2,4-dichlorophenol

Genetic toxicity: in vivo

Administrative data

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: LIterature report of a proprietary study. Awarded a reliability score of 2 in the source report.

Data source

Reference

Reference Type:

secondary source

Title:

Unnamed

Year:

2006

Report date:

1980

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)

Deviations:

not specified

Principles of method if other than guideline:

according to Boller et Schmid (1970 HumanGenetik 11, 35-54) and Schmid (1975 Mutation Res., 9-15)

GLP compliance:

no

Type of assay:

micronucleus assay

Test material

Test material information

Constituent 1

Reference substance name:

2,4-dichlorophenol

EC Number:

204-429-6

EC Name:

2,4-dichlorophenol

Cas Number:

120-83-2

Molecular formula:

C6H4Cl2O

IUPAC Name:

2,4-dichlorophenol

Test animals

Species:

mouse

Strain:

Swiss

Sex:

male

Details on test animals or test system and environmental conditions:

no data

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

Peanut oil

Details on exposure:

Immediately before dosing

Duration of treatment / exposure:

48 hour from first dose to sacrifice

Frequency of treatment:

Mice were dosed twice with a 24 hour interval between.

Doses / concentrations

Doses / concentrations 1

Remarks:

Doses / Concentrations:
0 mg/kg (vehicle only)
Basis:
actual ingested
gavage

Doses / concentrations 2

Remarks:

Doses / Concentrations:
160 mg/kg
Basis:
actual ingested
gavage

Doses / concentrations 3

Remarks:

Doses / Concentrations:
800 mg/kg
Basis:
actual ingested
gavage

No. of animals per sex per dose:

10

Positive control(s):

methylmethanesulfonate at 65 mg/kg, or cis-platin at 10 mg/kg by gavage

Examinations

Statistics:

students t-test

Results and discussion

Test results

Sex:

male

Genotoxicity:

negative

Toxicity:

yes

Remarks:

800 mg/kg/d produced severe prostration.

Vehicle controls validity:

valid

Positive controls validity:

valid

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): negative
2,4-dichlorophenol was negative in this in vivo mouse micronucleus assay.

Executive summary:

In a bone marrow micronucleus assay, Swiss mice (10/dose) were treated by gavage with 2,4-dichlorophenol at doses of 0, 160 and 800 mg/kg bw/day for 2 days (24 hours between doses).  Bone marrow cells were harvested 24 hours after the second dose.  The vehicle was peanut oil. The positive controls were methylmethanesulfonate  and cisplatin.

The only sign of toxicity was severe prostration at 800 mg/kg during the study.  2,4-dichlorophenol was tested at an adequate dose based on the signs of toxicity seen. The positive control induced the appropriate response.  There was no significant increase in the frequency of micronucleated polychromatic erythrocytes in bone marrow after any treatment time.

This study satisfies, as far as can be discerned the requirements for Test Guideline OECD 474 for in vivo cytogenetic mutagenicity data.