The End of Doom (18 page)

In
Silent Spring,
Rachel Carson asked, “Who has decided—who has the
right
to decide—for the countless legions of people who were not consulted that the supreme value is a world without insects, even though it be also a sterile world ungraced by the curving wing of a bird in flight? The decision is that of the authoritarian temporarily entrusted with power.”

Banning DDT saved thousands of raptors over the past thirty years, but outright bans and misguided fears about the pesticide cost the lives of millions of people who died of insect-borne diseases like malaria. The 200 million people who come down with malaria and the 600,000 who die of the disease every year might well wonder what authoritarian made that decision.

DDT and Breast Cancer

In 2002, National Cancer Institute (NCI) researchers, in the most exhaustive study of its kind, could find no link between increased breast cancer rates and exposure to chemicals such as the pesticides DDT and chlordane or PCBs used as coolants in electrical transformers. This study is one more in a long line that can find no link between breast cancer and exposure to synthetic chemicals.

Human brains are adapted to be pattern recognition machines. Being able to recognize a tiger's stripes in a sun-dappled bamboo forest enhances one's chances of escaping its jaws. But it turns out that we over-recognize patterns. Our brains can find patterns in anything, which is why tarot cards and astrology remain popular. Researchers have shown that people will consistently claim to identify patterns in tables of randomly generated numbers. Just as our brains succumb to optical illusions, they fall victim to causality illusions.

Another point to keep in mind is that low-probability events do occur. Even if there is only a one in a million chance of something occurring to someone, with 7 billion people on the earth, it will occur 7,000 times somewhere. As the Internet reaches its tentacles further into human society, these odd occurrences have ever greater chances of being marveled at by wider and wider audiences.

From a public policy perspective, one of the most common and problematic misperceived patterns is cancer clusters. Every year we are treated to reports of communities that purportedly suffer more than their share of cancer. We all know the script by heart: Ten people in a small town are diagnosed with cancer—say, leukemia—within five years. Victims, reporters, regulators, and trial lawyers frantically search for a corporation manufacturing some allegedly toxic chemical nearby on which to pin the blame. The victims' suffering, it's assumed, must be the result of corporate greed.

This is exactly the script that played out on Long Island back in the 1990s. Under orders from Congress, the NCI conducted the most searching inquiry ever into an alleged cancer cluster and came up with exactly nothing. The NCI's Deborah Winn told
The
New York Times
the data “were very, very conclusive” that the synthetic chemicals studied “are not associated with breast cancer.”

Interestingly, another study, reported just a month earlier, did find a very high correlation between a risk factor and a woman's chances of getting breast cancer. That study confirmed that the longer a woman breast-fed, the lower her risk of getting breast cancer. Could it be that long-term breast-feeding was not fashionable among well-off suburban moms on Long Island two or three decades ago?

Fate or bad luck are not acceptable to us pattern-searching humans. What we once blamed on the malevolence of witchcraft, we now blame on the malevolence of corporations. In a sense, we are still in hot pursuit of witches.

We Are Now Living Long Enough to Get Cancer

As our deepening knowledge of biology is revealing, many of the human body's resources are aimed at keeping our cells' natural tendency to become cancerous at bay long enough for us to reproduce successfully. The plain, unavoidable fact of life is that our bodies' defenses against cancer break down as we age. It is true that high, prolonged exposures to some synthetic chemicals (or, in the case of cigarettes, natural chemicals) can cause cancer. But as the NCI epidemiologists found on Long Island, trace exposures to “environmental toxins” generally can't be linked to cancer. Nevertheless, our built-in drive to identify patterns will guarantee that we will continue to seek someone to blame for our ills and that we will suffer through many more expensive, unnecessary, and self-defeating witch hunts for a long time to come.

Even the US National Cancer Institute denies that there is a “cancer epidemic.” As the institute explains, the common misconception that we are experiencing a “cancer epidemic” stems largely from sensationalized media reports. “This only
appears
to be the case because the
number
of new cancer cases reported is rising as the population is both expanding and aging. Older people are more likely to develop cancer,” notes the institute. “So as more and more members of a 75-million-strong ‘baby-boomer' cohort begin shifting
en masse
to older, more cancer-prone ages, the
number
of new cancer cases is expected to increase in the next several decades.”

If you are male in the United States your lifetime risk of developing cancer is approximately 1 in 2, and your risk of dying of cancer is 1 in 4. If you are female your lifetime risk of contracting cancer is 1 in 3, and your risk of dying of malignancy is 1 in 5. Is an especially toxic environment responsible for these grim statistics? Actually, no. What these statistics signal is that you are likely to live a long time. If you live long enough you will get cancer.

A look back in time is instructive. In 2012, the
New England Journal of Medicine
published a fascinating article comparing the annual death rates between 1900 and 2010. The annual death rate in 1900 from the top ten causes of death was 1,100 per 100,000 (the all-cause death rate was just over 1,700 per 100,000). Of those deaths, more than half were caused by infectious diseases. Pneumonia or influenza killed 202 per 100,000; tuberculosis 194 per 100,000; gastrointestinal infections 143 per 100,000; and diphtheria 40 per 100,000. What about cancer? Cancer accounted for just 64 deaths out of 100,000 in 1900.

By 2010, the top ten causes of death killed just over half as many Americans, at the rate of about 600 per 100,000 (the all-cause death rate was just shy of 800 per 100,000). In the list of contemporary leading causes of death, infectious diseases hardly figure at all in the
New England Journal of Medicine
statistics. In fact, the infectious diseases listed are pneumonia and influenza, which kill 16 per 100,000 annually now. Cancer? In 2010, the disease caused 186 out of 100,000 deaths annually, triple the number in 1900. That initially sounds terrible until one considers the fact that only 47 percent of Americans lived past age sixty in 1900. Today, 88 percent of Americans live past age sixty.

The median age at which cancer is diagnosed is sixty-five, and 53 percent of all cancers are diagnosed in people over age sixty-five. Seventy percent are diagnosed in people over age fifty-five. In 1929, the first year for which the US Centers of Disease Control has national data, average life expectancy in the United States was fifty-seven years. Roughly speaking, this suggests that in the first decades of the twentieth century Americans were not living long enough for them to have developed around 75 percent of today's cases of cancer. That's why cancer was then comparatively rarer. And that's not taking into account the lower incidence rates that would likely have existed due to higher levels of physical activity and lower rates of obesity, cigarette smoking, and alcohol consumption that prevailed among Americans in the early part of the twentieth century. For example, the lung cancer death rate for men was just shy of 5 per 100,000 in 1930; by 1990, the rate had risen to 76 per 100,000.

Hormone Havoc: Half the Men Our Fathers Were?

While some environmental groups remain loyal to the old belief that exposures to trace amounts of synthetic chemicals are causing a cancer epidemic, others are now pushing the notion that these chemicals are generating hormone havoc. In
Silent Spring,
Carson does vaguely speculate that pesticide residues might increase endogenous estrogens, and she also worries about the exposures to synthetic estrogens in cosmetics, drugs, foods, and workplaces. She mentions in passing medical reports that suggest there is reduced sperm production among crop dusters. Nearly thirty years later, a group of Carson disciples meeting in 1991 at the Wingspread Center in Wisconsin under the auspices of the World Wildlife Fund developed their guru's suspicions about the effects of synthetic chemicals on sex hormones into the endocrine disruptor conjecture. The idea is that some synthetic chemicals harmfully produce the effects of estrogen, testosterone, and other hormones on human bodies and in wildlife.

I suspect the endocrine disrupting chemical (EDC) controversy will play out much the same way as the cancer controversy has. Basically it will turn out that some synthetic compounds in high doses will have deleterious effects on those exposed, but background exposures will have no detectable effects on the larger population.

As it happens, proponents of the idea that endocrine disruption is a major public health problem have issued a couple of consensus statements recently. For example, one such was issued in 2013 by a group working under the auspices of the United Nations Environment Programme.
The State of the Science of Endocrine Disrupting Chemicals
report begins by confidently asserting that many endocrine-related disorders are on the rise, including low semen quality and deformed penises, early breast development in girls, attention deficit and hyperactivity disorder in children, obesity and type 2 diabetes, and testicular, prostate, breast, and thyroid cancer. The “consensus” on all of these damaging effects was derived by combing selectively through the epidemiological literature. Interestingly, if you read through the data cited by the consensus architects, it becomes clear that the confident assertions in the
State of the Science
consensus are based on a lot of vigorous hand-waving and embarrassingly weak data.

For example, it bears noting that the
State of the Science
report itself admits that current research does not support the claim that synthetic endocrine disrupting chemicals are responsible for the trends that it identifies. The
State of the Science
report observes that “evidence linking estrogenic environmental chemicals with [breast cancer] is not available.” In addition, the
State of the Science
report acknowledges that “there is very little epidemiological evidence to link EDC [endocrine disrupting chemical] exposure with adverse pregnancy outcomes, early onset of breast development, obesity or diabetes.” Furthermore, the
State of the Science
report concedes, “There is almost no information about associations between EDC exposure and endometrial or ovarian cancer,” and “no studies exist that explore the potential link between fetal exposure to EDCs and the risk of testicular cancer occurring 20–40 years later.” Additionally, the
State of the Science
report notes that “high accidental exposures to PCBs [polychlorinated biphenyls] during fetal development or to dioxins in childhood increase the risk of reduced semen quality in adulthood.” If PCBs do lower sperm quality, it's a problem of the past rather than the future, since the production of PCBs was banned in the United States in 1979. Let's look beyond the feeble findings of the
State of the Science
report and see what other research has to say about the asserted trends.

Penis Problems and the Sperm Apocalypse?

Alarm about allegedly falling sperm counts due to exposure to synthetic estrogens was first raised in a 1992 article by Scandinavian researchers, who reported there had been a decline of nearly 50 percent in fifty years. Ever ready to fan the flames of panic, the publicists at Greenpeace quickly initiated a clever campaign of advertisements declaring, “You're not half the man your father was.”

Although the originators of the 1992 finding of falling semen quality and increasing penile anomalies continue to produce epidemiology to bolster those claims, many other researchers report contrary trends. For example, a 2013 comprehensive review of thirty-five sperm quality studies published after the purported decline was first announced in 1992 finds no such overall trend. The researchers report that eight studies involving a total of 18,109 men suggest a decline in semen quality; twenty-one studies encompassing 112,386 men show either no change or an increase in semen quality; and six studies involving 26,007 men show ambiguous or conflicting results. According to the researchers, the upshot is that “allegations for a worldwide decline in semen parameter values have not withstood scientific scrutiny.”

What about the epidemic of deformed penises that endocrine disruptors are supposedly engendering? One of the more common birth defects in males is hypospadias, in which the urethral opening occurs elsewhere along the penis rather than at the tip. A 2012 comprehensive review of data on trends for this birth defect reported that “generalized statements that hypospadias is increasing are unsupported” and that “firm conclusions cannot be made regarding the association of endocrine-disrupting exposures with hypospadias.” Another systematic review of studies looking for genetic and environmental influences on hypospadias found that “[w]hile genes involved in the aetiology of hypospadias have received a considerable amount of attention, research on environmental factors has been even more extensive. Despite the large number of studies, however, clear evidence for causal environmental factors is still lacking.”

A similar 2009 report, “Rising Hypospadias Rates: Disproving a Myth,” concluded, “A review of the epidemiologic data on this issue amassed to date clearly demonstrates that the bulk of evidence refutes claims for an increase in hypospadias rates.”