Hydroxylammonium chloride

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

Study period:

Feb 1992

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1992

Report date:

1992

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)

Version / remarks:

adopted Jul 2016

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Bis(hydroxylammonium) sulphate

EC Number:

233-118-8

EC Name:

Bis(hydroxylammonium) sulphate

Cas Number:

10039-54-0

Molecular formula:

H3NO.1/2H2O4S

IUPAC Name:

bis(hydroxyammonium) sulfate

Test material form:

solid

Details on test material:

Name as mentioned in the report: Hydroxylammonium-Sulfat
Date of manufacturing: 04 Apr 1991
Test substance no.: 91/118
Appearance: white crystals
Purity: 98.6%

Test animals

Species:

mouse

Strain:

NMRI

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River GmbH, Sulzfeld, Germany
- Weight at study initiation: About 27 g (mean)
- Assigned to test groups randomly: Yes, according to a randomization plan prepared with an appropriate computer program.
- Housing: Animals were individually housed in Makrolon cages type M I.
- Diet: Standardized pelleted feed (Kliba Haltungsdiät, Klingentalmühle AG, Kaiseraugst, Switzerland), ad libitum
- Water: Drinking water, ad libitum
- Acclimation period: About one week

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 - 24
- Humidity (%): 30 - 70
- Air changes (per hr): Fully air-conditioned rooms
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

- Vehicle(s)/solvent(s) used: aqua dest.

Details on exposure:

PREPARATION OF DOSING SOLUTIONS: Dosing solutions were prepared immediately before administration by dissolving appropriate amounts of the test material in aqua dest. yielding a concentration of 12 g/100 mL, 6 g/100 mL and 3 g/100 mL, respectively. The volume of administration was 10 mL/kg bw.

ANALYSIS
For the determination of the test substance concentration in the solvent 3 samples per dose were taken from the test substance preparation using a stomach tube and transferred to test tubes. The samples were kept at room temperature until the treatment of the last animal (approximately 1 hour) and then deep-frozen until they were determined analytically. The determination of the concentration in the solvent was carried out .

The stability of the test substance in the solvent aqua dest. was determined analytically.

Duration of treatment / exposure:

not applicable

Frequency of treatment:

single treatment

Post exposure period:

300 mg/kg bw: 24 h after last treatment
600 mg/kg bw: 24 h after last treatment
1200 mg/kg bw: 16, 24 and 48 h after last treatment, respectively

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

300 mg/kg bw/day (nominal)

Doses / concentrations 2

Dose / conc.:

600 mg/kg bw/day (nominal)

Doses / concentrations 3

Dose / conc.:

1 200 mg/kg bw/day (nominal)

No. of animals per sex per dose:

5 (negative control and test group), 2 males and 3 females (cyclophosphamide), 3 males and 2 females (vincristine)

Control animals:

yes, concurrent vehicle

Positive control(s):

cyclophosphamide
- Route of administration: oral
- Doses / concentrations: 20 mg/kg bw
- Solvent: aqua dest.

vincristine
- Route of administration: intraperitoneal
- Doses / concentrations: 0.15 mg/kg bw
- Solvent: aqua dest.

Examinations

Tissues and cell types examined:

Tissue: bone marrow
Cell type: erythrocytes

Details of tissue and slide preparation:

CRITERIA FOR DOSE SELECTION: The maximum tolerated dose was selected based on results determined in a pre-test for the determination of acute oral toxicity.

TREATMENT AND SAMPLING TIMES (in addition to information in specific fields): Sampling was performed 16, 24 and 48 h after administration for the high-dose group and 24 h after administration for the mid- and low-dose group and the control groups.

DETAILS OF SLIDE PREPARATION: Smears were air-dried and first stained with in eosin and methylene blue solution for 5 min and thereafter in Giemsa-solution for 12 min.

METHOD OF ANALYSIS: 1000 polychromatic erythrocytes from each animal of every dose group were evaluated and investigated for micronuclei. In addition normochromatic erythrocytes were scored and investigated for micronuclei.

Statistics:

A statistical evaluation was not necessary to perform. The number of polychromatic micronucleated erythrocytes after test substance treatment was nearly in the range of the actual control value and within the historical values.

Results and discussion

Test results

Key result

Sex:

male/female

Genotoxicity:

negative

Toxicity:

yes

Remarks:

The highest dose level revealed evident signs of toxicity, such as irregular respiration, piloerection, apathy, abdominal position, closed eyelids and blueish skin within 30 minutes after test substance administration.

Vehicle controls validity:

valid

Negative controls validity:

not applicable

Positive controls validity:

valid

Additional information on results:

RESULTS OF RANGE-FINDING STUDY
- Dose range: In a pre-test for the determination of acute oral toxicity doses of 1250 and 1400 mg/kg bw were tested.
- Clinical signs of toxicity in test animals: Death occured at 1400 mg/kg bw. At 1250 mg/kg bw evident signs of toxicity were observed. Based on this pre-test the highest dose of 1200 mg/kg bw was selected in the main study for the determination of micronucleus.

Any other information on results incl. tables

Table 1: Summary of results

Treatment group	Dose [mg/kg bw]	Sampling time [h]	Polychromatic erythrocytes investigated	Normochromatic erythrocytes/total amount polychromatic erythrocytes	Cells with micronuclei (‰) in polychromatic erythrocytes	Cells with micronuclei (‰) in normochromatic erythrocytes
Vehicle control	0	24	10000	4271	1.6	1.17
Test substance	1200	16	10000	6428	1.2	0.16
	1200	24	10000	6561	1.0	0.46
	1200	48	10000	4560	2.7	0.22
	600	24	10000	4223	1.8	0.47
	300	24	10000	4906	1.3	1.02
Positive control (Cyclophosphamide)	20	24	5000	2997	8.8	1.33
Positive control (Vincristine)	0.15	72	5000	5789	103.8	2.07