Iron hydroxide oxide yellow

Endpoint summary

Description of key information

In an oral acute toxicity study 10 animals were treated with 10000 mg/kg bw FeOOH. During an observation  time of 14 days none of the animals showed signs of toxicity or died. In an  acute inhalation toxicity study with Fe2O3 as a surrogate for the iron oxide group the discriminating dose was 5050 mg/m³. No study for acute dermal toxicity is available.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: scientifically acceptable and sufficient documented

Principles of method if other than guideline:

Single oral application by means of gavage

GLP compliance:

not specified

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

male

Route of administration:

oral: gavage

Vehicle:

water

Doses:

10 g/kg

No. of animals per sex per dose:

10

Control animals:

not specified

Sex:

male

Dose descriptor:

LD50

Effect level:

> 10 000 mg/kg bw

Clinical signs:

other:

Executive summary:

10 animals were treated with 10000 mg/kg bw of the test substance. During an observation time of 14 days none of the animals showed signs of toxicity or died.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

discriminating dose

Value:

10 000 mg/kg bw

Quality of whole database:

scientifically acceptable and sufficient documented

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: as reported in source record

Justification for type of information:

see attachment "Endpoint-specific read-across justification for the iron oxide category" in section 13.

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Duration of exposure:

4 h

Sex:

male/female

Dose descriptor:

discriminating conc.

Effect level:

5.05 mg/L air

Based on:

test mat.

Exp. duration:

4 h

Executive summary:

Five male and 5 female Wistar rats were exposed single to 5 mg/l CERAC-Pigment (average particle size = 35 nm) for 4 hours. The animals were observed for mortality, clinical signs and body weight during a post-observation period of 14 days. A pathological examination was performed on all animals which died during the observation period or were sacrificed at the end of the study period.

Following a single snout only inhalation exposures to CERAC-Pigment for four hours at an aerosol concentration of 5 mg/L, all animals tolerated the exposure. The Median Lethal Concentration (MLC) was therefore considered to be in excess of 5 mg/L.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

discriminating conc.

Value:

5 050 mg/m³ air

Quality of whole database:

GLP gudieline study

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Data waiving:

other justification

Justification for data waiving:

the study does not need to be conducted because inhalation of the substance is likely

the study does not need to be conducted because the substance does not meet the criteria for classification as acute toxicity or STOT SE by the oral route and no systemic effects have been observed in in vivo studies with dermal exposure (e.g. skin irritation, skin sensitisation)

Clinical signs:

other:

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

In a reliable acute toxicity study rats received per gavage doses of 10000 mg/kg bw of the test substance. Neither symptoms nor mortality were observed. Therefore the discriminating dose is > 10000 mg/kg bw.

No study for acute dermal toxicity is available. In a 2 week inhalation toxicity study (6 hours/day on 5 days/week) in rats 195 mg/m³ FeOOH (nanomaterial) caused no death in the test animals. Therefore based on this study the discriminating dose for FeOOH is > 195 mg/m³/6 h. In an additional acute inhalation toxicity study with Fe2O3 as a surrogate for the iron oxide group the discriminating dose was 5050 mg/m³. No study for acute dermal toxicity is available. Due to its structure and physicochemical properties (insoluble in water and organic solvents) no systemic bioavailability is expected by the dermal route.

Justification for selection of acute toxicity – oral endpoint

Key study is used

Justification for selection of acute toxicity – inhalation endpoint

key study is used

Justification for classification or non-classification

In an oral acute toxicity study 10 animals were treated with 10000 mg/kg bw FeOOH. During an observation time of 14 days none of the animals showed signs of toxicity or died. In an acute inhalation toxicity study with Fe2O3 as a surrogate for the iron oxide group the discriminating dose was 5050 mg/m³. No study for acute dermal toxicity is available. Due to its structure and physicochemical properties (insoluble in water and organic solvents) no systemic bioavailability is expected.

A classification is not required.