Strontium di(acetate)

Genetic toxicity: in vivo

Administrative data

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / bone marrow chromosome aberration

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

significant methodological deficiencies

Remarks:

Reliability 3 because there is no historical control, no positive control, effect on mitotic index unknown.

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1989

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Swiss albino mice of both sexes between 6 to 8 week of age and 30-32 g in weight.
Animals were bred under controlled temperature and humidity, receiving a commercial diet and drinking water ad Iibitum, without any supplementation with vitamins or antibiotics.
The animals were orally administered aqueous solutions of strontium chloride (SrCl2) in different concentrations. The LD50 was determined as 5200 and 4800 mg/kg body wt for males and females, respectively. The doses used were progressive dilutions of the LD50.
Five animals were sacrificed per set. Bone marrow cells were processed after each interval for chromosome studies following the usual colchicine-hypotonic-acetic ethanol fixation-flame drying Giemsa schedule. The slides were coded and scored blind for chromosomal aberrations. Fifty well-scattered metaphase plates per animal were analyzed for structural aberrations of chromosome that included gaps, breaks, centric fusion, and ring. About 3000 cells were scanned for mitotic index. The results were statistically analyzed following the 'Trend test'.
The different exposures were at 6, 12, and 24 h for each set according to the method followed by Preston et al. (previously published). The control was maintained on distilled water matched with the age and sex of the treated animal.

GLP compliance:

not specified

Type of assay:

other: clastogenic activity on bone marrow cells in vivo

Test material

Test material information

Constituent 1

Reference substance name:

Strontium chloride

EC Number:

233-971-6

EC Name:

Strontium chloride

Cas Number:

10476-85-4

Molecular formula:

Cl2Sr

IUPAC Name:

Strontium chloride

Test material form:

solid: crystalline

Remarks:

White crystalline solid

Details on test material:

CAS 10476-85-4

Test animals

Species:

mouse

Strain:

Swiss

Details on species / strain selection:

Swiss albino mice (Mus musculus L.)

Sex:

male/female

Details on test animals or test system and environmental conditions:

Mice of 6 to 8 week of age and 30-32g in weight.

Administration / exposure

Route of administration:

oral: feed

Vehicle:

distilled water

Details on exposure:

The animals were orally administered aqueous solutions of strontium chloride (SrCl2) in different concentrations. The doses used were progressive dilutions of the LD50.

Duration of treatment / exposure:

Oral administration at 6, 12 and 24h for each set.

Frequency of treatment:

Exposures at 6, 12 and 24h for each set.

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

260 mg/kg bw (total dose)

Remarks:

male group

Doses / concentrations 2

Dose / conc.:

866.6 mg/kg bw (total dose)

Remarks:

male group

Doses / concentrations 3

Dose / conc.:

2 600 mg/kg bw (total dose)

Remarks:

male group

Doses / concentrations 4

Dose / conc.:

240 mg/kg bw (total dose)

Remarks:

female group

Doses / concentrations 5

Dose / conc.:

800 mg/kg bw (total dose)

Remarks:

female group

Doses / concentrations 6

Dose / conc.:

2 400 mg/kg bw (total dose)

Remarks:

female group

No. of animals per sex per dose:

5 mice/sex/group

Control animals:

yes, concurrent vehicle

Positive control(s):

No

Examinations

Tissues and cell types examined:

Bone marrow cells

Details of tissue and slide preparation:

Bone marrow cells were processed after each interval for chromosome studies following the usual colchicine-hypotonic-acetic ethanol fixation-flame drying Giemsa schedule.
The slides were coded and scored blind for chromosomal aberrations.

Evaluation criteria:

Structural aberrations of chromosome (gaps, breaks, centric fusion, ring)
Mitotic index

Statistics:

The results were statistically analyzed following the 'Trend test'.

Results and discussion

Test results

Key result

Sex:

male/female

Genotoxicity:

positive

Toxicity:

not specified

Vehicle controls validity:

valid

Negative controls validity:

not applicable

Positive controls validity:

not applicable

Additional information on results:

Trend test value for chromosomal aberrations of mice fed strontium chloride (Z value):
6h : 6.184 (male), 6.67 (female)
12h: 5.209 (male), 6.725 (female)
24h: 6.797 (male), 7.689 (female)
All results have a p-value < 0.001 (significant results)

Applicant's summary and conclusion

Conclusions:

Strontium chloride has shown mutagenicity on bone marrow cells of mice.
Positive results was reported on strontium chloride in this study. However this result is considered as not reliable due to method deficiencies.