The DDT Ban: The Worst Of Two Evils

Most people believe DDT causes cancer. This Myth Conception, perpetuated by Rachel Carson in her epic work, Silent Spring, is likely to be a permanent legacy of the new generation of pest control operators and their clients.

There is only a handful of the passing generation of scientists who are aware that DDT has never been shown to be a carcinogen in valid, statistical, toxicological studies.

THE DDT SCARE. When Carson shocked the world with accounts of the gross misuse of the new miracle pesticide DDT, the Department of Health, Education and Welfare appointed a commission to determine if DDT was in fact a carcinogen. Five members of a subcommittee of the Mrak Commission (named after the congressman who oversaw it) were asked to determine if DDT was carcinogenic based on a National Cancer Institute (NCI) study. However, three of the committee members were associated with the NCI, whose study they were asked to review. Another member appointed to the Mrak Commission subcommittee was Carrol Weil, past president of the Society of Toxicology and a fellow at the prestigious Mellon Institute in Pittsburgh.

In a heated discussion that went on long after midnight, Weil insisted that the interpretation of the results of tests sponsored by the National Institute of Health were flawed. In these NCI tests, all statistical analyses of the results exaggerated the number of independent animals being tested. Weil’s opinion has since been validated with universal acceptance by the toxicology community, following publication of his paper in Food and Cosmetic Toxicology in 1970. In order to finally get a unanimous decision, Weil was asked to write a minority opinion to be published as an appendix to the Mrak commission report. This was followed in 1972 by extensive hearings, during which EPA administrative law judge Edmund Sweeney ruled there was no evidence that DDT caused cancer. William D. Ruckelshaus, head of the EPA, made a political decision, overruling his own counsel, and declared DDT a carcinogen. After DDT was banned for use in the U.S., other countries banned it as well. This turned out to be a death sentence for many millions of humans in underdeveloped countries. In 1945, 2.8 million people in Ceylon had malaria. After DDT was used, the figure was reduced to only 110 cases in 1961. After DDT was cancelled, 2.5 million were again infected with malaria. Harold Varmus of the NIH recalls, “when I was working in India in 1966, I saw almost no malaria, but when I returned in 1988, there was a raging epidemic.”

MALARIA ON THE RISE. In an article in Atlantic Monthly in August 1997, Ellen Ruppel Shell claims the incidence of malaria has quadrupled in the past five years. The World Health Organization now estimates that malaria kills as many as 2.7 million people annually (roughly twice as many as AIDS). She writes that resistance to drugs is partly to blame. “Nearly 40 percent of the world’s population lives in regions where malaria is endemic,” Shell wrote, “and millions more live in areas that are encountering the disease for the first time in decades.”

The Centers for Disease Control estimates that the actual incidence of malaria in the United States is actually twice the 1,200 cases reported. States most affected are California, Texas, Michigan, Florida, New Jersey and New York. Harvard’s Dyann Wirth warns that Americans must stop thinking of malaria only as a third-world plague. Increased world travel and excessive rainfall in some areas have created conditions conducive to the rapid spread of malaria in the U.S. In The Mallis’ Handbook of Pest Control, Jeff O’Neill tells us that one mosquito can, after five generations of ideal conditions, generate 20 million offspring. It is no wonder the CDC is concerned about the spread of malaria here.

Much of the published data on the cancer-related effects of DDT was based on evidence developed before it was learned that DDT and PCB (polychlorinated biphenyl) had similar “fingerprints” on the gas chromatograph. PCB had been widely used as an emulsion coating for carbonless paper. After being used and burned as waste, PCB volatilized and condensed into dust particles. Eventually falling into Arctic waters, it ended up in the fat of seals and other marine animals. No one will know how much of the DDT was really PCB, but the decision based on this nebulous finding in marine animals stands.

Much is made of eggshells being thinned by DDT. Bird eggs stored in museums for over a century were found to have abnormally thin shells. Farmers sometimes find their chickens producing thin-shelled eggs because of a calcium deficiency. It is ironic that a ruling which outlaws any toxicant which might increase cancer in more than one person out of a million, after 70 years of exposure, is the same ruling that results in the death from malaria of millions of people in other lands.

Harry Katz is a contributing editor to PCT.