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Everyone Wants to Be Below Average -- in Cancer Rates
By Gilbert Ross, M.D.
A report today from northeastern Pennsylvania describes a fruitless search for the environmental "cause" of an increased rate of a blood disease called polycythemia vera (known among medical folk as P Vera -- here I'll use PCV). While not in fact a cancer, it often deteriorates into some form of leukemia, or it can lead to other blood disorders of high mortality. The federal epidemiologists found no specific explanation for the apparent increased incidence of PCV.
The residents of three Pennsylvania counties were led to believe that the occurrence of new PCV cases was both significantly increased and somehow related to a nearby toxic dump site -- which had been closed since 1979 and "cleaned up" via the Superfund law shortly thereafter. The preliminary figures were that the tri-county region had ninety-seven PCV cases over five years, when only twenty-five would be expected for a population that size.
However, when the federal investigators tried to investigate -- to find if there was some link, factor, or cause to tie all the PCV patients together -- they were only able to track down thirty-eight sufferers. One of the investigators said, "We did not find any environmental links to the PCV cases." However, a local internist, who is convinced that there is such a causative link, was not yielding any ground to the scientists: "This is an outrage," fumed Dr. Peter Baddick. "You downplayed it," he asserted, implying a conspiracy reaching (I suppose) into the highest levels of government, aimed at suppressing all such toxic-waste-caused cancer clusters.
Well, the numbers here don't rise to the level of a cause-and-effect issue anyway. Whether there are twenty-five or ninety-seven PCV cases, the risk of some factor in the environment causing this disease remains dubious at best. There is some expected variation in the rate of cancer across regions, just as with any other disease. Some areas are hit harder, some less so -- by chance. One-half of all counties will have a higher-than-average rate of whatever is being studied, while one-half will have a lower rate: basic math.
This investigation is consistent with cases described in our publication Cancer Clusters: Findings vs. Feelings, in which we discuss the various alleged cancer clusters and "cancer alleys" that have been trumpeted on the news over the past several decades. In summary: there isn't any such thing, outside of clusters caused by a few well-known cancer-inducing chemicals, almost always in super-high-dose occupational settings.
On another -- and even more disturbing note -- the government epidemiologist in charge, in trying to calm down the upset locals, said: "In addition to chemical and radiation exposure, well-documented initiators for cancer include stress, poor nutrition, and post-viral syndromes." Unfortunately, he is simply wrong about these: none of these factors are known (much less "well-documented") to "initiate" cancer. Obesity can increase risk of certain cancers, and some viruses can cause cancer (HPV, hepatitis B, HIV), but no "post-viral syndromes" can. It's bad enough when the local population gets caught up in a hypothetical cancer scare, but to have the "experts" start spouting nonsense as well is not to be tolerated.
Gilbert Ross, M.D., Executive and Medical Director of the American Council on Science and Health (ACSH.org, HealthFactsAndFears.com). See also: ACSH's full report on Cancer Clusters. 
LGK (October 26, 2007)
Dr. Ross wrote: "One-half of all counties will have a higher-than-average rate of whatever is being studied, while one-half will have a lower rate: basic math." This reminds me of two other shocking statistics: (1) Half the people in the U.S. have a below-average I.Q. (2) 40% of all worker sick days occur on a Monday or Friday. If someone asserts that the second statistic above implies that a lot of people who call in sick on a Monday or Friday are lying, then the first statistic probably applies to the one making that assertion.
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