Registration Dossier

Administrative data

Workers - Hazard via inhalation route

Systemic effects

Long term exposure
Hazard assessment conclusion:
high hazard (no threshold derived)
Acute/short term exposure
Hazard assessment conclusion:
high hazard (no threshold derived)
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
16.51 mg/m³
Most sensitive endpoint:
skin irritation/corrosion
DNEL related information
DNEL derivation method:
other: based on EU OEL of HCl
Overall assessment factor (AF):
1
Acute/short term exposure
Hazard assessment conclusion:
high hazard (no threshold derived)
Most sensitive endpoint:
skin irritation/corrosion
DNEL related information

Workers - Hazard via dermal route

Systemic effects

Long term exposure
Hazard assessment conclusion:
high hazard (no threshold derived)
Acute/short term exposure
Hazard assessment conclusion:
high hazard (no threshold derived)
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
high hazard (no threshold derived)
Acute/short term exposure
Hazard assessment conclusion:
high hazard (no threshold derived)

Workers - Hazard for the eyes

Local effects

Hazard assessment conclusion:
high hazard (no threshold derived)

Additional information - workers

There are no adequate data regarding the repeated dose toxicity of trichloro(4 -methylphenyl)silane or its hydrolysis product 4 -methylphenylsilanetriol, therefore data from the other hydrolysis product HCl is considered appropriate to determine local DNELs for the parent substance. Trichloro(4 -methylphenyl)silane hydrolyses very rapidly (half-live of < 1 min at pH 7) in contact with moist air and in contact with tissues to form 3 moles of hydrogen chloride (HCl) and one mole of 4 -methylphenylsilanetriol. Local effects (corrosion) are therefore influenced by the formation of HCl.

Long-term exposure –Local effects:

 

Inhalation DNEL:

Since each mole of trichloro(4 -methylphenyl)silane (molecular weight 225.575 g/mol) produces three moles of HCl (molecular weight 36.46 g/mol), it is appropriate to calculate the starting concentration of trichloro(4 -methylphenyl)silane that would result in an exposure concentration of 8 mg/m3 HCl, assuming complete hydrolysis.

The equivalent exposure level expressed as parent trichloro(4 -methylphenyl)silane is calculated as:

MW (HCl) = 36.46 g/mol

MW trichloro(4 -methylphenyl)silane = 225.575 g/mol

Amount HCl produced by 1 mole trichloro(4 -methylphenyl)silane = 3 x 36.46 g/mol = 109.38 g. Concentration of trichloro(4 -methylphenyl)silane required to produce 8 mg/m3 HCl = (225.757/109.38)*8 = 16.51 mg/m³.

No additional assessment factors are applied to the OEL.

Dermal DNEL:

The RMMs in place due to the corrosivity of the substance will prevent dermal exposure.

Inhalation DNEL (Long-term exposure - local effects, worker): 16.51 mg/m3

Long term exposure – Systemic effects

Because of the corrosivity of the substance, the DNEL for local effects is considered sufficiently protective against potential systemic effects.

Hydrogen chloride (HCl)

An EU long-term inhalation Occupational Exposure Limit (OEL) has been set for HCl as 8 mg/m3 (8 h TWA) in Commission Directive2000/39/EC.

The SIDS Initial Assessment Report (SIAR) for HCl describes a systemic NOAEL of 20 ppm from a 90-day repeated dose inhalation study (OECD, 2002). However, since the NOAEL for local effects in the same study was 10 ppm it is considered by the author of this CSR that the observed effects at 20 ppm were secondary to corrosion.

It is therefore considered appropriate to use the existing EU OEL for HCl as the starting point to quantify local DNELs for trichloro(4 -methylphenyl)silane.

General Population - Hazard via inhalation route

Systemic effects

Long term exposure
Hazard assessment conclusion:
hazard unknown but no further hazard information necessary as no exposure expected
Acute/short term exposure
Hazard assessment conclusion:
hazard unknown but no further hazard information necessary as no exposure expected
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
hazard unknown but no further hazard information necessary as no exposure expected
Acute/short term exposure
Hazard assessment conclusion:
hazard unknown but no further hazard information necessary as no exposure expected
DNEL related information

General Population - Hazard via dermal route

Systemic effects

Long term exposure
Hazard assessment conclusion:
hazard unknown but no further hazard information necessary as no exposure expected
Acute/short term exposure
Hazard assessment conclusion:
hazard unknown but no further hazard information necessary as no exposure expected
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
hazard unknown but no further hazard information necessary as no exposure expected
Acute/short term exposure
Hazard assessment conclusion:
hazard unknown but no further hazard information necessary as no exposure expected

General Population - Hazard via oral route

Systemic effects

Long term exposure
Hazard assessment conclusion:
hazard unknown but no further hazard information necessary as no exposure expected
Acute/short term exposure
Hazard assessment conclusion:
hazard unknown but no further hazard information necessary as no exposure expected
DNEL related information

General Population - Hazard for the eyes

Local effects

Hazard assessment conclusion:
hazard unknown but no further hazard information necessary as no exposure expected

Additional information - General Population

There is no potential for exposure of consumers via any route to trichloro(4 -methylphenyl)silane, therefore DNELs for consumers are not calculated.