US EPA

1035154 

Journal Article 

Preliminary studies in a quantitative approach to skin carcinogenesis 

Poel, WE; Kammer, AG 

1956 

Yes 

Journal of the National Cancer Institute
ISSN: 0027-8874
EISSN: 1460-2105 

16 

4 

989-994 

English 

13286713 

10.1093/jnci/16.4.989 

The carcinogenic response to cutaneous application of 3,4-benzpyrene (50328) was determined in mice. Individual uniform drops of 3,4-benzpyrene, obtained through the use of blunted hypodermic needles, were applied to the interscapular skin of male C57BL/6-mice 3 times a week. The concentration of 3,4-benzpyrene was varied from 0.01 to 1.0 percent, so as to vary the dose from 1 to 100 micrograms per application. Treatments were continued until animals developed a persistent skin tumor or died of other causes. All exposed mice developed skin tumors by 89 weeks of treatment. For doses of 1 to 50 micrograms per application, time preceding tumor appearance ranged from 29 to 10 weeks and was inversely related to dose. The length of the time interval during which all animals at a given dose developed tumors was greatest (64 weeks) at the 1 microgram dose and shortest (14 weeks) at the 50 to 100 microgram doses. The authors conclude that the potency of a skin carcinogen depends on dose and can be varied according to dose, provided the amounts involved do not exceed a saturation level. Previous experiments using brush painting techniques to apply test solutions have overlooked dose as a determinant of carcinogenic potency.