Registration Dossier

Administrative data

Workers - Hazard via inhalation route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
49.4 mg/m³
Most sensitive endpoint:
developmental toxicity / teratogenicity
Route of original study:
Oral
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Overall assessment factor (AF):
12.5
Modified dose descriptor starting point:
NOAEC
Value:
617 mg/m³
Explanation for the modification of the dose descriptor starting point:

The DNEL for systemic effects via the inhaled route is determined on the basis of route-to route extrapolation from the OECD 414 oral study with dimethylsilanediol (DMSD). Since HCl does not contribute to the systemic toxicity of dichloro(dimethyl)silane, it is appropriate to correct the observed NOAEL for DMSD to give the starting dose of parent material that would result in administration of 250 mg/kg of DMSD. This is done as follows: NOAEL (DMSD) = 250 mg/kg/day MW (DMSD) = 92.17 MW (dichloro(dimethyl)silane) = 129.06 NOAEL (dichloro(dimethyl)silane) = 250 mg/kg/d * 129.06/92.17 = 350 mg/kg/day  The following correction was made to the NOAEL (oral): Correction respiratory volume rat (8 hour) 1/0.38 m3/kg bw/day, Correction for respiratory volume (worker): 6.7 m3/10 m3.  Therefore the corrected NOAEC for repeated-dose systemic effects via the inhalation route is: 350 mg/kg/day*(1/0.38) *(6.7 m3/10 m3)* = 617 mg/m3.

AF for dose response relationship:
1
Justification:
Default
AF for differences in duration of exposure:
1
Justification:
Default (developmental effect, no duration AF needed)
AF for interspecies differences (allometric scaling):
1
Justification:
Default (oral rat to inhaled human)
AF for other interspecies differences:
2.5
Justification:
Default
AF for intraspecies differences:
5
Justification:
Default
AF for the quality of the whole database:
1
Justification:
Default (guideline study)
AF for remaining uncertainties:
1
Justification:
Default (no remaining uncertainties)
Acute/short term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
49.4 mg/m³
Most sensitive endpoint:
developmental toxicity / teratogenicity
Route of original study:
Oral
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Overall assessment factor (AF):
12.5
DNEL extrapolated from long term DNEL

Local effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
14.2 mg/m³
Most sensitive endpoint:
irritation (respiratory tract)
DNEL related information
DNEL derivation method:
other: EU OEL
Overall assessment factor (AF):
1
Dose descriptor:
other: 14.2 mg/m3
Acute/short term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
14.2 mg/m³
Most sensitive endpoint:
irritation (respiratory tract)
DNEL related information
DNEL derivation method:
other: EU OEL
Overall assessment factor (AF):
1
DNEL extrapolated from long term DNEL

Workers - Hazard via dermal route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
7 mg/kg bw/day
Most sensitive endpoint:
developmental toxicity / teratogenicity
Route of original study:
Oral
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Overall assessment factor (AF):
50
Modified dose descriptor starting point:
NOAEL
Value:
350 mg/kg bw/day
Explanation for the modification of the dose descriptor starting point:

The DNEL for systemic effects via the dermal route is determined on the basis of route-to route extrapolation from the OECD 414 oral study with dimethylsilanediol (DMSD). Since HCl does not contribute to the systemic toxicity of dichloro(dimethyl)silane, it is appropriate to correct the observed NOAEL for DMSD to give the starting dose of parent material that would result in administration of 250 mg/kg of DMSD. This is done as follows: NOAEL (DMSD) = 250 mg/kg/day MW (DMSD) = 92.17 MW (dichloro(dimethyl)silane) = 129.06 NOAEL (dichloro(dimethyl)silane) = 250 mg/kg/d * 129.06/92.17 = 350 mg/kg/day

AF for dose response relationship:
1
Justification:
Default
AF for differences in duration of exposure:
1
Justification:
Default (developmental effect, no duration AF needed)
AF for interspecies differences (allometric scaling):
4
Justification:
Default (oral rat to dermal human)
AF for other interspecies differences:
2.5
Justification:
Default
AF for intraspecies differences:
5
Justification:
Default
AF for the quality of the whole database:
1
Justification:
Default (guideline study)
AF for remaining uncertainties:
1
Justification:
Default (guideline study)
Acute/short term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
7 mg/kg bw/day
Most sensitive endpoint:
developmental toxicity / teratogenicity
Route of original study:
Oral
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Overall assessment factor (AF):
50
DNEL extrapolated from long term DNEL

Local effects

Long term exposure
Hazard assessment conclusion:
medium hazard (no threshold derived)
Most sensitive endpoint:
skin irritation/corrosion
Acute/short term exposure
Hazard assessment conclusion:
medium hazard (no threshold derived)
Most sensitive endpoint:
skin irritation/corrosion

Workers - Hazard for the eyes

Local effects

Hazard assessment conclusion:
medium hazard (no threshold derived)

Additional information - workers

General Population - Hazard via inhalation route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
8.7 mg/m³
Most sensitive endpoint:
developmental toxicity / teratogenicity
Route of original study:
Oral
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Overall assessment factor (AF):
25
Modified dose descriptor starting point:
NOAEC
Value:
217 mg/m³
Explanation for the modification of the dose descriptor starting point:

The DNEL for systemic effects via the inhaled route is determined on the basis of route-to route extrapolation from the OECD 414 oral study with dimethylsilanediol (DMSD). General Population exposure would be to the hydrolysis product DMSD so no conversion to corresponding dose of dichloro(dimethyl)silane required.  The following correction was made to the NOAEL (oral): Correction respiratory volume rat (24 hour) 1/1.15 m3/kg bw/day. Therefore the corrected NOAEC for repeated-dose systemic effects via the inhalation route is: 250 mg/kg/day*(1/1.15) = 217 mg/m3.

AF for dose response relationship:
1
Justification:
Default
AF for differences in duration of exposure:
1
Justification:
Default (developmental effect, no duration AF needed)
AF for interspecies differences (allometric scaling):
1
Justification:
Default (oral rat to inhaled human)
AF for other interspecies differences:
2.5
Justification:
Default
AF for intraspecies differences:
10
Justification:
Default
AF for the quality of the whole database:
1
Justification:
Default (guideline study)
AF for remaining uncertainties:
1
Justification:
Default (no remaining uncertainties)
Acute/short term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
8.7 mg/m³
Most sensitive endpoint:
developmental toxicity / teratogenicity
Route of original study:
Oral
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Overall assessment factor (AF):
25
DNEL extrapolated from long term DNEL

Local effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
4.8 mg/m³
Most sensitive endpoint:
irritation (respiratory tract)
DNEL related information
DNEL derivation method:
other: EU OEL
Overall assessment factor (AF):
1
Dose descriptor:
other: 4.8
Acute/short term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
4.8 mg/m³
Most sensitive endpoint:
irritation (respiratory tract)
DNEL related information
DNEL derivation method:
other: EU OEL
Overall assessment factor (AF):
1
DNEL extrapolated from long term DNEL

General Population - Hazard via dermal route

Systemic effects

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

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:
DNEL (Derived No Effect Level)
Value:
2.5 mg/kg bw/day
Most sensitive endpoint:
developmental toxicity / teratogenicity
Route of original study:
Oral
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Overall assessment factor (AF):
100
Modified dose descriptor starting point:
NOAEL
Value:
250 mg/kg bw/day
Explanation for the modification of the dose descriptor starting point:

The DNEL for systemic effects via the oral route is determined on the basis of the OECD 414 oral study with dimethylsilanediol (DMSD). General Population exposure would be to the hydrolysis product DMSD so no conversion to corresponding dose of dichloro(dimethyl)silane required.

AF for dose response relationship:
1
Justification:
Default
AF for differences in duration of exposure:
1
Justification:
Default (developmental effect, no duration AF needed)
AF for interspecies differences (allometric scaling):
4
Justification:
Default (oral rat to oral human)
AF for other interspecies differences:
2.5
Justification:
Default
AF for intraspecies differences:
10
Justification:
Default
AF for the quality of the whole database:
1
Justification:
Default (guideline study)
AF for remaining uncertainties:
1
Justification:
Default (no remaining uncertainties)
Acute/short term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
2.5 mg/kg bw/day
Most sensitive endpoint:
developmental toxicity / teratogenicity
Route of original study:
Oral
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Overall assessment factor (AF):
100
DNEL extrapolated from long term DNEL

General Population - Hazard for the eyes

Local effects

Hazard assessment conclusion:
medium hazard (no threshold derived)

Additional information - General Population