Books
Cancer as a political issue The relationship between cancer and the environment has become one of today's pre-eminent and politically volatile issues. As the second leading cause of death in the U.S.—responsible for almost 400,000 deaths in 1978·—cancer clearly deserves attention. In the past, efforts to control cancer have concentrated on a traditional medical approach that emphasized therapeutic techniques. However, a growing body of evidence suggests that a more prudent course of action is cancer prevention. But to pursue this course, we must first answer the questions "What causes cancer?" and "How should we eliminate or control these causes?" At the outset of his book, "The Politics of Cancer," Samuel S. Epstein provides a partial answer to the first question. (Epstein is professor of occupational and environmental medicine at the School of Public Health, University of Illinois Medical Center, and is a long-time activist regarding possible toxic and carcinogenic hazards from industrial chemicals.) He states that "an informed consensus has gradually developed that most cancer is environmental in origin," and that "the recent increase in the incidence of cancer is due to industrial pollutants." He therefore maintains that there is already sufficient knowledge to prevent most cancer. Thus, Epstein's response to the second question is that the way to control cancer is to apply political action against industry to eliminate chemical hazards of pollution. Cancer, however, is an immensely complex disease process. Not only are there more than 100 distinct types of cancer, but each type may be influenced by a host of factors. These may include such diverse elements as living patterns, religious and cultural practices, dietary habits, exposure to background and man-made radiation or industrial chemicals, and sexual and reproductive patterns. Thus, to describe cancer in terms of environmental factors can quite literally mean all things to all people. If we are to attack the cancer problem successfully, we must further define those variables that are loosely called
Political action to control Industrial chemicals urged as primary method for fighting cancer "The Politics of Cancer," by Samuel S. Epstein, revised and expanded edition (paperback), Anchor Press/Doubleday, Garden City, N.Y., 1979, 628 pages plus xvii, $6.95; (hard cover) Sierra Club Books, San Francisco, 1978, 583 pages, $12.50 Reviewed by Elizabeth M. Whelan, executive director of the American Council on Science & Health and a research associate at the Harvard School of Public Health, and by Terrence Smith, a research associate at the council. The council was created by nonindustry scientists to present scientific information on controversial public health issues.
"environmental cancer risk factors." This is not an easy task. A number of risk factors are not fully understood. It is known that certain patterns of living or behavior may increase the probability of developing cancer, but it is not known what specific causative agent or agents, chemical or otherwise, are involved. For example, women who have their first child late in life are at higher risk for breast cancer than other women, but we do not know why. Similarly, it is suspected that some dietary factors influence cancer risk—particularly at such sites as the stomach, colon, prostate, breast, and uterus. Yet the specifics of this "environmental cause of cancer" are unknown. Despite the uncertainty that continues to impede cancer research, about 30 substances have been identified as causal factors in human cancer, in addition to some broad and ill-defined risk factors. To these, we must add another 200 to 300 chemicals that have caused tumors in laboratory animals. For these animal carcinogens, we must consider the
possibility of human risk, although at present we are unable to estimate the magnitude, if any, of human hazard. In terms of preventive strategy, current knowledge suggests that one of these chemical categories—tobacco smoke—contributes substantially to the overall cancer toll. It is estimated that cigarettes may account for as much as 35% of all cancers in males, and 80% of all lung cancers. Epstein, however, thinks the primary cause of cancer is not tobacco (although he does recognize its contribution), but rather "environmental chemicals"—particularly those found in the workplace and in air, water, and food. As he says repeatedly, there is no level of safe exposure to a substance that has been determined to cause cancer in either animals or humans. He recommends, therefore, a zero-tolerance philosophy and a commitment to eliminate potentially carcinogenic substances from the environment. Herein lies the heart of the cancer-prevention controversy. Epstein states that "the public has found, and scientists have to admit, that there are many subjective and judgmental decisions being made about cancer—its causes, prevention, and control. Many of these judgments, particularly when regulation comes under discussion, have little to do with pure science . . . it is vital that the public learn where the science of cancer ends and social policy considerations begin." Thus revealed, cancer is indeed a political issue. Should our society be willing to forgo the conveniences and benefits of such products as vinyl plastics, diet soda, or cured meats because they contain chemicals that have caused tumors under extreme conditions of experimental testing? Tobacco is the single most important cause of cancer in the U.S., yet an attempt to ban cigarettes would likely result in a debacle akin to Prohibition. Like all matters of politics, cancer prevention requires that we establish some priorities for action. John Higginson, director of the International Agency for Research on Cancer and one of the originators of the theory that most cancer is environmental in origin, has recently Jan. 28, 1980 C&EN
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Du Pont "Idea Intermediates'
Spark your R&D with these Polymeric Acrylonitrile Two forms—a homopolymer and a methyl acrylate copolymer—which yield water-soluble polymers, amines, esters.
Acrylonitrile CH21CHCN Good starting point for polymers and copolymers, and for amines through cyanoethylation reactions.
Acetonitrile CH3CN Highly polar, water-miscible, stable solvent for reactions, crystallizations and extractions.
Adiponitrile NC(CH2)4CN For mono or diester, acid or amine derivatives, or as a better general or aromatic extraction solvent.
2-Methyl-2-Butenenitrile ÇH3 CH3CH=CCN 2-Methyl-3-Butenenitrile CH3 CH2= CHCHCN Try these for improved polymers and new acid, ester, amine and other derivatives, or as solvents.
2-Pentenenitrile CH 3 CH 2 CH = CHCN 3-Pentenenitrile CH 3 CH=CHCH 2 CN These may offer attractive economies as solvents and for improving polymers, agrichemicals and other derivatives.
Methylglutaronitrile CH3 NCCHCH2CH2CN Versatile intermediate as well as solvent in uses such as aromatic extraction and gas scrubbing.
Hexamethylenediamine NH2(CH2)6NH2 For polyamide adhesives, plastics, inks; urethane coatings; scale inhibitors. Stronger base than ethylenediamine and most other primary amines.
PACM-20 NH2Y
VcH2Y
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Good starting point for plastics as well as adhesives, curing agents, chain extenders, other products.
2,4-Bis(p-aminobenzyl) aniline
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Low-cost chemical for making isocyanates, curing agents, adhesives, many specialty chemicals.
Methyl Benzoate/ Methyl p-Toluate C00CH3
C00CH3
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This ester mixture is a proven polyester dye carrier. Its also a promising coating solvent with both attractive solubility parameters and good evaporation characteristics.
Dimethyl Terephthalate coocHa
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coocH3
This diester leads to a variety of polymers and other products via transesterification, ammonolysis, ring substitution, reduction, reaction with Grignard reagents, hydrolysis, other reactions.
NH2
New Listing
commercially-available chemicals. Dodecanedioic Acid HOOC(CH2)ioCOOH Attractive raw material for polyes ters, urethanes, powder paint curing agents, synthetic lubricants, oil and gas additives, plasticizers, perfumes.
DBD Dibasic Acid Mixture HOOC(CH2)nCOOH n= 8 to 10 Mixed long-chain dibasic acids. Low-cost alternative for azelaic and sebacic acids.
Adipic Acid HOOC(CH2)4COOH Its still-growing application poten tial can make this established chemical a surprising 'new" material for you. In ample, reliable supply from Du Pont.
Dimethyl Succinate CH3OOC(CH2)2 COOCH3
Dimethyl Qlutarate CH3OOC(CH2)3COOCH3 These dicarboxylic acid esters have wide-range reaction potential. End-product possibilities include polyurethanes, polyesters, wetstrength resins, plasticizers, pig ments, synthetic lubricants, pharmaceuticals, perfumes, insec ticides, detergents and plant growth regulators, as a starting list.
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Cyclododecane
A large-ring cycloalkane of high purity. Its high boiling and freezing points suggest solvent applications. Possible raw material for musk-like products.
Cyclododecanol
