The Cancer Chronicles (14 page)

During the next two decades land bordering the canal was sold and developed, and in the late 1970s, after a couple of years of unusually high precipitation, residents began to complain of a sickening smell. When an official from the
Environmental Protection Agency came to inspect in 1977, he saw rusting barrels of waste that had found their way to the surface. Potholes were oozing waste into several backyards, and it had seeped into the basement of one home. “
The odors penetrate your clothing and adhere to your footwear,” the official reported. Three days later his sweater still stank. The neighborhood was evacuated, a national emergency declared, and the investigations began.

Whole books have been written attempting to apportion blame among Hooker, the school board, the real estate developers, and the city of Niagara Falls for what everyone agrees was an environmental disaster. (
Joyce Carol Oates
incorporated the saga into a novel.) Just as difficult has been determining the damages caused by the dump to public health. Early in the crisis,
the EPA estimated that people living along Love Canal stood a 1 in 10 chance of getting cancer during their lives just from breathing the polluted air. But
several days later the agency
admitted to a mathematical error: the increased risk was actually 1 in 100 and far less for people just a few blocks away.
Another EPA report found that some of the thirty-six residents who volunteered for tests showed signs of
chromosomal damage—more than considered normal. But it was
dismissed by a panel of medical experts led by
Lewis Thomas, chancellor of
Memorial Sloan-Kettering
Cancer Center, as “inadequate” and so poorly executed that it “damaged the credibility of science.”
A later study for the Centers for Disease Control found no excess of chromosomal aberrations.

Cancer can take decades to develop, and those who continued to follow the case awaited the results of
a thirty-year retrospective by the New York State Department of Health. With so many variables to juxtapose, studies like this are fraught with uncertainty. Age, sex, and proximity to the canal had to be taken into account.
Almost half of the 6,026 residents who were surveyed worked in jobs where occupational exposure might be a risk, and about two-thirds of them had been smokers. About the same proportion drank alcoholic beverages.

When the study was complete, the epidemiologists reported that
the birth defect rate for children born to parents who had lived near the canal was double that of Niagara County and also
higher than for the rest of the state. Compared with the population at large,
slightly more girls had been born than boys—another hint that Love Canal chemicals may have had
genetic influences. Despite the hints of teratogenic effects, the study found
no convincing evidence that life by the canal had given people cancer. A few types of cancer were slightly more prevalent than expected but the numbers were so small that they were considered within the range of chance. The
overall cancer rate was actually a little lower than for the general population.

Birth defects and cancer can both arise from mutations, so why would there be signs of one without the other? It seems plausible that the dividing cells of a developing embryo would be more sensitive to disruptive influences than cells in a fully formed person. And while a
single mutation might be enough to derail a developmental pathway, several of these hits would usually be required for a cell in an organ to break away and become cancerous. But even after three decades, the seeming head start provided by Love Canal hadn’t been enough to produce an obvious excess of malignancies.

For many of us who grew up during the exuberant beginnings of the
environmental movement of the 1970s and 1980s, that outcome was almost beyond belief. We were influenced by
Silent Spring,
Rachel Carson’s elegant warning about pesticides and the environment, and
scathing polemics like
Samuel Epstein’s
The
Politics of Cancer.
We worried about
saccharine and
Red Dye No. 2, and later about
Alar on apples. We were told of
a modern epidemic of cancer—“
the plague of the twentieth century”—that was being imposed on the public by irresponsible corporations and their effluents. Food additives, pesticides and herbicides, household cleaners—all of these were said to be corrupting our
DNA. We were pawns in “
a grim game of
chemical roulette,”
Russell Train, the administrator of the EPA, warned in a story that was picked up by newspapers across the country. “Strange new creatures of our own making are all around us, in our air, our water, our food and in the things we touch. When they hit us, we don’t feel a thing. Their ill effects may not show up until decades later, in the form of cancer or even generations later in the form of mutated genes.” We were in the midst of what the historian
Robert Proctor called “
the
Great Cancer Wars.”

Ninety percent of cancer is environmental
—we heard that again and again. There was a conspiratorial bent to some of the warnings: the same companies that produced the carcinogenic chemicals also made the drugs used for the chemotherapeutic cures. They were profiting from cancer on both ends. Rhetoric like that was extreme, but the overall message seemed so plausible. Many manufactured chemicals are considered carcinogenic. They can be found among the
known and suspected agents listed in the
National Toxicology Program’s 499-page
Report on Carcinogens.
Depending on the degree of exposure, workers in industries that use or produce these substances
take on an increased health risk. As the
chemicals diffused through the atmosphere, severe effects on the public were bound to become evident—beginning in the present and escalating year by year with the accumulation of broken genes.

Some of our fears were rooted in a misunderstanding. Epidemiologists define “environment” very broadly to include everything that is not the direct result of heredity—smoking, eating, exercise, the bearing of children, sexual habits, any kind of behavior or cultural practice.
Viruses, exposure to sunlight, radon, cosmic rays—these are all defined as
environmental.
To get a sense of how strongly
cancer was influenced by heredity and how strongly by these extrinsic factors, scientists in the 1950s studied populations of black people whose ancestors had been captured by slave traders and moved to the United States and compared them with their relatives who remained in
Africa.
Liver cancer and
Burkitt’s lymphoma turned out to be very high among the
Africans but not among the American blacks.
Lung, pancreatic,
breast,
prostate, and other cancers were far higher among the black Americans than the Africans. Other researchers found similar patterns.
Japanese men were known to have higher rates of
stomach cancer but lower rates of
colon cancer compared with their counterparts in the United States. When they moved to this country, the situation changed. They tended to adopt the cancers of their hosts and leave the native cancers behind. Since their genes remained the same, factors beyond heredity had to be involved.

By the late 1970s decades of these
migrant studies had come to the same conclusion: For 90 percent of cancer cases some kind of external influence was required. Something “environmental.” There was a chance of a person getting a head start on cancer by inheriting a damaged gene. But most of the mutations that triggered a malignancy were those acquired during life. That was encouraging news for public health and prevention. But it was often misconstrued to mean that almost all cancer was brought on by
pollution,
pesticides, and industrial waste. That fit so perfectly with the rest of our worldview that there was little incentive to look deeper. Calmer voices
called for a more balanced perspective, but it was the direst warnings that became enshrined in public perception. If we or someone we knew ever got
cancer we were quick to wonder whether corporate America was to blame.

There was more to the story than
politics and semantics. In 1973, not long after
Richard Nixon declared the
War on Cancer, the government
Surveillance, Epidemiology and End Results Program, called SEER, began collecting data from state cancer registries on incidence and mortality—how frequently people got cancer and how often it killed them. For years the mainstream view had been that except for lung cancer, overall rates were holding steady. But in 1976 when the new SEER data were compared with earlier surveys by the
National Cancer Institute, the number of new cases
seemed to be escalating abruptly, even when the aging of the population was allowed for. This
appeared to be the vindication so many people sought.

Combining two sets of statistics, compiled from different sources according to different rules, is bound to cause trouble. Early on epidemiologists
warned that the comparisons were invalid and no conclusions should be drawn—that there was no evidence of a cancer
epidemic. To get a clearer idea of what the public was facing, the U.S. Office of
Technology Assessment
commissioned a study by
Richard Doll and
Richard Peto, two Oxford University epidemiologists who had made names for themselves by establishing the link between cigarettes and cancer as well as the carcinogenic effects of asbestos. It would have been hard to find two more
accomplished scientists in their field.

To begin with, they had to decide
which numbers to trust. Although they were improving, statistics on cancer incidence—the number of new cases occurring in a population—were not yet dependable. What appeared to be more new cancers might be the result of better diagnostics, more accurate medical records, and an ever-increasing proportion of the population seeking and receiving medical care. Death certificates from earlier in the century were
also suspect. Doctors might acquiesce to a family’s request that the stigma of
cancer not be entered into the public ledgers. Mistakes in both record keeping and diagnosis were often made. Someone who died of
lung cancer might be listed as a victim of pneumonia. A death from an undiagnosed brain tumor might be attributed to senility. A patient might be recorded as dying of cancer when the cause was really something else.
The situation improved in 1933 when states began reporting deaths to a central registry, and midway through the century a standardized
classification scheme was put in place. (Cervical and
uterine cancer had been lumped together, and
Hodgkin’s lymphoma, a blood cell malignancy, was misconstrued as an infectious disease.) Starting with 1950 and using death rates as the best available approximation for the prevalence of cancer, the authors produced an intricate analysis spanning more than a hundred densely filled pages of words, tables, and graphs and six meticulous appendices. In addition to their own calculations they also reviewed the findings of more than three hundred other studies.

Since it was published in 1981, Doll and Peto’s “The
Causes of Cancer” has become one of the most influential documents in cancer epidemiology. It concluded that most cancer, by far, is “avoidable”—brought on by factors that, to a great extent, are within the grasp of human control.
In 30 percent of cancer deaths, tobacco was a cause. For diet the proportion was 35 percent, and for alcohol it was 3 percent. Some 7 percent of fatalities involved “reproductive and
sexual behavior,” which included delaying or forgoing the bearing of children and promiscuous sex. (Having multiple partners was recognized as a risk for
cervical cancer, although it was not yet known that the agent was human
papillomavirus.) Another 10 percent of cancer was tentatively attributed to various infections and 3 percent to “geophysical” phenomena: exposure to the ultraviolet components of sunlight and naturally occurring background
radiation from soil and cosmic rays. For deaths by
artificially produced carcinogens, including radioisotopes, the percentages came out very low: 4 percent from occupational exposure, 2 percent from air, water,
and food
pollution, 1 percent from the side effects of medical treatment (including x-rays and
radiotherapy), and less than 1 percent from either industrial products like paints, plastics, and solvents or food additives. The remainder was of unknown origin with the suggestion that psychological stress or a
compromised immune system might be involved. Except for
lung
cancer, Doll and Peto concluded, “
most of the types of cancer that are common today in the United States must be due mainly to factors that have been present for a long time.”

What a hard conclusion this was to swallow.
Any specific case of cancer will have multiple causes—environmental (in the broadest sense) along with hereditary dispositions and the elusive influence of bad luck. But for the public at large,
chemicals spewed from factories or the polysyllabic additives found in foods were apparently only minor parts of the equation.
They were a component—“
there is too much ignorance for complacency to be justified,” the authors wrote—but far more important was how we lived and the effect that had on a cell’s natural tendency to break loose and assert its Darwinian imperative. Most telling of all, Doll and Peto found that cancer had not been increasing rapidly, as one would expect if we were being subjected to an efflorescence of newly invented assaults. When lung cancer and other malignancies closely associated with smoking (oral, laryngeal, esophageal, and others) were removed from consideration, and the aging of the population adjusted for,
cancer mortality among people under sixty-five had been steadily decreasing in almost every category since 1953. (That also appeared to be
largely true for older Americans, but those figures, relying on earlier medical and census reports, were considered less reliable.) The lower mortality was
not because we were getting much better at curing cancer, the authors concluded, but because the number of new cases was not escalating. Once SEER became better established and the quality of data improved, they confirmed that there was no alarming rise in the incidence of cancer.

Doll and Peto were not alone in their findings.
Two smaller studies,
one in the United States and one for the industrial city of
Birmingham, England, had come up with similar percentages—with most
cancer attributed to smoking and a mix of other so-called lifestyle factors and with occupational exposure responsible for only a few percent. But “The Causes of Cancer” was the most wide-ranging study that had been undertaken. Its conclusions were, of course, what the leaders of industry wanted to hear, and people committed to fighting the problems of industrial pollution
began challenging the report. The lifestyle argument was dismissed as a diversion—blaming the victims instead of the perpetrators. While cigarettes were clearly an important influence, maybe a significant number of smokers wouldn’t have gotten lung cancer without additional help from polluted air or synthetic carcinogens—some knotty synergistic effect. Whatever was happening with overall rates, the incidence of some cancers appeared to be rising, especially among the aged and minority groups. Maybe what Doll and Peto laid to better diagnosis were really hints of carcinogenic poisons that were steadily accumulating and would erupt in coming years in a devastating outbreak of cancer.
When lung cancer rates began rising earlier in the twentieth century, that was also dismissed as an artifact of better diagnostics. Only with time would the true horror we were inflicting on ourselves become clear.