Iron sulphide

Genetic toxicity: in vivo

Administrative data

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus

Type of information:

experimental study

Adequacy of study:

key study

Justification for type of information:

See attached read-across justification

Cross-reference

Reason / purpose for cross-reference:

read-across source

Reference

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2004

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to GLP and valid methods, therefore it is considered relevant, reliable and adequate for classification. The data are from a secondary source of reliable instance and the level of detail was high.

Qualifier:

according to guideline

Guideline:

OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)

Deviations:

yes

Remarks:

one sex only (male)

GLP compliance:

yes

Type of assay:

micronucleus assay

Species:

mouse

Strain:

ICR

Sex:

male

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: 7 weeks

Route of administration:

intraperitoneal

Vehicle:

- Vehicle(s)/solvent(s) used:corn oil

Details on exposure:

intraperitoneal injection

Duration of treatment / exposure:

24h

Frequency of treatment:

once a day for two days (only positive control group was dosed once)

Post exposure period:

Sampling times: 24 hours after administration

Dose / conc.:

0 mg/kg bw/day (actual dose received)

Remarks:

intraperitoneal injection

Dose / conc.:

12.5 mg/kg bw/day (actual dose received)

Remarks:

intraperitoneal injection

Dose / conc.:

25 mg/kg bw/day (actual dose received)

Remarks:

intraperitoneal injection

Dose / conc.:

50 mg/kg bw/day (actual dose received)

Remarks:

intraperitoneal injection

No. of animals per sex per dose:

6

Control animals:

yes, concurrent vehicle

Positive control(s):

mitomycin C
- Route of administration: intraperitoneal injection
- Doses / concentrations: 2.0 mg/kg bw

Tissues and cell types examined:

Bone marrow cells

Details of tissue and slide preparation:

CRITERIA FOR DOSE SELECTION:
- Criteria for selection of maximum tolerated dose (MTD): preliminary tests were conducted to determine the maximum tolerated dose. Two males of ICR mice were dosed at 2000 mg/kg bw/day and three males each were dosed at 20, 50, 100, 200, 500 and 1000 mg/kg bw/day dose levels once a day for two consecutive days. All animals of 200, 500, 1000 and 2000 mg/kg bw/day dose levels and one animal of 100 mg/kg bw/day were dead after the first dosing. Two animals of 100 mg/kg/day group and all of 50 and 20 mg/kg/day groups showed piloerection after the first dosing. After the second dosing, piloerection and hypoactivity were observed in all animals of 100 mg/kg bw/day and piloerection was observed in all animals of 50 and 20 mg/kg bw/day groups. One animal of 100 mg/kg bw/day group was dead 2days after the second dosing.

TREATMENT AND SAMPLING TIMES ( in addition to information in specific fields): intraperitoneal injection; sampling time 24 h after administration

OTHER:
- Clinical observations performed: Yes
- Organs examined at necropsy: Not examined

Evaluation criteria:

At least 2000 polychromatic erythrocytes per animals were scored for the incidence of micronuclei.

Statistics:

Chi-square test(using a 2×2 contingency table)

Key result

Sex:

male

Genotoxicity:

negative

Toxicity:

yes

Vehicle controls validity:

valid

Positive controls validity:

valid

Main tests:

After first dosing, one animal of 50 mg/kg bw/day dose level was dead and piloerection was observed in all animals of 25 and 50 mg/kg bw/day groups. After second dosing, piloerection and hypoactivity were observed in three animals of 50 mg/kg bw/day group. Any clinical sign was not observed in 12.5 mg/kg bw/day group.

Table1. Summary of PCE/(PCE+NCE) ratio and MNPCE frequency

Treatment group	PCE/(PCE+NCE) (mean)	Group mean frequency of MNPCE per 2000 PCE (mean±S.D.)
Vehicle (10 mL/kg) Iron dichloride (12.5 mg/kg) Iron dichloride (25 mg/kg) Iron dichloride (50 mg/kg) Mitomycin C (2 mg/kg)	0.58 0.61 0.56 0.51 0.54	3.8 ± 2.3 3.8 ± 1.6 3.7 ± 1.5 2.0 ± 1.0 185.7 ± 16.3SS

SS: Statistical significance was observed (p ≤ 0.05)

Conclusions:

Interpretation of results: negative
Iron dichloride did not induce micronuclei in the mice bone marrow cells under the test conditions.

Executive summary:

6 Male ICR mice per dose level were administered iron dichloride by intraperitoneal injection at dose levels of 0, 12.5, 25 and 50 mg/kg bw once daily for two days. The negative controls were administered 10 mL/kg corn oil (vehicle) in the same way. The positive control animals received Mitomycin C 2 mg/kg only once. After first dosing, one animal of 50 mg/kg bw/day dose level was dead and piloerection was observed in all animals of 25 and 50 mg/kg bw/day groups. After second dosing, piloerection and hypoactivity were observed in three animals of 50 mg/kg bw/day group. Any clinical sign was not observed in 12.5 mg/kg bw/day group. Iron dichloride did not induce micronuclei in the mice bone marrow cells under the test conditions.

Materials and methods

Test material

Test material information

Constituent 1

Reference substance name:

Iron sulphide

EC Number:

215-268-6

EC Name:

Iron sulphide

Cas Number:

1317-37-9

Molecular formula:

FeS

IUPAC Name:

sulfanylideneiron

Results and discussion

Test results

Key result

Sex:

male

Genotoxicity:

negative

Toxicity:

yes

Vehicle controls validity:

valid

Positive controls validity:

valid

Any other information on results incl. tables

Main tests:

After first dosing, one animal of 50 mg/kg bw/day dose level was dead and piloerection was observed in all animals of 25 and 50 mg/kg bw/day groups. After second dosing, piloerection and hypoactivity were observed in three animals of 50 mg/kg bw/day group. Any clinical sign was not observed in 12.5 mg/kg bw/day group.

Table1. Summary of PCE/(PCE+NCE) ratio and MNPCE frequency

Treatment group	PCE/(PCE+NCE) (mean)	Group mean frequency of MNPCE per 2000 PCE (mean±S.D.)
Vehicle (10 mL/kg) Iron dichloride (12.5 mg/kg) Iron dichloride (25 mg/kg) Iron dichloride (50 mg/kg) Mitomycin C (2 mg/kg)	0.58 0.61 0.56 0.51 0.54	3.8 ± 2.3 3.8 ± 1.6 3.7 ± 1.5 2.0 ± 1.0 185.7 ± 16.3SS

SS: Statistical significance was observed (p ≤ 0.05)

Applicant's summary and conclusion

Conclusions:

Interpretation of results: negative
Read-across substance iron dichloride did not induce micronuclei in the mice bone marrow cells under the test conditions.

Executive summary:

6 Male ICR mice per dose level were administered read-across substance iron dichloride by intraperitoneal injection at dose levels of 0, 12.5, 25 and 50 mg/kg bw once daily for two days. The negative controls were administered 10 mL/kg corn oil (vehicle) in the same way. The positive control animals received Mitomycin C 2 mg/kg only once. After first dosing, one animal of 50 mg/kg bw/day dose level was dead and piloerection was observed in all animals of 25 and 50 mg/kg bw/day groups. After second dosing, piloerection and hypoactivity were observed in three animals of 50 mg/kg bw/day group. Any clinical sign was not observed in 12.5 mg/kg bw/day group. Read-across substance iron dichloride did not induce micronuclei in the mice bone marrow cells under the test conditions.