Registration Dossier

Administrative data

Workers - Hazard via inhalation route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
2.23 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):
75
Modified dose descriptor starting point:
NOAEC
DNEL value:
167 mg/m³
Explanation for the modification of the dose descriptor starting point:
assuming 10% absorption via oral and 10% via inhalative route the NOAEL of 95 mg/kg bw/d from a subacute study with the analogue BaDNNSA is corrected by multiplying with 10/10 and division by 0.38 m3/kg for air consumption and multiplication with 6.7/10 for light work adjustment --> NOAECcorr = 55 mg/kg bw/d * 10/10 * 6.7/10 / 0.38 m3/kg/d = 96 mg/m3
AF for dose response relationship:
1
Justification:
NOAEC is used as the starting point
AF for differences in duration of exposure:
6
Justification:
based on the subacute study
AF for interspecies differences (allometric scaling):
1
Justification:
allometric scaling is not applied for the derivation of inhalation DNEL.
AF for other interspecies differences:
2.5
Justification:
no other substance-specific data are available.
AF for intraspecies differences:
5
Justification:
default factor for workers
AF for the quality of the whole database:
1
Justification:
Available data from analogue fulfilling scientific principle is used .
AF for remaining uncertainties:
1
Justification:
no other uncertainties needed to be considered.
Acute/short term exposure
Hazard assessment conclusion:
low hazard (no threshold derived)
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
low hazard (no threshold derived)
Acute/short term exposure
Hazard assessment conclusion:
low 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:
0.316 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
Modified dose descriptor starting point:
NOAEL
DNEL value:
95 mg/kg bw/day
Explanation for the modification of the dose descriptor starting point:
In general, dermal absorption will not be higher than oral absorption, no default factor (i.e. factor 1) should be introduced when performing oral-to-dermal extrapolation and absorption rates are assumed 10% for both routes.
AF for dose response relationship:
1
Justification:
NOAEL is used as the starting point
AF for differences in duration of exposure:
6
Justification:
based on the subacute study
AF for interspecies differences (allometric scaling):
4
Justification:
rats are used
AF for other interspecies differences:
2.5
Justification:
no other substance-specific effects are available
AF for intraspecies differences:
5
Justification:
default factor for workers
AF for the quality of the whole database:
1
Justification:
Available data fulfill the scientific requirements
AF for remaining uncertainties:
1
Justification:
no other uncertainties need to be considered.
Acute/short term exposure
Hazard assessment conclusion:
no DNEL required: short term exposure controlled by conditions for long-term
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

Zinc bis( di C8-C10, branched, C9 rich, alkylnaphthalene sulphonate) has a low vapour pressure and is not expected to volatilize. Inhalation exposure to the vapour or aerosols (see uses) is unlikely to be a relevant route of exposure to human in regular use.

A worst case scenario is assumed in which the absorption rate for the dermal route is considered to be same as oral route, and for both routes assumed to be 10% (see toxicokinetic assessment).

OECD 422 studies were conducted with 2 analogues: DNNSA (di C8-C10, branched, C9 rich, alkylnaphthalene sulphonic acid) and BaDNNSA (Barium bis( di C8-C10, branched, C9 rich, alkylnaphthalene sulphonate). The NOAEL for DNNSA is 95 mg/kg/day and the NOAEL for BaDNNSA is 55 mg/kg/day.

DNNSA provides the best read-across for ZnDNNSA because DNNSA is the major component of ZnDNNSA and the presence of the zinc moiety would not contribute significantly to the toxicity. The NOAEL for Barium DNNSA is lower than the NOAEL for DNNSA principally related to the presence of the barium moiety. The NOAEL for Barium DNNSA is based on effects on the kidney which is known as the target organ for barium toxicity.

Based on these results, the No Observed Adverse Effect Levels (NOAEL) used as starting point for the derivation of the DNELs was established as 95 mg/kg, the NOAEL for DNNSA.

According to ECHA guidance document the oral NOAEL is converted to an inhalation NOAECWorkerof 167 mg/m3(0.38 m3/kg in case of 8 h exposure/d for worker and 6.7/10 for light work adjustment), and as inhalative and dermal absorption both are assumed being 10% no correction was applied.

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
DNEL related information
DNEL value:
5
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

No consumer exposure is anticipated