 

Silanol HP-Z: A 96-hour LC₅₀ of >934 mg/L has been read across from a structural analogue, 3-aminopropyl(triethoxy)silane (CAS 919-30-2), for effects of the test substance on mortality of Brachydanio rerio (Hüls, 1994). The study was conducted according to a standard guideline (OECD TG 203) and GLP. It is likely that the test organisms were exposed predominantly to the hydrolysis products of the substance, 3-aminopropylsilanetriol (1 mole) and ethanol (3 moles). Ethanol is not likely to have contributed to toxicity at the tested concentrations. The LC₅₀ value expressed in terms of 3-aminopropylsilanetriol is >934 x (137.21/221.37) = >579 mg/l.

 

The basis for read-across is discussed further in the Ecotoxicological information endpoint summary and in the RAAF for ecotoxicity attached in Section 13 of IUCLID and Annex 4 of the CSR.