Nuclear Q&A: Answers on Chernobyl, Fukushima Cleanup, and Energy Risks

1/5   in the series Nuclear Q&A

These are the first responses from AIChE's Nuclear Engineering Division (NED) to readers' questions about nuclear energy and Fukushima. More to come!

Rich, a student from Chicago asks:
Death estimates due to Chernobyl vary widely. Some reports suggest that only 54 people died. Other studies conclude as many as 1 million. What are the more accurate numbers?

This is a very hard number to pin down and there is definitely a wide range of answers reported in the literature. The most exhaustive study on health effects of the Chernobyl accident was carried out by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). They have published a number of reports on the topic, including long-term tracking of cancer rates of exposed individuals. You can find these reports here.

In short, the UNSCEAR Report in 2008 state that 134 emergency workers and plant personnel received enough radiation dose to result in Acute Radiation Syndrome (ARS). Of these workers, ARS proved to be fatal for 28 workers. As of 2006 an additional 19 workers have died, but there was no link between their cause of death and the radiation exposure. The release of 131I which contaminated milk has been attributed to more than 6,000 cases of thyroid cancer, and 15 of these cases were fatal. Based on more than 20 years of study, the report concludes that while significant numbers of individuals (particularly emergency and recovery workers) have increased incidence of cataracts and certain cancers, no other serious health effects have been reported.

Richard, medic and green campaigner, Somerset, UK,

What is holding back Tepco from filtering the gaseous and water wastes on the Fukushima site along the lines outlined here?

It is our understanding that Tepco has contracted Areva to provide decontamination of the cooling water using a well-established technology, but we don't know what efforts are being undertaken to filter the gaseous effluents. It's worth remembering that most of the gaseous radioactivity is associated with radioactive xenon, which has extremely low impact to human health because it doesn't accumulate in the body, and iodine-131. Iodine-131 has only an eight-day half life and decays to stable xenon so does not remain in the environment for very long. There is a balance of health risk between that to plant operators (in fitting equipment and dealing with wastes in a radioactive environment) and that to the public to be considered here.

Robert, technical advisor, Argentina

, asks:
With all the talk about risks between energy sources, has there been a systematic attempt to evaluate different energy sources based on cost per kW? For example, nuclear makes big headlines with single catastrophes like the recent event and Chernobyl. But coal claims lives in smaller, more frequent accidents. Similar with health effects, some risks are built into our social system so are not accurately accounted for. Any way to put a number on these to compare same to same?

These comparisons have certainly been made, and we will refer you to some of the sources of information contained in the Nuclear Engineering Division's Position Statement, published in the July 2010 issue of CEP. The Position Statement can also be found on our new updated website:


Mal Content's picture

There are four 100 m tall self supporting towers at the Fukushima campus. They have large diameter pipes in them. What are these for?