Ethanol, 2,2'-oxybis-, reaction products with 3-(triethoxysilyl)-1-propanamine

Endpoint summary

Description of key information

Skin Irritation

REACH_not corrosive | Epiderm | OECD 431 | #key study##Analogy (152261 -44 -4)#

REACH_not irritating | Epiderm | OECD 439 | #key study##Analogy (152261 -44 -4)#

Eye Irritation

REACH_no prediction | BCOP | OECD 437 | #key study##Analogy (152261 -44 -4)#

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Reference 1

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

2018-01-16 to 2018-01-18

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Analogy to Ethanol, 2,2'-[1,2-ethanediylbis(oxy)]bis-, RP with 3-(triethoxysilyl)-1-propanamine, CAS 152261-44-4:

Ethanol, 2,2'-oxybis-, reaction products with 3-(triethoxysilyl)-1-propanamine (CAS 152261-43-3) is a complex reaction mixture (UVCB) of 3-aminopropyltriethoxysilane (CAS 919-30-2) and diethylene glycol (CAS ‎111-46-69). Diethylene glycol is the main component besides smaller amounts of ethanol (CAS 64-17-5). No free 3-aminopropyltriethoxysilane is detectable, because it is covalently bound to the oligomeric structures of the reaction product.

A comparable reaction mixture namely Ethanol, 2,2'-[1,2-ethanediylbis(oxy)]bis-, reaction products with 3-(triethoxysilyl)-1-propanamine (CAS 152261-44-4) was submitted to acute toxicity testing. The tested reaction product does contain triethylene glycol instead of diethylene glycol as main component and ethanol. The data on Ethanol, 2,2'-[1,2-ethanediylbis(oxy)]bis-, reaction products with 3-(triethoxysilyl)-1-propanamine were used for evaluation of the reaction product with diethylene glycol.

Ethanol, 2,2'-oxybis-, reaction products with 3-(triethoxysilyl)-1-propanamine are unstable upon contact with moisture. The product undergoes further condensation reactions that form highly polymerized poly silicic acids while liberating the diethylene glycol, that was initially bound to the oligomeric structures. The underlying chemistry is commonly known as sol-gel reaction. The poly silicic acid moieties are not stable and prone to further condensation generating water insoluble, resinous polymers. The molecular weight of the resulting polymers is predicted to be over 1000. These polymers are stable and not bioavailable.

For the above mentioned reasons the toxicological profile of Ethanol, 2,2'-oxybis-, reaction products with 3-(triethoxysilyl)-1-propanamine will be mainly determined by the solvents, which are very well investigated.

Diethylene glycol and triethylene glycol belong to the group of ethylene glycols represented by the generic molecular structure HO(CH2CH2O)nH, where n = 2-3. Diethylene glycol and triethylene glycol are closely related in structure, both substances possess two terminal hydroxy groups and differ from each other only in the number of one oxyethylene unit. Both substances are total miscibility with water and exhibit a comparable toxicological profile as well as metabolic fate (OECD SIDS Initial Assessment Profile, ethylene glycols, 2004).

Therefore the acute data generated with Ethanol, 2,2'-[1,2-ethanediylbis(oxy)]bis-, reaction products with 3-(triethoxysilyl)-1-propanamine can be applied to adequately address acute toxicity of Ethanol, 2,2'-oxybis-, reaction products with 3-(triethoxysilyl)-1-propanamine.

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

OECD Guideline 431 (In Vitro Skin Corrosion: Reconstructed Human Epidermis (RHE) Test Method)

Qualifier:

according to guideline

Guideline:

other: Council Regulation 440/2008, Method B.40 BIS: “In Vitro Skin Corrosion: Human Skin Model Test”, May 30, 2008

Qualifier:

according to guideline

Guideline:

other: MatTek Corporation Protocol for: In Vitro EpiDermTM Skin Corrosion Test (EPI-200-SCT) For use with MatTek Corporation’s Reconstructed Human Epidermal Model EpiDerm

Version / remarks:

Version 07/11/2014

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

60 min. treatment

Value:

97.5

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Remarks:

100.0

Positive controls validity:

valid

Remarks:

1.5

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

3 min. treatment

Value:

106.8

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Remarks:

100.0

Positive controls validity:

valid

Remarks:

5.2

Interpretation of results:

other: not corrosive

Conclusions:

In this study under the given conditions the test item showed no corrosive effects.
The test item is classified as “non-corrosive“.

Reference 2

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

2018-02-21 to 2018-02-23

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Analogy to Ethanol, 2,2'-[1,2-ethanediylbis(oxy)]bis-, RP with 3-(triethoxysilyl)-1-propanamine, CAS 152261-44-4:

Ethanol, 2,2'-oxybis-, reaction products with 3-(triethoxysilyl)-1-propanamine (CAS 152261-43-3) is a complex reaction mixture (UVCB) of 3-aminopropyltriethoxysilane (CAS 919-30-2) and diethylene glycol (CAS ‎111-46-69). Diethylene glycol is the main component besides smaller amounts of ethanol (CAS 64-17-5). No free 3-aminopropyltriethoxysilane is detectable, because it is covalently bound to the oligomeric structures of the reaction product.

A comparable reaction mixture namely Ethanol, 2,2'-[1,2-ethanediylbis(oxy)]bis-, reaction products with 3-(triethoxysilyl)-1-propanamine (CAS 152261-44-4) was submitted to acute toxicity testing. The tested reaction product does contain triethylene glycol instead of diethylene glycol as main component and ethanol. The data on Ethanol, 2,2'-[1,2-ethanediylbis(oxy)]bis-, reaction products with 3-(triethoxysilyl)-1-propanamine were used for evaluation of the reaction product with diethylene glycol.

Ethanol, 2,2'-oxybis-, reaction products with 3-(triethoxysilyl)-1-propanamine are unstable upon contact with moisture. The product undergoes further condensation reactions that form highly polymerized poly silicic acids while liberating the diethylene glycol, that was initially bound to the oligomeric structures. The underlying chemistry is commonly known as sol-gel reaction. The poly silicic acid moieties are not stable and prone to further condensation generating water insoluble, resinous polymers. The molecular weight of the resulting polymers is predicted to be over 1000. These polymers are stable and not bioavailable.

For the above mentioned reasons the toxicological profile of Ethanol, 2,2'-oxybis-, reaction products with 3-(triethoxysilyl)-1-propanamine will be mainly determined by the solvents, which are very well investigated.

Diethylene glycol and triethylene glycol belong to the group of ethylene glycols represented by the generic molecular structure HO(CH2CH2O)nH, where n = 2-3. Diethylene glycol and triethylene glycol are closely related in structure, both substances possess two terminal hydroxy groups and differ from each other only in the number of one oxyethylene unit. Both substances are total miscibility with water and exhibit a comparable toxicological profile as well as metabolic fate (OECD SIDS Initial Assessment Profile, ethylene glycols, 2004).

Therefore the acute data generated with Ethanol, 2,2'-[1,2-ethanediylbis(oxy)]bis-, reaction products with 3-(triethoxysilyl)-1-propanamine can be applied to adequately address acute toxicity of Ethanol, 2,2'-oxybis-, reaction products with 3-(triethoxysilyl)-1-propanamine.

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

OECD Guideline 439 (In Vitro Skin Irritation: Reconstructed Human Epidermis Test Method)

Qualifier:

according to guideline

Guideline:

other: Commission Regulation (EC) No. 640/2012, L 193, Part B.46. “In vitro Skin Irritation: Reconstructed Human Epidermis Test Method” 06-Jul-2012

Qualifier:

according to guideline

Guideline:

other: MatTek Corporation Protocol for: In Vitro EpiDermTM Skin Irritation Test (EPI-200-SIT) For use with MatTek Corporation’s Reconstructed Human Epidermal Model EpiDerm (EPI-200-SIT)

Version / remarks:

Version 07-Nov-2014

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

Test item

Value:

94.9

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Remarks:

100.0

Positive controls validity:

valid

Remarks:

3.0

Interpretation of results:

GHS criteria not met

Conclusions:

In this study under the given conditions the test item showed no irritant effects.
The test item is therefore classified as “non-irritant” in accordance with UN GHS “No Category”.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records

Reference

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

2018-02-13 to 2018-05-23

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Analogy to Ethanol, 2,2'-[1,2-ethanediylbis(oxy)]bis-, RP with 3-(triethoxysilyl)-1-propanamine, CAS 152261-44-4:

Ethanol, 2,2'-oxybis-, reaction products with 3-(triethoxysilyl)-1-propanamine (CAS 152261-43-3) is a complex reaction mixture (UVCB) of 3-aminopropyltriethoxysilane (CAS 919-30-2) and diethylene glycol (CAS ‎111-46-69). Diethylene glycol is the main component besides smaller amounts of ethanol (CAS 64-17-5). No free 3-aminopropyltriethoxysilane is detectable, because it is covalently bound to the oligomeric structures of the reaction product.

A comparable reaction mixture namely Ethanol, 2,2'-[1,2-ethanediylbis(oxy)]bis-, reaction products with 3-(triethoxysilyl)-1-propanamine (CAS 152261-44-4) was submitted to acute toxicity testing. The tested reaction product does contain triethylene glycol instead of diethylene glycol as main component and ethanol. The data on Ethanol, 2,2'-[1,2-ethanediylbis(oxy)]bis-, reaction products with 3-(triethoxysilyl)-1-propanamine were used for evaluation of the reaction product with diethylene glycol.

Ethanol, 2,2'-oxybis-, reaction products with 3-(triethoxysilyl)-1-propanamine are unstable upon contact with moisture. The product undergoes further condensation reactions that form highly polymerized poly silicic acids while liberating the diethylene glycol, that was initially bound to the oligomeric structures. The underlying chemistry is commonly known as sol-gel reaction. The poly silicic acid moieties are not stable and prone to further condensation generating water insoluble, resinous polymers. The molecular weight of the resulting polymers is predicted to be over 1000. These polymers are stable and not bioavailable.

For the above mentioned reasons the toxicological profile of Ethanol, 2,2'-oxybis-, reaction products with 3-(triethoxysilyl)-1-propanamine will be mainly determined by the solvents, which are very well investigated.

Diethylene glycol and triethylene glycol belong to the group of ethylene glycols represented by the generic molecular structure HO(CH2CH2O)nH, where n = 2-3. Diethylene glycol and triethylene glycol are closely related in structure, both substances possess two terminal hydroxy groups and differ from each other only in the number of one oxyethylene unit. Both substances are total miscibility with water and exhibit a comparable toxicological profile as well as metabolic fate (OECD SIDS Initial Assessment Profile, ethylene glycols, 2004).

Therefore the acute data generated with Ethanol, 2,2'-[1,2-ethanediylbis(oxy)]bis-, reaction products with 3-(triethoxysilyl)-1-propanamine can be applied to adequately address acute toxicity of Ethanol, 2,2'-oxybis-, reaction products with 3-(triethoxysilyl)-1-propanamine.

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

other: OECD Guideline for the Testing of Chemicals, no. 437 (adopted: 09 October 2017)

Species:

other: bovine cornea

Strain:

not specified

Vehicle:

unchanged (no vehicle)

Irritation parameter:

in vitro irritation score

Remarks:

mean

Run / experiment:

test item

Value:

46.32

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Remarks:

0.81

Positive controls validity:

valid

Remarks:

63.38

Other effects / acceptance of results:

No prediction can be made regarding the classification of the test substance according to the evaluation criteria.

Interpretation of results:

other: An IVIS of 46.32 was determined which is close to the cut-off for classification as severely eye damaging of 55.1. Due to the severe corneal effects observed, the test substance is classified as severely damaging to eyes.

Conclusions:

No prediction can be made regarding the classification of the test substance according to the evaluation criteria.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irreversible damage)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

Eye Irritation

Ethanol, 2,2'-[1,2-ethanediylbis(oxy)]bis-, reaction products with 3-(triethoxysilyl)-1-propanamine (CAS 152261-44-4) is a reaction mixture of 3-aminopropyltriethoxysilane (CAS 919-30-2) and triethylene glycol (CAS 112-27-6). Triethylene glycol is the main component besides smaller amounts of ethanol (CAS 64-17-5). The eye irritancy potential of the reaction mixture with triethylene glycol was investigated in the bovine corneal opacity and permeability assay.

These data were used for evaluation of Ethanol, 2,2'-oxybis-, reaction products with 3-(triethoxysilyl)-1-propanamine (CAS 152261-43-3), which is based on diethylene glycol (CAS ‎111-46-6) instead of triethylene glycol. Both, diethylene glycol and triethylene glycol possess a comparable eye irritation potential (SIDS Initial Assessment Profile, ethylene glycols, 2004). Therefore the results obtained for the reaction mixture with triethylene glycol can also be used for classification of Ethanol, 2,2'-oxybis-, reaction products with 3-(triethoxysilyl)-1-propanamine.

All three corneas showed opacity of the tissue. Furthermore, the permeability score of the tissues was also significantly increased. An IVIS of 46.32 was determined which is close to the cut-off for classification as severely eye damaging of 55.1.

Due to the severe corneal effects observed, Ethanol, 2,2'-oxybis-, reaction products with 3-(triethoxysilyl)-1-propanamine is classified as severely damaging to eyes.

 

Skin Irritation

Ethanol, 2,2'-[1,2-ethanediylbis(oxy)]bis-, reaction products with 3-(triethoxysilyl)-1-propanamine (CAS 152261-44-4) is a close analogue to Ethanol, 2,2'-oxybis-, reaction products with 3-(triethoxysilyl)-1-propanamine (CAS 152261-43-3) and was submitted to an OECD 431 and OECD 439 study. Ethanol, 2,2'-[1,2-ethanediylbis(oxy)]bis-, reaction products with 3-(triethoxysilyl)-1-propanamine does not require classification as corrosive or irritant to skin.

The tested structural analogue Ethanol, 2,2'-[1,2-ethanediylbis(oxy)]bis-, reaction products with 3-(triethoxysilyl)-1-propanamine is based on triethylene glycol (CAS 112-27-6) instead of diethylene glycol (CAS‎ 111-46-6). Triethylene glycol and diethylene glycol, respectively, are the main components of both reaction products apart from smaller amounts of ethanol (CAS 64-17-5). The reaction products do not contain free 3-aminopropyltriethoxysilane (CAS 919-30-2). Both, diethylene glycol and triethylene glycol possess a comparable skin irritation potential (SIDS Initial Assessment Profile, ethylene glycols, 2004). Therefore, the results obtained for the reaction mixture with triethylene glycol can also be used for classification of Ethanol, 2,2'-oxybis-, reaction products with 3-(triethoxysilyl)-1-propanamine.

Similar to the tested reaction mixture, the reaction product with diethylene glycol is unstable upon contact with moisture. lt undergoes further condensation reactions that form highly polymerized poly silicic acids while liberating the diethylene glycol, that was initially bound to the oligomeric structures. The underlying chemistry is commonly known as sol-gel reaction. The poly silicic acid moieties are not stable and prone to further condensation generating waterinsoluble, resinous polymers. The molecular weight of the resulting polymers is predicted to be over 1000. These polymers are stable and not bioavailable.

Because 3-aminopropyltriethoxysilane is completely consumed into the polymer matrix the toxicological profile of the reaction product with diethylene glycol will be mainly determined by diethylene glycol and to a lesser extent by ethanol.

Neither diethylene glycol nor ethanol are skin irritants, both solvents are not classified as irritating to skin in accordance with Annex VI to Regulation (EC) No 1272/2008. However, it was demonstrated that 3-aminopropyltriethoxysilane is corrosive to skin (OECD SIDS Initial Assessment Report, 3-aminopropyltriethoxysilane, 2003).

Ethanol, 2,2'-oxybis-, reaction products with 3-(triethoxysilyl)-1-propanamine does not contain free 3-aminopropyltriethoxysilane, which is the only component with a skin irritation/corrosion potential. 3-Aminopropyltriethoxysilane is not freely available because it is incorporated in oligomeric structures which further polymerize. The contained solvents diethylene glycol and ethanol are not irritant to skin. Based on the compositional information and due to polymerization of Ethanol, 2,2'-oxybis-, reaction products with 3-(triethoxysilyl)-1-propanamine no irritating or corrosive properties are expected. This was confirmed by testing of an analogous reaction product in an OECD 431 and OECD 439 study. For this reason, Ethanol, 2,2'-oxybis-, reaction products with 3-(triethoxysilyl)-1-propanamine is not classified in a Weight of Evidence approach.