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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Administrative data

Key value for chemical safety assessment

Effects on fertility

Description of key information

A GLP-compliant 90-day repeated dose toxicity study in rats via the inhalation route following OECD 413 is proposed for the registered substance according to Annex IX, Column 1, Section 8.6.2. When available, the data from this study will be assessed in order to established whether there is a need to include a testing proposal for the extended one-generation reproductive toxicity study (as per Column 1 of REACH Annex IX, Section 8.7.3).


In the interim, read-across to the structural analogue substances triethoxy(isobutyl)silane (CAS 17980-47-1) and trimethoxy(methyl)silane (CAS 1185-55-3) has been used to assess the reproductive toxicity potential of trimethoxy(propyl)silane.


Key (OECD 415 in rats, oral): NOAEL (reproductive toxicity) >= 1000 mg/kg bw/day (CAS 17980-47-1)


Supporting (OECD 422 in rats, oral): NOAEL (reproductive toxicity) >= 1000 mg/kg bw/day (CAS 1185-55-3)

Link to relevant study records

Referenceopen allclose all

Endpoint:
extended one-generation reproductive toxicity - basic test design (Cohorts 1A, and 1B without extension)
Data waiving:
study scientifically not necessary / other information available
Justification for data waiving:
other:
Reason / purpose for cross-reference:
data waiving: supporting information
Reproductive effects observed:
not specified
Endpoint:
one-generation reproductive toxicity
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Justification for type of information:
See attached interim read-across justification.
Reason / purpose for cross-reference:
read-across source
Dose descriptor:
NOAEL
Effect level:
>= 1 000 mg/kg bw/day (actual dose received)
Based on:
test mat.
Sex:
male/female
Basis for effect level:
other: no treatment-related adverse effects observed at any dose.
Dose descriptor:
NOAEL
Generation:
F1
Effect level:
>= 1 000 mg/kg bw/day (actual dose received)
Based on:
test mat.
Sex:
male/female
Basis for effect level:
other: no adverse effects on reproductive parameters at any dose.
Reproductive effects observed:
no
Conclusions:
In a rat oral one-generation reproductive toxicity study conducted to OECD 415 and to GLP (reliability score 1) the NOAEL for parental general toxicity and for reproductive toxicity for the structural analogue substance triethoxy(isobutyl)silane (CAS 17980-47-1) was at least 1000 mg/kg bw/day, as no adverse effects were observed at any dose.
Effect on fertility: via oral route
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
NOAEL
1 000 mg/kg bw/day
Study duration:
subchronic
Species:
rat
Quality of whole database:
The available information comprises an adequate and reliable study, and is thus sufficient to fulfil the standard information requirements set out in Annex VIII-IX, 8.6, of Regulation (EC) No 1907/2006.
Effect on fertility: via inhalation route
Endpoint conclusion:
no study available
Effect on fertility: via dermal route
Endpoint conclusion:
no study available
Additional information

A GLP-compliant 90-day repeated dose toxicity study in rats via the inhalation route following OECD 413 is proposed for the registered substance according to Annex IX, Column 1, Section 8.6.2. When available, the data from this study will be assessed in order to establish whether there is a need to include a testing proposal for the extended one-generation reproductive toxicity study (as per Column 1 of REACH Annex IX, Section 8.7.3).


In the interim, read-across to the structural analogue substances triethoxy(isobutyl)silane (CAS 17980-47-1) and trimethoxy(methyl)silane (CAS 1185-55-3) has been used to assess the reproductive toxicity potential of trimethoxy(propyl)silane (see the interim analogue justification in the respective target endpoint study record).


 


Key Study (CAS 17980-47-1):


A reliable one-generation reproductive study conducted in compliance with GLP and according to OECD 415 with the structural analogue substance triethoxy(isobutyl)silane (CAS 17980-47-1) is available. The NOAEL for reproductive toxicity was at least 1000 mg/kg bw/day, as no adverse effects were observed at any dose (Safepharm Laboratories Ltd, 1992).


At 1000 mg/kg bw/day, a reduction in the total number of pregnancies was observed but without statistically significant differences in the mating and pregnancy indices. This finding was considered not to be a treatment-related effect upon fertility. The pre-coital intervals were comparable for all groups with the majority of matings occurring within four days of pairing. The pregnancy and mating indices for all groups were within acceptable limits. The gestation length was comparable with no statistically significant differences between treated groups and controls.


Live birth index and live litter size, before and after litter standardization were comparable for all groups throughout lactation up to weaning. There were no effects upon litter sex ratios. Statistical evaluation showed no significant differences for the treated groups compared to controls.


At 1000 mg/kg bw/day there was a slight but statistically significant difference in group mean litter weights (p<0.05) and individual offspring bodyweight (p<0.05) on Day 7 post-partum. The difference in group mean litter weights and individual offspring bodyweight remained statistically significant (litter weights p>0.05, individual weights p>0.01) on Day 14 and 21 post-partum but the increase in weight gain, relative to the group starting weight for each period of measurement, was comparable for each group. Therefore, this was not considered toxicologically significant.


There were no differences in the time of appearance of the landmarks of offspring development at any dose. Nor were there any effects observed in the reflexology tests.


 


Supporting Study (CAS 1185-55-3):


In the Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test with the structural analogue substance trimethoxy(methyl)silane (CAS 1185-55-3), conducted according to OECD Test Guideline 422 and in compliance with GLP, the NOAEL for reproductive toxicity was concluded to be at least 1000 mg/kg bw/day based on no adverse effects (Dow Corning Corporation, 2005).


There were no treatment-related effects apparent for any of the reproductive endpoints. All females bred successfully and delivered live litters. Litter sizes were comparable for all groups. Differences in group mean values for the treated groups relative to the control group were small and none were found to be statistically significant.

Effects on developmental toxicity

Description of key information

In order to fulfil the standard information requirements, a GLP-compliant pre-natal developmental toxicity study in rats via the oral route following OECD 414 is proposed for the registration substance according to Annex IX, Column 1, Section 8.7.2.


In the interim, data on the structural analogue substances triethoxy(isobutyl)silane (CAS 17980-47-1) and trimethoxy(methyl)silane (CAS 1185-55-3) have been used to assess the developmental toxicity potential of trimethoxy(propyl)silane.


Key (OECD 414 in rats, oral): NOAEL (developmental toxicity) >= 1000 mg/kg bw/day (CAS 17980-47-1)


Supporting (OECD 422 in rats, oral): NOAEL (developmental toxicity) >= 1000 mg/kg bw/day (CAS 1185-55-3)

Link to relevant study records

Referenceopen allclose all

Endpoint:
developmental toxicity
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Justification for type of information:
See attached interim read-across justification.
Reason / purpose for cross-reference:
read-across source
Dose descriptor:
NOAEL
Effect level:
>= 1 000 mg/kg bw/day (actual dose received)
Based on:
test mat.
Basis for effect level:
other: developmental toxicity
Dose descriptor:
NOAEL
Effect level:
>= 1 000 mg/kg bw/day (actual dose received)
Based on:
test mat.
Sex:
male/female
Basis for effect level:
other: developmental toxicity
Developmental effects observed:
no
Conclusions:
In an oral developmental toxicity study conducted to OECD 414 and to GLP (reliability score 1) there were no effects on rat fetal development and the NOAEL was therefore at least 1000 mg/kg bw/day (the highest dose tested) for the structural analogue substance triethoxy(isobutyl)silane.
Endpoint:
developmental toxicity
Type of information:
experimental study planned
Remarks:
The test will be conducted after a decision on the requirement to carry out the proposed test has been taken according to the procedure laid down in Regulation (EC) 1907/2006 and a deadline to submit the information required has been set by the Agency.
Study period:
The test will be conducted after a decision on the requirement to carry out the proposed test has been taken according to the procedure laid down in Regulation (EC) No. 1907/2006 and a deadline to submit the information required has been set by the Agency
Justification for type of information:
TESTING PROPOSAL ON VERTEBRATE ANIMALS
NON-CONFIDENTIAL NAME OF SUBSTANCE:
- Name of the substance on which testing is proposed to be carried out: Trimethoxy(propyl)silane (CAS 1067-25-0)
CONSIDERATIONS THAT THE GENERAL ADAPTATION POSSIBILITIES OF ANNEX XI OF THE REACH REGULATION ARE NOT ADEQUATE TO GENERATE THE NECESSARY INFORMATION:
- Available GLP studies: There are no GLP-compliant studies available on developmental toxicity with the registered substance.
- Available non-GLP studies: There are no non-GLP-compliant studies available on developmental toxicity with the registered substance.
- Historical human data: Not available.
- QSAR: Q(SAR) methods are not applicable to assess the full scope of developmental toxicity.
- In vitro methods: No validated or regulatory accepted alternative methods are available for replacing animal testing with respect to developmental toxicity.
- Weight of evidence: There is no information (QSAR, in vitro data, developmental toxicity or fertility data) available which is suitable to assess developmental toxicity in a weight of evidence approach.
- Grouping and read-across: Developmental toxicity data on suitable structural analogue substances is not available.
CONSIDERATIONS THAT THE SPECIFIC ADAPTATION POSSIBILITIES OF ANNEXES VI TO X (AND COLUMN 2 THEREOF) OF THE REACH REGULATION ARE NOT ADEQUATE TO GENERATE THE NECESSARY INFORMATION:
- In order to fulfil the standard information requirements, a GLP-compliant developmental toxicity study in rats via the oral route following OECD guideline 414 is proposed according to Annex IX, Column 1, Section 8.7.2.
- Column 2 adaptation possibilities at the Annex IX, Section 8.7. level were considered and do not apply: Trimethoxy(propyl)silane is not known to be a genotoxic carcinogen, meeting the criteria for classification both in the hazard class germ cell mutagenicity (category 1A or 1B or 2) and carcinogenicity (category 1A or 1B). The substance is not known to be a germ cell mutagen, meeting the criteria for classification in the hazard class germ cell mutagenicity (category 1A or 1B). The substance is not known to cause developmental toxicity, meeting the criteria for classification in the hazard class reproductive toxicity (category 1A or 1B: May damage the unborn child (H360D)). The substance is not of low toxicological activity and it could not be proven from toxicokinetic data that no systemic absorption occurs via relevant routes of exposure; there is evidence of absorption and toxicity.
FURTHER INFORMATION ON TESTING PROPOSAL IN ADDITION TO INFORMATION PROVIDED IN THE MATERIALS AND METHODS SECTION:
- Details on study design / methodology proposed: A developmental toxicity study in rats via the oral route following OECD guideline 414 will be conducted with trimethoxy(propyl)silane.
Qualifier:
according to guideline
Guideline:
OECD Guideline 414 (Prenatal Developmental Toxicity Study)
Deviations:
no
Principles of method if other than guideline:
There are no data available on the developmental toxicity/teratogenicity of trimethoxy(propyl)silane.
In order to fulfil the standard information requirements, a GLP-compliant pre-natal developmental toxicity study in rats via the oral route following OECD guideline 414 is proposed according to Annex IX, Column 1, Section 8.7.2.
Species:
rat
Route of administration:
oral: gavage
Effect on developmental toxicity: via oral route
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
NOAEL
1 000 mg/kg bw/day
Study duration:
subacute
Species:
rat
Quality of whole database:
The available information comprises an adequate and reliable study, and is thus sufficient to fulfil the standard information requirements set out in Annex VIII-IX, 8.6, of Regulation (EC) No 1907/2006.
Effect on developmental toxicity: via inhalation route
Endpoint conclusion:
no study available
Effect on developmental toxicity: via dermal route
Endpoint conclusion:
no study available

Toxicity to reproduction: other studies

Additional information

In order to fulfil the standard information requirements, a GLP-compliant pre-natal developmental toxicity study in rats via the oral route following OECD 414 is proposed for the registration substance according to Annex IX, Column 1, Section 8.7.2.


In the interim, data on the structural analogue substances triethoxy(isobutyl)silane (CAS 17980-47-1) and trimethoxy(methyl)silane (CAS 1185-55-3) have been used to assess the developmental toxicity potential of trimethoxy(propyl)silane (see the interim analogue justification in the respective target endpoint study record).


 


Key Study (CAS 17980-47-1):


A key reliable developmental study with the structural analogue substance triethoxy(isobutyl)silane is available. This oral developmental toxicity study was conducted according to OECD 414 and to GLP (Safepharm Laboratories Ltd., 1991). There were no effects on rat fetal development and the NOAEL was therefore at least 1000 mg/kg bw/day (the highest dose tested).


 


Supporting Study (CAS 1185-55-3):


In a Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test with the structural analogue substance trimethoxy(methyl)silane, conducted according to OECD 422 and in compliance with GLP, the NOAEL for developmental toxicity was concluded to be at least 1000 mg/kg bw/day based on an absence of adverse effects up to the highest dose level tested (Dow Corning Corporation, 2005).

Justification for classification or non-classification

The available data on toxicity to reproduction of the structural analogue substances, trimethoxy(methyl)silane (CAS 1185-55-3) and triethoxy(isobutyl)silane (CAS 17980-47-1), do not meet the criteria for classification according to Regulation (EC) No. 1272/2008, and are therefore conclusive but not sufficient for classification of the registered substance.


No information is available on effects via lactation.

Additional information