Document 6bLOmw81KLQJwzb0RQ9mEadx6

An ACS Report ' *4 ' '' Cleaning our environment- the chemical basis for action This summary and recommenda tions are from the full report of the subcommittee on environmental im provement of the ACS Committee' on Chemistry and Public Affairs. The full report was released last week and precedes the various sym posiums at the ACS national meet ing this week in New York CityNational Forum on Environmental Quality--Air; National Forum on Environmental Quality--Water; In ternational Forum on Environmen tal Quality; and Monitoring of En vironmental Pollutants. The full re port is being sent to all Environmen tal Science and Technology sub scribers. Individual copies may be obtained from ACS special issue sales for $2.75 per copy. The Editors ACS Committee on Chemistry and Public Affairs William O. Baker, Bell Telephone Laboratories, Inc. Robert W. Cairns, Hercules, Inc. Theodore L. Cairns, E. I. du Pont de Nemours & Co. Herbert E. Carter, University of Illinois Lloyd M. Cooke, Union Carbide Corp. James D. D'lanni, Goodyear Tire & Rubber Co. Wililam E. Hanford, Olin Mathieson Chemical Corp. Milton Harris, American Chemical Society William F. Kieffer, College of Wooster Franklin A. Long, Cornell University Charles G. Overberger, University of Michigan Charles C. Price, University of Pennsylvania Glenn T. Seaborg, Atomic Energy Commission Joseph Stewart, Esso Research & Engineering Co. Calvin A. VanderWerf, Hope College Robert W. Van Dolah, U.S. Bureau of Mines Committee consultants Richard A. Carpenter, Library of Congress George B. Kistiakowsky, Harvard University k Committee staff Stephen T. Quigley, American. Chemical Society At the beginning of the study C. C. Price was the chairman; he was succeeded by F. A. Long. f 58 C&EN SEPT. 8, 1969 DSW 587987 STLCOPCB4093323 of Ethyl Corp,, Baton Rouge . . . Dr. Frank Brown, Jr., named senior organic chemist at Tippecanoe labs of Eli Lilly & Co., Lafayette, Ind. Dr. Nelson R. Easton promoted to associate director of research, Indianapolis. Dr. Gerald W. Probst promoted to director of regulatory services for Elanco Products Co. division ... Dr. Suresh N. Chinai named manager of acrylic fiber research at American Cyanamid's fibers division, Wayne, N.J. Dr. Joseph J. Pellon named manager of acrylic polymer research . . . B. G. Cleveland named sales manager for in dustrial division of Texize Chemicals, Inc., Greenville, S.C. . . . Sidney Danoff named v.p. for operations at Dexter Corp.'s Midland division, Waukegan, 111. . . . John A. Davidson named develop ment scientist at B. F. Goodrich Chem ical, Avon Lake, Ohio ... Karl W. Dieckmann promoted to general manager of dinnerware department fabricated products division of Allied Chemical . . . John C. Dorfler joins Quaker Chem ical, Conshohocken, Pa., as manager of process development. . . Harry M. Down ing, Jr., named director of technical service at Alpine Aromatics, Inc., Metuchen, N.J. . . . Dr. Edward Eaton joins staff of Kodak Research Labs, Roch ester, N.Y., as research associate. Martin Maslanger, Leslie Brooks, and Nancy Liebert join as chemists; Magdy Sifain and Robert Dickerson, as technicians; and Dr. Dale Conant and Dr. Donald McLaen as senior chemists . . . David H. Eilfort named to newly created position of chief counsel at Hitco, Los Angeles ... William A. Fletcher named Pacific sales representative for FMC Corp.'s or ganic chemicals division, Los Angeles .. . Peter Gentzsch named sales engineer by Lummus Nederland, N.V., The Hague . . . Ernest Gremell named Atlantic district manager of paints for Canadian Industries, Ltd. He continues as works manager at Halifax . . . John J. Grocki named manager of market de velopment-chemical for Penn Central Co., Philadelphia . . . Dr. Ata M. Hassan named research adviser in chemistry at Armstrong Cork's R&D or ganization, Lancaster, Pa. . . . Edwin H. Ivey, Jr., named general manager of Puerto Rico Olefins Co. . . . Peter D. Kviesitis named process engineer at Baxter Laboratories, Inc., Morton Grove, 111. . . . Dr. Charles E. Kwartler promoted to manager of process development for Ashland Chemical, Ashland, Ky. . . . Dr. William L. Madison named to newly created position of director, special prod uct development, McNeil Laboratories, Inc., Fort Washington, Pa. Dr. Michael J. Zelesko named senior scientist in chem ical research . . . M. Keith Nadel named manager of chemical division, med ical diagnostics operations, Xerox Corp., Pasadena, Calif. . . . Paul L. Nelson and Carl A. Street join sales staff of organic chemicals division, Emery Indus tries, Cincinnati . . . Dr. Christopher J. Panton transfers from Emeryville to Shell Chemical Co. in New York as senior technologist in petrochemicals division . . . E. J. Petranek promoted to newly created position of manager for special projects, chemicals division of Quaker Oats, Chicago. J. Fred Nelson succeeds him as manager at Omaha and John R. Ryan succeeds Mr. Nelson as superin tendent of the Memphis plant . . . Carol H. Pletcher appointed technical informa tion specialist in research information de partment of Parke, Davis & Co., Ann Arbor . . . John E. Pugalik and Larry L. Linton named Detroit and West Coast district managers, respectively, for Good year . Tire & Rubber chemical division. John R. Helwic transfers from Detroit to Dallas. Mr. Linton, who succeeds Roy B. Williams, will be headquartered in Los Angeles. Mr. Williams remains in Portland as sales coordinator. Richard H. Daly promoted to account manager, Philadelphia. James C. Brennan suc ceeds Mr. Linton as field sales representa tive in Memphis. Julius A. Lucas named general manager of Goodyear foam prod ucts division, Akron. Succeeds Frank R. Evans, retired after 43 years of service with the company . . . Daniel Raden named applications research chemist for . chemical marketing division of Abbott Laboratories, North Chicago, 111. . . . Robert Rager named market development specialist in phenolic products business section of General Electric's plastics de partment, Pittsfield, Mass. . .. Dr. Charles Schultz joins research laboratory staff of Chem-Trend, Inc., Howell, Mich. DEATHS Leason B. Adams, 60, supervisory com modity analyst in charge of natural chem ical products at U.S. Tariff Commission, Washingten, D.C., Aug. 7. Douglas G. Bennett, 53, manager of chemical sales at Phelps Dodge Refining Corp., New York City, July 19. Edmund B. Besselievre, 82, authority on water and waste pollution control, for merly consultant to Dorr-Oliver, May 28, Dallas. Published "The Treatment of In dustrial Wastes" early this year. Norris Boehmer, retired, formerly with Monsanto; April 10, Vero Beach, Fla. Joined ACS in 1918; emeritus member. Stewart K. Burr, 58, retired, formerly con trol chemist at Borden Chemical, May 17, Eugene, Ore. Joined ACS in 1951. John E. Caskey, 77, formerly v.p. of Uni royal, Inc., and general manager of its chemical division, Aug. 11, Naugatuck, Conn. Joined ACS in 1936. Dr. Herbert S. Harned, 80, emeritus pro fessor of chemistry, Yale University, July 29. Joined ACS in 1911. Dr. Leon H. Johnson, 61, president of Montana State University, Bozeman, June 18. Joined faculty in 1943 as associate professor of chemistry and became presi-' dent in 1964. Joined ACS in 1944. Frank Kovacs, formerly with Seiberling Rubber Co., Aug. 4, Milford, Conn. Joined ACS in 1919; emeritus member. Wilson D. Langley, emeritus professor of biochemistry and formerly chairman (1948-60) of department at University of Buffalo, Feb. 20. Joined ACS in 1920. Hugo E. Lahti, 54, formerly associate pro fessor of chemistry and industrial consult ant at Wisconsin State College, Fort At kinson, May 15. Joined ACS in 1952. Continued on page 71 alkenyl a succinic Q < O anhydrides O -J >ljD ouu o -j >LLI O LLI O < _l >LLI O ao i o >LLI O LLI O -J and a dozen others, plus the alkyl derivatives by I I i hydrogenation in the C> to Cm range. Specialty hy drocarbons, alkylbenzenes Q and alkylcyclohexanes. HUMPHREY CHEMICAL COMPANY North Haven, Connecticut 06473 DSW 587988 ;EPT. 8, 1969 C&EN 57 STLCOPCB4093324 This report grew out of conversations initiated late in 1965 by ACS's then-new Committee on Chemistry and Public Affairs with the Society's Division of Water, Air, and Waste Chemistry and its ad hoc Committee on Air Pollution. The Committee on Chemistry and Public Affairs saw in environ mental improvement an area in which it might perform the kind of specific public service that was its proposed mission. Since divisional programs and Environmental Science and Technology provide services largely for experts, it appeared desirable to produce a report aimed primarily at the involved and educated layman. To oversee the project the Committee on Chemistry and Public Affairs appointed four of its members as a subcommittee on en vironmental improvement. The Division of Water, Air, and Waste Chemistry recruited the task force of experts who worked directly on the project. In addition to those members of ACS who were intimately involved with pre paring this report, a number of other authorities, both members and nonmembers of ACS, provided comment and information; the authors have drawn also on the writings of many others. Fbanklin A. Long Charles C. Price Previous chairman Franklin A. Long Chairman Summary and Recommendations The 73 Recommendations distilled from the content of the full report and summarized here are designed both to exploit and to upgrade man's knowledge of his environ ment and of how to control it, particularly from a chemical point of view. That knowledge already is extensive. The science and technology of environmental control, despite many deficiencies, have advanced to a point at which this country can take enormous strides, now, toward a cleaner environment. The crucial requirement is that sufficient energy and support be devoted to the task. In the past few years, the nation has taken many of the legal and administrative measures required to clean up its environment. What is required now is a period of con certed attention to implementation of those measures. Ex isting science must be developed into usable technology; new and existing technology must be brought to bear on a wide scale on environmental problems. In short, the na tion's effort to improve its environment should be concen trated, for the present, on the use of existing science and technology. Emphasis on existing knowledge, however, should not be allowed to obscure the fact that extensive fundamental re search is required,to elevate man's understanding of the environmental system, in all its myriad aspects, to a more nearly adequate level than exists today. The need is clear in ecology, in analytical chemistry, in the effects of pol lutants, and in a number of other areas. Such research much be started now, if it is to provide the fundamental knowledge required for the new technology that will be needed in the not-too-distant future. It is critical, how ever, that this research be focused sharply on those areas where it will be truly effective. To provide such a focus is the intent of the recommendations in this report that call for further research effort. No one can doubt that cleaning up our air and earth and water demands the best efforts of many people from a variety of disciplines. The environment is a global system of almost infinite complexity. Any attempt to manage and control that system, moreover, must involve not only the pertinent science and technology, but the law, soci ology, politics, and economics as well. This document con cerns itself little with the management and nonscientific aspects of environmental control; others have examined them ably and at length. Nonscientific matters do, how ever, warrant attention here to the extent required to leaven the scientific and technological discussion with rea sonable perspective: _ In any such discussion nowadays die hand of the Federal Government is ubiquitous, both inylicitly and explicitly, and this is so for several reasons. To begin with, the en vironment is impure in large measure because society de mands the benefits of technology, and the practice of tech nology often generates pollutants. The individual acts against pollution, if he acts at all, in accordance with his DSW 587989 'EPT. 8, 1969 C&EN 59 STLCOPCB4093325 yi/e Lave had two goals in preparing this report. First, we have tried to set down an objective account of the current status of the science and technology of environ mental improvement: what is known and how it is being used; what must be learned and how it might be used. Second, we have analyzed the information thus assembled and have recommended a number of measures that, if adopted, should help to accelerate the sound development and use of that science and technology. We have focused strongly on chemistry, chemical engi neering, and the related disciplines. By so doing, we hope to expand die chemical awareness and flow of chemical know-how that are essential to any long-term rational ap proach to understanding and controlling our environment. We did not set out to inform experts, but if we refresh diem, so much die better. We do hope to buttress the tech nical awareness of legislators, administrators, and others who must deal with environmental problems at one or more steps removed from direct involvement widi dre per tinent science and technology. We hope also to attract the interest of those scientists and engineers not now involved in such problems who may have useful ideas and work to contribute to their solution. Lloyd M. Cooke own self-interest. This is fully as true of the man in the street as it is of the legal person called the corporation or of any government agency. People may rail at companies for making detergents that contain the algal nutrient, phosphorus, but how many families have switched from syndietic detergents to soap for that reason? Companies may rail at die acdons of pollution control officials, but how many companies have acted to abate pollution without some inducement in addition to the simple desire not to pollute, be it improved public relations, the possibility of profit, or threat of legal action? Self-interest is, of course, old to the affairs of men, and society deals with it gen erally, in the larger good, by striking a balance called the law. In matters of the environment, the range of self interests to be served is national in scope, and the basic law has thus come to be federal law. The environmental system, furthermore, is by nature thoroughly geopolitical. Air and water contaminants do not respect political boundaries. People drive their cars across state lines. Companies may manufacture in more than one jurisdiction; they may compete with companies who manufacture in one or more different jurisdictions. A given source of pollutants may be quite a different prob lem in a big city than in a rural area. Local laws and regu lations must reflect local problems, but they must also be grounded in basic legislation that applies equitably and effectively to all jurisdictions. Such legislation can be created best at the federal level. It should be noted also that air and water contaminants respect international political boundaries no more than they do state and local boundaries. The long-lived pesti cide DDT has been detected in wildlife in Antarctica, far from the unknown point at which it must have been ap 60 C&EN SEPT. 8, 1969 plied. The global concentration of carbon dioxide is changing, and the concentration of fine particles appears to be changing. Both could affect climate. A need exists ultimately, in fact, to consider international arrangements on environmental control. Reasonable stepping stones in clude programs such as the International Biological Pro gram and the United Nations conference on the human environment planned for 1972. The federal involvement extends beyond environmental control legislation. It includes the performance or support of certain types of research and development, environ mental surveillance and other types of data collection, and construction aid for pollution abatement facilities. Such projects generally encompass work that the profit-making corporation is not, by nature, designed to undertake on its own, and that state and local governments cannot afford. In the long run, the cost of pollution and its control will be borne by the citizen, in taxes and in the prices he pays for the products of technology. Cost, moreover, is prob ably the most powerful constraint that the nation must deal with in the near-term future. One can readily visualize costs in the range of hundreds of millions of dollars annu ally for controlling pollution by the automotive internal combustion engine alone. On that score, society in the U.S. has made a value judgment. It has. elected to pay, and is paying for control systems that will gradually reduce pollution by automobiles during the next half dozen years or so. A parallel value judgment underlies the establish ment and implementation of water quality criteria now going forward across the nation. In the area of solid wastes, on the other hand, municipalities have been largely reluctant to pay for the level of incinerator tech nology that the manufacturers can surely provide if the market demands it. Similar instances are not difficult to find. It is always possible that scientists and engineers will learn to recycle or dispose of wastes at a profit, but that does not seem likely to happen soon on a broad basis. If not fiscal profit, what is to be gained by investing huge sums in environmental control? Better health is to be gained. It is true that the relationships between human health and specific concentrations of specific pollutants are often tenuous today, and these relationships must be studied systematically at a fundamental level. It is equally true, however, that our population will increase, that our urban areas will expand, and that our ability to contami nate the environment will flourish in like measure. It is difficult to detect any promise of positive effects on health in this pattern of growth if it proceeds without environ mental controls. In addition to health, the money spent to manage the environment buys cleaner laundry in the back yard, longer life for the paint on houses, less corrosion and breakdown of electrical and other equipment. - It buys cleaner lakes and rivers for recreation. It buyst;relief from annoyance: a speck of ash in one's eye, unpleasant odors, yellowed foli age in the springtime. It buys nature as it ought to be, although it must be recognized that a modem industrial civilization and a pristine environment cannot coexist. Nature or, more broadly, the environment and the asso ciated phenomena constitute what has come to be called a system, and it is fashionable to speak of systems analysis DSW 587990 STLCOPCB4093326 as an almost magical route to the solution of many prob lems. Systems analysis can be indeed a powerful and necessary tool. It is vital to recognize, however, that die environmental system is made up of a bewildering number of subsystems that often are only distantly interdependent. The pollution problems of an electric power plant burn ing fuel oil are different from those of a plant burning high-sulfur coal, which in turn are different from those of a plant burning low-sulfur coal. The nutrient whose avail ability governs the proliferation of algae in one lake may be different from the governing nutrient in another lake. Environmental problems, in short, are rarely amenable to sweeping solutions; the benefits of even major break throughs in research are more likely than not to be limited to discrete subsystems of the overall system. Several problem areas emerge as explicit themes in this report. One such theme is the primitive condition of our fundamental knowledge of how living things are affected by long-term, low-level exposure to pollutants. Partly related to this theme is a second, the even more primitive condition of our knowledge of the effects of pol lutants on the ecology, that is, on the aggregate of living things as they exist together in nature. The relationship of contaminants to the ecology is very nearly a total mystery, and scientists are just beginning to study ecosystems on the multidisciplinary basis that is clearly required. A third theme is the analytical chemical methods that are used to monitor, control, and study the environment and related phenomena. Those methods generally are not as good as they ought to be. The technology that is used to monitor air pollutants, for example, is largely 10 to 20 years old. In contrast, scientists working with pesticides and radioactive substances recognized early the need for new and more discriminating methods and have made re markable progress in analytical chemistry in the past three decades. Similar progress is required today in many other areas of environmental science and technology where an alytical methods too often remain deficient. Among other problems in the field is the fact that the nomenclature is far from standardized. For this reason, and in the interest of broader understanding, the authors have minimized the use of specialized language. Of the special terms that do perforce appear, the most common are "contaminant" and "pollutant" and the corresponding verbs and adjectives. The tendency in the field is to regard as a "contaminant" anything added to the environment that causes a devia tion from the mean geochemical composition, the average composition that a particular phase of the environment would have in the absence of human activity. Thus con taminants are introduced by many natural phenomena-- forest fires, volcanic eruptions, collapsing river banks--as well as by nearly all human activities. A contaminant is considered a "pollutant" only if it can adversely affect some thing that man values and is present in high enough con centration to do so. These definitions cause a certain amount of confusion. Water vapor, for example, is scarcely considered a contaminant, but if it is added to the atmos phere by a large cooling tower in sufficient amount to be fog a busy highway it is clear]y a pollutant. Furthermore, the classification of a substance as con- Task Force on Environmental Improvement T. E. Larson, Illinois State Water Survey General Chairman A. P. Altschuller, National Air Pollution Control Administration Robert Ball, Michigan State University W. F. Barthel, U.S. Public Health Service Frances L. Estes, Gulf South Research Institute W. L. Faith, Consulting Chemical Engineer Melvin W. First, Harvard University David Hume, MIT William L. Klein, Ohio River Valley Water Sanitation Commission E. P. Lichtenstein, University of Wisconsin D. J. Lisk, Cornell University James P. Lodge, National Center for Atmospheric Research Louis Lykken, University of California, Berkeley Daniel MacDougall, Chemagro Corp. James J. Morgan, Caltech Daniel Nelson, Oak Ridge National Laboratory MaxS. Peters, University of Colorado Thomas J. Powers, Dow Chemical Co. Charles Renn, Johns Hopkins University R. L. Rudd, University of California, Davis Paul W. Spaite, National Air Pollution Control Administration W. M. Upholt, Federal Committee on Pest Control Foymae Kelso West, Gulf South Research Institute Philip W. West, Louisiana State University _ Richard Woodward, Camp, Dresser & McKee M. R. Zavon, University of Cincinnati Subcommittee Lloyd M. Cooke, Chairman Union Carbide Corp. William O. Baker Bell Telephone Laboratories, Inc. Arthur M. Bueche* General Electric Co. Franklin A. Long Cornell University * Term on Committee on Chemistry and Public Affairs expired Dec. 31, 1968. taminant or pollutant changes with time. If the substance is to be formally classified a pollutant, its effects must be perceived. Man's perception once was nearly limited to soiling of houses and laundry by soot. Scientists look now for subtle effects on the human lifespan, and they are be ginning to look for'even broader effects, such as modifica tion of regional and even global climate. In .the final analysis, all contaminants may well prove to be pollutants as well. By dictionary definition, the two words are in any case synonymous and are used interchangeably in this re port. -' ; Other special terms employed herein include "source," "sink," and "receptor." "Source" js the source of a pollu tant substance, such as a volcano dr agricultural runoff and drainage. `Sink" is the long-term, but not necessarily per manent, repository of a substance. The seas, for example, are a major sink for carbon dioxide, but they also release carbon dioxide to the air. "Receptor" is a living or non- DSW 587991 SEPT- 1969 C&EN 61 STLCOPCB4093327 living object on which a pollutant exerts its effect. Elec trical equipment corroded by nitrogen oxides in the air is a receptor. Although this report is scientifically and technologically far-ranging, it is not perfectly comprehensive. Topics that are not covered include thermal pollution, pollution by radioactive materials, and pollution by aircraft engine ex haust. The omission of such topics reflects the authors' arbitrary selection of a reasonable cutoff point, not the view that the problems involved are necessarily well under control. ' and more effort should be devoted to determining the na ture of the aerosols that cause such turbidity. Recommendation A2: The effects of carbon dioxide, turbidity, and other factors on climate should be studied in a sustained coordinated program designed to delineate clearly, if possible, the pertinent variables and their relative importance. Satellite measurements are particularly im portant here, if measurement technology can be developed. Recommendation A3: Research should be continued and selectively expanded on atmospheric reactions of many kinds. Such work should extend to measurements in the field in order to help relate the results of laboratoiy and sinog-chamber work to what actually happens in the urban and regional atmospheres. The ability to predict the flow of pollutants through urban and regional atmospheres, and the effects of pollu tants on air quality at points away from their sources, is still a developing science. The use of unique tracers, moni toring systems, mathematical models, and computers is far enough advanced to provide guidance in air pollution control and research, but full understanding of fundamental processes has yet to be achieved. Recommendation A4: The rates at which specific impor tant contaminants are removed from the air should be studied systematically on an item-by-item basis. Recommendation A5: Study of urban diffusion processes should be continued and selectively expanded, including coordinated use of long-lived tracers and work on optimum deployment and use of air monitoring instruments. THE AIR ENVIRONMENT Flow, dispersion, degradation Although considerable research has been done on the chemical and physical mechanisms of flow, dispersion, and degradation of substances in air, the knowledge of such mechanisms remains in large measure fragmentary. Knowledge of the sources and sinks of air contaminants is equally fragmentary. Contaminants spend variable periods of time between source and sink. Little is known of the factors that affect this time or that effect chemical and physical changes in contaminants along the way. The average time that contaminants spend en route is not evert known. For only one gas, carbon dioxide, are the data sufficient to demonstrate whether the gas's global concen tration is changing. Recommendation Al: Systematic measurement should be undertaken for a number of relatively long-lived substances in the general atmosphere, including carbon monoxide, nitrous oxide, methane, carbon dioxide, and sulfur hexa fluoride. The general turbidity of the atmosphere should be measured systematically on as wide a basis as possible, 62 C&EN SEPT. 8, 1969 Motor vehicles Emission control systems required on 1968 and later models of gasoline-powered vehicles, and the related re search and development programs now under way in the Federal Government and private industry, represent sig nificant steps in the control of automotive pollution. Con tinued surveillance of vehicles in normal use is required to determine the degree of control that actually has been achieved. Mandatory periodic inspection and maintenance of emission control systems is required to ensure their performance, but available procedures and equipment are not well suited to routine periodic inspection. Recommendation A6: Development of procedures and equipment by government and industry for periodic in spection of emission control systems in normal use should be stimulated to move ahead at the best possible rate. Recommendation A7: The development of improved in strumentation for measuring automotive emissions should be supported by all interests to a degree that will assure rapid progress in the ability to assess emissions in terms of both their amount and their reactivity in the atmosphere. The 1970 and 1971 federal standards for automotive emissions of hydrocarbons and carbon monoxide can be met with available technology. Any fufther reductions in allow able emissions, particularly if redaction of nitrogen oxides emissions were required, would necessitate more complex systems. The development of certain possible solutions to emission control problems is hampered by the presence of lead in gasoline. Recommendation A8: Federal emission standards more DSW 587992 STLCOPCB4093328 stringent than those to take effect in 1970 should be de veloped and promulgated at an early date so that auto makers will have sufficient time to develop the necessary control systems. Such standards should be designed to counteract the effects of the rising population of motor vehicles until at least 1980, and should include standards for nitrogen oxides. Recommendation A9: The effects of the lead compounds in gasoline on possible control systems of the future should be assessed carefully in terms of the emission levels that might be achieved icith and without lead, or with reduced amounts of lead, and in terms of the associated costs to the industries involved and to the consumer. Economic studies should include the relationship of lead to projected emis sion control systems, to the gasoline and lead additive manufacturing industries, and to the design and perform ance of the internal combustion engine itself. Advanced propulsion systems such as gas turbines, steam engines, and electric power are unlikely to have a signifi cant impact on automotive pollution for at least another decade. Of the three, electric power is the least advanced technologically for use in mass-produced vehicles of satis factory performance for the U.S. market. Work on public transportation systems that the public would find acceptable in the future is at an appallingly low level. Recommendation A10: The Federal Government should press its assessment of advanced, low-polluting power sys tems, including steam and electric power, to provide the basis for sound industrial research and development on such systems. . Recommendation All: Control agencies should be en couraged to establish procedures for on-the-road inspection of diesel-powered vehicles for compliance with smoke emission standards. Recommendation A12: More attention should be given to the development of acceptable means of public transporta tion. Industrial facilities Improvements have been made and are being made in air pollution control in industry, but the general situation is growing worse because of instances of failure to apply existing control technolog)'-, growth of industry', and lack of economic technology in some cases. In the absence of federally established air quality criteria, and the consequent air quality standards, industry often finds it impractical to select and apply the necessary con trol methods. As of early 1969, the Federal Government had established criteria only for sulfur oxides and particles, although work is in progress on criteria for other air con taminants. Recommendation A13: The promulgation of air quality criteria by the Federal Government should be supported in a manner that will allow it to proceed with all possible speed. Effective and economic control equipment for many in dustrial emissions is available and is being used widely. Design of such equipment is frequently empirical, and a more fundamental understanding of the physical and chemical phenomena involved could produce benefits in performance. " Recommendation A14: The development of new and im proved control technology and equipment for industrial emissions must be stimulated, particularly for types of in dustries for which economic means of control do not now exist. Low-cost equipment for small industries is particu larly essential. Recommendation A15: More research and development should be undertaken on nonpolluting alternative manu facturing processes, where appropriate, and on the utiliza tion of materials recovered by pollution control equipment, where such equipment must be used. The recommendations for utility' power plants, which follow, are also pertinent to industrial power generation. Utility power plants Abatement of sulfur oxides emissions from utility power plants nationwide has not yet started to a significant de gree, except in a few large metropolitan areas that are re quiring that low-sulfur fuel be used. Abatement will re quire the use of a variety of methods: low-sulfur fuels, stack-gas cleaning, and the tall stack. Recommendation A16: Translation of federal air quality criteria for sulfur oxides and particles into air quality standards should proceed rapidly so as to speed widespread application of the available means of controlling these emis sions. - Recommendation A17: Existing research to define the overall effectiveness of the tall stack in meeting air quality standards should consider the effects of mass emissions of pollutants not only on local, ground-level concentrations, but on the local and regional air masses and on ground-level concentrations outside the local area. Recommendation A18: Investigations of techniques for desulfurizing fuels must be carried to the point where economic evaluation is possible. Particularly desirable would be early definition of the amounts and locations of coals that can be cleaned economically of significant amounts of pyritic sulfur. The development of economical coal cleaning processes is a responsibility of the coal in dustry, and more comprehensive studies should be made than have been made in the past. Further research appears to be required on hydrodesulfurization catalysts that are not deactivated by the heavy metals in residual fuel oils. Recommendation A19: The development of first-genera tion processes for removing sulfur oxides from utility stack gases should be supported and stimulated so as to achieve early commercialization, particularly in order to offer a control option for existing power plants. Research and de velopment on new and original methods of removing sulfur oxides from utility stacks should proceed rapidly to the point at which specific processes can be selected for ad vanced development. Technology is not available for achieving significant re duction of nitrogen oxides emissions, by utility power plants nationwide. Reduction can be achieved in some plants by changes in design. Reduction ha^ also been achieved by using natural gas as fuel, but gas does not consistently show an advantage in this respect. Recommendation A20: Current studies of nitrogen oxides emissions by stationary sources should define the economics and effectiveness oJ modifvine existing power plants, where DSW 587993 r- e- 1969 C&EN 63 STLCOPCB4093329 possible, or of using alternative fuels to reduce such emis sions. Recommendation A2-1: Research and development on new combustion processes should include pollutant emissions as a basic parameter. Space heating The use of low-sulfur fuels and efficient combustion equipment for space heating can significantly abate urban emissions of sulfur oxides and particles. Contaminants can not be removed practically from stack gases produced by space heating units except where energy is produced centrally in large units and distributed to the point of use. Recommendation A22: In its development of national fuels policies and inventories, the Federal Government should take proper account of the needs of present and develop ing urban areas for low-pollution fuels for space heating. Recommendation A23: Federal and state governments should ensure that objective and up-to-date technical in formation on the most efficient combustion equipment for space heating is available to municipal authorities. Recommendation A24: The economics of centralized pro duction of heat for space heating should be re-evaluated. Such studies should consider the distribution of energy in the form of hot air, electricity, steam, or high-temperature water (400F and 274 psi). Effects of air pollutants Air pollution is clearly undesirable. Incidents have oc curred of lethal accumulation of pollutants, and all pollu tants are known to have catastrophic effects as sufficient concentrations. Typical urban concentrations are not acutely lethal, but it is difficult to argue that their lesser concentrations make them harmless. Recommendation A25: Epidemiological and laboratory studies of the effects of air pollution on humans, including model experiments on animals, should be carefully co ordinated and selectively accelerated. Body burdens and environmental levels of potentially harmful metals should be monitored insofar as is feasible on a systematic and continuing basis. Knowledge of the effects of air pollutants on vegetation is represented largely by studies of acute damage to tissue. Information is limited on reduction of crop growth and productivity and on mechanisms of action. The effects of air pollutants, on many materials are reasonably well understood, but it is difficult if not im possible to attach an economic value to the damage, ex cept in specific instances. Recommendation A26: Economic and. scientific research on the effects of air pollutants on vegetation and materials should be maintained at a level in consonance with work on effects on humans. The relationship of air contaminants to the ecology at the current state of knowledge can only be surmised. Recommendation A27: A concerted research program on the ecological effects of air pollutants should be developed and carefully coordinated as: a multidisciplinary effort. Recommendation A28: Better experiments must be de- 64 C&EN SEPT. 8, 1969 signed to evaluate the intangible effects of polluted atmos pheres, such as annoyance by odors, loss of scenic views, depression at loss of sunlight, arid limitations on photosyn thesis. Recommendation A29: The establishment of federal air quality criteria, and their continued revision in the light of new evidence, is essential to rational management of the air environment. The effort should be continued at a pace commensurate with the development of knowledge, and the succeeding steps under the federal Air Quality Act of 1967 should be taken as expeditiously as possible. Analytical chemistry and instruments The methods and equipment used in air monitoring systems today are providing useful data, but must be sharply improved. The methods and equipment used to monitor emissions continuously at the source, either in stack or remotely, also require improvement. Progress is required, moreover, in standardization of analytical meth ods, both to establish their reproducibility in the hands of chemists in different laboratories and to help to optimize them. Recommendation A30: Development of simplified, less costly instrumentation for air monitoring should be ac celerated markedly, gleans should be found for stimulat ing industrial research and development in this area. Recommendation A31: The development of better in-stack and remote source-monitoring instrumentation for pol lutants is essential and should be accelerated. Federal stimulation may be necessary to achieve adequately rapid innovation and dissemination. Recommendation A32: Standardization of analytical methods and instruments should also be accelerated. Such standardization should include criteria for acceptable meth ods of sampling and storage as well as for the analytical methods themselves and for the interpretation and use of the resulting data. A program should be considered for certification of air-monitoring instruments on the basis of federally established standards of performance. Recommendation A33: Current levels of effort in develop ing new and improved analytical methods for pollutants should be increased. Such methods constitute the input from which monitoring instruments are developed. Ana- lytical methods should not be downgraded solely because they are not adaptable to automatic instrumentation. For some tasks, such as exploratory studies of air pollution, manual methods may he much superior to automatic instru ments. - THE WATER ENVIRONMENT ` Flow, dispersion, degradation Knowledge of the specific chemical compounds in waste streams and in natural waters is, generally inadequate to support quantitative understanding of the flow, dispersion, and degradation of water pollutants. Data on the magni tude of waste streams from all significant sources are also far from adequate. 1 Recommendation Wl: Regional inventories, on a selective trial basis, should be made of pollutants from all sources that are known or expected to be important. An effort . DSW 587994 .. STLCOPCB4093330 should be made to learn more of the specific chemical com pounds, particularly organic compounds, that are present in both wastes and natural waters. Chemical and biological research on natural waters, polluted or not, should be emphasized. ' General descriptions of the remarkably complex be havior of natural populations of micoorganisms in natural water environments are unlikely to emerge. Research on the role of microorganisms in pollutant transport, includ ing biological degradation, must include knowledge of specific chemical compounds and measurement of their degradation products. More and more, the collective chemical parameters now in common use will prove inade quate for understanding the behavior of complex natural systems. Recommendation W2: Fundamental research should be expanded on the action of natural mixed populations of bacteria and other organisms on specific compounds. Such research will require the development of analytical meth- ods for identifying and quantifying specific compounds produced by biological degradation. Data on the size distribution arid chemical, physical, and biological properties of particles in waste waters and natural waters are much too sparse to allow useful assessments of the role played by particles in pollutant transport. Recommendation W3: Comprehensive investigations of naturally occurring and pollutant particles in water should be undertaken to determine such characteristics as size, charge, composition, and adsorptive properties. Expanded knowledge of particles would be important in studies of sedimentation, erosion, and certain waste treatment processes, as well as in work on transport. Intelligent management of the water environment in the long run must rely in part on the use of mathematical descriptions of natural water systems subject to pollution, but the chemical-biological complexity of those systems continues to defy attempts to describe them mathematically. Good progress has been made in describing the physical processes of convection and dispersion, and the main uncertainties now in describing pollutant transport mathe matically appear to lie in the degradation processes. A more specific problem is the lack of knowledge of the mo lecular nature of substances as they exist in water. Recommendation W4: Research on improved mathemati cal descriptions of natural water systems subject to pollu tion should be strongly supported. The chemical-bio logical complexity of those systems requires that such re search be highly interdisciplinary, involving scientists from disciplines such as chemistry, chemical engineering, civil engineering, biology, and ecology. Sheer complexity may ultimately limit the generality of the mathematical de scriptions that can be developed, but it is essential to find a proper balance between the difficulty of understanding natural water systems and the need to describe them mathe matically. - Knowledge of pollutant transport in soil and ground water is growing more important because of the trend toward recharging ground waters with treated waste waters. Gaps remain, however, in the fundamental under standing of how the soil functions as a filter and biological medium and, more particularly, in the ability to exploit the available fundamental knowledge of the soil system. Recommendation W5: Systematic studies should be en couraged on the flow and reactions of fonns of phosphorus and nitrogen, and various organic substances, in soil and ground water. Recommendation W6: More emphasis should be placed on investigation of the transport and long-term deposition of pollutants in the oceans, lakes, and deep underground for mations. The initial requirement is improved analytical methods for identifying and measuring specific chemical compounds. Municipal waste water treatment Conventional primary-secondary treatment of munici pal waste waters is cheap and effective, to a point, and there is at present no adequate substitute for it. However, the performance of conventional treatment plants has been measured and controlled traditionally in terms of collective parameters, such as biochemical oxygen demand. These collective measurements do not produce the specific data, such as the fate of specific organic compounds in the treat ment process, that are required to develop meaningful general interpretations of the biochemical and biological aspects of conventional processes. Thus reliance on col lective parameters, though useful in process control, has resulted in a severe shortage of the specific data required, particularly at the operating level, to work toward optimiz ing conventional processes. Recommendation W7: Biochemists and biologists should become more involved in research on sewage treatment, primarily to seek radical innovation}, based on fundamental understanding of microbiological processes. Emphasis should, be laid on the use of adequate chemical tools to develop data that will allow the biochemical and biological aspects of treatment processes to be interpreted more mean ingfully and that can be used in process optimization. DSW 587995 sept. 8.1969 c*en 65 STLCOPCB4093331 Handling and disposing of the sludges from conventional processes is the leading technological problem in waste water treatment today. New and more efficient methods are required. The use of synthetic polymers to improve flocculation and sedimentation of sludges and to condition them for dewatering is very promising, but knowledge of the fundamental process parameters falls short of what is needed to exploit polymers fully for these purposes. Recommendation W8: Research should be expanded on new methods of handling waste water treatment sludges and on the fundamental process' parameters involved in using synthetic polymers and polyelectfolytes and other novel surface-active chemicals to improve flocculation, sedimentation, and conditioning of such sludges. Com prehensive data should be developed on the economics and technology of complementary and/or alternative means of sludge disposal, such as incineration, use as fertilizer or soil conditioner, underground disposal, and pipeline transportation. Recommendation W9: Systematic studies should be undertaken of the quality of urban storm waters to provide a sound base for assessing alternative means of treatment. Advanced waste treatment A number of advanced waste water treatment processes are in development, several are at the pilot-plant stage, and one full-scale demonstration plant is now operating that integrates several such processes into a single water reclamation system. Comprehensive operating and eco nomic data at the commercial level are not yet available for most advanced waste treatment processes. Recommendation W10: Chemical and biological charac terizations should be made of advanced treatment systems operating at the large pilot-plant or demonstration-plant level, including the identification of specific chemical com pounds, studies of the effects of chlorine or other oxidants on organic residues, and other necessary investigations. Such studies should be comprehensive research and de velopment efforts, not simply demonstrations that the sys tems operate properly in terms of the traditional param eters. Recommendation Wll: Adsorbents other than activated carbon, such as inorganic oxide systems, should he con sidered further for advanced waste treatment. There ap pears to be no inherent reason to restrict adsorption processes to activated carbons not designed specifically for the chemical species in waste waters. Further knowl edge of those species might allow improved adsorbents to be synthesized. Recommendation W12: Research should be maintained at a high level on removal or inactivation of viruses by waste water treatment processes and on other means of pre venting virus buildup in recycle systems. Industrial facilities Much of the conventional treatment technology for municipal waste waters applies also to industrial waste waters, and a trend appears to be developing toward more joint use of treatment facilities by industry and municipal ities. Industrial waste water treatment is certain to be 66 C&EN SEPT. 8, 1969 _ come more extensive because of the general move toward providing the equivalent of secondary treatment. In creased use of joint facilities might ease the overall eco nomic burden of such treatment, as reflected ultimately in the prices of products and services. Data on the specific substances contained in industrial waste waters do not appear to be adequate to support rational assessment of their pollutant potential or the development of regional inventories of important or po tentially important pollutants. Recommendation W13: Information should be gathered and made widely available on the technology of joint municipal-industrial treatment of waste waters for the guidance of companies and municipalities that wish to con sider such an approach. This task should be managed at the federal level. Recommendation W14: Inventories should be made, on a selective trial basis, of the specific substances in industrial waste icaters that are important or potentially important pollutants. This task should be managed at the federal level. Nonmunicipal, nonindustrial water pollution Known sources of water pollution other than conventional municipal and industrial sources are not always identified or well delineated, and control technology is often weak or nonexistent. Agriculture is a major source of potential water pollutants and presents difficult problems in developing both basic data and means of control. Perhaps the greatest source of pollution by agriculture is soil transport in runoff due largely to failure to apply soil conservation practices. This results in transport of pesticides on soil particles to streams, development of high suspended solids and turbidity, and high sedimentation rates in lakes and reservoirs. The in efficient use associated with the rapid rate of increase in use of fertilizers is becoming alarming in some parts of the country. Recommendation W15: Basic research should be en couraged on economic means of treating and disposing of animal wastes in agriculture. Recommendation W16: Basic data should be gathered systematically to delineate the relative importance of the various agricidtural and rural sources of compounds of nitrogen and phosphorus in surface waters and ground waters. Effects of water pollution The main concern over the effects of water pollutants on human health at present lies in the effects qf Jong-term, low-level exposure. Relative to this kind of exposure, very little is known of the possible effects on human health of the variety of largely unidentified chemical compounds that enter sources of water supply. i Recommendation W17: Research should be strongly en couraged on the effects of known\water pollutants in long term, low-level exposure. Both laboratory and epidemio. logical work will be required. Studies of the behavior of viruses in existing water re-use systems and their movement in soil and ground waters have been remarkably few. It is difficult to evaluate the sound DSW 587996 STLCOPCB4093332 ness of certain water re-use schemes without knowing more of the potential for viral disease. Recommendation W18: Studies should be maintained on enteric viruses and their movement in soil and ground water. There is no significant epidemiological basis for the total coliform bacteria counts used today to establish standards for body-contact recreational waters. Recommendation W19: Correlations of bacterial indicator organisms with waterborne disease, particularly in recrea- tional'waters, should receive high priority. Not as much is known as should be known of specific compounds in waste treatment plant effluents. Accidents, negligence, and disasters do occur. Water treatment tech nology and normal treatment capacity are not necessarily adequate to cope with unknowns, sudden pollution loads, and man-made or natural disasters. ' Recommendation W20: Public water supply treatment methods should be upgraded through research on removal and destruction of potentially harmful substances not re moved by waste treatment practices, or bypassed with in sufficient dilution during plant outage periods or in times of disaster such as power failures. Knowledge of the fundamental processes involved in eutrophication is well below the level that will be required to develop sound, long-range control measures. The cur rent emphasis on removal of phosphorus from waste waters should be tempered by the realization that the effectiveness of the measure may not be known for some years. Recommendation W21: Investigations should be pursued of the fundamental chemical and biological parameters of eutrophication and its effects. Development of effective and economic long-term controls will depend on consider ably improved knowledge of factors such as mass balances for significant nutrients; the forms in which those nutrients exist in water; natural population dynamics; potentially limiting nutrients in specific situations; and algal, bacterial, and plant physiology in general. Municipal refuse SOLID WASTES The technology is available to sharply upgrade the han dling and disposal of municipal refuse in the U.S., but it is being applied only to a very limited extent. Recommendation SI: The appropriate federal, state, and local government agencies should press their efforts to de fine the nature and magnitude of the solid wastes problem both now and in the future. Education, research, and demonstration, and local and regional planning for solid wastes management, utilization, and disposal are all neces sary for progress in this neglected area. - Sanitary landfill and incineration, when properly de signed and operated to prevent ground water and air pollu tion, have both been demonstrated to be effective, nuisance- free means of disposal from which positive values can be obtained in the form of reclaimed land and waste heat. Composting has succeeded economically in only a few in stances, but it has yet to be put on the kind of scientific basis that will allow its general potential to be assessed definitively. Recommendation S2: The use of known peripheral sci ence and technology in developing improved methods for sanitary landfill and incineration should be encouraged and supported. Efforts to develop a more scientific basis for composting should also be supported, particularly in the area of the biochemistry and related aspects of the degrada tion process, so that the potential of the method, which ap pears to date to be quite limited, can be assessed more definitively. Analytical chemistry and instruments Research on eutrophication, potentially toxic pollutants, tastes and odors, and other aspects of water pollution would be eased by the development of improved analytical meth ods and procedures for low levels of phosphorus, nitrogen, trace metals, and trace organic compounds. Recommendation W22: Emphasis should be placed on the development of analytical methods for specific organic pollutants at all concentrations and in all waste sources and receiving waters, including estuaries and the oceans. Simi lar effort should be devoted to developing methods for low levels of phosphorus, nitrogen, and other nutrients that are involved in eutrophication. The evaluation and standardization of analytical chem ical methods has not kept pace with the need engendered by progress in water pollution research and control. Eval uation should include sampling methods and changes in composition during transport and storage. Recommendation W23: Analytical methods for gathering basic data, monitoring, research, and treatment control should be actively and continuously upgraded by systematic evaluation and standardization. STLCOPCB4093333 Recommendation S3: Research and development on utili zation and recycle of components of municipal refuse and incinerator residue should be maintained at a level that will ensure that radically new approaches are not overlooked or inadequately investigated. Recommendation S4: Continuing attention should be paid to collection and transportation of municipal refuse, both in the development of improved technology and in mecha nisms for promoting the application of such technology by local agencies that are responsible for handling and dis posing of municipal refuse. Junked automobiles Disposal of discarded vehicles appears to be largely a problem of applying technology to produce a marketable scrap at a cost that can be borne by scrap processors. Im portant factors are the costs of transportation, of the re quired processing equipment, and of air pollution control equipment. Recommendation S5: Efforts by private industry to im prove the economics of the auto scrap processing industry should be stimulated. The development of scrapping methods that would permit the use of less Costly equipment, and of radically new scrapping methods, should be pursued at all levels. The development of new means of utilizing junked vehicles should also be encouraged and supported, with emphasis on methods of recycling the metals. Industrial solid wastes Large amounts of the materials of production are re cycled both in-plant and as secondary materials and dius never become true solid wastes. Recommendation S6: Efforts to improve the economics of recycle of solid materials by the secondary materials in dustry should be encouraged. A distinction should he maintained betioeen solid materials that are recycled and those that are true solid wastes. A time may be approaching when industry will find it economical to burn more of its own solid wastes than to dis pose of them in on-site landfill or to hire outside contractors to remove them. Recommendation S7: Studies should be made of the chemical and physical nature and the volume of industrial solid wastes, insofar as proprietary problems allow, in order to support the conception and design of equipment, in cluding incinerators, for disposing of them economically. level against the day when changing economics warrant the recovery of such minerals. Work on other means of utilizing or disposing of these wastes should also be main tained at a steady level. Effects of solid wastes A well-defined relationship between solid wastes and human health has not been demonstrated under the con ditions that prevail in the U.S., although it is possible to conclude that, for some diseases, a relationship exists. The more obvious effects of solid wastes include the esthetics problem and pollution of air and water by improper means of disposal. Recommendation S9: The effort to upgrade solid wastes management, utilization, and disposal should be justified on the basis of esthetic values and control of air and water pollution. - PESTICIDES IN THE ENVIRONMENT Pesticide residues in soil, water, and air More detailed information is available on pesticide resi dues in the environment than for most other contaminants. This is due primarily to the excellence of analytical methods for the determination of minute amounts of pesticides. Most pesticides are biodegradable and, therefore, do not persist in the environment. Their effects are thus limited to the areas of application and are of relatively short dura tion. No undesirable long-term side effects are known to be caused by use of these biodegradable materials. Residues of some persistent pesticides, mainly the chlo rinated hydrocarbon insecticides, are very widespread in the environment. The most widespread of these com- Mining and processing wastes Mining and processing wastes are accumulating steadily. Often they represent a loss of resources and create esthetic and other problems. Minerals are being recovered where it is economic to do so, and some mining and processing wastes can be used as aggregate or for other structural pur poses. Recommendation S8: Research and development on proc esses for recovering various minerals from mining and processing wastes should be maintained at an adequate 68 C&EN SEPT. 8, 1969 SW 587998 STLCOPCB4093334 pounds is DDT. In addition, arsenic and some herbicides Minimizing contamination of the have been found to persist in some soils. environment with pesticides Available data show that most crops grown on pesticide- contaminated soils absorb only very small amounts of the Optimum methods of pest control will involve careful soil contaminant. In most cases the residues resulting from integration of chemical, biological, and cultural techniques. soil contamination are far below the tolerances established Such things as better application methods, improved formu for human food and, therefore, are below the concentra lations, effects of pesticides on insect parasites and preda tions which would be harmful to humans. Occasionally, tors, studies of population dynamics, and eradication of illegal, residues may occur if the pesticide with which the soil is contaminated is not registered for use on the crop pests will all help to decrease contamination of the en vironment with pesticides. Only in this way can the ob being grown. jective of economic control of pests on crops and animals Available evidence indicates that residues present in soils in most cases are not harmful either to the crop or to the be obtained with minimal environmental and ecological impact. soil microflora. In the U.S., most surface waters and their attendant sediments contain chlorinated hydrocarbon insecticides, particularly DDT and its degradation products, as well as Recommendation P4: An extensive educational program at all government levels is required to teach dll pesticide users the optimum methods of pest control. Recommendation P5: Research on biological and cultural some herbicides such as 2,4-D. The concentrations in methods of pest control should be continued. water itself are in the range of parts per billion or less. Recommendation P6: Persistent pesticides should only be Little is known about pesticide residues in air outside used in minimal amounts and under conditions where they the immediate vicinity of application. have been shown not to cause widespread contamination of Recommendation PI: Pesticide monitoring programs on all phases of the environment should be continued. In the the environment. Where possible, highly persistent ma terials should be replaced by rapidly degradable materials. case of air (and wildlife) the present programs should be extended. . Recommendation P2: For purposes of chemical analysis, Pesticides and wildlife research should be pursued on the development of more adequate methods for the separation of minute amounts of pesticides from water and air. Recommendation P3: Research should be expanded on the toxicity of pesticides when they are inhaled as opposed to dermal exposure or oral intake. Wildlife species in most parts of the U.S. carry ap preciable loads of chlorinated hydrocarbon pesticides. The principal hazard of persistent pesticides in the environ ment is their concentration in the food chain with con sequent harmful effects on fish and wildlife. Residues have accumulated in the food chain to a marked degree in a number of well-documented cases. These have caused death or debility of some nontarget species and have, in some cases, depressed reproduction. However, when one considers the widespread use of pesticides dining the past 15 to 20 years, the problems of this sort that have been en countered have been relatively few. Recommendation P7: More research should be conducted on the relationship between environmental pesticide con <I taminants and wildlife. This research, though based on chemistry and biology, should be done in an ecological context. Pesticides and human health Humans in the U.S. and elsewhere carry a body burden of 10 to 20 ppm of chlorinated hydrocarbon pesticides and their conversion products. By far the .greatest part of this residue is DDT and its degradation products. There is no evidence that long-term, low-level exposure to residues of pesticides such as occurs in the diet or environ ment in the U.S: has any undesirable effect on human health. 5 Recommendation P8: Additional\research is required on the impact of long-term, low-level exposure to pesticides on humans and other forms of life. In this connection, study is also required of the dose-response relationship of pesti cide chemicals suspected of being carcinogens. DSW 587999 :PT. 8, 1969 C&EN 69 STLCOPCB4093335 -- Bill HHI MB ______ How to make strong acids turn this thick. How? With General Mills Biopolymer. XB-23, a xanthan -gum. It can thicken and maintain the viscosity of strong acid sols-- including HCI, HF and H3P04 -- for months without degradation. This property sug gests numerous applications, including in dustrial acid cleaners and glass etchants. With XB-23 you can also thicken,, emulsify or suspend solids in a whole host of aqueous systems. Sols of XB-23 are pseu doplastic. 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