Mill scale (ferrous metal)

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

abstract

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1977

Report date:

1977

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

10 male Wistar rats were dosed with 10000 mg/kg bw of Eisenoxidgelb 920 (FeO(OH) in water by a single oral application by gavage. During post observation time of 14 days, the animals were exanimated for clinical signs and mortality.

GLP compliance:

not specified

Remarks:

Study was conducted prior to implementation of GLP in the EU.

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Iron hydroxide oxide yellow

EC Number:

257-098-5

EC Name:

Iron hydroxide oxide yellow

Cas Number:

51274-00-1

Molecular formula:

Fe(OH)O

IUPAC Name:

Iron hydroxide oxide

Test material form:

solid: nanoform

Details on test material:

FeOOH (Eisenoxidgelb 920)

Test animals

Species:

rat

Strain:

Wistar

Sex:

male

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Winkelmann, Borchen
- Age at study initiation: not specified
- Weight at study initiation: 160 - 180 g males
- Housing:5 animals per cage

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

not specified

Doses:

10000 mg/kg bw

No. of animals per sex per dose:

10

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: not specified

Statistics:

No statistical analysis could be performed ( the method used is not intended to allow a calculation of a precise LD50 value).

Results and discussion

Effect levels

Key result

Sex:

male

Dose descriptor:

LD50

Effect level:

> 10 000 mg/kg bw

Based on:

test mat.

Mortality:

no mortality was observed

Clinical signs:

other: no clinical signs (not specified) were observed

Body weight:

other body weight observations

Remarks:

not specified

Gross pathology:

not specified

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The LD50 cannot be determined, based to the absence of mortality and other effects. Based on the maximal limit dose tested of it could be considered that the LD50 of FeO(OH) is >10000 mg/kg bw/d. According to the Regulation (EC) No 1272/2008 and subsequent adaptions, the substance is not acutely toxic via the oral route.

The study was executed before the establishment of OECD guidelines and the short study report was provided in an abstract like form. Consequently, the study was ranked as “not assignable” (RL4).

Executive summary:

In an acute oral toxicity study, male Wistar rats were given a single oral dose of FeOOH in water, at a dose of  10,000  mg/kg bw (limit test); the treatment was followed by 14 days of observation. No mortality and no signs of toxicity were observed. The study yielded an oral LD50 of > 10000 mg/kg bw in male rats for FeOOH. Based on the results of this study, classification and labelling for acute oral toxicity is not required.