April 08, 2011

Responding to questions about the Hiroshima long term radiation study

There are some people who are saying that the Hiroshima long term radiation study has flaws in it

They referred to a 16 pager that claims issues with the study. The counter references are mostly not in any peer reviewed journals. So if the claim of improper cohorts has some validity there is still the raw data for re-comparing to different cohorts. So where are those journal comparisons ?

They are claiming that instead of 5% more cancer risk it could be 40%. That is for far higher radiation dosages at Hiroshima and Nagasaki.

Other studies back up the no adverse health effects from radiation below 400 mSv

They are claiming that the below one rad levels were not measured / misassigned based on definitions.

For x-rays and gamma rays, 1 rad = 1 rem = 10 mSv

For neutrons, 1 rad = 5 to 20 rem (depending on energy level) = 50-200 mSv

For alpha radiation (helium-4 nuclei), 1 rad = 20 rem = 200 mSv

Taiwan had 10,000 people exposed to 400 mSv over 9-20 years. No incremental health effects.

Taiwan radiation incident - Is Chronic Radiation an Effective Prophylaxis Against Cancer?
Journal of American Physicians and Surgeons Volume 9 Number 1 Spring 2004

An extraordinary incident occurred 20 years ago in Taiwan. Recycled steel, accidentally contaminated with cobalt-60 (half-life: 5.3 y), was formed into construction steel for more than 180 buildings, which 10,000 persons occupied for 9 to 20 years. They unknowingly received radiation doses that averaged 0.4 Sv - a collective dose of 4,000 person-Sv.

Based on the observed seven cancer deaths, the cancer mortality rate for this population was assessed to be 3.5 per 100,000 person-years. Three children were born with congenital heart malformations, indicating a prevalence rate of 1.5 cases per 1,000 children under age 19.

The average spontaneous cancer death rate in the general population of Taiwan over these 20 years is 116 persons per 100,000 person-years. Based upon partial official statistics and hospital experience, the prevalence rate of congenital malformation is 23 cases per 1,000 children. Assuming the age and income distributions of these persons are the same as for the general population, it appears that significant beneficial health effects may be associated with this chronic radiation exposure.

Epidemiological studies of cancer in aircrew.

Exposure to cosmic ionising radiation, in addition to other specific occupational risks, is of concern to aircrew members. Epidemiological studies provide an objective way to assess the health of this occupational group. We systematically reviewed the epidemiological literature on health of aircrew members since 1990, focusing on cancer as the endpoint of interest. Sixty-five relevant publications were identified and reviewed. Whereas overall cancer incidence and mortality was generally lower than in the comparison population, consistently elevated risks were reported for breast cancer incidence in female aircrew members and for melanoma in both male and female aircrew members. Brain cancer was increased in some studies among pilots. Occasionally trends of increasing cancer mortality or incidence with increasing estimated radiation dose were reported. Ionising radiation is considered to contribute little if at all to the elevated risks for cancers among aircrew, whereas excess ultraviolet radiation is a probable cause of the increased melanoma risk.

Institute for Medical Biostatistics, Epidemiology and Informatics (IMBEI), University Medical Center, Johannes Gutenberg-University, Langenbeckstr. 1, D-55101 Mainz, Germany.

There are about 250,000 pilots and flight attendants in the world.

Another 450,000 pilots of other types.

Full time pilots and flight attendants can get two to four times the regular amount of radiation in a year.

2.2 mSv: airline crew member, short flights for one year
3-6 mSv: airline crew member, cross-country flights, 900 hrs/yr for one year
10 mSv: cooking with natural gas (radon) for a year
5-15 mSv: one full-body CT scan for about 20 minutes
6-18 mSv: one chest CT scan for about 10 minutes
9 mSv: airline crew member, polar flights, such as Tokyo-NYC, 900 hrs/yr for one year
13 mSv: smoking one pack of cigarettes per day for a year
20 mSv: nuclear plant worker, maximum 5-year average*+
50 mSv: nuclear plant worker, maximum total exposure in one year
50-100 mSv: changes in blood chemistry
100 mSv: lowest clearly carcinogenic level; 1 millimort

So airline crew flying long haul routes for ten years would get 30-90 mSv and for 20 year would get 60-180 mSv

Where is the increased cancer ? The studies do not find it. Not for the 10,000 people in Taiwan and not for the airline crews

Nuclear weapons

Countries get nuclear weapons before they get commercial nuclear power plants. There were 20,000 nuclear bombs before the first commercial nuclear reactor was built. Only India and Pakistan misused any of the commercial nuclear technology to get their bombs. More people were killed in the firebombing of Tokyo in WW2 using petrochemical weapons than were killed at Hiroshima. If Operation rolling Thunder over 2 years in Vietnam by the US had been targeting cities instead of jungle, the petrochemical bombs dropped would have killed a lot more people. The US could easily have devastated the cities of northern Vietnam. Instead "only" 2 million people were killed in the Vietnam war.

The Precautionary principle ignores the deaths from the existing primary power sources of coal and oil and natural gas. Natural gas is a primary source of Radon. But the deaths from those are mainly from the air pollution. Outdoor air pollution prematurely kills 1.2 million people each year worldwide. Avg life shortened by 14 years. Also plenty of birth defects and damage to babies from the air pollution.

Air pollution annual deaths are worse than all of the nuclear power scenarios.

What do you propose to do about the air pollution deaths? France has better air quality and lower deaths because of their 75% nuclear power generation. Tens of millions go to France for vacation. Traveling from where they live to get closer to nuclear power plants. How many international people are traveling to the cities in China for non-business purposes when those cities have massive air pollution from coal ?

Are you going to the Appalachians to look at the forests where there is coal mining. 7% have been blown up for mountain top removal mining. Are you using the thousands of square miles of land which are now underneath containment ponds for the coal slag or the sludge from blown up mountain tops and forests ?

You talk about the geopolitics of nuclear power. Are you claiming no geopolitical effects from oil demand and usage and oil access ?

If the US which has thousands of nuclear weapons already and China which has hundreds and both have commercial nuclear power were to ramp up commercial nuclear power to displace coal and reduce oil usage with electrification of transportation that would reduce world coal usage by 66%. The new nuclear plants could be built on existing nuclear sites and replace the coal burner at coal plants. Air pollution deaths could drop by over 300,000 per year in China and by 20,000 per year in the USA (not all air pollution deaths would go away as there would still be other sources). Also the oil demand could drop by 15 million barrels per day. 40% of the freight rail in the USA and more in China would be saved along with their oil usage by not having to move over 4 billion tons of coal. How do those benefits weight against any incremental risks ? Pretty damn good and overwhelming.

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