DDT And Chlordane Killed By Politics, Not Science

Numerous tests were made on animals, mostly mice that were bred to be supersensitive to chemical stress. The mice were given massive doses of DDT long periods of time. Tumors did develop, but they did not metastasize into cancer cells. Many of the mice that were not fed DDT also developed tumors.

This didn’t matter to the Environmental Protection Agency. EPA regulations consider a benign tumor to be a cancer that justifies cancellation of registration. It should be noted that according to EPA regulations, a single positive test by one researcher takes precedence over the negative test results of 100 researchers.

LOW VS. GROSS DOSE. One of the Myth Conceptions that plagues the mindset of the general public, as well as various regulatory communities, is that a low dose of a toxicant is just as bad as a gross dose that can cause a tumor. If this were true, according to Dr. Bruce Ames from the University of California-Berkeley, we should not eat carrots, celery, parsley, mushrooms, cabbage, Brussels sprouts, mustard, orange and grapefruit juices, pepper, cauliflower, broccoli, raspberry and pineapple. All these foods contain natural toxicants that cause cancer in rats or mice when they are tested at the same gross levels that are used to test pesticides. Ames further claims that the natural level of toxicants in these foods is far higher than the trace residues on treated foods.

The Myth Conception of the carcinogenicity of DDT has a corollary with chlordane. According to the World Health Organization (WHO), when chlordane is used at label rates, there is no valid scientific test that shows carcinogenicity in humans. In 1984, a working group of the International Agency for Research on Cancer (IARC) reviewed existing data on chlordane and concluded that the evidence of carcinogenicity to experimental animals was indeed limited.

CHLORDANE’S EFFECT ON HUMANS. Many studies were made of chlordane’s effect on humans. The WHO reports about a study in 1981 in which mortality of 782 workers who manufactured chlordane and heptachlor for up to 20 years showed no increase in cancer in comparison to normal death figures. In another study by Wang and MacMahon in1980, all cancer deaths were lower than expected. In a follow-up study in 1982, the two Harvard researchers looked again at the mortality rates of termite control technicians and found there was no significant increase of cancer cases.

As secretary of the Western Pennsylvania Pest Control Association and as a formulator, I was concerned about the safety to PCOs. A Pittsburgh physician, Dr. Cyril Wecht consented to give annual physicals to employees of WPPCA members. In those days, the service technicians used chlordane carelessly. They had it on their hands, clothes, and breathed it in crawlspaces. Dr. Wecht found no effect on the liver or other vital organs, after several years of examinations.

MORE EXPENSIVE, LESS EFFECTIVE. There is much ado about the misapplication of termiticides. The regulators’ preoccupation with spacing of holes has little relationship with the concentration of toxicant in each cubic inch of soil. Backfills are usually a hodgepodge of building debris, hunks of clay and roots from dead foundation plantings. The most conscientious technician who carefully measures the concentrate and calibrates the flow of solution cannot be sure that every cubic inch of soil barrier is properly treated. Termites have nothing else to do but to look for that window of opportunity, an untreated pocket of soil.

In the Mallis Handbook of Pest Control, 8th Edition, Dr. Michael Potter claims that liquid dilutions tend to disperse randomly over the subslab fill, resulting in inconsistent coverage, and diversion from target areas.

If government tests of termiticide efficacy were made using the same label procedures mandated for PCOs, we would have no registered termiticides. As tested, the label should call for removal of the backfill to be treated, then mixing it with the termiticide solution in a cement mixer and finally replacing the mixture in the ditch. Fill material to be covered with a slab should also be treated the same way. Further, in testing for the presence of toxicant years later, multiple cores should be mixed and then tested.

The regulatory communities, who are looking for a fall guy to blame for the rash of termite control failures, ignore this double standard. Perhaps the officials should look in the mirror. When they killed relatively innocuous chlordane, they forced the public to pay three or more times the cost for termite control with no increase in safety and with limited residual value.

Harry Katz, a 50-year veteran of the pest control industry, is an independent consultant based in Deerfield Beach, Fla. To contact Katz, call 954/427-9716.