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
Most sensitive endpoint:
repeated dose toxicity
Route of original study:
Oral
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Overall assessment factor (AF):
2
Explanation for the modification of the dose descriptor starting point:

Starting point NOAEL 50 mg Zn 2+ /person/day from Human study

Assessment factor for route to route extrapolation oral to dermal: 2 (40% absorption inhalation/ 20% absorption oral)

NOAEL: 50 x 0.5= 25 mg Zn 2+ /person/day

Conversion to inhalative volume Worker 10 m3/ person (8 h, light activities) 25 / 10 = 2.5 mg Zn 2+/m3

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:
3.57 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):
2
Explanation for the modification of the dose descriptor starting point:

Starting point NOAEL 50 mg Zn 2+/person/day from Human study

Assessment factor for route to route extrapolation oral to dermal: 0.1 (2% absorption dermal/ 20% absorption oral)

NOAEL: 50 x 10 = 500 mg Zn 2+ /person/day

Conversion to mg/kg bw/d: 70 kg 500/70 = 7.14 mg Zn 2+/kg bw/d

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)

Workers - Hazard for the eyes

Local effects

Hazard assessment conclusion:
medium hazard (no threshold derived)

Additional information - workers

The exposure of trizinc dicitrate is not expected to differ significantly from the exposure to citric acid and zinc ions separately in an aqueous matrix (oral and inhalation) and once absorbed. While the dermal absorption of trizinc dicitrate is expected to be neglegible due to the physico-chemical properties of the substance, namely the low LogKow (<1). Therefore the toxicity of trizinc dicitrate should be based on citric acid and zinc separately.

Furthermore, citric acid is a central constituent in cell metabolism and used as food additive with an ADI “not quantified”. Therefore, it is not thought appropriate or necessary to derive DNELs for this substance. Additional information can be found in the Chemical Safety Report for the Citrates Category (2010). Human data from Zinc supplement use are used as starting point for DNEL derivation, in line with assessment performed by EFSA and other risk assessment bodies like German MAK committee.

 

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:
medium hazard (no threshold derived)

Additional information - General Population