4,000 is a conservative estimate. http://www.chernobylreport.org suggests 30,000 to 60,000. Cancer deaths are hard to attribute while workers falling off the roof installing solar equipment... not so much.
With Chernobyl it's also worth bearing in mind how much worse it could have been easily if the cleanup workers hadn't done their jobs right:
"There was a moment when there was the danger of a nuclear explosion, and they had to get the water out from under the reactor, so that a mixture of uranium and graphite wouldn't get into it - with the water, they would have formed a critical mass. The explosion would have been between three and five megatons. This would have meant that not only Kiev and Minsk, but a large part of Europe would have been uninhabitable. Can you imagine it? A European catastrophe."
> The explosion would have been between three and five megatons.
This is ridiculous and obviously wrong. A chain reaction with moderated neutrons with water and graphite could not, even in principle, produce that much energy.
It is based on the UNSCEAR report, which I consider to be the authoritative source. The following WHO write-up provides a full breakdown by category. [1] The 30-60K number is scaremongering. The UNSCEAR report is about 600 pages and took 20 years to compile, and included 8 intergovernmental organizations and all the local affected governments.
"Alongside radiation-induced deaths and diseases, the report labels the mental health impact of Chernobyl as 'the largest public health problem created by the accident' and partially attributes this damaging psychological impact to a lack of accurate information." [1] This was a material problem, as many people killed themselves believing they were "contaminated" when, in reality, that were just fine.
As the link covers (both yours and mine), the primary cancers attributable to Chernobyl are thyroid cancer, due to radioactive iodine. Thyroid cancers have a 99% survival rate. This is curiously omitted in your link. Thankfully, I-131 has a half-life of just 8 days and is long, long gone.
Major incidents should not, in my opinion, dominate the discourse. After all, we're fine with hydro power when the Bangqiao Dam incident killed up to 200,000 people in one fell swoop. A single dam failure could easily cause drastically more harm than a nuclear incident.
> "Can you imagine it? A European catastrophe."
26% of all power generated in Europe comes from nuclear today. Luckily, they have learned from their mistakes and improved processes and safety measures.
[edit] The discrepancy in your link I suspect comes from this: "Excess cancer deaths can be estimated from published collective doses."
Further, I suspect the actual extent of future deaths will be lower than even UNSCEAR. They support the "linear no-threshold dose response" model, where any amount of increased radiation exposure leads to a proportional increase cancer deaths. However, this model is being challenged, as experimental evidence shows this is not consistent with biological and experimental data [2].
With Chernobyl it's also worth bearing in mind how much worse it could have been easily if the cleanup workers hadn't done their jobs right:
"There was a moment when there was the danger of a nuclear explosion, and they had to get the water out from under the reactor, so that a mixture of uranium and graphite wouldn't get into it - with the water, they would have formed a critical mass. The explosion would have been between three and five megatons. This would have meant that not only Kiev and Minsk, but a large part of Europe would have been uninhabitable. Can you imagine it? A European catastrophe."
https://www.theguardian.com/environment/2005/apr/25/energy.u...