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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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

Workers - Hazard via inhalation route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
8.82 mg/m³
Most sensitive endpoint:
repeated dose toxicity
Route of original study:
Oral
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Overall assessment factor (AF):
100
Dose descriptor starting point:
NOAEL
Value:
1 000 mg/kg bw/day
Modified dose descriptor starting point:
NOAEC
Value:
881.6 mg/m³
Explanation for the modification of the dose descriptor starting point:

The toxicity of 9-[2-(2-METHOXYETHOXY)ETHOXY]-9-[3(OXIRANYLMETHOXY)PROPYL]-2,5,8,10,13,16-HEXAOXA-9-SILAHEPTADECANE was investigated the systemic toxicity and potential adverse effects of the test item on reproduction (including offspring development) and was designed to be compatible with the requirements of the OECD Guidelines for Testing of Chemicals No. 422 “Combined Repeated Dose Toxicity Study with the Reproduction/ Developmental Toxicity Screening Test” (adopted 22 March 1996).

This study was also designed to be compatible with Commission Regulation (EC) No 440/2008 of 30 May 2008 laying down test methods pursuant to Regulation (EC) No 1907/2006 of the European Parliament and of the Council on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH). The ‘No Observed Adverse Effect Level’ (NOAEL) for systemic toxicity was therefore considered to be 1000 mg/kg bw/day.

The ‘No Observed Effect Level’ (NOEL) for reproductive toxicity was considered to be 1000 mg/kg bw/day.

Since only a sub-chronic oral toxicity study is available a route-to-route extrapolation is needed to derive the DNELs for dermal and inhalation routes. According to Chapter R.8 of REACH Guidance on information requirements and chemical safety assessment, it is proposed in the absence of route specific information on the starting route, to include a default factor of 2 in the case of oral-inhalation extrapolation. On the assumption, that in general, dermal absorption will not be higher than oral absorption, no default factor is introduced for the oral to dermal extrapolation. The REACH Guidance on information requirements and chemical safety assessment (R.8.4.2) prescribes a default factor of 1 in case of oral to dermal extrapolation. This approach will be taken forward to DNEL derivation.

AF for differences in duration of exposure:
2
Justification:
Assessment factor of two included due to extrapolation from a sub-chronic to chronic endpoint
AF for interspecies differences (allometric scaling):
2.5
Justification:
Default, to correct for differences in metabolic rate (allometric scaling) and to apply an additional factor of 2.5 for other interspecies differences, i.e. toxicokinetic differences not related to metabolic rate (small part) and toxicodynamic differences (larger part). As described in R.8.4.3.1 Assessment factors relating to the extrapolation procedure of the REACH Guidance
AF for other interspecies differences:
5
Justification:
For workers, as standard procedure for threshold effects a default assessment factor of 5 is to be used, based on the fact that this sub population does not cover the very young, the very old, and the very ill.
AF for intraspecies differences:
4
Justification:
Assuming body weight of rat 0.250 kg an allometric scaling factor of 4 is applied based on the assumed Human weight of 70 kg (as detailed in Table R8-3 of REACH Guidance on information requirements and chemical safety assessment)
Justification:
The database is considered to be of good and there is no need to include an assessment factor.
Acute/short term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
35.3 mg/m³
Most sensitive endpoint:
acute toxicity
Route of original study:
Oral
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Overall assessment factor (AF):
50
Dose descriptor starting point:
NOAEL
Value:
2 000 mg/kg bw/day
Modified dose descriptor starting point:
NOAEC
Value:
1 763.2 mg/m³
Explanation for the modification of the dose descriptor starting point:

The acute oral toxicity to the rat was assessed based on the OECD 420 Acute Oral Toxicity-Fixed dose method, Animals were dosed at 2000 mg/kg bw d and no mortalities occurred therefore the LD50 was determined to be >2000 mg/kg bw/d. Due to a lack of effects ay this dose has been used to derive DNEL values for acute/short term exposure.

An toxicity study by the inhalation is not available so a route-to-route extrapolation is needed to derive the DNELs for dermal and inhalation routes. According to Chapter R.8 of REACH Guidance on information requirements and chemical safety assessment, it is proposed in the absence of route specific information on the starting route, to include a default factor of 2 in the case of oral-inhalation extrapolation.

2000/2 (absorption rate) / 0.38 m3/kg bw = Inhalation NOAEL Rat of 2631.5 mg/m3 (8h)

 

2631.5 x 0.67 = 1763.2 mg/m3

 

Assessment factor for dose response is not required, the NOAEL from an acute study has been used for derivation of the DNEL/NOAEC. The acute laboratory endpoint is considered to reflect the most appropriate endpoint for assessing acute risk.

AF for interspecies differences (allometric scaling):
2.5
Justification:
Default, to correct for differences in metabolic rate (allometric scaling) and to apply an additional factor of 2.5 for other interspecies differences, i.e. toxicokinetic differences not related to metabolic rate (small part) and toxicodynamic differences (larger part). As described in R.8.4.3.1 Assessment factors relating to the extrapolation procedure of the REACH Guidance
AF for other interspecies differences:
4
Justification:
Assuming body weight of rat 0.250 kg an allometric scaling factor of 4 is applied based on the assumed Human weight of 70 kg (as detailed in Table R8-3 of REACH Guidance on information requirements and chemical safety assessment)
AF for intraspecies differences:
5
Justification:
For workers, as standard procedure for threshold effects a default assessment factor of 5 is to be used, based on the fact that this sub population does not cover the very young, the very old, and the very ill.
Justification:
The database is considered to be of good and there is no need to include an assessment factor.

Local effects

Long term exposure
Hazard assessment conclusion:
low hazard (no threshold derived)
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Acute/short term exposure
Hazard assessment conclusion:
low hazard (no threshold derived)
DNEL related information
DNEL derivation method:
ECHA REACH Guidance

Workers - Hazard via dermal route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
20 mg/kg bw/day
Most sensitive endpoint:
repeated dose toxicity
Route of original study:
Oral
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Overall assessment factor (AF):
100
Dose descriptor starting point:
NOAEL
Value:
1 000 mg/kg bw/day
Modified dose descriptor starting point:
NOAEL
Value:
2 000 mg/kg bw/day
Explanation for the modification of the dose descriptor starting point:

The acute dermal LD50 9-[2-(2-METHOXYETHOXY)ETHOXY]-9-[3(OXIRANYLMETHOXY)PROPYL]-2,5,8,10,13,16-HEXAOXA-9-SILAHEPTADECANE in rats of both sexes observed in a OECD 402 Acute Dermal study and determined to be greater than 2000 mg/kg, The test material has therefore practically no acute toxicity to the rat by this route of application. Skin irritation was also not observed. As a long term dermal toxicity study is not available the oral reproductive toxicity endpoint determined using a the OECD Guidelines for Testing of Chemicals No. 422 “Combined Repeated Dose Toxicity Study with the Reproduction/ Developmental Toxicity Screening test design will be used for assessment purposes. The NOAEL was determined to be 1000 mg/kg bw day, this was also the maximum tested dose.

On the assumption that, in general, dermal absorption will not be higher than oral absorption, no default factor is introduced for the oral to dermal extrapolation. The REACH Guidance on information requirements and chemical safety assessment (R.8.4.2) prescribes a default factor of 1 in case of oral to dermal extrapolation. However, based on the log Kow of <0.507 and molecular weight of the substance (500.65), the skin permeability according to Fitzpatrick et al (2004) of the substance is considered to be marginally permeable to the skin based on a calculated Log skin permeation coefficient of -7.38. Therefore, a ratio of 0.5 for oral to dermal absorption is provisonally suggested for DNEL derivation.

 

Modified dose descriptor (dermal) = 1000/0.5 (skin absorption rate for slightly permeable substance) = 2000 mg/kg bw

AF for dose response relationship:
2
Justification:
Assessment factor of two included due to extrapolation from a sub-chronic to chronic endpoint
AF for differences in duration of exposure:
2.5
Justification:
Default, to correct for differences in metabolic rate (allometric scaling) and to apply an additional factor of 2.5 for other interspecies differences, i.e. toxicokinetic differences not related to metabolic rate (small part) and toxicodynamic differences (larger part). As described in R.8.4.3.1 Assessment factors relating to the extrapolation procedure of the REACH Guidance
AF for interspecies differences (allometric scaling):
4
Justification:
Assuming body weight of rat 0.250 kg an allometric scaling factor of 4 is applied based on the assumed Human weight of 70 kg (as detailed in Table R8-3 of REACH Guidance on information requirements and chemical safety assessment)
AF for other interspecies differences:
5
Justification:
For workers, as standard procedure for threshold effects a default assessment factor of 5 is to be used, based on the fact that this sub population does not cover the very young, the very old, and the very ill.
Justification:
The database is considered to be of good and there is no need to include an assessment factor.
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information
Explanation for the modification of the dose descriptor starting point:

The acute dermal LD50 9-[2-(2-METHOXYETHOXY)ETHOXY]-9-[3(OXIRANYLMETHOXY)PROPYL]-2,5,8,10,13,16-HEXAOXA-9-SILAHEPTADECANE in rats of both sexes observed in an OECD 402 Acute Dermal study and determined to be greater than 2000 mg/kg, The test material has therefore practically no acute toxicity to the rat by this route of application. Skin irritation was also not observed in Dermal irritation, Episkin irritation, Epiderm corrrosion studies.

Local effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified

Workers - Hazard for the eyes

Local effects

Hazard assessment conclusion:
no hazard identified

Additional information - workers

According to the REACH Guidance on information requirements and chemical safety assessment, a leading DN(M)EL needs to be derived for every relevant human population and every relevant route, duration and frequency of exposure, if feasible. 

 

Short-term toxicity:

The acute oral toxicity to the rat was assessed based on the OECD 420 Acute Oral Toxicity-Fixed dose method, Animals were dosed at 2000 mg/kg bw d and no mortalities occurred therefore the LD50 was determined to be >2000 mg/kg bw/d. Due to a lack of effects ay this dose has been used to derive DNEL values for acute/short term exposure.

 

The acute dermal LD50 9-[2-(2-METHOXYETHOXY)ETHOXY]-9-[3(OXIRANYLMETHOXY)PROPYL]-2,5,8,10,13,16-HEXAOXA-9-SILAHEPTADECANE in rats of both sexes observed in anOECD 402 Acute Dermal study and determined to be greater than 2000 mg/kg, The test material has therefore practically no acute toxicity to the rat by this route of application. Skin irritation was also not observed in Dermal irritation, Episkin irritation, Epiderm corrrosion studies and sensitization was not apparent in an LLNA study.

No particular hazards were identified

 

Long-term toxicity:

The toxicity of 9-[2-(2-METHOXYETHOXY)ETHOXY]-9-[3(OXIRANYLMETHOXY)PROPYL]-2,5,8,10,13,16-HEXAOXA-9-SILAHEPTADECANE was investigated the systemic toxicity and potential adverse effects of the test item on reproduction (including offspring development) and was designed to be compatible with the requirements of the OECD Guidelines for Testing of Chemicals No. 422 “Combined Repeated Dose Toxicity Study with the Reproduction/ Developmental Toxicity Screening Test” (adopted 22 March 1996). This study was also designed to be compatible with Commission Regulation (EC) No 440/2008 of 30 May 2008 laying down test methods pursuant to Regulation (EC) No 1907/2006 of the European Parliament and of the Council on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH). The ‘No Observed Adverse Effect Level’ (NOAEL) for systemic toxicity was therefore considered to be 1000 mg/kg bw/day. The ‘No Observed Effect Level’ (NOEL) for reproductive toxicity was considered to be 1000 mg/kg bw/day.

Since only a sub-chronic toxicity study is available a route-to-route extrapolation is needed to derive the DNELs for dermal and inhalation route. According to Chapter R.8 of REACH Guidance on information requirements and chemical safety assessment, it is

proposed in the absence of route-specific information on the starting route, to include a default factor of 2 in the case of oral-to-inhalation extrapolation. On the assumption that, in general, dermal absorption will not be higher than oral absorption, The REACH Guidance on information requirements and chemical safety assessment (R.8.4.2) prescribes a default factor of 1 in case of oral to dermal extrapolation. However, based on the log Kow of <0.507and molecular weight of the substance (500.65), the skin permeability according to Fitzpatrick et al (2004) of the substance is considered to be marginally permeable to the skin. Therefore, a ratio of 0.5 for oral to dermal absorption is provisonally suggested for DNEL derivation

General Population - Hazard via inhalation route

Systemic effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information
Explanation for the modification of the dose descriptor starting point:

The substance is not intended to be marketed for consumer use.

Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information
Explanation for the modification of the dose descriptor starting point:

The substance is not intended to be marketed for consumer use.

Local effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

General Population - Hazard via dermal route

Systemic effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information
Explanation for the modification of the dose descriptor starting point:

The substance is not intended to be marketed for consumer use.

Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information
Explanation for the modification of the dose descriptor starting point:

The substance is not intended to be marketed for consumer use.

Local effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified

General Population - Hazard via oral route

Systemic effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information
Explanation for the modification of the dose descriptor starting point:

The substance is not intended to be marketed for consumer use.

Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information
Explanation for the modification of the dose descriptor starting point:

The substance is not intended to be marketed for consumer use.

General Population - Hazard for the eyes

Local effects

Hazard assessment conclusion:
no hazard identified

Additional information - General Population

The substance is not intended to be marketed for consumer use.