4-methyl-salicylamide

Genetic toxicity: in vivo

Administrative data

Endpoint:

in vivo mammalian cell study: DNA damage and/or repair

Remarks:

Type of genotoxicity: DNA damage and/or repair

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: see 'Remark'

Remarks:

Read-across from structurally similar compound. More information on read-across can be found in endpoint summary 7.6. Study published in a peer-reviewed journal, according to scientific standards. Experimental details well documented, no OECD guideline, no explicit reference to EPA OPPTS 870.5915.

Data source

Reference

Reference Type:

publication

Title:

No information

Author:

Giri AK, Adhikari N & Khan KA

Year:

1996

Bibliographic source:

Mutat. Res., 1996, 370, 1-9

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

EPA OPPTS 870.5915 (In Vivo Sister Chromatid Exchange Assay)

Deviations:

yes

Remarks:

BrdU tablets implanted 1 h before (not after) test substance administration. Only male mice tested (5 per dose) - no justification given. Room temperature of animal facilities unusually high (28°C).

GLP compliance:

not specified

Type of assay:

sister chromatid exchange assay

Test material

Reference

Name:

Unnamed

Type:

Constituent

Details on test material:

- Substance type: pure active substance
- Physical state: solid
- Supplier: Sigma Chemical Co, St. Louis MO, USA
- Analytical purity: no data

Test animals

Species:

mouse

Strain:

Swiss

Sex:

male

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Division of Laboratory animals, Central Drug Res. Institute, Lucknow, India
- Age at study initiation: 10-12 weeks
- Weight at study initiation: 30 g
- Assigned to test groups randomly: no data
- Fasting period before study: no
- Housing: five per cage, husk bedding
- Diet: Standard rodent pellet diet, Gold Mohor, Lipton India Ltd, Chandigarh, India (ad libitum)
- Water: ad libitum
- Acclimation period: no data

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 28 +/- 2 °C
- Humidity (%): 60 +/- 5 %
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): 12 / 12 hours

IN-LIFE DATES: no data

Administration / exposure

Route of administration:

other: intraperitoneal (3 dose levels); or oral (gavage) 1 dose level

Vehicle:

Vehicle(s)/solvent(s) used: DMSO (for i.p. application), suspension in 2% gum acacia in distilled water (for gavage application)
- Justification for choice of solvent/vehicle: solubility of the test substance
- Concentration of test material in vehicle: dose-dependent: approx. 10, 20, 40 mg/mL (i.p.), 35 mg/mL (gavage)
- Amount of vehicle (if gavage or dermal): DMSO 75 microliter/mouse for i.p., 2% gum acacia in water 0.3 mL per mouse for gavage
- Type and concentration of dispersant aid (if powder): 2% gum acacia
- Lot/batch no. (if required): no data
- Purity: no data

Duration of treatment / exposure:

i.p. administration: 23 hours, gavage administration: 23.5 hours
BrdU: 24 hours before sacrifice
colchicine: 2 hours before sacrifice

Frequency of treatment:

single treatment

Post exposure period:

none (time between administration and sacrifice: i.p. 23 hours, gavage 23.5 hours

Doses / concentrations

Doses / concentrations 1

Remarks:

Doses / Concentrations:
i.p. 25, 50, 100 mg/kg body weight
Basis:
nominal conc.

Doses / concentrations 2

Remarks:

Doses / Concentrations:
oral (gavage) 350 mg/kg body weight
Basis:
nominal conc.

No. of animals per sex per dose:

5 males per dose

Control animals:

yes, concurrent vehicle

Positive control(s):

mitomycin C
- Justification for choice of positive control(s): Preston RJ et al (1987) Mutation Res. 198: 157-165
- Route of administration: i.p. only
- Doses / concentrations: 1.5 mg/kg

Examinations

Tissues and cell types examined:

Bone marrow cells

Details of tissue and slide preparation:

CRITERIA FOR DOSE SELECTION:
i.p.: 1/10 of approx. oral LD50, since no i.p. LD50 available
oral/gavage: 1/3 of approx. oral LD50

TREATMENT AND SAMPLING TIMES ( in addition to information in specific fields):
- BrdU tablet (paraffin-coated, 80% of surface) implanted subcutaneously under anesthesia
- i.p. injection 1 h after tablet implantation, or gavage 1/2 h after tablet implantation
- colchicine (4 mg/kg) 22 h after tablet implantation
- sacrifice and expelling of bone marrow 2 hours later, i.e. 24 hours after tablet implantation

DETAILS OF SLIDE PREPARATION:
- hypotonic treatment: 20 min, 0.075 M KCl at 37°
- three times fixing with methanol / acetic acid 3:1
- differential staining of chromosomes on slide with fluorescence-plus-Giemsa technique

METHOD OF ANALYSIS:
- 30 second division metaphase cells (40 +/- 2 chromosomes) per animal scored for sister chromatid exchange SCE
- this is a total of 150 cells per dose scored
- randomly selected metaphase cells scored for replicative indices RI by staining pattern as first (M1), second (M2) and third (M3) division metaphases
- RI = (1*M1 + 2*M2 + 3*M3) / 100

Evaluation criteria:

Significant increase of SCE over control
dose-related increase
change in replicative index

Statistics:

Student's t-test, to compare results at each dose with control

Results and discussion

Test results

Sex:

male

Genotoxicity:

negative

Toxicity:

no effects

Remarks:

no mortality

Vehicle controls validity:

valid

Negative controls validity:

not examined

Positive controls validity:

valid

Additional information on results:

No significant increase in sister chromatid exchange (SCE) for all doses tested, when compared to solvent control.

No significant differences in replicative index (RI), when compared to control.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): negative
The test item is considered not genetic toxic in vivo. The study is considered reliable and can be used as part of read-across assessment.