Carcinogen doses

Dash wood RH, Arbogst DN, Fong AT, Pereira C, Hendricks JD and Baily GS. 1989. Quantitative interrelationships between aflatoxin B1 carcinogen dose, indole-3-carbinol anto-carcinogen dose, target organ DNA adduction and final tumor response. Carcinogenesis 10 175-181. 

As mentioned above, the early studies of Kripke found that exposure to sub-carcinogenic doses of UV radiation suppresses the immune response of recipient mice and allows for the progressive growth of transplanted UV-induced regressor tumors.2 Adoptive transfer of antigen-specific T lymphocytes78could transfer the immune suppression to normal syngeneic recipient mice. 

Gehring, P.J. and Blau, G.E. (1977). Mechanisms of Carcinogenicity Dose Response. J. Environ. Path. Toxicol. 1 163-179. 

The important review by Druckrey and Preussmann and their coworkers (10) contains quantitative carcinogenicity data for more than 60 N-nitroso compounds acting on a single animal strain - the BD rat. In this study, the animals were administered a small daily dose of each N-nitroso compound, and the mean total carcinogenic dose (D q expressed as moles/kg body) required for production of tumors in 50% of the animals was then determined. Increasing values for D represent decreasing carcinogenicity. 

Boyland, R. and Hard, G.C. (1974). Early appearance of transformed cells from the kidney of rats treated with a single carcinogenic dose of dimethylnitrosamine (DMN) detected by culture in vitro, Europ. J. Cancer 10,177. 

Toth, B. Patil, K. (1982) A carcinogenicity dose response study by continuous administration of 1,2-dimethylhydrazine dihydrochloride in mice. Anticancer Res., 2, 365-368... 

At low carcinogen doses, there was effective inhibition of tumor development when the diet was supplemented with as little as 0.05% CLA. 

SIC Carcinogenicity Dose selection for carcinogenicity studies of pharmaceuticals Dose Selection for Carcinogenicity Studies of Pharmaceuticals Addition of a Limited Dose and related Notes CPMP/ICH/383/95 Step 5... 

Cranpton RF. 1980. Carcinogenic dose-related response to nitrosamines. Oncology 37 251-254. 

Toth B, Patil K. 1982. A carcinogenicity dose response study by continuous administration of... 

Fluorene. Fluorene has been reported to be negative as a complete carcinogen (dose not specified) (Kennaway 1924). This information was obtained from an old, secondary source and therefore, its reliability is not known. 

There was no evidence for a subthreshold dose for these carcinogens, since no deviation from linearity was recognizable even at the lowest carcinogenic dose level despite latency periods approaching the average life expectancy of the test species (2.5 years). 

To assess a carcinogen, doses are usually averaged over a lifetime and are presented as lifetime average daily doses (LADDs), even though exposure does not... 

Table 7. Effect of a carcinogenic dose level of lactofen on hepatic parameters in male CD-I mice (adapted from Butler et al. (80))...

Results of the Low Dose 2-AAF Study In order to experimentally assess the shape of the dose response curve at low carcinogen doses, the National Center for Toxicological Research undertook a study involving some 24,000 mice which were fed 2-AAF over a dose range of 5 to 150 parts per million. Two independent endpoints were monitored in the study, namely, the induction of bladder neoplasms and the induction of liver neoplasms. Animals were sacrificed at 18, 24, and 33 months into the study and the incidence of liver and bladder cancers was determined. Interestingly, two different types of dose response curves were observed (Figs. 7.2 and 7.3). 

Poel, W.E. Carcinogens and minimal carcinogenic doses Science 123 (1956) 588 Poel, W.E., D. Stanton, E. Peters, and H.O. Wade Approximation of a threshold-maximal carcinogenic dose range for 3,4-benz-pyrene when applied repeatedly to mouse skin Proc. Am. Assoc. Cancer Res. 4 (2) (1958) 333 Poel, W.E. and A.G. Kammer Preliminary studies in a quantitative approach to skin carcinogenesis J. Natl. Cancer Inst. 16 (1958) 989-994. 

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