The Statistical Analysis of a Carcinogen Mixture Experiment. III. Carcinogens With Different Target Systems,Aflatoxin B1,N-Butyl-N-(4-Hydroxybutyl)Nitrosamine,Lead Acetate,and Thiouracil

Abstract

This paper describes factorial experiments designed to determine whether two carcinogens that lead to cancers in different organ systems act synergistically to produce cancers in Fischer 344 rats. Four carcinogens, aflatoxin B₁ (AFLA), N-butyl-n-(4-hydroxybutyl)nitrosamine (NBBN), lead acetate (LA), and thiouracil (THIO) were studied in pairwise combinations. Each of the six possible pairs were studied by means of a 4 X 4 factorial experiment, each agent being fed at zero and at three non-zero doses. Methods of analysis designed explicitly for this study were derived to study interaction. These methods were supplemented by standard statistical methods appropriate for single agent studies. Neither synergism nor antagonism was demonstrated in these combined exposure studies. Findings for male and female animals were consistent.

Keywords

aflatoxin B1 lead acetate N-butyl-n-(4-hydroxybutyl)nitrosamine statistical analysis thiouracil.

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