A simple and general physical test of chemical carcinogenicity

149 80 Veljkovivi6, V., and D.I. Lalovi6, Boris Kidri5 Institute of Nuclear Sciences, Laboratory for Theoretical Physics, P.O. Box 522, 11001 Beograd (Yugoslavia) A simple and general physical test o f chemical carcinogenicity On the basis of theoretical and empirical considerations we have derived a simple and general criterion for carcinogenicity of organic chemical substances. Since the criterion uses physical parameters of original substances (not of their metabolites, which in many cases are the ultimate carcinogens) we have studied possible effects of metabolism on reliability of the criterion. We have concluded that in most cases metabolism does not effect our criterion. This conclusion has a direct bearing on estimation of relevance for man of carcinogenicity tests on mammalian systems. Namely, our criterion is semiempirical and based on results of carcinogenicity tests on mammalian systems. If we assume that difference in metabolism between man and other mammalian systems is the crucial point in estimation of the relevance for man of these tests, then, on the basis of our above-stated conclusion, it follows that results of carcinogenicity tests on mammalian systems are highly relevant for man.

81 Verschaeve, L., and C. Susanne, Laboratorium voor Antropogenetica, Vrije Universiteit Brussel, Brussels (Belgium) Genetic hazards o f mercury exposure in dental surgery In a foregoing study concerning the cytogenetic effects of mercury after occupationally low-level exposure we obtained data suggesting that a variety of mercurials have at first an important effect upon aneuploidy b u t may also induce chromosomal aberrations. Amalgams were also included in that study. These findings and the problem of mercury toxicity in relation to dentistry as discussed in the scientific literature inclined us to look at possible cytogenetic damage in the dental personnel. 10 Persons involved in the dental practice and 10 age-related controls were investigated cytogenetically (100 cells/person). A statistically significant increase of aneuploidy (and hypoploidy) was observed in the "dental group" in comparison with the controls. Chromosomal aberrations however were within normal values. The increase in aneuploidy which may be explained by the action of the mercury-amalgam upon the SH-groups of the spindle apparatus thus cannot rule out a possible health hazard to the dental personnel. Other factors however (like X-ray exposure) may be responsible for the observed data. A more thorough investigation seems to be necessary in order to come to more definite conclusions.

82 Weill-Thevenet, N.. M. Hermann and M. Hofnung, Institut Pasteur, Unit~ de Toxicologie G~n~tique, 28, rue du Dr. Roux, 75015 Paris (France)