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Not too long ago a story about a study examining mummies for the prevalence of cancer caused a flurry of articles in the media claiming that cancer is a man-made disease. The researchers claim that cancer was very rare in ancient egypt compared to modern times.

In their press release about the study the author states

“In industrialised societies, cancer is second only to cardiovascular disease as a cause of death. But in ancient times, it was extremely rare. There is nothing in the natural environment that can cause cancer. So it has to be a man-made disease, down to pollution and changes to our diet and lifestyle.”

Are those claims valid? What evidence is there about the environmental causes of cancer? I'm not just asking about this specific study, but also about other studies showing how important environmental factors are in the incidence of cancer.

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    I’m astonished that the University would issue such a seriously flawed press release. This considerably calls into question the integrity of the study in the first place. Whether or not the study has some validity, the press release is just bad. – Konrad Rudolph Mar 21 '11 at 19:58
  • Wow – I’m just noticing that MSNBC is basically saying the same thing as I, and even sourcing their claims (well, some of them). They really did their homework. – Konrad Rudolph Mar 21 '11 at 20:00
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    Konrad, are you saying that your knowledge of cancer is better than the Manchester University researchers? Maybe you should cite the papers you have published on the subject. – DJClayworth Mar 22 '11 at 15:52
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    @DJClayworth Please focus on the arguments here, not on the users. There is often a big difference between the peer-reviewed paper and the press-release about it, you don't need extensive credentials to poke holes into exaggerated press releases, those are unfortunately far too common. – Mad Scientist Mar 22 '11 at 21:51
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    @DJClayworth I did not publish any studies on the topic, nor do I need to. Do I need to publish studies to ridicule a researcher who claims that π = 3? No. The claim that “[t]here is nothing in the natural environment that can cause cancer” is just as ridiculously wrong. See the answers for examples. Furthermore, if I were the author of a study that was praised by such a press release, I would mount the barricades. In the best case, this is a gross misinterpretation of the study. I the worst case, it’s an accurate representation. – Konrad Rudolph Apr 28 '11 at 0:12
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I know of no studies but it is well-known that

  1. life expectancy has increased drastically since ancient Egypt and that
  2. cancer prevalence increases with age.

About the first point, life expectancy in ancient Egypt was around 25 years, and even in the middle ages no more than 30 years. Compare that to today’s 67 years. Granted, once you take infant mortality out of the equation life expectancy grows – but it still was much less than today, and more importantly, it was often less than 50 years.

The second point is due to a number of factors but it all boils down to cell aging and accumulating effects of detriment mutations. There are occurrences of cancer in young people and even in children, but mostly, it is “a disease found in people over the age of 50”: according to SEER data, just 95 people below 50 get cancer for 1449 incidences above 50.

Combined, it isn’t surprising to see that cancer is much more common now than it was then. Superficially, no further reasons are needed to explain this phenomenon.

Furthermore, animals (e.g. chimpanzees) and even plants can get cancer, too – so this isn’t a problem that is partial to humans (though that doesn’t preclude new environmental causes).

Apart from that, the quote is complete nonsense:

There is nothing in the natural environment that can cause cancer

Well … no. There are a lot of things in the natural environment that can and do cause cancers. The most glaring point is natural sources of high radiation, such as uranium ore and of course the sun. But more sources exist, such as viruses, infectious diseases and diet.

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    Don't forget the sun. – Borror0 Mar 21 '11 at 20:14
  • @Borror0 Good point, added. – Konrad Rudolph Mar 21 '11 at 20:18
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    Also, important to consider the diagnose bias. I'm quite sure nobody in ancient egypt knew what a cancer was and if someone died from it, they would have just assumed he was cursed or something. – Stefano Borini Mar 21 '11 at 20:54
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    While I largely agree with your conclusions, life expectancy was so low because infant mortality was so high. If somebody lived to be 5 years old, they'd probably live to be at least 40 or 50. – Gabe Mar 22 '11 at 7:03
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    I read the same article: "a Roman Life Expectancy table at the University of Texas shows that at birth the life expectancy was 25 but if one lived to the age of 5 one's life expectancy jumped to 48." – Gabe Mar 22 '11 at 12:05
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Before I start, I always remind people that cancer is NOT one specific illness with one specific cause or treatment. In fact, most people would be amazed at how many types of cancer there are.

One of the first depictions of cancer in historical medical literature dates back to about 1600 BC, from what's known as the Edwin Smith Papyrus. For a historical overview, the Journal of Surgical Oncology has a paper here.

The name "cancer" was attached to various malignancies by Hippocrates, from whom we have documented cases from ancient Greece. So, the first answer is simple: No, cancer is not a modern, man-made disease.

As for the quote posted, I would like to point out a simple flaw in what seems to be the central statement of this argument: "There is nothing in the natural environment that can cause cancer". This is easily falsifiable. I think most rational people would agree that there are few things more natural than SUNLIGHT. Of course, there is a fairly well-documented association between sun exposure and melanoma. There are also known viral causes of cancer, the most well known being HPV. While we may not like to think of a virus as a pleasant thing, it is in fact perfectly all-natural.

Any sufficient analysis of cancer rates is going to be much too complex for a simple post, but I can suggest some places to begin research, if one is so inclined.

For some data as to current trends; you can find a table of death rates for males and females between 1930-2006. There is also a nicely put together table here for cancer probabilities for 2004-2006 broken down by age, sex, and organ.

The NCI offers a searchable database of available statistics from the SEER which should also provide a good place to start looking if one is curious.

Remember that cancer is a hot-button issue in the media, and what is reported in the general press may not accurately reflect the current state of the peer-reviewed legitimate research. Search out the citations if you can and see for yourself.

Also keep in mind that studying prevalence and incidence rates for cancer is very time-consuming and labor-intensive. One must take into consideration many factors in order to properly interpret the data. Some confounding factors are:

  • Increased diagnostic capabilities which allow modern medicine to find and diagnose more cancers.

  • Increased lifespan which allows for more time to develop cancer

  • Immunosuppressive conditions such as HIV which make patients more susceptible to cancers.

  • Better survival rates for cancers which increase the number of cases in the general population.

This is obviously not a complete answer, but I hope it was helpful as a place to begin.

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    Not only there are many types of cancer, but the "same type" (e.g. breast cancer) can also derive from different causes and, at the end, be classified into different pathologies. – nico Jan 6 '12 at 10:34
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From The History of Cancer

Oldest descriptions of cancer Human beings have had cancer throughout recorded history. So it is no surprise that from the dawn of history people have written about cancer. Some of the earliest evidence of cancer is found among fossilized bone tumors, human mummies in ancient Egypt, and ancient manuscripts. Bone remains of mummies have revealed growths suggestive of the bone cancer, osteosarcoma. Bony skull destruction as seen in cancer of the head and neck has been found, too.

Our oldest description of cancer (although the word cancer was not used) was discovered in Egypt and dates back to about 1600 B.C. It is called the Edwin Smith Papyrus, and is a copy of part of an ancient Egyptian textbook on trauma surgery. It describes 8 cases of tumors or ulcers of the breast that were treated by cauterization, with a tool called the fire drill. The writing says about the disease, "There is no treatment."

As you can see, cancer is not a modern disease.

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There are a number of environmental factors which can influence cancer in man.

Bracken ferns (eaten in the US, Canada and Japaan as Fiddlehead ferns) contains the compound ptaquiloside (PTQ). PTQ is a known carcinogen - and it's responsible for some forms of cancer (gastric) in both animals and humans. Obviously those at greatest risk are those living in areas with a large Bracken fern population, as it does leach to the groundwater and does pass into the milk of cows (which could be a potential exposure route to other populations).

It's also been suggested that PTQ can, in conjunction with other viruses (HPV) be a contributing factor to squamous cell carcinomas in cattle and possibly in humans.

So no, cancer is not a 'man made' disease - there are a number of natural sources of cancer in the environment.

  • Toxic mold contains aflatoxins which are among the most carcinogenic agents known. – Chinmay Kanchi Aug 1 '13 at 7:21
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The American Cancer Society has a long list of known and probable human carcinogens. Among that long list are the following naturally occurring agents (exposure methods are also on the linked site):

  • Beryllium
  • Cadmium
  • Chromium
  • Epstein-Barr virus
  • Ethanol in alcoholic beverages
  • Helicobacter pylori (infection with)
  • Hepatitis B virus (chronic infection with)
  • Hepatitis C virus (chronic infection with)
  • Human papilloma virus (HPV) types 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59 and 66 (Note: The HPV types that have been classified as carcinogenic to humans can differ by an order of magnitude in risk for cervical cancer)
  • Human T-cell lymphotropic virus type I (HTLV-1)
  • Neutrons
  • Radon
  • Schistosoma haematobium (flatworm; infection with)
  • Solar radiation
  • Aflatoxins (naturally occurring mixtures of)
  • Alcoholic beverages
  • Areca nut, Betel nut
  • Coal-tar pitches
  • Coal-tars
  • Mineral oils, untreated and mildly treated
  • Plants containing aristolochic acid
  • Shale-oils
  • Soots
  • Tobacco, smokeless
  • Wood dust

This is only a partial list of the naturally occurring agents and a smaller subset of all known carcinogens.

It can be readily shown that cancers can be caused by natural processes. @Konrad Rudolph has already described that cancer is strongly associated with age--the longer you live, the more likely you are to be exposed to a carcinogen.

Now the caveat: Although there are many naturally occurring carcinogens, there are many more additional carcinogens that exist in sufficient quantities to cause cancer only because of human industrial development. While it is incorrect to say that cancer is a man-made disease, you could claim that human industry has increased the risk-of-exposure to carcinogens, thus advancing the spread, or prevalence, of cancer. To be fair, such a claim should come with evidence showing that the particular carcinogen has caused cancer and that the carcinogen could not exist unless humans created or refined it.

[The last paragraph was edited to hopefully clear up misinterpretations of the more terse version that was originally submitted.]

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    -1 for the undemonstrated comment at the end asserting that there are many more man-made than natural carcinogens. It probably isn't true and you provide no evidence. – matt_black Nov 7 '11 at 13:24
  • @matt_black: You may have misinterpreted my intention. I did not make a comparison between the number of man-made vs. natural carcinogens, I simply pointed out that although there are many naturally occurring carcinogens that are found in sufficient quantities to cause cancer, there are many additional carcinogens that exist in sufficient quantities to cause cancer only because of human actions (creating, refining, or concentrating.) – oosterwal Jul 30 '12 at 21:15
  • The issue is whether man's intervention causes the majority of cancers. That requires evidence and cannot be taken as obvious. – matt_black Jul 30 '12 at 21:50
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    @matt_black You may have well downvoted because you didn't like the avatar. Too often on this site a very useful answer is attacked for a trivial reason. It IS obvious that the mining of asbestos contributed to cancer. The efficient manufacture of cigarettes is pretty obvious. I'm pretty sure the Egyptians didn't have mass production of glues, paints, and gasoline containing benzene. Or do I need to cite a reference? The answer simply claims there are more carcinogens as a result of industry than in ancient times, which should be obvious to any reasonable person. +1 to reverse this injustice. – Randy Jul 5 '13 at 6:01
  • @Randy Nope, I downvoted because the case is simple not proved. Modern standards in industry are (mostly) tight and we don't expose many people to dangerous substances. The Romans, on the other hand, used lead acetate to sweeten wine and their production of lead was so great can be seen in greenland ice cores. So the ancients we not slow to expose their populations to nasties. Are we worse now? I doubt it, and you will have to quote solid evidence to convince me otherwise. – matt_black Jul 5 '13 at 20:42
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Here are the conclusions from the paper (quoted in full):

It is hoped that research in palaeopathology will contribute to the elucidation of the pathogenesis of cancer. The publication of the first histological diagnosis of cancer in an Egyptian mummy is one step along the way. Despite the fact that other explanations, such as inadequate techniques of disease diagnosis, cannot be ruled out, the rarity of malignancies in antiquity is strongly suggested by the available palaeopathological and literary evidence. This might be related to the prevalence of carcinogens in modern societies.

As you can see, the version that got past peer review is full of hedges ("it might be related to", "strongly suggested", "one step along the way"). The press release is just that, a press release, made to get into the news. The science is much murkier.

-5

One thing is certain. In the book "Vaccines, are they really safe and effective?" page 20-21 Says that in 1959 , Bernice Eddy discovered that polio vaccines being administered throughout the world contained an infectious agent capable of causing cancer. SV-40 is what is was. Here is how it works 1. Monkey kidneys are used to develop polio vaccines 2. SV-40 , a cancer causing virus , thrived in monkey kidneys. 3. Polio vaccines were contaminated 4. Millions of people in the USA and throughout the world were infected 5. Cancer rates have increased. SV-40 is found in the brain tumors, bone cancers, lung cancers and leukemia.

Source: National Morbidity Reports taken from the U.S. Public Health surveillance reports. Lancet ( April 18, 1950) pp. 659-63.

Vaccines are one of many sources of cancer. War on cancer is lost, Nixon declared the war on cancer and there is no end in site.

Oh, and we live longer due to 2 proven facts. 1. HVAC (Heating especially ) 2. Modern septic systems

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    a book with an activist agenda, quoting activist groups as its sources, isn't a reliable source of information. – jwenting Jun 7 '11 at 5:59
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    -1 for use of sensationalist agenda in lieu of a properly sourced, and unbiased response. – Darwy Jun 7 '11 at 13:27
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    –1: SV40 does not cause cancer in humans. (1), (2) – Konrad Rudolph Jun 7 '11 at 16:15
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    With enough money to study and do damage control you will certainly find studies they are to your liking. It absolutely does cause cancer. "While the United States government continues to evaluate whether or not SV40 represents a public health threat and whether SV40 is a human carcinogen, several scientists at the NCI concluded that SV40 contributed to the formation of mesotheliomas.[79] In fact, the federal government has licensed technology to target SV40 in the treatment of human mesotheliomas.[80]" sv40foundation.org/CPV-link.html – Tom Stickel Jun 7 '11 at 18:06
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    SV-40 was removed from all polio vaccines in the US by 1963, and a Danish study found no link between SV-40 and cancer rates in Denmark. cancer.gov/cancertopics/factsheet/Risk/sv40 – Darwy Jun 12 '11 at 19:22

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