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We know this must be a statistical artefact because of the way cancer arises in humans when they are exposed to a carcinogens. Take tobacco smoke for example, i

We know this must be a statistical artefact because of the way cancer arises in humans when they are exposed to a carcinogens. Take tobacco smoke for example, it does not cause just one type of cancer to rise in frequency (say lung cancer), but a whole range of cancers [0]. You just can’t expose people to a general carcinogen like “pollution” and end up with one kind of rare cancer. Cancer just doesn’t work this way. 0. https://en.wikipedia.org/wiki/Health_effects_of_tobacco https://en.wikipedia.org/wiki/Health_effects_of_tobacco

nkurz 8y ago
What I think you mean to say is that if these cancers were caused by environmental contamination, we would expect to see elevated levels of other cancers as well. First, I'm not sure this is true for all forms of cancer and all types of carcinogens. While it's true that tobacco smoke contains a wide variety of carcinogens and causes a wide variety of cancers, it doesn't seem impossible that some particular chemical might cause an increase in rhabdomyosarcomas without producing a general increase. For example, I don't think that asbestos exposure leads to an across the board increase in all cancers, just an increase in lung cancer and mesothelioma. What makes you so sure that there cannot exist a more focused carcinogen that causes just rhabdomyosarcoma? Second, you seem to be assuming that just because the article focuses on one particular type of cancer, that the town does not have elevated levels of other cancers. Do you have outside evidence that makes you so sure of this that you conclude that the increased rate of once type of cancer "must be a statistical artifact" rather than evidence of a greater underlying problem that merits further research?
- danieltillett 8y ago
  I not only mean to say that, it is what I said. Yes it is possible for some specific rare cancers to have some single specific cause (mesothelioma and asbestos are probably the best known example), but this is not what is seen with nearly all other carcinogens. The reason is two fold: 1) Almost all carcinogens are not localised to a precise body location (asbestos is a rare example). Once inside a person the carcinogen is distributed everywhere. This is why exposure to tobacco smoke for example gives rise to cancers in distant locations to the lung. 2) Carcinogenic pollutants are almost never just a single chemical, but a wide range of compounds. Cancer is not like infectious disease where you have one causative agent that gives rise to a distinct set of symptoms. The nature by which cancer arise (loss of cellular replication control), by its very nature rarely proceeds down the same path - expose one person to a specific carcinogen and they might get liver cancer and lung cancer in a different person.
  - nkurz 8y ago
    Thanks. So you think that apart from very special cases like asbestos, any chemical cause would cause other cancers as well, and there is no reasonable chance that a particular chemical could cause only rhabdomyosarcoma. I'll defer to your expertise here. I was partly confused by one of the links from the article[1], which says "These cancers are derived from similar cellular lineage; therefore, these sarcomas are closely related in cellular composition. It is biologically plausible that a common exposure exists." Is there a way in which this might make sense? Are they suggesting that it might be biologically contagious rather than chemically induced? And the second question? When you conclude that the prevalence of this particular must be a statistical artifact rather than a reproducible effect, do you have reason to believe that there are not elevated levels of other cancers in the area? Or is this not actually necessary to show? [1] https://www.facebook.com/notes/jason-c-spencer/response-to-waycross-journal-herald-opinion-piece-tv-news-report-wrong/10153989158988685/ https://www.facebook.com/notes/jason-c-spencer/response-to-w...
    - danieltillett 8y ago
      I don't think it is biologically plausible at all that a common chemical exposure exists. It is possible, just unlikely. It also doesn't match up with what we know about pollutant chemicals being a wide range of compounds, nor the broad range of cancers seen with other known pollutant chemicals. I would be far more likely to believe that a large number of unrelated cancers in an area were caused by pollutant carcinogens, than a small number of rare cancers. I don't know if there is an elevated rate of cancer in this area, but I assume not since it would be the first thing that anyone looking at this rare cancer cluster would look for.

nkurz 8y ago

What I think you mean to say is that if these cancers were caused by environmental contamination, we would expect to see elevated levels of other cancers as well. First, I'm not sure this is true for all forms of cancer and all types of carcinogens. While it's true that tobacco smoke contains a wide variety of carcinogens and causes a wide variety of cancers, it doesn't seem impossible that some particular chemical might cause an increase in rhabdomyosarcomas without producing a general increase. For example, I don't think that asbestos exposure leads to an across the board increase in all cancers, just an increase in lung cancer and mesothelioma. What makes you so sure that there cannot exist a more focused carcinogen that causes just rhabdomyosarcoma? Second, you seem to be assuming that just because the article focuses on one particular type of cancer, that the town does not have elevated levels of other cancers. Do you have outside evidence that makes you so sure of this that you conclude that the increased rate of once type of cancer "must be a statistical artifact" rather than evidence of a greater underlying problem that merits further research?

danieltillett 8y ago
I not only mean to say that, it is what I said. Yes it is possible for some specific rare cancers to have some single specific cause (mesothelioma and asbestos are probably the best known example), but this is not what is seen with nearly all other carcinogens. The reason is two fold: 1) Almost all carcinogens are not localised to a precise body location (asbestos is a rare example). Once inside a person the carcinogen is distributed everywhere. This is why exposure to tobacco smoke for example gives rise to cancers in distant locations to the lung. 2) Carcinogenic pollutants are almost never just a single chemical, but a wide range of compounds. Cancer is not like infectious disease where you have one causative agent that gives rise to a distinct set of symptoms. The nature by which cancer arise (loss of cellular replication control), by its very nature rarely proceeds down the same path - expose one person to a specific carcinogen and they might get liver cancer and lung cancer in a different person.
- nkurz 8y ago
  Thanks. So you think that apart from very special cases like asbestos, any chemical cause would cause other cancers as well, and there is no reasonable chance that a particular chemical could cause only rhabdomyosarcoma. I'll defer to your expertise here. I was partly confused by one of the links from the article[1], which says "These cancers are derived from similar cellular lineage; therefore, these sarcomas are closely related in cellular composition. It is biologically plausible that a common exposure exists." Is there a way in which this might make sense? Are they suggesting that it might be biologically contagious rather than chemically induced? And the second question? When you conclude that the prevalence of this particular must be a statistical artifact rather than a reproducible effect, do you have reason to believe that there are not elevated levels of other cancers in the area? Or is this not actually necessary to show? [1] https://www.facebook.com/notes/jason-c-spencer/response-to-waycross-journal-herald-opinion-piece-tv-news-report-wrong/10153989158988685/ https://www.facebook.com/notes/jason-c-spencer/response-to-w...
  - danieltillett 8y ago
    I don't think it is biologically plausible at all that a common chemical exposure exists. It is possible, just unlikely. It also doesn't match up with what we know about pollutant chemicals being a wide range of compounds, nor the broad range of cancers seen with other known pollutant chemicals. I would be far more likely to believe that a large number of unrelated cancers in an area were caused by pollutant carcinogens, than a small number of rare cancers. I don't know if there is an elevated rate of cancer in this area, but I assume not since it would be the first thing that anyone looking at this rare cancer cluster would look for.