Death toll from radiation exposure wrt. Chernobyl?

[Rive]

the WHO estimates 9000.

...the four most exposed populations considered here, predictions currently available are of the order of 9000 to 10 000 deaths from cancers and leukaemia over life.

The difference is more or less due the population size and some minor variables related to the application of LNT.
Some scientists tends to take the lack of statistical evidence as a freedom to guess.

 

[mfb]

The only certain number is 50.
Everything higher than that is a more or less educated guess based on models known to be conservative (=they probably overestimate the actual number of cases).

 

[Laroxe]

This all seems to focus on exposure to high energy, short wave, gamma radiation exposure. In nuclear accidents this is rarely the main concern, it is the release various radio isotopes into the environment which can then be absorbed. Radioactive isotopes of minerals behave in the same way as non radioactive isotope's and our body uses them in the same way. The increase in thyroid cancers will largely be due to the release of radio-iodine into the environment which is rapidly incorporated into the food chain, virtually all the iodine we take in is concentrated in the thyroid, which in the case of radio-iodine then continues to emit lower energy particles damaging the thyroid tissue.
Most risk has to take into account the isotopes released, how people are exposed, the radioactive half life of the element and the usual biology of the elements involved.

 

[mfb]

This all seems to focus on exposure to high energy, short wave, gamma radiation exposure.

Gamma rays from incorporated iodine is an example of this exposure (although the beta decays are more important here). The thread has discussed the whole dose all the time, your post is misleading.

 

[Laroxe]

Gamma rays from incorporated iodine is an example of this exposure (although the beta decays are more important here). The thread has discussed the whole dose all the time, your post is misleading.

The post was interested in levels of exposure and its health effects, it would be impossible to consider either of these without knowing what radionuclides were released. A person who absorbs Iodine-13 which has a half life of 8days emits all of its radiation in the thyroid, the whole body dose is irrelevant to the type of damage caused, in the same way calcium-45 is deposited in bone. Several isotopes may be excreted very quickly which will limit exposure. Several people have already made this point. I am curious to know how you would calculate exposure or the health effects without reference to these issues and I don't think that the only thing being discussed was whole dose and presumably whole body exposure, it would be pointless to do so.
Still some posts can be misleading and I'm not immune to this, still few people are.

 

[mfb]

We know which radionuclides were released, how and where they were absorbed by the body and how long their biological lifetime is. All the death toll estimates cited here are based on this knowledge.

 

[Stephen22]

It's known that 50 people died from ARS as a result of being in close proximity to the source of the radiation, but beyond that, it's all just estimates as far as how many people got cancer as a result of the accident. There are many environmental factors that can cause an increased risk of cancer (not just radiation), and it's difficult to impossible to determine with absolute certainty exactly how many cases of cancer since the disaster were caused by the radiation vs. other factors that changed around that time frame. Not only that, but it's likely that some potential causes of cancer are still unknown, and therefore not all of the variables are necessarily accounted for. Furthermore, some organizations have a political agenda, whether that's downplaying or exaggerating the risks associated with nuclear energy, and their "estimates" could be distorted in favor of their bias.

 

[Laroxe]

I'm not sure that looking at the dose a person receives is really that useful. The increase in thyroid cancer was not really an issue about the dose, it was the fact that the dose was in a form that was readily ingested and incorporated into our physiological processes. Really we need to know what isotopes were released and the potential that people may have ingested or inhales these isotopes. I used to live near Sellafield in the UK and during their annual leaks, radioiodine was always a cause for concern. However despite the problems there was never any convincing evidence of higher rates of cancer in the area.