The aim of the editors of this volume is to use basic and ap­ plied studies in the field of mutagenesis to approach a problem of especial concern. The problem is that of the usage of toxic chemi­ cals, particularly agricultural chemicals, in ever-increasing quan­ tities in those parts of the world that feed the most people. Agri­ cultural chemicals that are in use in Pakistan are emphasized here. These are the same chemicals that are in use throughout the develop­ ing world, although the quantities of the different types that are used may vary from country to country, and from region to region within countries. A number of these chemicals can no longer be sold in Europe or in the United States, and it is often difficult to iden­ tify a scientific reason as to why they are sold at all. It is ironic that toxic chemicals are used as a humanitarian device to rid the world of Pestilence and Famine -- two of the Horsemen of the Apocalypse. If we do not wish poisonous chemicals to become the fifth Horseman of the Apocalypse, then we must begin now to identify and regulate the large-scale usage of toxic sub­ stances everywhere.

Inhalt

I. Introduction.- Welcoming Address.- Inaugural Address.- Toxins in the Human Food System.- II. Risks to Human Health Induced by Pesticides.- General Human Health Risks Associated with the Use of Chemicals.- Water Contamination and Environmental Mutagens.- Problems Associated with the Use of Chemicals by Agricultural Workers.- Mechanism of Contamination from Agricultural Chemicals in Mammals.- Mycotoxins as Carcinogens.- III. Basic Studies Related to Mutagenesis and Carcinogenesis.- Cytotoxicity as a Mechanism of Carcinogenesis.- Mutagenesis-Enhancement by Plasmids in Mutagenesis Tester Strains.- Situation-Dependent Repair of DNA Damage in Yeast.- A Possible Role for Deoxyribonucleotide Pool Imbalances in Carcinogenesis.- Polysubstrate Monooxygenases in Drosophila, Mammals and Man.- IV. Mutagenic, Teratogenic, and Predictive Carcinogenic Studies of Pesticides.- Evaluation of the Genotoxic Potential of Certain Pesticides Used in Pakistan.- Mutagen Testing of Agricultural Chemicals with Yeast.- Plant Genetic Assays and their Use in Studies on Environmental Mutagenesis in Developing Countries.- Aneuploidy Induced by Agricultural Pesticides: Where Do We Stand?.- The Science of Teratology in a Regulatory Setting.- V. Appendix I - Protocols.- Mutagen Testing with Yeast.- Mutagen Testing with Maize.- Mutagen Testing with the Soybean Assay.- The Micronucleus Test on Exfoliated Human Cells.- Mutagenicity Testing with Drosophila melanogaster.- A FORTRAN Program for the Construction of Selby-Olson Tables.- VI. Appendix Psticides Registered in Pakistan.- Agricultural Chemicals Registered for Sale in Pakistan.- Author Index.- Chemical Index.