3 ms·

Is radioactive iodine the only radioactive isotope we'd expect to be exposed to.at lethal doses?

lmilcin 7y ago
No. Caesium 137 is probably the worst offender, but there is not much you can do as an individual other than to stay away from contact with it. Also, this is not about lethal doses. There is typically very small area in immediate vicinity of the explosion that is directly lethal (like, LD50 lethal). Most of the effect on large area is through increased radiation and through radioactive elements getting concentrated in food chain and in various tissues of your body. You might never know if the radiation from the event was what is killing you but this can be measured statistically to say "over X years there is Y deaths additional to what could be expected that could be attributed to increased radiation".
AlphaGeekZulu 7y ago
All kinds of radioactive isotopes might enter or attach to your body in many ways as consequence of a nuclear accident. Any radioactive particle that gets close to or into your body will cause some damage depending on the type (alpha, beta, gamma), strength of radiation and duration of exposure. If you are not exposed to an immediately lethal dose, the damage in the body is a statistical thing. The longer and the more intense the radioactive particles remain on or in your body, the more likely is the chance for a serious health issue. The strategy is to remove radioactive particles as fast as possible to minimize the probability of damage. Radioactive particles on your skin can be washed away. (This is not so fun as the every-day shower). Radioactive particles that you inhaled are a really bad thing, I do not know how to deal with radioactive particles in the lungs (except wearing filter masks in time). Particles that entered the body with food will be excreted within a couple of hours. But: your body has an organ - the thyroid gland - which collects iodine from your food and stores it long time. A radioactive form of iodine - iodine 131 - is a common byproduct of nuclear contamination. If this gets stored in your body, it remains long enough to dramatically raise the chance of cancer. Therefore you fill your thyroid gland with non-radioactive iodine, hopefully BEFORE your body gets contaminated with radioactive iodine. So the special thing with iodine 131 is, that it is common, that the body does not make a difference to nonradioactive iodine and there is an organ that stores it. By taking iodine pills, you only improve probabilities on that one factor! There are plenty other ways to take damage from radioactive accidents.
- jfengel 7y ago
  Has this actually been tried? I know there's no way to do a proper controlled test, at least in humans ("OK,you take this pill, and you take this placebo. Now, here, breathe this."), but is there any naturally-occurring data that might imply that this actually works? Say, distributing pills in a place with a natural radioactive iodine source, or counting up thyroid cancers after Chernobyl and comparing people-who-took-pills to people who didn't? I assume there is at least a rat study.
- ethbro 7y ago
  https://www.who.int/ionizing_radiation/pub_meet/tech_briefings/potassium_iodide/en/ https://www.who.int/ionizing_radiation/pub_meet/tech_briefin... Tl;dr: "Commonly known as thyroid blocking, taking potassium iodide (KI)1 before or at the beginning of exposure to radioactive iodine blocks the uptake of radioactive iodine by the thyroid gland, thus reducing exposure of the thyroid to internal radiation. KI does not protect against any other radioactive substances, e.g. radioactive caesium. It is not a generic radiation antidote." "Taking KI shortly before or immediately at the time of exposure to radioactive iodine offers the most effective protection. [...] If taken 4 hours after exposure, protection will be reduced by half; taking KI more than 24 hours after exposure will offer no protection." "A single dose of KI is usually sufficient for adequate protection for 24 hours." "Age group - Mass of KI (mg) - Example of fraction of tablets (130 mg KI tablets) >12 years and adults - 130mg - 1 3 – 12 years - 65mg - 1/2 1 month – 3 years - 32mg - 1/4 Neonate (< 1) - 16mg - 1/8" "The risk of thyroid cancer in children following exposure to radioactive iodine is higher than in adults; younger age groups are at highest risk. As a result, the protection of children must be considered a priority" "During pregnancy, the mother's thyroid gland is metabolically more active than in non-pregnant women, and the amount of radioactive iodine that will be taken up by the thyroid increases in comparison with other adults. The foetal thyroid gland may be exposed to radioactive iodine through the placenta, but will also be protected by the KI taken by the mother. [...] The amount of KI that a breastfeeding woman will provide to an infant through breast milk is not enough to protect the thyroid of an infant exposed to radioactive iodine." "The risk of side effects from KI increases with age, while the risk of radiation-induced thyroid cancer in individuals over 40-years old is low. For this reason, thyroid blocking with KI is not generally indicated in adults over 40 years of age, unless the projected radiation dose to the thyroid rises to levels that threaten the thyroid gland and interfere with its function." "Adverse effects of KI on thyroid function are more frequent in individuals with other, pre-existing thyroid disorders. These disorders are more common in older adults and in the elderly than in children or young adults."
your-nanny 7y ago
Thank you everyone for giving very informative and serious replies to my question.

No. Caesium 137 is probably the worst offender, but there is not much you can do as an individual other than to stay away from contact with it. Also, this is not about lethal doses. There is typically very small area in immediate vicinity of the explosion that is directly lethal (like, LD50 lethal). Most of the effect on large area is through increased radiation and through radioactive elements getting concentrated in food chain and in various tissues of your body. You might never know if the radiation from the event was what is killing you but this can be measured statistically to say "over X years there is Y deaths additional to what could be expected that could be attributed to increased radiation".

AlphaGeekZulu 7y ago

All kinds of radioactive isotopes might enter or attach to your body in many ways as consequence of a nuclear accident. Any radioactive particle that gets close to or into your body will cause some damage depending on the type (alpha, beta, gamma), strength of radiation and duration of exposure. If you are not exposed to an immediately lethal dose, the damage in the body is a statistical thing. The longer and the more intense the radioactive particles remain on or in your body, the more likely is the chance for a serious health issue. The strategy is to remove radioactive particles as fast as possible to minimize the probability of damage. Radioactive particles on your skin can be washed away. (This is not so fun as the every-day shower). Radioactive particles that you inhaled are a really bad thing, I do not know how to deal with radioactive particles in the lungs (except wearing filter masks in time). Particles that entered the body with food will be excreted within a couple of hours. But: your body has an organ - the thyroid gland - which collects iodine from your food and stores it long time. A radioactive form of iodine - iodine 131 - is a common byproduct of nuclear contamination. If this gets stored in your body, it remains long enough to dramatically raise the chance of cancer. Therefore you fill your thyroid gland with non-radioactive iodine, hopefully BEFORE your body gets contaminated with radioactive iodine. So the special thing with iodine 131 is, that it is common, that the body does not make a difference to nonradioactive iodine and there is an organ that stores it. By taking iodine pills, you only improve probabilities on that one factor! There are plenty other ways to take damage from radioactive accidents.

jfengel 7y ago
Has this actually been tried? I know there's no way to do a proper controlled test, at least in humans ("OK,you take this pill, and you take this placebo. Now, here, breathe this."), but is there any naturally-occurring data that might imply that this actually works? Say, distributing pills in a place with a natural radioactive iodine source, or counting up thyroid cancers after Chernobyl and comparing people-who-took-pills to people who didn't? I assume there is at least a rat study.
ethbro 7y ago
https://www.who.int/ionizing_radiation/pub_meet/tech_briefings/potassium_iodide/en/ https://www.who.int/ionizing_radiation/pub_meet/tech_briefin... Tl;dr: "Commonly known as thyroid blocking, taking potassium iodide (KI)1 before or at the beginning of exposure to radioactive iodine blocks the uptake of radioactive iodine by the thyroid gland, thus reducing exposure of the thyroid to internal radiation. KI does not protect against any other radioactive substances, e.g. radioactive caesium. It is not a generic radiation antidote." "Taking KI shortly before or immediately at the time of exposure to radioactive iodine offers the most effective protection. [...] If taken 4 hours after exposure, protection will be reduced by half; taking KI more than 24 hours after exposure will offer no protection." "A single dose of KI is usually sufficient for adequate protection for 24 hours." "Age group - Mass of KI (mg) - Example of fraction of tablets (130 mg KI tablets) >12 years and adults - 130mg - 1 3 – 12 years - 65mg - 1/2 1 month – 3 years - 32mg - 1/4 Neonate (< 1) - 16mg - 1/8" "The risk of thyroid cancer in children following exposure to radioactive iodine is higher than in adults; younger age groups are at highest risk. As a result, the protection of children must be considered a priority" "During pregnancy, the mother's thyroid gland is metabolically more active than in non-pregnant women, and the amount of radioactive iodine that will be taken up by the thyroid increases in comparison with other adults. The foetal thyroid gland may be exposed to radioactive iodine through the placenta, but will also be protected by the KI taken by the mother. [...] The amount of KI that a breastfeeding woman will provide to an infant through breast milk is not enough to protect the thyroid of an infant exposed to radioactive iodine." "The risk of side effects from KI increases with age, while the risk of radiation-induced thyroid cancer in individuals over 40-years old is low. For this reason, thyroid blocking with KI is not generally indicated in adults over 40 years of age, unless the projected radiation dose to the thyroid rises to levels that threaten the thyroid gland and interfere with its function." "Adverse effects of KI on thyroid function are more frequent in individuals with other, pre-existing thyroid disorders. These disorders are more common in older adults and in the elderly than in children or young adults."

your-nanny 7y ago

Thank you everyone for giving very informative and serious replies to my question.