Registration Dossier

Administrative data

Workers - Hazard via inhalation route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
1.25 mg/m³
DNEL related information
DNEL derivation method:
other: The general exposure limit for inhalable dust is applied
Explanation for the modification of the dose descriptor starting point:

Because no inhalation study is available, a route to route extrapolation was performed. The NOAEL (oral) is converted into a NOAEC (corrected) in accordance to guidance on information requirements and chemical safety assessment, Chapter R.8, ECHA, 2012. The NOAEL (oral) has to be divided by a factor of 0.38 m3/kg body weight and corrected for activity driven differences of respiratory volumes in workers compared to workers in rest (6.7 m3/10 m3). In addition, a default factor of 2 is applied to account for differences in oral and inhalative absorption properties. The corrected starting point is therefore:

NOAEC (corrected) = 1000 mg/kg / 0.38 m3/kg x 0.5 x (6.7 m3/10m3) = 882 mg/m3

The DNEL is calculated as follows: NOAEC (corrected) / Sum of assessment factors applicable.

The following assessment factors according to "ECHA guidance on information requirements and chemical safety assessment, Chapter R8" were chosen:

Intraspecies differences (worker): 5

Interspecies variations: 2.5

Exposure duration: 6

Dose-response factor: 1

Quality of whole database factor: 1

The overall assessment factor employed for the inhalation route is therefore 75.

DNEL = 882 mg/m3/ 75 = 11.75 mg/m3

However, since the substance is an insoluble solid for which no systemic hazard was identified by the oral route, the systemic DNEL derived above is considered not relevant. The main hazard results if dusty material is inhaled at doses at which the natural clearance function of the lung is overloaded. To protect against this effect, the general exposure limit of 1.25 mg/m3 for inhalable inert dust is applied.

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

Local effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
1.25 mg/m³
DNEL related information
DNEL derivation method:
other: The general exposure limit for inhalable dust is applied
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

Workers - Hazard via dermal route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
33.3 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):
300
Dose descriptor starting point:
NOAEL
Value:
1 000 mg/kg bw/day
Modified dose descriptor starting point:
NOAEL
Value:
10 000 mg/kg bw/day
Explanation for the modification of the dose descriptor starting point:

The dermal route is typically covered by oral route information in the absence of data for this administration route. The test substance is characterized by low solubility in both water and organic solvents. In addition, the molecular weight is above 500. As a result, absorption via the dermal route is anticipated to be <10% and the NOAEL is adjusted accordingly.

AF for dose response relationship:
1
Justification:
The dose response relationship is considered unremarkable, therefore no additional factor is used.
AF for differences in duration of exposure:
6
Justification:
The default extrapolation factor for exposure duration is used: subacute (starting point) to chronic (end point).
AF for interspecies differences (allometric scaling):
4
Justification:
The default allometric scaling factor for the differences between rats and humans is used.
AF for other interspecies differences:
2.5
Justification:
Recommended AF for other interspecies differences.
AF for intraspecies differences:
5
Justification:
The default value for the relatively homogenous group "worker" is used.
AF for the quality of the whole database:
1
Justification:
The quality of the whole data base is considered to be sufficient and uncritical.
AF for remaining uncertainties:
1
Justification:
The approach used for DNEL derivation is conservative. No further assessment factors are required.
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

Workers - Hazard for the eyes

Local effects

Hazard assessment conclusion:
no hazard identified

Additional information - workers

Identification of relevant dose descriptor

The test substance is a solid with very low solubility properties and no signs of toxicity in any of the studies performed, indicating that the test article's potential to be systemically available is very low. Nevertheless, DNELs for systemic effects are established for a worst case assessment. In the available combined repeated dose toxicity study with the reproduction / developmental toxicity screening performed with the test item, a NOAEL of 1000 mg/kg body weight was established (highest doses tested). This value was used as point of departure for DNEL calculation.

General Population - Hazard via inhalation 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
DNEL related information

General Population - Hazard via dermal route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
16.7 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):
600
Dose descriptor starting point:
NOAEL
Value:
1 000 mg/kg bw/day
Modified dose descriptor starting point:
NOAEL
Value:
10 000 mg/kg bw/day
Explanation for the modification of the dose descriptor starting point:

The dermal route is typically covered by oral route information in the absence of data for this administration route. The test substance is characerized by low solubility in both water and organic solvents. In addition, the molecular weight is above 500. As a result, absorption via the dermal route is anticipated to be <10% and the NOAEL is adjusted accordingly.

AF for dose response relationship:
1
Justification:
The dose response relationship is considered unremarkable, therefore no additional factor is used.
AF for differences in duration of exposure:
6
Justification:
The default extrapolation factor for exposure duration is used: subacute (starting point) to chronic (end point).
AF for interspecies differences (allometric scaling):
4
Justification:
The default allometric scaling factor for the differences between rats and humans is used.
AF for other interspecies differences:
2.5
Justification:
Recommended AF for other interspecies differences.
AF for intraspecies differences:
10
Justification:
The default value for the more heterogenous group "general population" is used.
AF for the quality of the whole database:
1
Justification:
The quality of the whole data base is considered to be sufficient and uncritical.
AF for remaining uncertainties:
1
Justification:
The approach used for DNEL derivation is conservative. No further assessment factors are required.
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:
1.67 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):
600
Dose descriptor starting point:
NOAEL
Value:
1 000 mg/kg bw/day
AF for dose response relationship:
1
Justification:
The dose response relationship is considered unremarkable, therefore no additional factor is used.
AF for differences in duration of exposure:
6
Justification:
The default extrapolation factor for exposure duration is used: subacute (starting point) to chronic (end point).
AF for interspecies differences (allometric scaling):
4
Justification:
The default allometric scaling factor for the differences between rats and humans is used.
AF for other interspecies differences:
2.5
Justification:
Recommended AF for other interspecies differences.
AF for intraspecies differences:
10
Justification:
The default value for the more heterogenous group "general population" is used.
AF for the quality of the whole database:
1
Justification:
The quality of the whole data base is considered to be sufficient and uncritical.
AF for remaining uncertainties:
1
Justification:
The approach used for DNEL derivation is conservative. No further assessment factors are required.
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

General Population - Hazard for the eyes

Local effects

Hazard assessment conclusion:
no hazard identified

Additional information - General Population

Identification of relevant dose descriptor

The dose descriptor chosen is the same as for workers (see above). The NOAEL of 1000 mg/kg was used as starting point to derive the DNELs.