Ferric ammonium citrate

Genetic toxicity: in vivo

Administrative data

Endpoint:

in vivo mammalian germ cell study: cytogenicity / chromosome aberration

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

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

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Research paper study well documented meeting generally accepted scientific principles but not a standard micronucleus test. The original study and the read-across are considered to be reliability 2.

Data source

Reference

Reference Type:

publication

Title:

Nuclear aberrations and micronuclei induction in the digestive tract of mice treated with different iron salts.

Author:

Bianchini F, Caderni G, Dolara P, Tanagnelli E

Year:

1988

Bibliographic source:

J App Tox 8(3): 179-183

Materials and methods

Principles of method if other than guideline:

Method: other: Bruce et al (modified); Wargovich et al, J Natl Cancer Inst 71 125-131 1983

GLP compliance:

not specified

Type of assay:

other: micronucleus assay using tissues from gastrointestinal tract

Test material

Test material information

Constituent 1

Reference substance name:

Ferric chloride hexahydrate

IUPAC Name:

Ferric chloride hexahydrate

Constituent 2

Reference substance name:

10025-77-1

Cas Number:

10025-77-1

IUPAC Name:

10025-77-1

Details on test material:

Obtained from Merck and reportedly containing ca 20% Fe.
The material tested was the hexahydrate of Ferric chloride CAS number 10025-77-1 FeCl3.6H2O

Test animals

Species:

mouse

Strain:

C57BL

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River, Calco, Como, Italy
- Age at study initiation: no data
- Weight at study initiation: 17-18 g
- Fasting period before study: 12 hours (oral administration) or not fasted (rectal administration)
- Housing: no data
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: no data

Administration / exposure

Route of administration:

other: oral or intrarectal

Vehicle:

- Vehicle(s)/solvent(s) used: physiol. saline;
- Concentration of test material in vehicle: 2, 6.5 and 13 mg Fe/kg
- Amount of vehicle (if gavage or dermal): 0.2ml

Duration of treatment / exposure:

24 hours

Frequency of treatment:

Single treatment

Doses / concentrations

Remarks:

Doses / Concentrations:
2, 6.5 and 13 mg Fe/kg
Basis:

No. of animals per sex per dose:

4-9

Control animals:

yes

Positive control(s):

2-amino-3-methylimidazo(4,5,f) quinoline (IQ)
- Justification for choice of positive control(s): this is a genotoxic chemical with specific intestinal action.
- Route of administration: orally to non-fasting mice
- Doses / concentrations: 100 and 200 mg/kg bw

Examinations

Tissues and cell types examined:

Colon, duodenum and stomach mucosal cells for oral administration, colon samples after interrectal administration.

Details of tissue and slide preparation:

CRITERIA FOR DOSE SELECTION: The lowest dose tested was equivalent to a therapeutic dose in iron deficiency anaemia.

DETAILS OF SLIDE PREPARATION: colon and duodenum where opened longitudinally and rolled. The forestomach was excised. Specimens were fixed in 10% buffered formalin and processed for histology. Slides with 5 micron thick paraffin sections were stained with Feulgen-fast green.


METHOD OF ANALYSIS:
Slides were examined and scored for a) micronuclei defined as nuclear fragments not larger than ¼ -1/3 of the diameter of the primary nucleus b) nuclear aberrations comprised of micronuclei, pyknotic nuclei, cytolysosomes and disintegrated nuclei. The forestomach was analysed by observing ca 400 mucosal cells per animal. Mucosal cells lining 20 crypts for colon and 5 crypts for duodenum were analysed per animal beginning from the anal end of the colon and the pyloric end of the duodenum.


OTHER:

Results and discussion

Test results

Sex:

female

Genotoxicity:

negative

Toxicity:

yes

Remarks:

dose related toxic effects were seen in colons of feeding animals and colon and stomach of fasting animals

Vehicle controls validity:

valid

Negative controls validity:

not applicable

Positive controls validity:

valid

Any other information on results incl. tables

The reference compound IQ caused an increase of nuclear aberrations and micronuclei, results being presented for effects in the colon. 

Neither ferric chloride nor ferrous sulphate significantly increased the incidence of micronuclei in the stomach, duodenum or colon following oral administration to fasting or non-fasting mice. Nuclear aberrations were slightly increased in the duodenum of fasting rats receiving ferric chloride but not ferrous sulphate. In the colon nuclear aberrations were increased in fasting mice receiving oral ferric chloride and in fasting and non-fasting mice receiving oral ferrous sulphate. 

Following intrarectal administration ferric chloride showed greater toxicity to the colon than ferrous sulphate producing a slight but statistically significant (p<0.01) increase in micronuclei. Both iron salts increased the incidence of nuclear aberrations following intrarectal administration but this was more marked with ferric chloride.

The authors consider that the iron salts do not appear to have a significant genotoxic effect on the gastrointestinal tract and that the toxic effects are 

due to generalized toxicity rather than a genotoxic effect.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): negative
Ferric chloride has been tested in a study to examine the incidence of micronuclei in an assay using tissues from the gastrointestinal tract. The test substance is not considered to have a significant genotoxic effect on the mouse gastrointestinal tract as measured by induction of micronuclei. An increased incidence of nuclear aberrations was considered evidence of general toxicity.