1,1-dichloroacetone

Carcinogenicity

Administrative data

Endpoint:

carcinogenicity: dermal

Type of information:

experimental study

Adequacy of study:

disregarded due to major methodological deficiencies

Reliability:

4 (not assignable)

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1989

Materials and methods

Test guideline

Qualifier:

no guideline followed

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

1,1-dichloroacetone

EC Number:

208-175-7

EC Name:

1,1-dichloroacetone

Cas Number:

513-88-2

Molecular formula:

C3H4Cl2O

IUPAC Name:

1,1-dichloropropan-2-one

Constituent 2

Reference substance name:

1,1-Dichloro-2-Propanone

IUPAC Name:

1,1-Dichloro-2-Propanone

Test material form:

not specified

Details on test material:

98 % purity

Test animals

Species:

mouse

Strain:

Sencar

Sex:

not specified

Details on test animals or test system and environmental conditions:

The test animals utilized were female SENCAR mice (Harlan Sprague-Dawley, Inc., Indianapolis, IN).

Administration / exposure

Route of administration:

dermal

Vehicle:

ethanol

Details on exposure:

Doses were applied six times ouer a 2-week period in 0.2 ml ethanol per application.

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

A constant dosing volume of 0.2 ml/
mouse was used for both topical and oral
administration. There were either 50 or 60
animals in each exposure group. Two weeks
after the last dose of the test chemicals, a
tumor promotion schedule involving application
of 1.0 pg of 12-O-tetradecanoyl-phorbol-
13-acetate (TPA) in 0.2 ml acetone 3 times
weekly was begun with either 30 (of groups of
50) or 40 (of groups of 60) mice and continued
for 20 weeks. The remaining 20 animals in
each group received 0.2 ml acetone only for
the same duration. The incidence of tumors
was charted by location and sized from weekly
observations. Papillomas were included in the
cumulative tumor count only if they were
observed for at least 3 consecutive weeks.
Only those animals surviving through 6 weeks
of promotion were included in the data analysis.

Post exposure period:

Groups of animals that were found to have
significantly increased incidences of papilloma
were maintained for a total period of 1 year to
allow for the development of carcinoma. At
the time of killing, all gross lesions were noted
and fixed in 10% buffered formalin and
tumors classified histopathologically.

Doses / concentrations

Remarks:

Doses / Concentrations:
600, 900, 2400, 3600, and 4800 mg/kg
Basis:
nominal conc.

Control animals:

yes, concurrent vehicle

Examinations

Statistics:

The percentage of animals with tumors in
each dose group was compared to the percentage
in the corresponding concurrent control
group using the likelihood ratio statistic.
The cumulative tumor count (tumors/animal)
was analyzed for a significant increase over the
concurrent control using the log rank test.
Results were deemed significant at the 0.05 a
level.

Applicant's summary and conclusion

Conclusions:

Among the five chlorinated acetone and three chlorinated acroleins and brominated
acrolein tested in the present experiments, only 1,3-DCA, CAC and BAC displayed activity
as tumor initiators in the mouse skin. 1,1-DCA did not induce tumors in the mouse skin.