External
Measured in mSv, over lifetime if more than 100mSv - risk of cancer becomes significant
Most people will not reach, not even nuclear plant workers.
Atomic bomb - exposure of 1Sv ie 1000mSv, about 6-8% of Hiroshima bomb survivors will get cancer, or offspring will get cancer.
Comparing magnitude
Amazing that someone survived a 64 Sv dosage...
Linear No Threshold
The theory is that no matter how small the dosage, there is a risk of cancer.
But unlikely to be true - bcos if true then pilots and stewardess all ganna cancer.
The other spectrum - some radiation is actually good. Since radiation is also used to kill cancer cells. Not too convincing.
Internal
More risky - esp to kids
Measured in Becquerel
Limit in food is 1000 Becquerel per kg
Normal meal in Japan now has 10 B/kg, a lot of meal measurement being done as a result of the heightened fear. The highest meal recorded is still less than 100B/kg
But there are some vege that recorded 27000 B/kg
ie 1 week tour in Japan is unlikely to have any long term impact
Known case from Chernobyl
Kids who drank milk and eat vege (exposed to radioactive iodine) - has a significant chance of getting Thyroid cancer. Kids are vulnerable bcos iodine is trapped in their small thyroid.
This risk should not happen in Fukushima as precautions were taken (kids are given non-radioactive iodine pills)
Unknown unknown
A lot about radiation is not known. Even the iodine case was only known like 10 years after the fact.
The risk is another what if - what if actually a small dose of some other radioactive substance actually causes a great deal of damage in the human body?
However it is safe to say that this risk should be quite remote. We should worry about a lot of other things that have a higher chance of impacting our health - like eating too much fried food, or drinking too much alcohol, or not exercising enough.
Measured in mSv, over lifetime if more than 100mSv - risk of cancer becomes significant
Most people will not reach, not even nuclear plant workers.
Atomic bomb - exposure of 1Sv ie 1000mSv, about 6-8% of Hiroshima bomb survivors will get cancer, or offspring will get cancer.
Comparing magnitude
| 0.098 | μSv: | banana equivalent dose, a whimsical unit of radiation dose[14][note 1] |
| 0.25 | μSv: | U.S. limit on effective dose from a single airport security screening[15] |
| 5 to 10 | μSv: | one set of dental radiographs[16] |
| 80 | μSv: | average dose to people living within 16 km of Three Mile Island accident[17] |
| 0.4 to 0.6 | mSv: | two-view mammogram, using weighting factors updated in 2007[18] |
| 1.5 to 1.7 | mSv: | annual dose for flight attendants[19] |
| 2 to 7 | mSv: | barium fluoroscopy, e.g. Barium meal, up to 2 minutes, 4–24 spot images[20] |
| 10 to 30 | mSv: | single full-body CT scan[21][22] |
| 68 | mSv: | estimated maximum dose to evacuees who lived closest to theFukushima I nuclear accidents[23] |
| 0.67 | Sv: | highest dose received by a worker responding to the Fukushima emergency[24][note 1] |
| 4.5 to 6 | Sv: | fatal acute doses during Goiânia accident |
| 5.1 | Sv: | fatal acute dose to Harry Daghlian in 1945 criticality accident[25] |
| 21 | Sv: | fatal acute dose to Louis Slotin in 1946 criticality accident[26] |
| 64 | Sv: | nonfatal dose to Albert Stevens spread over ~21 years, due to 1945 human experiment[27][note 1 |
Amazing that someone survived a 64 Sv dosage...
Linear No Threshold
The theory is that no matter how small the dosage, there is a risk of cancer.
But unlikely to be true - bcos if true then pilots and stewardess all ganna cancer.
The other spectrum - some radiation is actually good. Since radiation is also used to kill cancer cells. Not too convincing.
Internal
More risky - esp to kids
Measured in Becquerel
Limit in food is 1000 Becquerel per kg
Normal meal in Japan now has 10 B/kg, a lot of meal measurement being done as a result of the heightened fear. The highest meal recorded is still less than 100B/kg
But there are some vege that recorded 27000 B/kg
ie 1 week tour in Japan is unlikely to have any long term impact
Known case from Chernobyl
Kids who drank milk and eat vege (exposed to radioactive iodine) - has a significant chance of getting Thyroid cancer. Kids are vulnerable bcos iodine is trapped in their small thyroid.
This risk should not happen in Fukushima as precautions were taken (kids are given non-radioactive iodine pills)
Unknown unknown
A lot about radiation is not known. Even the iodine case was only known like 10 years after the fact.
The risk is another what if - what if actually a small dose of some other radioactive substance actually causes a great deal of damage in the human body?
However it is safe to say that this risk should be quite remote. We should worry about a lot of other things that have a higher chance of impacting our health - like eating too much fried food, or drinking too much alcohol, or not exercising enough.
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