Dipotassium hexacyanocobalt(II)-ferrate(II)

Toxicological Summary

Workers - Hazard via inhalation route

Systemic effects

Long term exposure

Hazard assessment conclusion:

DNEL (Derived No Effect Level)

Value:

3.5 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

Dose descriptor starting point:

NOAEL

Value:

30 mg/kg bw/day

Modified dose descriptor starting point:

NOAEC

Value:

264.5 mg/m³

Explanation for the modification of the dose descriptor starting point:

Extrapolation from an oral subacute study to workers' inhalation route. The inhalatory absorption rate for the substance has been estimated to be 10 %, based on the fact that the substance is highly insoluble in water with a molecular weight of 349, has a very low vapour pressure (< 1.2 x 10^-9 Pa) and a large particle size (1.05% of particles <100 µm).

NOAECcorr=NOAELoral*(1/0.38 m³/kg/d)*(ABSoral-rat/ABSinh-human)*(6.7 m³ (8h)/10 m³ (8h)) = 30 mg/kg/d*(1/0.38 m³/kg/d)*(0.5/0.1)*0.67=264,5 mg/m³.

It is assumed that oral absorption rate is 50% of that of inhalation absorption. ABSoral-rat=oral absorption rate in rats, ABSinh-human=inhalation absorption rate in humans.

AF for dose response relationship:

1

Justification:

Oral NOAEL to inhalatory NOAEC

AF for differences in duration of exposure:

6

Justification:

DNEL is based on an oral subacute study: assessment factor for subacute to chronic applied

AF for interspecies differences (allometric scaling):

1

Justification:

Allometric scaling not used for inhalation

AF for other interspecies differences:

2.5

Justification:

Default assessment factor for other interspecies differences

AF for intraspecies differences:

5

Justification:

Default assessment factor for workers' intraspecies differences

AF for the quality of the whole database:

1

Justification:

The study has a Klimisch score = 1

AF for remaining uncertainties:

1

Justification:

No remaining uncertainties

Acute/short term exposure

Hazard assessment conclusion:

no hazard identified

DNEL related information

DNEL derivation method:

ECHA REACH Guidance

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

Workers - Hazard via dermal route

Systemic effects

Long term exposure

Hazard assessment conclusion:

DNEL (Derived No Effect Level)

Value:

1 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:

30 mg/kg bw/day

Modified dose descriptor starting point:

other: NOAEC

Value:

300 mg/kg bw/day

Explanation for the modification of the dose descriptor starting point:

Extrapolation of an oral repeated dose NOAEL from a subacute study on rats to a worker's dermal NOAEC.

The dermal absorption rate for the substance has been estimated to be 10 %, based on the fact that the substance is highly insoluble in water and has a large particle size (1.05% of particles <100 µm), with a molecular weight of 349. The dermal LD50 for the substance is >2000 mg/kg and there were no acute systemic effects after dermal exposure. Results for skin corrosion, irritation and sensitization were negative.

Dermal NOAEC=oral NOAEL*(ABSoral-rat/ABSdermal-human)=30 mg/kg bw/day*10

It is normally assumed that oral and dermal absorption rates are equal. However, in this case the dermal absorption rate for the substance has been estimated to be 10 %.

AF for dose response relationship:

1

Justification:

Oral NOAEL to dermal NOAEL

AF for differences in duration of exposure:

6

Justification:

Subacute to chronic

AF for interspecies differences (allometric scaling):

4

Justification:

Allometric scaling to compensate differences in metabolic rate/body weight in rats and humans

AF for other interspecies differences:

2.5

Justification:

Default assessment factor for other interspecies differences in accordance with ECHA Guidance

AF for intraspecies differences:

5

Justification:

Default assessment factor for workers' intraspecies differences

AF for the quality of the whole database:

1

Justification:

The study has a Klimisch score = 1

AF for remaining uncertainties:

1

Justification:

No remaining uncertainties

Acute/short term exposure

Hazard assessment conclusion:

no hazard identified

DNEL related information

DNEL derivation method:

ECHA REACH Guidance

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:

no hazard identified

DNEL related information

DNEL derivation method:

ECHA REACH Guidance

Workers - Hazard for the eyes

Local effects

Hazard assessment conclusion:

no hazard identified

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:

no hazard identified

Additional information - General Population

The substance is only marketed for industrial use and is therefore not handled by the general population. Downstream use takes place at nuclear facilities or equivalent sites that are closed, highly controlled environments. Waste from the production site is minimised and recovered for production or treated as hazardous waste. Any waste produced during downstream use is treated as radioactive or as hazardous waste. Due to the adopted risk management measures at the production site, such as ventilation exhaust air filters, and those recommended to the downstream users, the emissions of the substance to the environment are negligible, eliminating the exposure to the substance through the environment. Therefore, exposure to the substance by the general population is unlikely irrespective of exposure route.