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Medical Dangers of radioactivity

  1. Jul 29, 2011 #1
    Not sure if this is the right forum, please move if a more appropriate forum exists.

    Even after Fukoshina I'm not quite sure what to make of radioactivity, how to read levels or radiation and what the danger is of getting sick.

    Below are two small articles about the Aktau area in western Kazakhstan. Lake Koshkar Ata seems to be contaminated with heavy minerals and radioactive waste, there's an open cast uranium mine nearby and lots of scrap metal, originally used for mining.

    http://www.grida.no/publications/vg/caspian/page/1356.aspx" [Broken]
    http://www.worldlakes.org/shownews.asp?newsid=1640" [Broken]

    From the articles, or just from comon sense, what is your feeling about living there? This is not a school topic. The Aktau area is currently seeing a boom from the oil industry, with many Western companies and people moving there. There even seem to be plans to build a Dubai-like town with artificial islands, etc.. I just don't find any information on how dangerous it actually is to live there. In case you ask: there are some amazing job offers out there :surprised
    Last edited by a moderator: May 5, 2017
  2. jcsd
  3. Jul 29, 2011 #2


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    This chart is quite useful for understanding the effects of different levels of radiation.

    I'm pressed for time right now and don't have any knowledge of the specific area but if you can find readings for the radiation levels there you can compare it to the chart to get an understanding.
  4. Jul 29, 2011 #3
    The main problem in determining risk is that it not only depends on dose but on dose rate, type of exposure (acute or chronic), the age of the individual, and the overall health of the individual.

    I can't remember the source, but I had read that a chronic dose of 1000mrem increases the risk of fatal cancer by 1 in 2000. Since you have a (rough) chance of developing fatal cancer of 1 in 3 to 1 in 4 (studies vary), this is a relatively insignificant increase in risk. But, make that same dose acute, and the risk is increased (the study didn't give the number, though).
  5. Jul 29, 2011 #4
    daveb's statistic of a risk/dose of 0.05 per Sv is in the ballpark of published literature. If you want to read more about risk estimates the following resources might be useful:

    UNSCEAR (2000): Sources and Effects of Ionizing Radiation, Vol. II: Effects
    ICRP 60 (1990): Recommendations of the International Commission on Radiological Protection
    NCRP 116 (1993): Limitation of Exposure to Ionizing Radiation
    BEIR V (1990): Health Effects of Exposure to Low Levels of Ionizing Radiation

    An interesting topic is radiation hormesis, in which small amounts of radiation might actually reduce cancer incidence and mortality. There have been studies on people who live in areas where background radiation is several times the norm (background is roughly 3.5 mSv per year) where they found cancer incidence rates are slightly decreased, if changed at all.

    See Calabrese et. al in Nature 2003 "Toxicology rethinks its central belief" if you're interested.
  6. Jul 30, 2011 #5
    Thanks a lot for all your answers. I just looked through the two articles linked above again. one of them mentions:
    "Analyses of air and soil samples showed that contamination caused by Koshkar-Ata is below the average world level (1.15 - 0.20 Roentgen). Meanwhile, a real danger is being posed by the burial places of radioactive wastes at the mouth of the Koshkar-Ata. Radiation activity in these burial places reaches 5,000 microroentgen per hour."

    Well, the second number sounds very high to me. However, it doesn't say what the range of radiation is. Does radiation spread by wind or does it kind of stay at a fixed point? The first number doesn't give a time. 1.15 - 0.20 Roentgen per year or per hour? Per our would probably be quite a lot...
    When I look at the link provided with the first answer I see that 50ms is the maximum yearly dose permitted by us radiation workers and 100ms is the minimum dose linked to increased cancer risk. If I convert the roentgen correctly, then that doesn't look too good, doesn't it?

    "Among the industrial dumps and derelict industrial equipment there are several radiation hotspots exceeding 1,500 to 3,000 µR/h, as against natural radiation in Kazakhstan of 10 to 15 µR/h."

    If I do conversions correctly then the yearly natural radiation in kz is already much higher than what seems to be the upper limit of what's recommended, right?

    From Wikipedia "his high level of radiation does not seem to have caused ill effects on the residents of the area and even possibly has made them slightly more radioresistant, which is puzzling and has been called "radiation paradox". It has also been reported that residents have healthier and longer lives"
    Right, but that would probably be for people who live there all their live?

    So basically, I've seen a lot of numbers, but they are still just numbers to me. I don't really know much more :(
  7. Aug 1, 2011 #6
    kinda crazy isn't it... The NCRP report 116 is a good guide, in the ncrp report #49 it says that the safe yearly dose is 100 mrem or 1 mSv a year for public exposure above normal back ground radiation. The dose in any unrestricted area in the environment from external sources does not exceed 0.002 rem (0.02 mSv) in any one hour.

    Having a breakdown chart to hourly,daily,weekly dose rates listing different radionuclide's would be an easy fix but i'm sure it would freak many people out.

    here is a calculator that should give you some basic ideas on dose rates:


    here's a Dose convert calculator too:

    Last edited: Aug 1, 2011
  8. Jul 25, 2012 #7
    I don't know if you found any information yet. But I would recommend to stay away from that place. I was born in Aktau and at the age of 3, I was diagnosed with kidney cancer. Nobody in my family has a history of this desease. I have nothing to blame but this lake and the whole environment of the region. I don't really believe in the radiation paradox because now both my parents deal with some type of tumor. They lived in Aktau their whole life and yet hardly resistant to radiation. My advice is stay away from that place and look for job in a safer place, may be in other part of Kazakhstan.
  9. Jul 26, 2012 #8
    Here's a good Q&A link http://hps.org/publicinformation/ate/cat25.html

    Statistics are usually "population" statistics, e.g. "X" cancers per 100,000 people per 1 rem and they aren't appropriate for determining an individual's risk. Those of us that have worked in nuclear power plants, national labs, medicine, etc. are able to work safely around radiation.
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