hydronium;iron(3+);hexahydroxide;disulfate

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

supporting study

Study period:

Study completion date: 1991-12-23

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Valid and conclusive guideline study conducted under quality control but not not formally GLP. Nonetheless the study was considered acceptable by U.S. EPA, but as a deficiency it was recognized as the report does not state which phase of the study the quality assurance unit observed. The original full study report was not available, but a robust study summary is available from a U.S. EPA Memorandum.

Justification for type of information:

The Reporting Format for the Chemical Category According to ECHA (2008) Guidance R.6.2.6.2 can be found in the Endpoint Summary of Toxicokinetics, metabolism and distribution.

Data source

Reference

Reference 1

Reference Type:

other: Authority assessment report

Title:

Unnamed

Year:

1993

Reference 2

Reference Type:

study report

Title:

Unnamed

Year:

1991

Report date:

1991

Reference 3

Reference Type:

secondary source

Title:

Unnamed

Year:

1994

Report date:

1994

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EPA OPP 81-3 (Acute inhalation toxicity)

Test guideline 2

Qualifier:

equivalent or similar to guideline

Guideline:

EPA OPPTS 870.1300 (Acute inhalation toxicity)

GLP compliance:

not specified

Remarks:

Quality assurance (40 CFR §160.12) included

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Ferric sulphate anhydrous

IUPAC Name:

Ferric sulphate anhydrous

Constituent 2

Reference substance name:

Diiron tris(sulphate)

EC Number:

233-072-9

EC Name:

Diiron tris(sulphate)

Cas Number:

10028-22-5

Molecular formula:

Fe2(SO4)3

IUPAC Name:

diiron tris(sulphate)

Test material form:

other: off-white powder /granules

Details on test material:

- Name of test material (as cited in study report): iron (III) sulfate

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Lab colony
- Age at study initiation: Young adult
- Weight at study initiation: 242-267 g males, 202-219 g females

Administration / exposure

Route of administration:

inhalation

Type of inhalation exposure:

whole body

Vehicle:

air

Details on inhalation exposure:

TEST ATMOSPHERE
- MMAD (Mass median aerodynamic diameter) 2.75±5.925 µm Geometric Standard Deviation

Analytical verification of test atmosphere concentrations:

yes

Remarks:

gravimentic

Duration of exposure:

4 h

Concentrations:

Nominal 18.5 mg/L, analytical (gravimetric) 1.1 mg/L

No. of animals per sex per dose:

5 males and 5 females

Control animals:

no

Results and discussion

Effect levels

Effect levels 1

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 1.1 mg/L air (analytical)

Based on:

test mat.

Remarks:

Fe2(SO4)3

Exp. duration:

4 h

Remarks on result:

other: MMAD 2.75±5.925 µm; Nominal dose 18.5 mg/L, analytical (gravimetric) 1.1 mg/L

Effect levels 2

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 0.3 mg/L air (analytical)

Based on:

element

Remarks:

Fe

Exp. duration:

4 h

Remarks on result:

other: Converted on the basis of molecular weights

Effect levels 3

Sex:

male/female

Dose descriptor:

discriminating conc.

Effect level:

1.1 mg/L air (analytical)

Based on:

test mat.

Remarks:

Fe2(SO4)3

Exp. duration:

4 h

Remarks on result:

other: MMAD 2.75±5.925 µm; Nominal dose 18.5 mg/L, analytical (gravimetric) 1.1 mg/L

Effect levels 4

Sex:

male/female

Dose descriptor:

discriminating conc.

Effect level:

0.3 mg/L air (analytical)

Based on:

element

Remarks:

Fe

Exp. duration:

4 h

Remarks on result:

other: Converted on the basis of molecular weights

Mortality:

All animals survived

Clinical signs:

other: Yellow perineal staining, back covered with test material

Gross pathology:

No pathologic findings

Any other information on results incl. tables

Reported mortality

Exposure concentration	Number killed / number tested
	Males	Females	Combined
1.1 mg/L	0/5	0/5	0/10

Chamber Atmosphere

Dose level	MMAD	GSD	particles < 4 µm	particles < 1.4 µm
1.1 mg/L	2.75 µm	5.925 µm	57.65 %	32.6 %

Chamber Environment

Chamber volume:	47.4 L
Airflow:	10 L/min
Temperature:	76 °F / 24.4 °C
Target relative humidity.	62-64 %

Applicant's summary and conclusion

Interpretation of results:

other: absence of effects at a limit lower than the classification cut-off

Remarks:

Criteria used for interpretation of results: EU

Conclusions:

No toxicity at 1.1 mg/L. (discriminating dose)

Executive summary:

The acute inhalation toxicity of the test item Ferric sulphate (CAS 10028-22-5), provided as off-white powder / granules to rats was investigated in 40 CFR §160.12 quality assurance study according to the EPA OPP 81-3 (Acute inhalation toxicity) standards (comparable to EPA OPPTS 870.1300), however the report does not state which phase of the study the quality assurance unit observed. Nonetheless it can be assumed that comparable standards applied as the test was conducted in a specialized laboratory. The reporting is limited but the basic information is given. The experiment is deemed valid, conclusive and suitable for assessment with minor restrictions (Klimisch 2). However reliable and relevant the experiment is not fully adequate as it does not allow concluding finally on classification. .

In a limit study design 5 male and 5 female Sprague-Dawley derived laboratory cultured rats, were during 4 h exposed to a test atmosphere of nominal 18.5 mg test item/L corresponding to analytical (gravimetric) 1.1 mg test item/L. Consequently the observations were assigned to the measure concentration. The test atmosphere was characterized by MMAD (Mass median aerodynamic diameter) 2.75±5.925 µm Geometric Standard Deviation, 57.65 % of the particles were < 4 µm, and 32.6 % particles were < 1.4 µm. No control group was involved.

No mortality was observed and no observation of sublethal effects was made, but the test organisms showed yellow perineal staining and their back was covered with test material due to the whole body exposure. Therefore a discriminating concentration of 1.1 mg test item/L was evidenced, which means that the LD50 can be assigned to be significantly greater than this level.

In summary no effects were visible in the classifiable range up to >1.0 mg/L bw (lower border of CLP up to 5th ATP, 2013, acute toxicity hazard category 4 for dusts and mists and DSD, R20 Harmful by inhalation) but no evidence for the absence of effects until 5.0 mg/L (upper border of CLP up to 5th ATP, 2013, acute toxicity hazard category 4 for dusts and mists and DSD, R20 Harmful by inhalation) is given.

Therefore classification in accordance with EU CLP Regulation (EC) No 1272/2008 of 14 May 2009, chapter 3.1 or Commission Directive 2001/59/EC of 6 August 2001, chapter 3.2.3, p. L 225/274 cannot be decided on the basis of this study alone, but more severe classification than acute toxicity hazard category 4 (CLP) or R20 Harmful by inhalation (DSD) is discouraged by the results of this study.