SCIENCE / HEALTH - LOOKING GLASS NEWS | |
Why We Can't Prevent Cancer: The Environmental Causes of Cancer |
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by PETER MONTAGUE Counter Punch Entered into the database on Friday, November 04th, 2005 @ 21:06:51 MST |
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In 1999, cancer surpassed heart disease as the number one killer of people younger
than 85 in the U.S.[1] Now a detailed report on the causes of cancer tells us
why: cancer has been steadily increasing in the U.S. for 50 years as people have
been exposed to more and more cancer-causing agents, including chemicals and radiation. Richard Clapp, Genevieve Howe, and Molly Jacobs Lefevre have just published
"Environmental
and Occupational Causes of Cancer; A Review of Recent Scientific Literature"
and it is a real eye-opener. But before we dive into this report looking for nuggets, let's set the background. About half of all cancer cases are fatal, and death by cancer is often prolonged,
painful, and very expensive. Those who manage to survive cancer live out their
lives molded by the after-effects of harsh treatments popularly known as "slash
and burn" -- surgery, chemotherapy, radiation, or some combination of the
three. As more people are kept alive each year with their breasts or testicles removed,
the "cancer establishment" chalks up another "victory" --
and no doubt the victims are glad to be alive -- but we should acknowledge that
there's something very wrong with calling this "victory." Slash and
burn seems more like a dreadful defeat. The truth is, an epic struggle has been going on for 50 years between the "slash
and burn=victory" camp, versus those who think the only real victory is
prevention of disease. The struggle occurs across a fault line defined by money.
To be blunt about it, there's no money in prevention, and once you've got cancer
you'll pay anything to try to stay alive. Cancer treatment is therefore a booming
business, and cancer prevention is nowhere. That is the basic dynamic of the
debate. Cancer surgeons can achieve the status of rock stars among their peers.
Those who advocate prevention will most likely find themselves without funding,
ridiculed and despised by the chemical industry, the pesticide industry, the
asbestos industry, the oil industry and all their minions -- lawyers, bankers,
engineers, reporters, professors, and politicians -- who make a fat living off
those who pump out cancer-causing products and dump out cancer-causing by-products,
aka toxic waste. The debate began 50 years ago when a powerful voice for prevention spoke out
from inside the National Cancer Institute (NCI). In 1948. Wilhelm Hueper, a
senior NCI scientist, wrote, "Environmental carcinogenesis is the newest and one of the most ominous
of the end-products of our industrial environment. Though its full scope and
extent are still unknown, because it is so new and because the facts are so
extremely difficult to obtain, enough is known to make it obvious that extrinsic
[outside-the-body] carcinogens present a very immediate and pressing problem
in public and individual health." In 1964, Hueper and his NCI colleague, W. C. Conway, described patterns in
cancer incidence as "an epidemic in slow motion": "Through a continued, unrestrained, needless, avoidable and, in part
reckless increasing contamination of the human environment with chemical and
physical carcinogens and with chemicals supporting and potentiating their
action, the stage is being set indeed for a future occurrence of an acute,
catastrophic epidemic, which once present cannot effectively be checked for
several decades with the means available nor can its course appreciably be
altered once it has been set in motion," they wrote.[pg. 28] Hueper of course was right. This is why 50% of all men and 40% of all women
in the U.S. now hear the chilling words, "You've got cancer" at some
point in their lives. That's right, 1 out of every 2 men now get cancer in the
U.S., and more than 1 out of every 3 women. Clapp, Howe and Lefevre tell us that between 1950 and 2001 the incidence rate
for all types of cancer increased 85%, using age-adjusted data, which means
cancer isn't increasing because people are living longer. People are getting
more cancer because they're exposed to more cancer-causing agents. Contrary to well-funded rumors, the culprit isn't just tobacco or the hundreds
of toxic chemicals intentionally added to tobacco products. Tobacco products
remain the single most significant preventable cause of cancer, but they have
not been linked to the majority of cancers nor to many of the cancers that have
increased most rapidly in recent decades including melanoma, lymphomas, testicular,
brain, and bone marrow cancers.[pg. 1] No, it's more complicated than just tobacco with its toxic additives. Most
plastics, detergents, solvents, and pesticides and the toxic-waste by-products
of their manufacture came into being after World War II. From the late 1950s
to the late 1990s, we disposed of more than 750 million tons of toxic chemical
wastes.[pg. 27] Over 40 years, this represents more than two tons of toxic chemical
wastes discharged into the environment for each man, woman and child in the
U.S. No wonder some of it has come back to bite us. Since the U.S. EPA began its Toxics Release Inventory (TRI) program in 1987,
total releases have been reported as declining (though EPA does not check the
accuracy of industry's self-reporting). Despite the reported decline, in 2002,
the most recent year reported, 24,379 facilities in the U.S. reported releasing
4.79 billion pounds of over 650 different chemicals. (And TRI data do not include
other enormous discharges: toxic vehicle emissions, the majority of releases
of pesticides, volatile organic compounds, and fertilizers, or releases from
numerous other non-industrial sources.) In 2001, more than 1.2 billion pounds
of pesticides were intentionally discharged into the environment in the United
States and over 5.0 billion pounds in the whole world.[pg. 27] While all this chemical dumping has been going on, incidence rates for some
cancer sites have increased particularly rapidly over the past half century.
From 1950-2001, melanoma of the skin increased by 690%, female lung & bronchial
cancer increased by 685%, prostate cancer by 286%, myeloma by 273%, thyroid
cancer by 258%, non-Hodgkin's lymphoma by 249%, liver and intrahepatic duct
cancer by 234%, male lung & bronchial cancer by 204%, kidney and renal pelvis
cancers by 182%, testicular cancer by 143%, brain and other nervous system cancers
by 136%, bladder cancer by 97%, female breast cancer by 90%, and cancer in all
sites by 86%.[pg. 25] In the most recent 10-year period for which we have data (1992-2001), liver
cancer increased by 39%, thyroid cancer increased by 36%, melanoma increased
by 26%, soft tissue sarcomas (including heart) by 15%, kidney and renal pelvis
cancers by 12%, and testicular cancer increased by 4%.[pg. 25] OK, so dumping chemicals into the environment has been a major industrial pastime
for 50 years, and cancers are increasing. But why do we think these things are
connected? What real evidence do we have that environmental and occupational
exposures contribute to cancer? That's what the new Clapp-Howe-Lefevre report is about. It is a review of recent
scientific literature -- with emphasis on human studies, not studies of laboratory
animals. Indeed, the bulk of the new Clapp-Howe-Lefevre report is a cancer-by-cancer
compendium of what recent human studies tell us about environmental and occupational
exposures that contribute to cancers of the bladder, bone, brain, breast, cervix,
colon, lymph nodes (Hodgkin's disease and non- Hodgkin's lymphoma), kidney,
larynx, liver and bile ducts, lungs, nasal passages, ovaries, pancreas, prostate,
rectum, soft tissues (soft tissue sarcoma), skin, stomach, testicles, and thyroid,
plus leukemia, mesothelioma, and multiple myeloma. (It is worth pointing out
-- and Clapp-Howe-Lefevre do point it out -- that this compendium owes a great
debt to a data
spreadsheet on cancer and its environmental causes prepared by Sarah Janssen,
Gina Solomon and Ted Schettler, for which thanks are due the Collaborative
on Health and Environment.) Many of the bad actor chemicals are well-known to us all: metals and metallic
dusts (arsenic, lead, mercury, cadmium, hexavalent chromium, nickel); solvents
(benzene, carbon tet, TCE, PCE, xylene, toluene, among others); aromatic amines;
petrochemicals and combustion byproducts (polycyclic aromatic hydrocarbons,
or PAHs); diesel exhaust; ionizing radiation (x-rays, for example); non-ionizing
radiation (magnetic fields, radio waves); metalworking fluids and mineral oils;
pesticides; N-nitroso compounds; hormone-disrupting chemicals (found in many
pesticides, fuels, plastics, detergents, and prescription drugs); chlorination
byproducts in drinking water; natural fibers (asbestos, silica, wood dust);
man-made fibers (fiber glass, rock wool, ceramic fibers); reactive chemicals
(such as sulfuric acids, vinyl chloride monomer, and many others); petroleum
products; PCBs; dioxins; mustard gas; aromatic amines; environmental tobacco
smoke; and outdoor air pollution. But there is additional evidence linking chemicals with cancer: * Elevated cancer rates follow patterns -- the disease is more common in
cities, in farming states, near hazardous waste sites, downwind of certain
industrial activities, and around certain drinking-water wells. Patterns of
elevated cancer incidence and mortality have been linked to areas of pesticide
use, toxic work exposures, hazardous waste incinerators, and other sources
of pollution.[pg. 26] * The U.S. EPA's long-delayed and heavily industry-influenced "Draft
Dioxin Reassessment" released in 2000 admitted that the weight of the
evidence from human studies suggests that, "the generally increased risk
of overall cancer is more likely than not due to exposure to TCDD [dioxin]
and its congeners [chemical relatives]." The report goes on to conclude,
"The consistency of this finding in the four major cohort studies and
the Seveso victims is corroborated by animal studies that show TCDD to be
a multisite, multisex, and multispecies carcinogen with a mechanistic basis."[pg.
26] * Farmers in industrialized nations die more often than the rest of us from
multiple myeloma, melanoma, prostate cancer, Hodgkin's lymphoma, leukemia,
and cancers of the lip and stomach. They have higher rates of non-Hodgkin's
lymphoma and brain cancer. Migrant farmers experience elevated rates of multiple
myeloma as well as cancers of the stomach, prostate, and testicles.[pg. 26] * The growing burden of cancer on children provides some of the most convincing
evidence of the role of environmental and occupational exposures in causing
cancers. Children do not smoke, drink alcohol, or hold stressful jobs. Their
lifestyles have not changed appreciably in recent years. In proportion to
their body weight, however, "children drink 2.5 times more water, eat
3 to 4 times more food, and breathe 2 times more air" than adults."
In addition, their developing bodies may well be affected by parental exposures
prior to conception, exposures while growing in the uterus, and the contents
of breast milk. Clapp-Howe-Lefevre put it this way: "We have learned how to save more lives, thankfully, but more children
are still diagnosed with cancer every year. The incidence of cancer in all
sites combined among children ages 0-19 increased by 22% from 13.8/100,000
in 1973 to 16.8 in 2000 and most of this increase occurred in the 1970s and
1980s. Epidemiologic studies have consistently linked higher risks of childhood
leukemia and childhood brain and central nervous system cancers with parental
and childhood exposure to particular toxic chemicals including solvents, pesticides,
petrochemicals, and certain industrial by-products (namely dioxins and polycyclic
aromatic hydrocarbons [PAHs])."[pg. 26] All in all, the Clapp-Howe-Lefevre report makes a compelling case that many
industrial chemicals contribute to many kinds of cancers. But where this report
really shines is in its clear call for prevention. In all,
there are relatively few products or substances associated with cancer.[pgs.
10-11, 37-40] Everything doesn't cause cancer, and many of the things that do
could be shunned and phased out. In principle, a great deal of prevention is
possible. Thirty years into the prevention-vs-treatment debate -- in 1981 -- two famous
British scientists -- Sir Richard Doll and Sir Richard Peto -- published an
extremely influential study in which they estimated that "only" 2
to 4% of all cancers are caused by environmental or workplace exposures. With
1.2 million new cases of cancer each year in the U.S., half of them fatal, 2%
to 4% = 12,000 to 24,000 deaths each year, most of them preventable. Doll and
Peto said tobacco caused 30% of all cancers and food caused another 35%. We
now know that cancer results from the interaction of our genes with exposure
to several cancer-causing agents. All the necessary exposures must occur to
cause a cancer -- if any one of them is missing, the cancer will not occur.
This is why prevention is important -- it really can work. Because cancer requires multiple exposures to cancer-causing agents, it is
wrong and misleading to say that "Exposure to product A causes X percent
of all cancers." It simple doesn't work like that. Perhaps Doll and Peto
in 1981 did not know how such things worked, and they boldly proceeded to estimate
what percent of all cancers were attributable to particular exposures. It was
wrong, but their report served as powerful ammunition for the prevention-is-pointless
crowd. If "only" 2 to 4% of all cancers were caused by environmental
exposures, then there was little incentive to prevent human exposure to environmental
agents, the argument went. What a welcome message this was for the cancer-creation
industries (petrochemicals, metals, pesticides, asbestos, radiation, and others)
and for the cancer treatment industry! Damn the torpedoes -- full speed ahead! The prevention-is-pointless crowd latched onto the Doll and Peto study and
spread it everywhere. By the end of 2004, the original 1981 Doll-and-Peto paper
had been cited in 441 subsequent scientific papers.[pg. 4] But even more importantly,
the federal National Cancer Institute and the American Cancer Society (which,
together, you could call the "cancer establishment") adopted the Doll-Peto
perspective, that cancer is a lifestyle disease -- the victims themselves are
responsible -- and that prevention of environmental and occupational exposures
is not worth the effort. Remember this was the beginning of the Reagan counterrevolution
and the Doll-Peto paper fit right into the new ideology -- government is bad,
big corporations are good, we're all individually responsible for whatever bad
things happen to us, and greed is good because it makes the world go 'round.
In any case, the NCI and the ACS largely adopted the Doll-Peto perspective,
and they poured the bucks into new cancer treatments, pretty much ignoring prevention.
Meanwhile, cancer incidence rates climbed relentlessly -- making the cancer-treatment
industry healthier and wealthier, which allowed it to further erode support
for prevention. Now we are starting to shake off the stupor induced by the misleading Doll-Peto
arithmetic, which pretended to prove that environment and occupational exposures
are of no consequence. Listen to this marvelously clear-eyed conclusion from the Clapp-Howe-Lefevre
report: "Comprehensive cancer prevention programs need to reduce exposures from
all avoidable sources. Cancer prevention programs focused on tobacco use,
diet, and other individual behaviors disregard the lessons of science."[pg.
1] And this: "Preventing carcinogenic exposures wherever possible should be the goal
and comprehensive cancer prevention programs should aim to reduce exposures
from all avoidable sources, including environmental and occupational sources."[pg.
6] And this: "Further research is needed, but we will never be able to study and
draw conclusions about the potential interactions of exposure to every possible
combination of the nearly 100,000 synthetic chemicals in use today. Despite
the small increased risk of developing cancer following a single exposure
to an environmental carcinogen, the number of cancer cases that might be caused
by environmental carcinogens is likely quite large due to the ubiquity [presence
everywhere] of carcinogens. Thus, the need to limit exposures to environmental
and occupational carcinogens is urgent."[pg. 29] And this: "The sum of the evidence regarding environmental and occupational contributions
to cancer justifies urgent acceleration of policy efforts to prevent carcinogenic
exposures. By implementing precautionary policies, Europeans are creating
a model that can be applied in the U.S. to protect public health and the environment.
To ignore the scientific evidence is to knowingly permit tens of thousands
of unnecessary illnesses and deaths each year."[pg. 1] What a blast of fresh air! The latest strategy from the cancer-creation industries is to claim that we
can't take action to prevent environmental and occupational exposures because
we don't have enough information. We're simply too ignorant to make a move.
More study is needed. Clapp-Howe-Lefevre allow the eloquent writer Sandra Steingraber
to answer this argument. They say, "A main concern for Sandra Steingraber,
author of Living
Downstream: An Ecologist Looks at Cancer and the Environment, is not whether
the greatest dangers are presented by dump sites, workplace exposures, drinking
water, food, or air emissions: "I am more concerned [writes Steingraber] that the uncertainty over
details is being used to call into doubt the fact that profound connections
do exist between human health and the environment. I am more concerned that
uncertainty is too often parlayed into an excuse to do nothing until more
research can be conducted."[pg. 29] Clapp, Howe and Lefevre go on: "At the same time, uncertainty and controversy
are permanent players in scientific research. However, they must not deter us
from enacting regulations and policies based on what we know and pursuing the
wisdom of the precautionary principle. This is not new thinking, as demonstrated
by Sir Austin Bradford Hill's 1965 address to the Royal Society of Medicine: "All scientific work is incomplete [wrote Sir Austin Bradford Hill]
-- whether it be observational or experimental. All scientific work is liable
to be upset or modified by advancing knowledge. That does not confer upon
us a freedom to ignore the knowledge we already have, or to postpone action
that it appears to demand at a given time."[pg. 29] Clapp, Howe and Lefevre then offer some guidelines for preventive action: (1) The least toxic alternatives should always be used. (2) Partial, but reliable, evidence of harm should compel us to act on the
side of caution to prevent needless sickness and death. (3) The right of people to know what they are being exposed to must be protected. Clapp, Howe and Lefevre observe that "the United States has much to learn"
from the proposed European chemicals policy, known as REACH: (1) requiring that industry be responsible for generating information on
chemicals, for evaluating risks, and for assuring safety; another way of saying
this is, "No data, no market." (2) extending responsibility for testing and management to the entire manufacturing
chain -- everyone who uses a chemical has a duty to familiarize themselves
with the consequences; (3) using safer substitutes for chemicals of high concern; and, (4) encouraging innovation in safer substitutes.[pg. 29] In the words of ecologist Sandra Steingraber: "It is time to start pursuing
alternative paths. From the right to know and the duty to inquire flows the
obligation to act."[pg. 29] But while we're working in clear-eyed mode here, let's take our exploration
a bit further and look this problem squarely in the face. The U.S. economy and culture are premised on endless growth. If I loan you
$100 in the expectation that you will pay me back $103 next year, that extra
3% must come from somewhere. That "somewhere" has physical dimensions
-- something must be dug up or grown to produce the additional 3%. That something
must also be moved, processed, moved again, packaged, promoted and sold, moved
again, used, moved again, and eventually discarded. Even if it is recycled many
times, ultimately it will be discarded into a natural ecosystem somewhere (at
which point nature begins moving it once again). The inescapable second law
of thermodynamics tells us that each of these steps will inevitably be accompanied
by waste, disorder and other disruptive unintended consequences. Even if you
create the extra 3% per year by providing a "service" instead of a
"product," you still require food, water, shelter, energy, clothing,
tools, transportation, commercial space, medical care, municipal support services
(like police, fire, emergency services, and sewage treatment), leisure activities,
communications and information, schooling, and on and on. An economy that is growing at 3% per year is doubling in size every 23 years
-- requiring, every 23 years, a doubling in the number of cities, food sources,
mines, factories, power plants, vehicles, highways, parking lots, schools, sewage
treatment plants, hospitals, prisons, discards, trash and dumps. For a very
long time this kind of rapid growth seemed tolerable. But now things are different
-- the earth is full of people and their artifacts. We can no longer throw things
"away" without affecting someone somewhere. Something else is new as well. The modern, globalized financial environment
(in which money flows easily across international borders), creates tremendous
competitive pressure to attract investment by increasing return to investors.
That in turn creates pressure to pass costs along to the general public. Economists
call it "externalizing" costs. If I dump my chemicals and make you
sick, I gain if I can get you to pay your own medical bills, and I gain again
if I can get taxpayers to clean up my mess. Firms have a natural incentive to
externalize their costs to the extent possible, but the present "globalized"
financial environment has increased that incentive greatly, to improve return
to investors. In sum, let us review the pressures that prevent prevention. (1) In general, it is difficult to make prevention pay, but remediation can
pay handsomely; this is certainly true for the cancer industry. In general,
financial-political-legal incentives are set up to reward those who create
problems and those who supply remedies. (2) Economic growth entails the continual creation of ever-more and ever-larger
messes. Even if we managed to "green" commerce in every way we can
think of today, damage to nature would still be roughly proportional to the
size of the human economy because the second law of thermodynamics cannot
be evaded. And we now know that damage to nature gives rise to human disease
in myriad ways. Now that the earth is full, a growing economy creates palpably-growing
health problems, including immune system degradation giving rise to cancers. (3) The modern economy creates irresistible pressure to increase stock prices,
which in turn creates relentless pressure to externalize costs by hook or
by crook. So let's not kid ourselves. Yes, cancer must be prevented
because for the most part it can't be cured -- it can only be slashed and burned
away at enormous cost, personal, social and monetary. But saying cancer must be prevented is one thing. Expecting
that it can be prevented within the framework of the modern
economy is another. We can never stop working to prevent cancer -- and precautionary
policies will always make sense no matter what kind of economy we have -- but
until we shift to an economy that doesn't require growth, we'll find ourselves
right where we are now -- on an accelerating rat wheel. As a result, we can
expect to be living with more and more cancer at greater and greater cost to
ourselves and to our children, accompanied by ever-increasing pain. It is not
a pretty picture. But at least we can now see it clearly. |