Biochimie, 69 (1987) 1113- 1115
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© Soci&6 de Chimie biologique/Elsevier, Paris
Book reviews
Chemical Carcinogens: Some Guidelines for Handling and Disposal in the Laboratory, 1986, Vol. 1, by M. Castegnaro and E.B. Sansone. Springer-Verlag, New York, Berlin, Heidelberg, T o k y o , pp. 97, b o u n d : DM 19.80 In the introduction of their monography, the authors Castegnaro and Sansone reproduce two lists of chemicals, industrial processes or occupational exposures which have been classified by experts from the IARC (International Agency of Research on Cancer) in group 1: as being causally associated with cancer in humans, and in group 2: as being probably carcinogenic to humans with different degrees of evidence. The authors discuss the risks related to the supply, the storage, the manipulation and transport of chemical carcinogens. They give suggestions to optimize the security of employees with regard to equipment and laboratories, from the wearing of a lab coat and gloves up to the conception of a high security lab from which no contamination should escape. The authors insist on the responsibilities at all levels involved by the use of cancerogenic substances. Nearly half of the book deals with the degradation methods of cancerogens and with the treatment of contamination by cancerogens. To be accepted, these methods must lead to non-toxic ar non-cancerogenic products, avoid exposure of the personnel and not contaminate the equipment or the environment. Incineration is recommended for the destruction of slightly contaminated big volumes. The authors mention that few studies have examined the effectiveness of incinerators which varies with several parameters and that it might be improved by equipping the chimney with low temperature catalytic systems. However, the authors note that such a degradation system is subjected to the risk involved by the transport of the contaminated waste to the incinerator. Castegnaro and Sansone then report the results obtained from a collaborative study from several laboratories on the destruction of 7 classes of chemical carcinogens (aflatoxins, nitrosamines, nitrosamides, polycyclic aromatic hydrocarbons, hydrazines, aromatic amines and haloethers) and of some antineoplastic agents. Their degradation was attempted in particular by different methods of oxidation (with sodium hypochlorite, a potassium permanganate/sulfuric acid mixture or chromic/sulfuric acid, hydrogen peroxide), by alcalin hydrolysis, denitrosation, reduction with Zn powder... Each method is discussed and for each class o.f cancerogen a table sums up the fields of application in preference
order for each accepted method. The use of these tables requires the parallel reading of the corresponding chapter. The tables and text are complementary to one another so that the reading of one without the other would be misleading. It should be noted that a given method cannot always be applied to all the products of a chemical class or may not be effective when some solvants are used. For example, oxidation by the potassium permanganate/sulfuric acid mixture is not adequate for some hydrazine derivatives. Similarly, denitrosation by hydrobromic acid can be slowed down by alcohol and strongly inhibited by water or dimethylsulfoxide. Some contradictions exist between the text and tables or within the text itself, for example, with regard to the degradation of polycyclic aromatic hydrocarbon by oxidation. Besides, the preference order of the degradation methods found in the tables does not always seem to correspond with what is indicated in the text. This book brings forward the frequent inability of sodium hypochlorite to degrade carcinogens effectively (nitrosamines, polycyclic aromatic, hydrocarbons, e.g.), and reveals that acidic permanganate which is often recommended, has nevertheless many drawbacks, that the very often efficient chromic/sulfuric acid mixture is systematically rejected for being toxic in itself. This study shows that there is no general recipe, but leads the way to search for an optimal degradation. It is supported by an extensive bibliography (193 references). It is to be regretted that this study which covers some 50 products does not include certain chemicals often used in laboratories such as ethidium bromide or diaminobenzidine. An analysis regarding the stability of the products and their solutions examined at different temperatures and different times of their degradation by physical methods (various radiations...) would have been welcome. Such methods, if effective, would considerably reduce exposure. In the impressive list given at the beginning of this book, dealing with products which are carcinogenic or suspected as such, it is surprising to notice that some chemicals are placed in the same group (progesterone and hydrazine, e.g.) with no particular information with regard to toxic doses or route of intoxication. Obviously, such a book could not cover all aspects. It is nevertheless a valuable contribution to scientists often confronted with problems regarding the use and elimination of cancerogens. Our congratulations to the authors. C.A. Komly and G. Michaud