Sunday, July 1, 2012

Debating Radiation Safety: Background Information


Radiation Effects Research

The history of research on radiation exposure may be among the most politicized body of public health research because both the nuclear industry and governments with nuclear weapons’ programs have a shared vested interest in trivializing the effects of ionizing radiation despite almost a century of research documenting harmful effects from even low levels of exposure, particularly when radionuclides are ingested.

This post will outline these debates in order to address more fully the implications of the Fukushima nuclear disaster. Given the complexity of the playing field for those contesting effects it will be helpful to identify the central actors and key debates.

Central Actors in the Debate About Radiation Safety. 

In general, there are three main types of players in the debates about radiation safety.

First, there are national and international governmental agencies tasked with nuclear regulation and safety. The first national regulatory agency in the US was the Atomic Energy Commission, instituted in 1946 and tasked with both nuclear promotion and regulation.

The U.S. Nuclear Regulatory Agency (NRC) replaced the Atomic Energy Commission in 1974 due to public concern about the politicization of the AEC. Various environmental agencies within the U.S. are tasked with monitoring radiation levels in water and air (the Environmental Protection Agency) and food and milk (the Food and Drug Administration).

Japan has a Nuclear Safety Commission with functions similar to the US NRC. After the Fukushima disaster Japan tasked the Ministry of Education, Culture, Sports, Science and Technology (MEXT) with monitoring of, and publication of data about, environmental radiation levels (http://www.nsc.go.jp/NSCenglish/index.htm).

The first international regulatory agency was the International Atomic Energy Commission, established in 1957 after 81 nations approved the IAEA Statute (http://www.iaea.org/About/history.html). The statute outlines the agency’s three responsibilities: “nuclear verification and security, safety and technology transfer." The regulatory work conducted by the IAEA is in principle informed by published research on radiation safety. T

The United Nations publishes material on radiation risks and safety under the auspices of The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). UNSCEAR was established in 1955. Its mandate entails assessing and reporting levels and effects of exposure to ionizing radiation (http://www.unscear.org/unscear/en/about_us.html). UNSCEAR was supposed to serve as “watchdog” for the safety of IAEA policies. 

The second group of actors in the debates about radiation safety includes national and international organizations usually comprised of academics making policy recommendations about the relative safety of exposure levels.

One of the first of these organizations was the U.S. Advisory commission on X-Ray and Radium Protection that was established in 1928. This organization changed its name and became the National Committee on Radiation Protection in 1946 (NCRP).

The International Committee on Radiation Protection was established also in 1928 (ICRP). Since 1928 the ICRP has maintained the “International System of Radiological Protection” used as a common basis for developing radiological protection standards and legislations. The NCRP and ICRP make recommendations, but lack governmental authority.

A related source of recommendations on radiation comes from non-governmental national and international science academies. In the U.S., the National Academies of Science has produced research reviews of the biological effects of radiation since they were tasked by the Atomic Energy Commission to produce the first independent assessment of radiation effects, the 1955 BEAR report.

The U.S. National Academies of Sciences issues a wide range of reports about radiation safety and their publication series on the Biological Effects of Ionizing Radiation (BEIR) is updated regulatory. The most current version is the BEIR VII report. In Europe, an independent committee named the European Commission on Radiological Protection (ECRP) recently made new recommendations for radiological protection based on some differences with the ICRP in interpreting dose effects, particularly for internal emitters.

The third group of actors in the debate on radiation safety is a diverse assortment of independent scientists and activists. This diverse group can be divided between

a) those whose research is “pro-nuclear” and is funded by the nuclear industry or pro-nuclear government agencies, especially the U.S. Department of Energy

b) those whose research is “anti-nuclear” and is funded by environment organizations, such as Beyond Nuclear (http://www.beyondnuclear.org/) and Greenpeace, or is simply conducted entirely independently (e.g., Rosalie Bertell and Clyde Stagner).

IAEA funding to MIT University results a considerable amount of pro-nuclear research emanating from that institution.

In contrast, a good example of an anti-nuclear non-governmental organization is the U.S. Radiation and Public Health Project (RPHP) founded in 1988 by Jay M. Gould, Benjamin A. Goldman, and Ernest Sternglass and sponsored by the United Church of Christ Commission for Racial Justice (http://www.radiation.org/about/index.html). Currently the organization is directed by Joseph Mangano.

Contemporary independent anti-nuclear activists include Helen Caldicott and Chris Busby, that latter of whom has conducted independent research on ionizing radiation, but also served as Chairman for the ECRP.

Central Debates in Radiation Safety

The various actors outlined above are contenders in the playing field of radiation safety. There are two major debates at issue.

The first debate concerns the legitimacy of the linear, no-threshold model, which holds there is no safe level of exposure. 

The linear, no-threshold model has been legitimized by the US National Academies of Science and accepted by the major governmental and non-governmental actors, including the ICRP, the US NCRP, and the U.S. EPA.

However, despite widespread acceptance, scientists funded by industry and government grants working in the US and abroad continue to push the “hormesis” hypothesis that holds that there is a threshold under which exposure to ionizing radiation can be considered safe.

Furthermore, a nation’s acceptance of the legitimacy of the linear, no-threshold model does not necessarily mean ready translation into protective policies. For example, although the US EPA adopts a precautionary approach toward regulatory radiation levels in water, the U.S. FDA allows a much greater concentration of radiation in food and milk than allowed by the EPA in water because the FDA adopts a cost-benefit risk model when setting its levels of concern.

The second debate concerns the role of internal emitters versus external exposure to radiation. Scientists have known definitely since the 1930s that ingestion of radionuclides is far more biologically radiotoxic than external exposure to radiation. Despite empirical evidence, the U.S. Atomic Energy Commission denied this finding in order to limit resistance against atmospheric testing in the 1950s and 1960s.

Even today, efforts are made by some nuclear authorities to confuse public perceptions about the relative risks of internal and external radiation exposure by comparing exposure to nuclear fallout to the gamma radiation received while flying on an airplane. Furthermore, even among experts, debate exists on the correct procedures for predicting the effects of internally ingested radionuclides on organs.

The ICRP model averages the radiation dose produced by an ingested alpha particle across the entirety of the impacted organ when calculating the “absorbed dose.”

In contrast, the ECRP contends that the dose-effects from ingestion of radionuclides should be examined in terms of their more narrowly focused effects on directly targeted and bystander cells. The ECRP model predicts greater genetic damage from internally ingested radionuclides as a function of this focused look at targeted effects.

Resources and Related Posts

Stagner, Clyde. Hidden Tritium http://www.amazon.com/Hidden-Tritium-Clyde-Stagner/dp/1618631594/ref=sr_1_1?s=books&ie=UTF8&qid=1340555839&sr=1-1&keywords=hidden+tritium 

ICRP VERSUS ECRP
http://majiasblog.blogspot.com/2012/06/icrp-versus-ecrp.html 

 Bias in the First US Study on the Effects of Radiation
http://majiasblog.blogspot.com/2012/06/systematic-study-in-first-bear-study-on.html

Discussion of internal emitters

http://majiasblog.blogspot.com/2012/05/on-internal-emitters.html




http://majiasblog.blogspot.com/2011/08/debating-dose.html 
 



1 comment:

  1. The government and the people should be vigilant about Radiation Safety. They should be knowledgeable and responsible on proper usage and disposal of these hazardous things.

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