This past summer Daniel John Sobieski wrote a letter about one of my columns. I felt honored. For those of us who regularly read the letters to the editor in Chicago newspapers, Sobieski is a household name. If memory serves, he has been a regular contributor for at least 30 years.
His name is distinguished. John Sobieski was once king of Poland. He led the army that lifted the Turkish siege of Vienna in 1683, ending the last great Muslim thrust into Europe. Chicago’s Sobieski writes in support of ideas that would have been to the right of center even in the king’s time.
The column I wrote was about some proposed changes in the Illinois endangered- and threatened-species lists. I pointed out that the status of bald eagles–among other species–had been improving consistently since the use of DDT was banned in 1972. It was this remark that upset Sobieski and led him to write the following letter:
Jerry Sullivan writes about “the beneficial effects of the ban on DDT,” a ban largely brought about by Rachel Carson’s book Silent Spring. Carson’s book was in fact a fraud that contributed to the suffering and death of millions.
Carson had claimed that due to DDT the American robin was on the verge of extinction in 1962, but bird expert Roger Tory Peterson stated that it was the most common bird on the American continent. Aubudon bird counts per observer increased for the majority of species between 1941 and 1960. The red-winged blackbird, which lives in marshes that were sprayed with DDT to kill insects, underwent a population explosion from 1.4 million in 1941 to 20 million in 1960.
In 1946 the country of Ceylon, now Sri Lanka, suffered some 2.5 million cases of malaria with annual deaths at 12,500. After the country introduced DDT spraying programs, the number of cases fell to 17 a year by 1963, with deaths averaging less than one a year from 1958 to 1967. But after environmental hysteria stopped the spraying, the number of malaria cases quickly grew back to half a million.
Gordon Harrison, who was director of the Ford Foundation’s environmental program, has noted, “India had brought the number of malaria cases down from an estimated 75 million in 1951 to about 50,000 in 1961.” Then, as DDT use declined, “Endemic malaria returned to India like the turnaround of a tide. By 1977, the number of cases reached at least 30 million and perhaps 50 million.”
Does this suggest that DDT was a threat or a benefit to civilization? Indeed, according to Dr. Elizabeth Whelan, president of the American Council on Science and Health, during its less than 30 years of use (1944-’72), DDT prevented more human death and disease than any other man-made chemical in all of recorded history. Today there are 2.1 billion people at risk for malaria round the world, with an estimated 2.7 million people who die from malaria annually. There once was an effective way of fighting malaria. It was called DDT.
During 1972, the Environmental Protection Agency held official hearings on the scientific evidence concerning DDT. After seven months and 9,000 pages of testimony, EPA hearing examiner Edmond Sweeney decided on the basis of the evidence that DDT should not be banned.
In his final decision on April 26, 1972, Mr. Sweeney stated, “DDT is not a carcinogenic, mutagenic, or teratogenic hazard to man. The uses of DDT under the regulations involved here do not have a deleterious effect on freshwater fish, estuarine organisms, wild birds or other wildlife….The evidence in this proceeding supports the conclusion there is a present need for the essential uses of DDT.”
But six weeks later EPA administrator William Ruckelshaus, who did not attend any of the hearings, overruled the decision and banned DDT based on the political propaganda of environmental groups that had used the DDT scare to gain funds and recruit members. For those who died since and are dying still, it has indeed been a silent spring.
I tend to react negatively to people who call Rachel Carson a fraud. Sobieski’s ideas are easily dismissed, but since claims like his often creep into the mainstream media, I thought I might give his letter an extended response. I’ll start with red-winged blackbirds, which have enjoyed a vast increase in number because they have invaded habitats they did not previously occupy. According to a study by Richard and Jean Graber published by the Illinois Natural History Survey, 60 percent of Illinois’ redwings nested in marshes in 1909. By 1958, 97 percent of the population was nesting at woodland edges, roadsides, hay fields, and other upland sites. And the rise in bird counts per observer is an artifact–a product of better binoculars, better field guides, and better birders.
I thought it would also be easy to refute Sobieski’s claim that Carson had considered the robin a species being pushed toward extinction by DDT and other pesticides. The robin is probably the most abundant bird in North America. Robins nest everywhere from Oaxaca to the shores of the Arctic Ocean in habitats ranging from city neighborhoods to wilderness woodlands. Rachel Carson was a trained scientist and an active birder. Surely she wouldn’t make such a wild assertion.
I started scanning her book to see if I could find anything to support Sobieski’s charge. This book is hard to scan. It is too passionate, too well argued, too well-grounded in fact. It demands careful reading. I can thank Sobieski for sending me back to a book I last read more than 30 years ago. It is certainly one of the great works in the history of polemical literature. It did change our perceptions. Reading it took me back to a time when DDT mixed with fuel oil could be sprayed from airplanes onto suburban neighborhoods in a futile attempt to control Dutch elm disease or Japanese beetles, to a time when millions of acres of forest could be subjected to aerial spraying for spruce budworms or gypsy moths.
Robins were dying then, dying with the tremors and convulsions of insecticide poisoning. On the campus of Michigan State–where DDT was sprayed on elm trees at the rate of five pounds per tree–biology professor George Wallace and a graduate student named John Mehner found that it took about a week to kill each wave of spring migrants. And those that survived could not reproduce. Within five years of the beginning of spraying, robin numbers were down 90 percent, and not a single fledgling could be found on the 185-acre campus. At the University of Wisconsin, Joseph Hickey was discovering more than 85 percent mortality in robins in sprayed areas. Near Sheldon, Illinois, where spraying was done to control Japanese beetles, an Illinois Natural History scientist described robins as “almost annihilated.” Roy Barker of the Illinois Natural History Survey found high levels of DDT in the digestive tracts, nerves, blood vessels, and body walls of earthworms. The worms were biomagnifiers, delivering DDT to the robins that ate them. Barker calculated that 11 worms would make a lethal dose.
Altogether, about 90 species of songbirds showed heavy mortality in sprayed areas, with ground feeders–such as robins–getting hit the hardest. In Mississippi, Louisiana, and Alabama massive spraying of heptachlor in a futile attempt to control fire ants was added to the heavy agricultural use of pesticides; “Field Notes,” a quarterly report on birds jointly published by the U.S. Fish and Wildlife Service and the National Audubon Society, noted the existence of “blank spots weirdly empty of virtually all bird life.”
And none of this stuff worked. Gypsy moths continued to spread. Despite six years of heavy annual spraying on the University of Illinois campus in Urbana, Dutch elm disease claimed nearly half the elm trees. Of course in the pre-Silent Spring years the failure of a program that dumped five pounds of DDT on every tree was taken as a justification for dumping ten pounds.
Many of the catastrophes Rachel Carson predicted did not happen–largely because her book helped us change course. Silent Spring made it possible for Sobieski to ridicule her fears about the future of robins.
Sobieski’s claims about human health are as shaky as his thoughts on robins. Let’s get the chronology straight. DDT was banned in the United States in 1972. The ban did not extend beyond our borders, and DDT continued to be manufactured here for sale abroad. In 1975 global consumption of the chemical was estimated at 150,000 metric tons–about double the amount the U.S. produced in 1960.
According to Sobieski, malaria cases reached their low point in India in 1961–11 years before the U.S. ban. The low point in Sri Lanka was 1963, and things started back up after 1967. In other words, the rise in malaria cases preceded the ban on DDT by many years. In fact, according to a World Wildlife Fund report provided to me by Clare Hintz of Chicago’s Safer Pest Control Project, DDT is still produced in at least four countries, including India. The Indian government uses its homegrown DDT exclusively for malaria control. If malaria was killing more people in 1977 than in 1961, the reason was not a shortage of DDT.
May Berenbaum, a professor of entomology at the University of Illinois, explains in her book Bugs in the System what was actually going on: “In every insect population there is variability with respect to susceptibility to insecticides. When selection pressure from insecticides is intense, the population can rapidly shift from predominantly suspectible individuals to predominantly resistant individuals.”
The first report of insects showing resistance to DDT came in 1942, immediately after the first use of the chemical. Reports of immunity grew steadily. Carson reported on the first case of immunity in anopheles mosquitoes, the carriers of malaria, which occurred in Greece as early as 1949. By 1976, according to Berenbaum, more than 200 species showed such resistance.
The general conclusion about DDT–and other pesticides–is that the more you use them and the longer you use them, the less effective they become. Resistance to pesticides is the predictable outcome of heavy pesticide use. Meanwhile the harmful effects continue. Spider mites are now serious pests for soybeans and other crops as well as significant forest pests. Corn earworms do noticeable damage to corn crops. Both of these creatures did little damage before heavy pesticide use eliminated the natural controls that kept their numbers in check. And the ability of DDT to bioaccumulate–to increase in concentration by thousands of times as it moves through the food chain from mosquito larvae to tadpole to fish to bald eagle–continues to harm long-lived animals at the top of the food chain. The effects on human health would demand a whole column.
By the way, Rachel Carson did not oppose the use of pesticides under all circumstances. She writes approvingly of herbicide applications done by workers with backpack sprayers. The herbicide is tightly controlled, applied in small amounts, and touches only the target plants. And she notes the importance of natural controls and alternatives to pesticides. In fact, the contemporary idea of integrated pest management, which uses chemicals sparingly as part of a broad range of pest-control techniques, can claim her as a supporter.
The real mistake of believers in heavy pesticide use is a failure to understand nature. They look at a dynamic, highly interconnected, highly responsive system and see it as a static collection of isolated species as mindless as a windup toy. They seem to believe that if DDT works once it will work forever. If we want it to kill mosquitoes, it will kill mosquitoes and not bother anything else. And since nature is something out there that is not connected to us, we don’t need to worry about the possible effects on humans of continued heavy use of persistent, toxic, bioaccumulating chemicals. Beliefs like these led to the heavy use of DDT. The failure of this approach was as inevitable as the sunset. Rachel Carson just called our attention to the scope of the debacle.