Registration Dossier

Administrative data

Workers - Hazard via inhalation route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
5.61 mg/m³
Most sensitive endpoint:
repeated dose toxicity
DNEL related information
Overall assessment factor (AF):
25
Modified dose descriptor starting point:
NOAEC
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

Local effects

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

Workers - Hazard via dermal route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
1.59 mg/kg bw/day
Most sensitive endpoint:
repeated dose toxicity
DNEL related information
Overall assessment factor (AF):
100
Modified dose descriptor starting point:
NOAEL
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

Local effects

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

Workers - Hazard for the eyes

Local effects

Hazard assessment conclusion:
medium hazard (no threshold derived)

Additional information - workers

Workers might be exposed to sodium silicate during manufacture, processing or filling in appropriate containers.

The dermal as well as the inhalation DNEL for workers were determined using route-to-route extrapolation (see xxx).

The existing OEL (TRGS 900, June 2008) for dust is 3 mg/m3(alveolar fraction) and 10 mg/m3(respirable fraction). The more critical value of 3 mg/m3is based on effects (5% elevation of the prevalence for chronic bronchitis and lung emphysema) observed in epidemiological studies taking into account a typical dust density at the workplace of 2.5 mg/cm3.

The derived DNEL for inhalation is higher than the existing OEL for dust, therefore long-term systemic effects caused by sodium silicate are not expected to occur as long as the OEL is complied with. However, because of the high alkalinity of sodium silicate, local effects to the skin, eyes and respiratory tract have to be accounted for.

General Population - Hazard via inhalation route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
1.38 mg/m³
Most sensitive endpoint:
repeated dose toxicity
DNEL related information
Overall assessment factor (AF):
50
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

Local effects

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

General Population - Hazard via dermal route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
0.8 mg/kg bw/day
Most sensitive endpoint:
repeated dose toxicity
DNEL related information
Overall assessment factor (AF):
200
Modified dose descriptor starting point:
NOAEL
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

Local effects

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

General Population - Hazard via oral route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
0.8 mg/kg bw/day
Most sensitive endpoint:
repeated dose toxicity
DNEL related information
Overall assessment factor (AF):
200
Modified dose descriptor starting point:
NOAEL
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

General Population - Hazard for the eyes

Local effects

Hazard assessment conclusion:
medium hazard (no threshold derived)

Additional information - General Population

The direct and indirect skin contact, inhalation and oral routes as well as the accidental overexposure (eye or oral exposure) were identified and assessed by HERA (2005) as relevant consumer exposure scenarios for sodium silicate.The primary exposure results from dermal contact. Short-term exposure to dust may occur by the use of products in powder/granular form only, other application forms are of no concern with respect to inhalative exposure. Oral exposure for consumers usually plays a minor role.