World Use of Economic Poisons - Advances in Chemistry (ACS

This paper points out a few simple but fundamental reasons why expansion of the world use of economic poisons is being seriously retarded. These remar...
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World Use of Economic Poisons STEPHEN S. EASTER

Downloaded by UNIV OF MICHIGAN ANN ARBOR on May 12, 2018 | https://pubs.acs.org Publication Date: January 1, 1950 | doi: 10.1021/ba-1950-0001.ch002

Food and Agriculture Organization of the United Nations, Washington, D. C.

This paper points out a few simple but fundamental reasons why expansion of the world use of economic poisons is being seriously retarded. These remarks are based on personal observations in twenty different countries of North America, South America, Europe, and Africa, and on contacts with technical men in as many more countries.

It is obvious that the world use of economic poisons can be greatly expanded; no a t tempt will be made to say how much. The use of pesticides is frequently associated with the spectacular nature of a pest or the urgency of meeting its attacks. Grasshopper or locust campaigns are, generally speaking, easy to sell to the administrative powers because these periodic pests destroy all the crops attacked. Quick action must be taken to save the crops. O n the other hand, continual annual crop losses from other pests may, over a period of years, equal or exceed those caused b y locusts, but these losses are accepted as a matter of course because only a part of the crop is lost each year. I n 1945 three Central American countries imported 38,500,000 pounds of copper sulfate-and only 75,000 pounds of all other pesticides. T h e copper sulfate was used almost exclusively i n the preparation of Bordeaux mixture for the control of the sigatoka disease of bananas. Without this control measure, the bananas could not have been grown profitably. During 1948 i n the same countries the imports of certain other pesticides increased greatly because of the need for locust control. I t is to be expected that, after the locust outbreak subsides or is controlled, these imports will drop again. The use of economic poisons has expanded i n the field of public health since their indispensability has been shown i n the control of insect-borne diseases. T h e organic insecticides, especially D D T , are now being used extensively i n the control of malaria, yellow fever, dysentery, and other diseases. Their use i n this field will certainly expand for years to come. Lea Hitchner of the National Agricultural Chemicals Association estimates an annual use of $200,000,000 i n pesticides for the United States. I n spite of the fact that the United States has been using more pesticides than any other country, the amount used has increased steadily. There is still a likelihood of expansion here. The introduction of the Colorado potato beetle into various European countries has created a potential market for insecticides. Its recent spread into Germany and Poland has been followed b y a marked increase i n the use of various kinds. The past history of this insect indicates that steadily increasing amounts of insecticides will be needed annually i n order to control i t . More examples could be given to show potentially greater use of economic poisons, but all would show the same trend. The manner i n which the world chemical industry quickly produced vast tonnages of D D T during the war was amazing. E v e n more so was the efficiency achieved i n production, so that entomologists had an insecticide available at a price which permitted its 5

AGRICULTURAL CONTROL CHEMICALS Advances in Chemistry; American Chemical Society: Washington, DC, 1950.

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use. The chemical industry is still far ahead of the entomologists. New insecticides are being produced more rapidly than the entomologists can test them. The same can be said for other pesticides used to combat plant pathogens or weeds. The new chemicals must be properly tested and evaluated before being released as pesticides. M u c h cooperative work is needed. After all, D D T was only a chemical entity for over 60 years before its insecticidal properties were discovered. Today, i n most of the world, application of the presently known good pesticides is needed far more than discovery of other new ones.

Downloaded by UNIV OF MICHIGAN ANN ARBOR on May 12, 2018 | https://pubs.acs.org Publication Date: January 1, 1950 | doi: 10.1021/ba-1950-0001.ch002

Work of the FAO These observations relating to the use of economic poisons have been made through the work of the Food and Agriculture Organization of the United Nations. F A O is an autonomous body of 58 nations concerned with all phases of food, agriculture, forestry, and fisheries throughout the world. It was conceived because, i n peace or war, the majority of the world's peoples are not amply fed and on the premise that food is basic to human well-being and world peace. F A O is not a relief agency. It does not purchase or distribute food products, although it is much concerned with food deficits and food surpluses. Neither is it a research agency, though it does try to enlist the interest of scientists i n its fields and coordinate their efforts in the solution of pressing problems. Finally, of course, it is not a political organization, but operates as an international extension agency on a strictly impartial basis. A t the present time many nations are sharing their food with other less fortunate n a tions—less fortunate because of the devastation of war, drought, poor crops, or other reasons. There seems to be no other immediate solution. B y sharing the scientific knowledge now available for increasing food production, the devastated and underdeveloped countries can be enabled to increase their own food production. It is true that some nations will probably always be partially dependent on imports of food, but i m proved methods of production, processing, and storing will reduce the degree of dependency. The dissemination of technical information is a major responsibility of F A O . It may be done i n various ways, according to the problem. F A O is primarily concerned with problems relating to food. Entomology is so closely associated with the production and saving of food that this phase of work is obviously i m portant to the Agriculture Division of F A O . The field of agricultural entomology i n the world is so broad that an extremely large staff would be required if F A O attempted to cover the entire field. The entomological staff is small and its coverage is limited. However, it is not the purpose of the staff to conduct research or to participate i n action programs. A few specific problems of world-wide interest have been selected for study. These i n clude the pests of stored food, the Colorado potato beetle, the Moroccan locust, and the field insects of China. I n addition, advice may be given on control of introduced insects. The technical knowledge of America and western Europe is drawn upon freely. The task of F A O is to assist the member nations, especially those least developed; consequently, this section becomes a kind of international entomological extension service.

Stored Food Attention has been focused by F A O on the tremendous losses in stored food over the world caused by insects, rodents, and fungi. International meetings have been held on the subject i n Washington, D . C , London, England, Florence, Italy, and Cali, Colombia, where technicians from many countries have gathered to study the problem and exchange information on means of solving it. I n addition, field trips have been made to different countries to study grain storage. As a result of these meetings and field trips some progress has been attained. The potential use of economic poisons i n this specialized field may be stated as follows : The use of fumigants will increase, but no faster than the construction of improved storage facilities which will permit the efficient use of fumigants. Residual insecticides will i n crease i n use for many years, but the total tonnage will not be high. I n a few countries, AGRICULTURAL CONTROL CHEMICALS Advances in Chemistry; American Chemical Society: Washington, DC, 1950.

EASTER—WORLD USE OF ECONOMIC POISONS

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insecticides are being added directly to grains to ensure protection against insect attack. A trend i n this direction could result i n a great increase i n the use of economic poisons. Two factors are delaying i t at this time—cost and hazard to the consumers. The millers resist any addition of foreign material to the grain because they have to take i t out again. I n the small subsistence-producing nations this method appears to hold much promise. A general use of rodenticides i n grain storage plants would not require many tons of chemicals and would not be much of a factor i n expanding the world use of economic poisons. The heating of grain i n storage has been controlled by the use of certain chemicals added to the grain, but the cost is still too high for practical use. The fungi are controlled by drying and there is little likelihood of a market here for economic poisons for many years to come.

Costs Further remarks regarding costs of insecticides or inadequacy of equipment used are generally applicable to the whole field of pesticides and are not limited to their use in grain storage only. W h y is the world use of economic poisons being retarded? The price paid for the pesticide b y the ultimate consumer is frequently prohibitive i n importing countries. The quality of the pesticides obtained from the major producing countries is excellent, but this quality is of little value if the price prevents its use. A few examples may be quoted to demonstrate this point. In one European country where field insecticides are not generally used but are very promising, 5 0 % wettable D D T of American manufacture was purchased i n midyear 1948. The retailer was a large cooperative with presumably favorable prices to consumers, yet the price to the consumer i n that country, at the official rate of exchange, was roughly $1.50 per pound. A t the same time this identical material was selling f.a.s. New Y o r k at $0.23 per pound. It is granted that the price per pound must be higher to compensate for freight, handling, selling costs, etc., but there is no justification for an i n crease of 500%. The inevitable result is either the refusal of the imported material as an aid to agriculture or, i n case of emergencies, a trend toward establishment of small local manufacturing plants which are made secure i n their inefficiency by protective tariffs. The end result is the same to the consumer—prohibitive prices. The example given for Europe can be repeated for numerous other countries and on other economic poisons. The differential may be as great i n a few places. I t is not found on all poisons. The correction of this one factor lies mainly i n the sales organizations responsible for supplies to the foreign markets.

Equipment for Pesticide Application Pesticides and the equipment with which they are applied are so fundamentally associated that i t is astonishing to see how often these two items are separated. Pesticides are frequently sold i n a foreign area with complete disregard of the available means of application; yet the whole future market depends mainly upon the proper distribution of the materials. The want of suitable equipment can be a very serious factor i n retarding the use of economic poisons. There are many examples of equipment being sold i n areas for which i t is not suited. The unsuitability may be a lack of trained operators, a lack of basic knowledge of the equipment's possibilities, equipment inappropriate to the terrain, or, occasionally, equipment so highly specialized that i t cannot be adapted to the general use for which i t is needed. I n general, simple equipment can best be used to demonstrate the value of the use of pesticides. One specific piece of equipment, which had to be mounted on a vehicle, was extensively sold for locust control i n an underdeveloped country. The roads i n this area were not passable to trucks and the machine was mounted on a jeep. The machine was too heavy for a jeep, so the net result was a broken-down jeep and a piece of specialized equipment shaken to pieces b y travel over almost impassable terrain. A d d to this the complete lack AGRICULTURAL CONTROL CHEMICALS Advances in Chemistry; American Chemical Society: Washington, DC, 1950.

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of operators with mechanical training and a lack of appreciation for dosage per acre, and the final result is either of two things : When the equipment is working the amount of i n secticide applied per acre greatly exceeds the needs, and when the equipment is not working a large crew of workers and other vehicles are inactive for long periods. Simple oneman dusters would have done a far better job at a greatly reduced cost. The value of the insecticide also would have been better demonstrated. In some areas where grapes are raised on a large scale the use of small one-man sprayers is well established for the control of disease. In Southern Europe, for instance, these sprayers have been designed for the use of i n expensive fungicides, typified by home-mixed Bordeaux mixture. Neither the nozzles nor the guns are suitable for the use of high-priced organic insecticides or fungicides. I n order to get the proper application of the new pesticides, suitable nozzles and guns must be used. A t present the flow rates are too high and the spray patterns are far too coarse to give desirable coverage with such insecticides as wettable D D T or benzene hexachloride. The guns are frequently a plain quarter-turn valve, rather than a simple gun with a mechanism for permitting the quick release and cut-off of flow. The only justification offered for a quarter-turn valve i n place of a gun is the very minor saving i n the original cost. This is not good economics, because the savings i n the original investment are quickly lost by the wasted pesticides of a few days' field operation. Theoretically, when spraying fruit trees the operator always turns off his quarter-turn valve when walking from tree to tree. I n practice, however, this is frequently not done because both the operator's hands are occupied otherwise. It becomes only too obvious that many of the designing engineers have not used, under practical conditions, the equipment they have designed. Equipment of this type is being sent into South America. There are many other small factors that affect the operation of pesticide-applying equipment. There is, unfortunately, a tendency on the part of many people to forget the basic reason for spraying—the control of plant pests. The chemical industry should keep i n mind that pesticides, no matter how excellent their quality, or how abundant their quantity, are useless in a warehouse and are of value only after they are applied i n the field. The means of application is therefore a very fundamental consideration i n the expansion of economic poisons. I n recent years there has been a great increase i n the degree of cooperation between the engineers designing equipment and the scientists who are concerned with application. The lack of technicians i n underdeveloped countries is a serious handicap i n the i m mediate expansion of the use of economic poisons. The salesmen representing the producers commonly tend to exaggerate the merits of their products when selling i n the foreign market. Claims are made without scientific investigation to substantiate them. Such practices are particularly harmful because of the lack of technicians. Help is needed from technicians who can work on the problems i n other countries, not at home. There is, for example, a very large potential market for an insecticide that will control leaf-cutting ants. These insects are one of the major entomological problems from Mexico to the Argentine. A simple cheap method of control is needed. There are several promising leads, but almost nothing is being done to find such a method. The labels of pesticides going into foreign markets should receive careful attention to guard against misunderstanding the directions. There is likely to be a language difficulty, and even i n the foreign language the directions should be clear and concise. A n d the change to the metric system should not be overlooked. M u c h misunderstanding can be avoided by sending technical men to give first-hand information where export is desired. Some customer service in foreign markets by technicians would pay excellent dividends in the increased use of pesticides. The world use of economic poisons can be expanded. There are simple basic factors retarding this expansion: prohibitive consumer prices, lack of equipment with which to make proper field application, lack of skilled personnel in countries needing the benefits of economic poisons, exaggerated claims of nontechnical salesmen, and difficulties involved i n labeling the export products.

AGRICULTURAL CONTROL CHEMICALS Advances in Chemistry; American Chemical Society: Washington, DC, 1950.