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Do you smoke tobacco, or Polonium 210 ??

Discussion in 'General Board' started by domaingenius, Nov 29, 2006.

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  1. domaingenius

    domaingenius Well-Known Member

    Dec 2004
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    Off topic but it is scary to see that Cigarettes contain Polonium 210 exactly the same stuff that killed that Russian guy recently. This part 1 of 2 as too many chars otherwise;

    [Radiologic Technology]
    Cancer risk in relation to radioactivity in tobacco.

    Leaf tobacco contains minute amounts of lead 210 (210Pb) and polonium
    210 (210Po) both of which are radioactive carcinogens and both of
    which can be found in smoke from burning tobacco. Tobacco smoke also
    contains carcinogens that are nonradioactive.

    People who inhale tobacco smoke are exposed to higher concentrations of
    radioactivity than nonsmokers. Deposits of 210Pb and alpha
    particle-emitting 210Po form in the lungs of smokers, generating
    localized radiation doses for greater than the radiation exposures humans
    experience from natural sources. This radiation exposure, delivered 'to'
    sensitive tissues for long periods of time, may induce cancer both alone
    and synergistically with nonradioactive carcinogens.

    This article explores the relationship between the radioactive and
    nonradioactive carcinogens in leaf tobacco and tobacco smoke and the risk
    of cancer in those who inhale tobacco smoke.

    Almost all externally-induced cancer in humans is reported to be caused by
    cigarette smoking, alcohol and some foods.[1] In the 1960s it was reported
    that leaf tobacco and tobacco smoke contained radioactivity,[2-6] and it
    was noted that people who inhale tobacco smoke retain smoke-borne
    radioisotopes in their lungs.[2,4,6]

    Leaf tobacco contains minute quantities of radioactive isotopes that pose a
    radiation exposure hazard to those who intentionally or passively inhale
    tobacco smoke. This article reviews scientific literature documenting
    radioactivity in leaf tobacco, radioactivity in tobacco smoke, the
    concentrations of radioactivity on and within the tissues of those who
    inhale tobacco smoke, the radiation doses to organs and tissues, and the
    significance of these exposures toward cancer initiation in those who
    inhale the smoke. Because synergistic effects toward cancer initiation
    exist between smoke-borne radioactivity and inhaled nonradioactive
    carcinogens, the article also discusses some of the nonradioactive
    carcinogens in tobacco.


    Identification of 210Pb and 210Po

    In Tobacco Smoke and in Smokers

    In the 1960s, investigators reported that lead 210 (210Pb) and
    polonium 210 (210Po) are present in both gaseous and particulate
    phases of tobacco smoke.[2-4] Both radioisotopes descend from radium 226
    and its decay product, radon 222. Lead 210 decays by beta particle emission
    to bismuth 210, which then decays by beta particle emission to 210Po.
    Polonium 210 emits high energy alpha particles (5.3 million eV) and gamma
    radiation (550,000 eV) when it decays, becoming stable lead 206.[7,8]

    Tar in tobacco smoke traps 210Po on lung epithelium, particularly at
    the bifurcations of peripheral bronchioles, leading to very significant
    localized radiation doses.[2,4] It also was reported[2] that as low as 36
    rem exposure to bronchial epithelium of a smoker during 25 years of smoking
    is significant to the induction of lung cancer due to the coincidental
    presence of nonradioactive carcinogens in the smoke.

    Some investigators[4] believe the quantities of nonradioactive carcinogens
    in tobacco smoke are too small, by themselves, to generate the lung cancer
    rates caused by smoking. Supporting this belief, it has been shown[2,5]
    that the urine of smokers contains about six times more 210Po than
    the urine of nonsmokers, and that the rate of bladder cancer among smokers
    increases in relationship to how much they smoke. Nonradioactive
    carcinogens in tobacco tar are not found in the urine of smokers, no matter
    how heavily they smoke.[5]

    210Pb and 210Po in Leaf Tobacco

    The amount of 210Pb and 210Po radioactivity in leaf tobacco is
    minute per gram of tobacco. This low concentration of radioisotopes,
    however, can accumulate into significant concentrations in and on the
    tissues of those who inhale the smoke from burning tobacco.

    Tobacco plants absorb 210Pb and 210Po from the soils in which
    they grow.[9-13] In addition, tobacco plants gather naturally present radon
    222 descendants from the surrounding air.[14,15] Tobacco leaves have sticky
    trichomes, or "hairs," on both sides.[9,14] Radon daughter products collect
    on aerosols in the atmosphere which, in turn, are captured on the sticky
    surfaces of the trichomes. This provides an additional concentration of
    210Pb on leaf surfaces beyond its concentration within the whole
    leaf.[14] It has been shown[16] that tobacco leaf trichomes capture
    atmospheric aerosols, polymerize with them in the heat of burning tobacco
    and are present in that form in cigarette smoke.

    The 210Po content of tobacco from several countries has been
    measured. One report[17] on the radioactivity of tobacco grown in India
    indicated that a single Indian-grown tobacco cigarette had a 210Po
    complement of up to 0.4 pCi. Another group from India[13] found a great
    difference between the 210Po content of Indian-grown tobacco and
    tobacco from the United States. The 210Po in Indian tobacco averaged
    0.09 pCi per gram, whereas the 210Po in tobacco grown in the United
    States averaged 0.516 pCi per gram--about 5 1/2 times as much

    Although such sizable differences in radioactivity concentration in leaf
    tobacco may be related to variations in natural fallout, natural soil
  2. Domain Forum

    Acorn Domains Elite Member

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  3. domaingenius

    domaingenius Well-Known Member

    Dec 2004
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    Part 2 of 2

    radioactivity or absorption differences due to soil pH, another factor may
    be responsible. It has been noted[9,19] that modern tobacco farming takes
    advantage of special fertilization methods, and that tobacco leaf grown in
    soil with low nitrogen levels is "more flavorful" than tobacco leaf grown
    in soils high in nitrogen.

    To grow this quality of tobacco, farmers in "developed" countries such as
    the United States usually fertilize their tobacco fields with chemically
    manufactured fertilizer high in phosphate content. Tobacco farmers in
    poorer countries do not. The phosphate portion of this fertilizer is made
    from a rock mineral, apatite, that is ground to powder, dissolved in acid
    and further processed (personal communication, Mobil Mining and Minerals,
    Houston, Texas, 1995). Apatite rock contains radium and its many descendant
    radioisotopes, including both radioactive lead and polonium.(210Po)
    When this type of fertilizer is spread onto tobacco fields year after year,
    soil nitrogen is depleted, providing a "more flavorful" smoking tobacco.
    The higher the phosphate level of the fertilizer used, the higher the
    concentration of 210Pb and 210Po in the tobacco leaves.[19]

    A measurement of the 210Po content of mainstream cigarette smoke from
    U.S.-grown tobacco is reported to be 0.0263 pCi per cigarette;[20] which is
    about 0.1 pCi per milligram of smoke. Other investigators[14] have measured
    the 210Po concentration in the mainstream tobacco smoke of one
    cigarette as approximately 0.036 pCi, with a corresponding measurement of
    0.81 pCi of 210Pb per gram of dry condensate derived from the whole

    The filtration of mainstream tobacco smoke by ordinary commercial cigarette
    filters has a negligible effect on the concentration of radioactivity in
    the smoke inhaled into the lungs of smokers.[2,6,19,20] It has been
    estimated that the intake of 210Po by a typical smoker is about 0.72
    pCi per pack of 20 cigarettes.[21] In another study,[14] it was noted that
    210Pb specific activities of 100 pCi per milligram of pyrolized
    glandular heads of tobacco leaf trichomes in tobacco smoke often are
    reached or exceeded.

    It also has been reported[14] that radioactive lead and polonium are
    adsorbed onto tobacco smoke particles vented into room air from burning
    tobacco, where they remain suspended and available until inhaled as
    "secondhand" smoke by anyone present in the room.

    Concentrations of 210Pb and 210Po

    In the Bodies of Those Who Inhale Tobacco Smoke

    Compared to nonsmokers, heavy smokers essentially have four times greater
    radioisotope density throughout their lungs.[21] It has been estimated[22]
    that the 210Po content of blood in smokers averages 1.72 pCi per
    kilogram and, in nonsmokers, 0.76 pCi per kilogram. Concentrations of
    210Pb and 210Po in rib bones and alveolar lung tissue were
    found to be twice as high in ax-smokers as in nonsmokers, even a year after
    cessation of smoking.[21]

    In smokers, the concentration of 210Po directly on epithelial tissue
    at segmental bifurcations of bronchioles is two orders of magnitude greater
    (i.e., 100 times greater) than is its concentration overall within their
    lungs,[23] which already is four times higher in heavy smokers than it is
    in nonsmokers.[21] Other investigators[24] found that the lungs, blood and
    livers of smokers contained significantly more 210Po than did those
    of nonsmokers.

    Dosage from the Radioactivity

    From Inhaled Tobacco Smoke

    Polonium 210 emits alpha particles upon its decay. Alpha particles have
    penetrations limited to about 40 microns or less in animal tissue,[8,25,26]
    the aggregate diameter of only several typical cells. Alpha particle
    radiation has a very destructive effect on animal tissue because virtually
    all of its very high ionizing energy is expended within the tissue. Due to
    its double positive charge, limited range in tissue and enormously high
    energy, an alpha particle can produce huge numbers of ion pairs in
    substances with which it interacts. For example, 20,000 ion pairs can be
    produced per alpha particle per centimeter path length in air.[8] DNA
    chromosome damage by alpha particle radiation is much greater, by 100
    times, than by exposure of DNA to other types of radiation.[19]

    The radiation dose from 210Po alpha particle radiation has been
    measured as 82.5 millirads per day for heavy smokers.[27] Extrapolating
    this measurement, doses of 30.1 rads per year and 752.5 rads per 25 years
    of smoking two packs of cigarettes per day are calculated. Such a radiation
    exposure dose rate is about 150 times higher than the approximately 5
    rem([dagger]) per 25 years received from natural background radiation
    sources.[2] Interestingly, many of the lung cancers contracted by cigarette
    smokers are adenocarcinomas, a type of lung cancer that can be caused by
    alpha particle radiation from 210Po.[19]

    In localized areas of tissue that surround deposits of insoluble
    210Pb particles, the dose rate from 210Po alpha particle
    radiation can be from 100 to 10,000 times that of natural background
    radiation sources.[19] The "low-polonium" tobacco grown in India provides
    its users with a lung burden of about 24 millirads a day[13]--or 219 rads
    during 25 years of smoking. This is about 40 times the exposure rate from
    natural background radiation inhaled from the earth's atmosphere.[2] Other
    researchers[2,4,14,26,28] have estimated that a range of dose rates from
    210Po alpha particle exposure of lung epithelial tissue in smokers is
    from 165 rem to 1000 rem over a period of 25 years.

    Carcinogenicity of Low Dose Rate Radiation Exposure

    Those who directly inhale tobacco smoke receive alpha particle bombardment
    totalling many rads over many years of smoking.[14,23,27,28] The frequency
    of harmful effects from low dose rate radiation exposure is proportional to
    the total dose received over time.[29] The risk of cancer initiation for
    any cumulative radiation dose increases significantly at lower dose rates
    in accordance with the lengthening of exposure periods[14] such as those
    experienced by smokers. Investigators have shown that inhalation of tobacco
    smoke causes more DNA damage in smokers than in nonsmokers.[30] DNA damage
    is reported to be associated with cancer initiation.[19]

    Lung cancer has been induced in test animals using less than one-fifth the
    210Po exposure experienced by a two-pack-a-day smoker during 25 years
    of smoking.[31] It has been suggested[19,32] that 210Po accounts for
    many, if not all, cigarette smoke-induced lung cancers.

    Polonium 210 is a "bone seeker." In other words, bone tissue avidly takes
    up available 210Po.[8] Ionizing radiation delivered to bone marrow at
    relatively low rates (e.g., 7 rads to 13 rads total exposure) has been
    reported[33] to induce the onset of leukemia at relatively high rates per
    red of exposure.

    Despite this evidence, there has been doubt concerning the role of
    radioactivity in general and 210Po, specifically, as prime cancer
    initiators in those who inhale tobacco smoke.[26,34] Because polonium is
    water soluble, could it linger in the lungs long enough to cause cancer?

    It might ordinarily be thought that inhaled 210Pb particles and
    210Po would be readily cleared from the lungs by ciliary action or be
    otherwise excreted, even though tobacco smoke inhalation results in
    decreased ciliary activity in the bronchioles.[35,36] However, a continuing
    alpha particle bombardment from 210Po is caused by pockets, or
    concentrations, of insoluble 210Pb and polymerized tobacco leaf
    trichome-210Pb entities because the 210Pb decays to become
    210Pb[7,8] in or on the affected tissue.[14,15,19] Another impediment
    to clearance of 210Po from the lungs of those who inhale tobacco
    smoke is the "locking down" of the radioisotope by tobacco tar present in
    the smoke.[2,4,23,26,32]

    Much of the experimental work performed to assess the carcinogenicity of
    tobacco smoke has been done using mouse skin assays in which tobacco smoke
    distillates are placed onto shaved areas of mouse skin to look for
    development of cancer.[34] However, because of the unique mechanics of
    210Pb and 210Po deposition in the lungs, mouse skin assays are
    inadequate for assessing the role of those radioisotopes in lung cancer

    Synergistic Effects from Tobacco Smoke
  4. Pred United Kingdom

    Pred Well-Known Member

    Jul 2006
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    Quite indepth then? LOL
    I smoked for best part of 20 years. Gave up in April. Haven't looked back.
    No tablets, patches etc.
    It is one of the hardest things to kick, doubt. I kept trying to give up, every day, LOL
    If you keep trying & really want to you can.
    The only thing in back of my mind is about 10 years ago gave up for a year, then started again on holiday, what a twat!
    Guess we must be like alcoholics, one day at a time! :mrgreen:
  5. olebean

    olebean Well-Known Member

    Nov 2005
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    Ive never smoked

    my body is a temple :cool: stuffed full of riches (usually food and wine)
  6. accelerator United Kingdom

    accelerator Well-Known Member

    Apr 2005
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