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In the war against his insect enemies, man has reached the point where his poisons not only kill birds and animals but threaten the human population as well

In the last three years the U.S. Department of Agriculture, warring against the fire ant, has sprayed more than 1,750,000 acres in the Southeast with chemical pesticides far more poisonous than DDT.

In the last few weeks the U.S. Fish and Wildlife Service has reported finding 59 species of animals, including game birds, dead on the ground in sprayed areas. These animals all contained residues of dieldrin or heptachlor, the two chemicals used.

In the same period the Food and Drug Administration declared a zero tolerance for heptachlor in foodstuffs for human consumption.

Thus man's chemical warfare against his insect enemies has at last reached the point where it threatens the well-being of man himself. The multimillion-dollar campaign waged by the Department of Agriculture against the imported fire ant has brought the whole question of the mass use of pesticides into violent focus. Yet the spray program for fire-ant control is only one of several in which scientific investigators have found alarming results. Here are some of the others:

•Heavy losses of game and nongame fish were discovered four months after DDT was sprayed on a large tract of forest in the watershed of Montana's Yellowstone River. On less than 300 yards of stream 600 dead or dying whitefish, brown trout and suckers were counted, and Professor Richard J. Graham found fish dying 90 miles below the treated watershed. The fish were found to contain DDT.

•On the east coast of Florida 2,000 acres of tidal marsh, traversed by 354,000 linear feet of ditches, were sprayed by airplane with dieldrin to control sand flies. The fish kill was nearly complete, estimates running to between 20 and 30 tons, or about 1,750,000 fish, representing some 30 species.

•Robins and other highly desirable birds were wiped out in a number of communities in the Midwest, where spraying with DDT has been conducted for control of the Dutch elm disease. On the campus of Michigan State University Dr. George J. Wallace found original nesting robins were killed and others moving in to replace them also fell prey to the poison.

•Damage to birds and mammals was reported by T. G. Scott, Y. L. Willis and J. A. Ellis from applications of dieldrin for control of Japanese beetles in Illinois.

•Research conducted by the U.S. Fish and Wildlife Service has shown that as little as½00,000 of an ounce of dieldrin per day in the food of pheasants resulted in eggs of low hatchability and chicks subject to abnormally high death rates.

•Some streams already have been polluted with pesticides, and DDT has been found at the mouths of even the largest rivers, including the Mississippi and the Columbia.

All the foregoing were the results of a program which, according to the Pesticide Committee of the International Association of Fish, Game and Conservation Commissioners, in 1958 accomplished the following: "Chemical controls were applied to more than 100 million acres of land in the United States, with additional millions more in Canada and Mexico. Mixed with dusts, oils, water and other solvents, emulsifiers and carriers, the volume totaled between 2 and 3 billion pounds and cost the consumer over $500 million. Currently, one sixth to one fifth of our croplands and millions of acres of forest and range lands are treated annually with pesticides in quantities of a few ounces to 25 or more pounds per acre." As for the future, the report added: "Entomologists expect a fourfold increase in the use of insecticides during the next 10 or 15 years."

On March 28 Justice William O. Douglas in effect proposed that the entire problem of mass spraying of toxic chemicals be reviewed by the Supreme Court of the United States. He stressed the importance of the issue in an indignant protest when the Supreme Court refused to consider the legality of a Department of Agriculture program to spray DDT from airplanes on more than 3 million acres of land in 10 states.

Justice Douglas' action climaxed a four-year battle by 13 residents of Long Island, N.Y., including Dr. Robert Cushman Murphy, the ornithologist, and Archibald B. Roosevelt, son of President Theodore Roosevelt, to curb pesticide spraying in their area. They had sought an injunction in 1956 against the Department of Agriculture's spraying of DDT to eradicate the gypsy moth, on the grounds that it would poison vegetables, animals and human beings. While the case was moving through the courts the department moved through the air and the spraying was done. The Government then said it had no intention of repeating the spraying. The Second Circuit Court of Appeals held, therefore, that the question was moot, or a dead issue, and the Supreme Court refused to review this decision.


After discussing some of the testimony in the case, Justice Douglas wrote, "The public interest in this controversy is not confined to a community in New York. Respondents' spraying program is aimed at millions of acres of land throughout the eastern United States. Moreover, the use of DDT in residential areas and on dairy farms is thought by many to present a serious threat to human health, as evidenced by the record in this case as well as by alarms sounded by others on the problem. The need for adequate findings on the effect of DDT is of vital concern not only to wildlife conservationists and owners of domestic animals but to all who drink milk or eat food from sprayed gardens....

"I express no views on the merits of this particular controversy. Nor do I now take a position on the issue of mootness. But I do believe that the questions tendered are extremely significant and justify review by this court."

It is not only the scope of the spraying program but the changing nature of the compounds used that has led to such mounting concern. Since World War II, when DDT was put on the market, the deadliness of pesticides has increased markedly. Insects were found to develop immunity to DDT, and so the demand arose for stronger compounds with a wider killing effect. A long list of new organic pesticides was therefore developed, including the chlorinated hydrocarbons. Now more than 200 pesticides are sold in various formulas under thousands of trade names.

Dr. Clarence Cottam, director of the Welder Wildlife Foundation, Sinton, Texas (SI, Jan. 21, 1957), and former Assistant Director of the U.S. Fish and Wildlife Service, is one of the leaders in the campaign against the wholesale and indiscriminate spraying of these toxic materials.

"The magnitude of this problem is tremendous," Dr. Cottam says. "It suggests to me that ultimately legislative action by Congress may be necessary to give more effective protection to man and his resources against overzealous operators. Knowledge needs to be available concerning the probable or possible indirect, as well as the direct, effect of the projected operational program."

The new chlorinated hydrocarbons have many curious properties. As a group they are highly toxic, but some are more poisonous than others and their effects are different upon different organisms. Upon being ingested some of them change form. In the body tissues of animals, for example, heptachlor metabolizes to heptachlor epoxide, which has proved to be more poisonous than the original compound. These chlorinated pesticides are also surprisingly stable and remain in the environment long after they have been deposited. Dieldrin and heptachlor remain lethal to invading fire ants from three to five years and possibly longer.

In the case of the imported-fire-ant program, appropriations for "eradication" were voted by Congress, and it then became the obligation of the Department of Agriculture to carry out the program through its Pest Control Division. Officials administering the program have held that if they were permitted to carry on an all-out campaign the ant could be eliminated and any areas suffering damage to wildlife would be repopulated naturally. It is a matter of historic irony, however, that the entire furor over the fire ant has been concerned with an insect which, on further investigation, has turned out to be something less of a menace than it was originally made out to be.

Not so the poisons. One of the warnings sent out to local residents in advance of the spraying, for instance, says: "Cover gardens and wash vegetables before eating them; cover small fish ponds; take fish out of pools and wash pools before replacing the fish; don't put laundry out; keep milk cows off treated pastures for 30 days, and beef cattle 15 days; cover beehives or move them away; keep children off ground for a few days; don't let pets or poultry drink from puddles."

Gradually the imported fire ant seemed to lose some of its viciousness. There were denials that it ate crops. Health officials said it was not a menace to human beings. Dr. Kirby Hays, an entomologist who was sent to Argentina by the state of Alabama to study the ant on its home grounds, reported that the people of Argentina considered the insect beneficial because it attacked a number of destructive insects. Last week the National Wildlife Federation asked Congress outright to stop or drastically modify the fire-ant control programs, pointing out that "the fire ant is a nuisance, but nothing more." The value of its control, said Louis C. Clapper, acting conservation director, "is more than offset by long-term damage to wildlife, fish, domestic livestock and poultry and beneficial soil organisms." The department itself cut down the recommended dosage of two pounds per acre to a quarter pound per acre, with a second spraying of the same amount three to six months later.

Meanwhile, biologists were following the trail of the sprayers. At the Twenty-fifth North American Wildlife and Natural Resources Conference held last month in Dallas, Dr. James B. DeWitt, of the U.S. Fish and Wildlife Service, delineated the results of research he and his coworkers had conducted at the Patuxent Wildlife Research Center near Laurel, Md.

It was Dr. DeWitt who listed the 59 species of poisoned animals that had been obtained from areas sprayed for fire ants. The list included songbirds, quail, rails, ducks, rats, mice, raccoons, foxes, snakes, frogs and fish. Dr. DeWitt also reported that earthworms, an important food of some birds, taken as much as 12 months after treatment of an area with the pesticide, contained from one to 10 parts per million of heptachlor epoxide.

The cost of the fire-ant program has been great. During three years Congress has appropriated $7,200,000 for the spraying. With additional funds appropriated by state legislatures, the total cost has risen to between $10 and $12 million. Meanwhile, both the spraying and the controversy continue, although some states have reduced or withdrawn financial support of the program.

Most of those who are in violent opposition to such massive spray programs agree that pesticides have become an unavoidable part of the economy. However, they do make strong pleas for a revised approach to the problem. Instead of stronger poisons with wide killing ranges they urge less toxic but more specific chemicals and the use of spot methods of application rather than the wholesale dosing of big areas from airplanes. Above all, they plead for greater cooperation between biologists and those exercising control programs.

A bill to that effect, called the Chemical Pesticides Coordination Act, was introduced in Congress on March 31 by Representative Leonard G. Wolf of Iowa. This bill would require advance study of the effects upon fish and wildlife before any federal program using chemical pesticides could be undertaken. It would require not only preliminary study by the U.S. Fish and Wildlife Service but also by the game and fish department of the state affected. The Fish and Wildlife Service would be directed to cooperate in developing methods that would achieve the necessary controls while minimizing damages to wildlife resources.

Many of those taking an active part in the controversy feel that this is a good step, but that a much broader appraisal of the mass use of chemical poisons is needed. Dr. Wallace of Michigan State, viewing the drastic toll of robins and other birds after his investigations, expressed a view of blackest pessimism and indictment: "The current widespread and ever-expanding pesticide program poses the greatest threat that animal life in North America has ever faced—worse than deforestation, worse than market hunting and illegal shooting, worse than drainage, drought or oil pollution and possibly worse than all of these decimating factors combined." Dr. Cottam, more temperate but no less positive, argued for "selective and specific pesticides which we can use to control pests without significant detrimental effects to other public values or to other members of the biota which are of high economic, social or recreational importance. It has been done before." Dr. Cottam concluded, "The possibilities are there, and the promised rewards are worthy of our best efforts."