Science writer Ruth Winter has produced a catalogue composed primarily of things not to buy; of naturally occuring but mostly man-made products which have been judged to be carcinogenic (cancer-causing) or mutagenic (affecting genetic material). An introductory chapter, describing her approach, discusses the value of epidemiological studies in cancer. What follows is an alphabetical listing from acetamide to zirconium lactate. While at times the writing smacks of handbook definitions, the overall result is a handy reference. You can check where we stand now on, say, DES (still allowed in meat) or on hair dyes and pesticides. Also included are entries such as bran, fiber, ozone, microwaves, ""the pill,"" and the like, summarizing the data concerning benefits or deleterious effects. Here, we encounter a variety of cancers where environmental factors are prominent, as well as several anti-cancer drugs which are now suspected of being carcinogenic themselves. Fiberglass comes up for mention, too, as--like asbestos--a potential threat to the lungs. Perhaps the most surprising information is under ""athletics,"" where it is noted that there appears to be a high cancer and cancer mortality rate among ""serious"" athletes such as college lettermen. (All very iffy, this.) On the whole the tone of the book is laudable, neither alarmist nor sensational. And, throughout, the nature of the tests, species, quantities of chemicals used, etc., are given so that the reader can weigh the evidence.