Registration Dossier

Administrative data

Endpoint:
carcinogenicity: dermal
Type of information:
experimental study
Adequacy of study:
supporting study
Study period:
1997
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1997

Materials and methods

Test guideline
Qualifier:
no guideline followed
GLP compliance:
no

Results and discussion

Applicant's summary and conclusion

Conclusions:
DPD did not show Epidermal hyperplasia, Dermal cellularity, changes in 8-0H-dG/dGratio or mutations in codon 61 of Ha-ras and is therefore negative in this screening for carcinogenicity.
 
 
Executive summary:

The purpose of this study was to evaluate the ability of nine organic peroxides and hydrogen

peroxide to produce DNA damage (8-0H-dG formation,Ha-rasmutations) and sustained epidermal hyperplasia when administered to female Sencar mice topically twice weekly for four weeks.

 

The following methods were performed:

 

i. epidermal and dermal hyperplasia measurements and total dermal cellularity determinations measured at day 2 and day 4 after last dosing. Day 2 and day 4 measurements are necessary to judge only the inflammatory response, therefore all other parameters were measured on either day 2 or day 4 depending on availability of samples.

 

ii.8-0H-dG/dGratio determination by HPLC/ECD using DNA isolated from frozen skins.

 

iii. Mutations in codon 61 of Ha-ras using DNA isolated from paraffin blocks of whole skin.

Applied repetitively, to the dorsal skin of Sencar mice in doses of 4μmol/mouse.

 

DPD did not show Epidermal hyperplasia, Dermal cellularity, changes in 8-0H-dG/dGratio or mutations in codon 61 of Ha-ras and is therefore negative in this screening for carcinogenicity.