Terence Hines - Pseudoscience and the Paranormal

Ironically, as is so often true in cases of national mass hysteria, the cure here was worse than the disease. In fact, there really wasn’t any disease to worry about in the first place. While, as noted, very high levels of exposure to asbestos in individuals working with it in their occupations can lead to lung cancer, the level of exposure in buildings that have been constructed with asbestos materials is trivial. Mossman et al. (1990) review the epidemiological studies on such exposure and conclude that the risk from such exposure is “minuscule” (p. 299). For example, playing football in high school carries a risk of death that is, minimally, 107 times greater than exposure to asbestos in school. The risk of dying from an accident at home while between one and fourteen years of age is 645 times greater. Finally, the risk of dying from lung cancer caused by the best-known cause of lung cancer, prolonged cigarette smoking, is almost 13,000 times greater than that from asbestos exposure. To make matters worse, the very removal of asbestos from buildings created a new group of at-risk workers—the abatement workers who had to actually remove the asbestos.

The asbestos panic shows several characteristics of the cases of national mass hysteria that followed it. A real disease (lung cancer) came to be linked—not through any scientific evaluation, but by a sort of “guilt by association” mechanism—with a fairly common and previously accepted environmental agent. Once this association was made, the media hyped the story, feeding the panic, much like throwing gasoline on a fire, while claiming to be trying to put it out. Unique to the asbestos case, an industry sprang up to remove the nonproblem material. As will be seen, this was generally not a possibility with several subsequent panics. Certainly not unique to the asbestos case, lawyers appeared and filed liability actions left and right. But here they were not as well organized as they would become in later cases. Of course, panics grow rapidly, while good science takes years to do. Thus, by the time it became clear from epidemiological studies that exposure to low levels of asbestos was basically harmless, billions of dollars had been wasted on abatement procedures, and who knows how many hours of research had been squandered that would have been much more productively used to examine more important medical questions.

The alleged health risks of microwave radiation formed the prelude to the next major incident of (in this case) international mass hysteria. The fear here was that the electromagnetic fields (EMFs) from power lines caused, among other things, cancer, especially in children who grew up near power lines. The fear about the dangers of microwaves first surfaced in the mid-1970s with the publication of two articles in the popular New Yorker magazine that were later published in book form (Brodeur 1977). According to Brodeur, exposure to microwaves produced numerous unpleasant health effects, up to and including cancer. During the mid- to late 1970s, microwave ovens were introduced and becoming popular, so there was fertile soil for the seeds of fear to fall on.

The most serious claim was, of course, that microwaves caused cancer. But, as Park (2000) has noted, there is no mechanism by which microwaves could cause cancer. When cancer is caused by some external agent (as opposed to cancer caused by genetic problems within the individual’s genome), the mechanism is the breaking of chemical bonds in the DNA. Microwave radiation simply doesn’t have enough energy to break these bonds. Park (2000) uses an excellent analogy to clarify this point: Imagine trying to throw stones across a river to break a target on the other side. If you’re not strong enough to get the stones across the river, it doesn’t matter how many you throw, the target will remain undamaged.

Throwing more stones in this analogy is equivalent to increasing the intensity of the microwaves. This does have a result—heat. That is why microwave ovens work. But by the time this increased heat had broken any DNA bonds, the target tissue would have been cooked and cancer would be the least of its worries. For a more technical discussion of this point, the reader should see Adir (1991). The anxiety over the would-be dangers of microwaves faded out over the next several years, probably, as Park cogently points out, because of the realization that microwave ovens were extremely handy things to have around the kitchen.

But if the microwave portion of the electromagnetic spectrum had ceased to inspire fear and dread, another portion was just becoming a target for even more panic. And once again, Paul Brodeur was in the lead. It was Brodeur who sounded the alarm, again in a series of articles in the New Yorker which were later published as a book (Brodeur 1989). The subtitle of Brodeur’s book indicates that he had climbed on the conspiracy theory bandwagon: “Power Lines, Computer Terminals, and the Attempts to Cover Up Their Threat to Your Health.” In a later book, subtitled “How the Utilities and the Government Are Trying to Hide the Cancer Hazard Posed by Electromagnetic Fields,” Brodeur (1993) continued the conspiracy theme. Brodeur’s writings brought to the attention of a wide public audience the claims and rumors that power lines caused cancer, which had been circulating for about ten years. Some of the claims were based on published epidemiological studies (i.e., Wertheimer and Leeper 1979), and others were based on what can best be called amateur epidemiology. In this case, individuals or groups with little or no training in data collection and analysis sought out evidence for a power line/cancer relationship. Evidence generated in this way was both the least reliable and the most emotionally compelling—a dangerous combination. Amateur epidemiology often starts when tragedy strikes a family, usually in the form of childhood cancer. The most common type of cancer in childhood is acute lymphoblastic leukemia (ALL). The cause of this type of cancer is unknown, which is obviously extremely frustrating to the parents of diagnosed children and in some cases starts a search for the cause of the cancer. As rumors about power lines began to spread, these lines became a handy and common target. After all, it was almost always easy to find a group of power lines somewhere near the affected child’s home, school, or playground. Equally, it was often possible to find groups of affected patients, a so-called cancer cluster, scattered over the landscape in space and time. And, of course, sometimes the cancer cluster seemed to coincide with areas with high concentrations of power lines. To the amateur epidemiologist, such coincidences of cancer clusters and power lines were all that was needed to prove that the power lines were causing the cancer. In fact, some individuals believed that the mere existence of cancer clusters by themselves proved that some environmental factor was responsible for cancer.

In reality, a causal association between an environmental factor such as power lines and a disease such as ALL requires a much higher standard of proof than just noting the presence of occasional coincidences. Clearly something is causing cancer in affected individuals. But even if causation was totally random over time and space, there would still be cancer clusters, due simply to the laws of chance. As an analogy, imagine a room twenty feet square divided into four hundred individual one-foot-square sections. Into this room we throw 1,600 marbles that come to rest at random throughout the room. Obviously, not every single one of the four thousand one-foot squares will end up with exactly four marbles in it. There will be some squares with lots of marbles and some with none. And yet there is no special “marble attractor” (i.e., depressions in the floor in some squares or some such) that causes more marbles to come to rest in certain squares. The laws of chance simply dictate that will be “marble clusters,” even in the absence of any nonchance factors.