Bernard Cohen
Encyclopedia
Bernard Leonard Cohen born June 14, 1924 in Pittsburgh, is Professor Emeritus of Physics
at the University of Pittsburgh
. Professor Cohen has been a staunch opponent to the so called Linear no-threshold model
(LNT) which postulates there exists no safe threshold for radiation exposure. His views, what was in the 1980s and 1990s considered a self-marginalizing posture had become somewhat mainstream some 20 years later.
A conclusion with an update to the landmark study published 1995, continues: "Since no other plausible explanation has been found after years of effort by myself and others, I conclude that the most plausible explanation for our discrepancy is that the linear-no threshold theory fails, grossly over-estimating the cancer risk in the low dose, low dose rate region. There are no other data capable of testing the theory in that region.
An easy answer to the credibility of this conclusion would be for someone to suggest a potential not implausible explanation based on some selected variables. I (or he) will then calculate what values of those variables are required to explain our discrepancy. We can then make a judgement on the plausibility of that explanation. To show that this procedure is not unreasonable, I offer to provide a not-implausible explanation for any finding of any other published ecological study. This alone demonstrates that our work is very different from any other ecological study, and therefore deserves separate consideration."
His debates in academic periodicals and published correspondence with R. William Field
, Brian J. Smith
(assistant professor of biostatistics
, University of Iowa
), Jerry Puskin (from the U.S. Environmental Protection Agency
), Sarah Darby
, and Sir Richard Doll
and others regarding his radon-related ecologic studies are well known.
In March, 2011, Professor Cohen stated, reflecting on his study and its controversial findings that low levels of radiation can have beneficial health effects and reduce the risks of cancer, "There is evidence on both sides. Whether low-level radiation is protective against cancer, a theory called radiation hormesis
, is debated in the scientific community. Furthermore, "...[on his viewpoint, and its' support found in his exhaustive studies] it could go further and say that no confounding factors (like socio-economic, geography, ethnicity, medical care access, and beyond 500 explored in the analysis) can explain the results. However, my study was designed to test the assumption that the danger of radiation is simply proportional to the radiation dose, which is the only evidence that low-level radiation may be harmful. My conclusion was that that assumption is false.". Reputable scientists disagree about that; the debate is far from over. Given the uncertain effects of low-level radiation, there is a pressing need for good quality research in this area.
Subsequent research would join a profound array of positions including a 1982 United Nations
' work-group study -UNSCEAR- concluding: "There appear to be no nonspecific effects from low doses
of radiation that result in a shortening of the life span."
) since 1958 as Professor of Physics, Adjunct Prof. of Chemistry, Adjunct Prof. of Chemical and Petroleum Engineering, Adjunct Prof. of Radiation Health at the Graduate School of Public Health; there also as Adjunct Prof. of Environmental and Occupational Health. He was awarded Professor-Emeritus standing in 1994, his current status.
From 1965-1978 he was Director of the Scaife Nuclear Laboratory.
A testimony to his conviction on the human safety of background low-level radiation was his offering rewards of up to $10,000 if people provided evidence the inverse association he found between radon
(county averages) and lung cancer
(county averages) was due to some factor other than failure of the linear-no threshold theory. Puskin, Smith, Field and others have claimed that his findings are due in part to his inability to control for the inverse association between smoking and radon.
When Ralph Nader
described plutonium
as "the most toxic substance known to mankind", Cohen, then a tenured professor, offered to consume on camera as much plutonium oxide as Nader could consume of caffeine
, the stimulant found in coffee and other beverages, which in its pure form has an oral of 192 milligrams per kilogram in rats.
Arabic, Nuclear Science and Society (1974), Before It's Too Late: A Scientist's Case for Nuclear Power (1983), and The Nuclear Energy Option, Alternative for the Nineties, (1990) in translation for Japanese and Spanish. He has written about 135 research papers on basic nuclear physics
, about 300 scientific papers on energy and environment (e.g. nuclear power
, health effects of radiation
, radioactive waste
, risks in our society), and about 80 articles in popular magazines such as Physics and Society, National Review
, Oui
, Science Digest
, Catholic Digest
, and Scientific American
. He has authored scientific studies and editorial contributions on a vast array of subjects in nuclear industry trade journals such as Public Utilities Fortnightly, Reviews of Modern Physics
, Nuclear Engineering International, and American Journal of Physics
.
. He was also elected Chairman of the American Physical Society
, Division of Nuclear Physics (1974–75).
Dr. Cohen received the 1992 Distinguished Scientific Achievement Award from the Health Physics Society, and the 1996 Walter H. Zinn Award from the American Nuclear Society
(ANS), to recognize him "for a notable and sustained contribution to the nuclear power industry that has not been widely recognized." The ANS granted Cohen also its 1985 "Public Information Award", and its 1996 "Special Award", for his "meritorious contributions in research" on Linear Dose Model [Versus] Other Models for Critical Dose Values. He was elected to member of the National Academy of Engineering
in 2003, "for fundamental contributions to our understanding of low-level radiation" and Chairman of the American Nuclear Society
Division of Environmental Sciences (1980–81).
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...
at the University of Pittsburgh
University of Pittsburgh
The University of Pittsburgh, commonly referred to as Pitt, is a state-related research university located in Pittsburgh, Pennsylvania, United States. Founded as Pittsburgh Academy in 1787 on what was then the American frontier, Pitt is one of the oldest continuously chartered institutions of...
. Professor Cohen has been a staunch opponent to the so called Linear no-threshold model
Linear no-threshold model
The linear no-threshold model is a method for predicting the long term, biological damage caused by ionizing radiation and is based on the assumption that the risk is directly proportional to the dose at all dose levels....
(LNT) which postulates there exists no safe threshold for radiation exposure. His views, what was in the 1980s and 1990s considered a self-marginalizing posture had become somewhat mainstream some 20 years later.
No-threshold and plutonium toxicity debates
He asserts: "All estimates of the cancer risk from low level radiation are based on the linear-no threshold theory (LNT) which is based solely on largely discredited concepts of radiation carcinogenesis, with no experimental verification in the low dose region of the most important applications. These risk estimates are now leading to the expenditure of tens of billions of dollars to protect against dangers whose existence is highly questionable. It is therefore of utmost importance to test the validity of this theory."A conclusion with an update to the landmark study published 1995, continues: "Since no other plausible explanation has been found after years of effort by myself and others, I conclude that the most plausible explanation for our discrepancy is that the linear-no threshold theory fails, grossly over-estimating the cancer risk in the low dose, low dose rate region. There are no other data capable of testing the theory in that region.
An easy answer to the credibility of this conclusion would be for someone to suggest a potential not implausible explanation based on some selected variables. I (or he) will then calculate what values of those variables are required to explain our discrepancy. We can then make a judgement on the plausibility of that explanation. To show that this procedure is not unreasonable, I offer to provide a not-implausible explanation for any finding of any other published ecological study. This alone demonstrates that our work is very different from any other ecological study, and therefore deserves separate consideration."
His debates in academic periodicals and published correspondence with R. William Field
R. William Field
R. William Field is an academic scholar and Professor in the of Epidemiology within the College of Public Health at the University of Iowa. He received a BS and MS degree in Biology from Millersville University of Pennsylvania and a PhD in Preventive Medicine from the College of Medicine at the...
, Brian J. Smith
Brian J. Smith
Brian J. Smith is an American actor who is known for his role as Trey in the 2006 independent film Hate Crime and as series regular Lt. Matthew Scott in the military science fiction television series, Stargate Universe....
(assistant professor of biostatistics
Biostatistics
Biostatistics is the application of statistics to a wide range of topics in biology...
, University of Iowa
University of Iowa
The University of Iowa is a public state-supported research university located in Iowa City, Iowa, United States. It is the oldest public university in the state. The university is organized into eleven colleges granting undergraduate, graduate, and professional degrees...
), Jerry Puskin (from the U.S. Environmental Protection Agency
United States Environmental Protection Agency
The U.S. Environmental Protection Agency is an agency of the federal government of the United States charged with protecting human health and the environment, by writing and enforcing regulations based on laws passed by Congress...
), Sarah Darby
Sarah Darby
Professor Sarah Darby is a British epidemiologist. In recent years, her research has concerned evaluating the beneficial effects of giving up smoking, the risk of lung cancer from residential radon and treatments for early breast cancer....
, and Sir Richard Doll
Richard Doll
Sir William Richard Shaboe Doll CH OBE FRS was a British physiologist who became the foremost epidemiologist of the 20th century, turning the subject into a rigorous science. He was a pioneer in research linking smoking to health problems...
and others regarding his radon-related ecologic studies are well known.
In March, 2011, Professor Cohen stated, reflecting on his study and its controversial findings that low levels of radiation can have beneficial health effects and reduce the risks of cancer, "There is evidence on both sides. Whether low-level radiation is protective against cancer, a theory called radiation hormesis
Radiation hormesis
Radiation hormesis is the hypothesis that low doses of ionizing radiation are beneficial, stimulating the activation of repair mechanisms that protect against disease, that are not activated in absence of ionizing radiation...
, is debated in the scientific community. Furthermore, "...[on his viewpoint, and its' support found in his exhaustive studies] it could go further and say that no confounding factors (like socio-economic, geography, ethnicity, medical care access, and beyond 500 explored in the analysis) can explain the results. However, my study was designed to test the assumption that the danger of radiation is simply proportional to the radiation dose, which is the only evidence that low-level radiation may be harmful. My conclusion was that that assumption is false.". Reputable scientists disagree about that; the debate is far from over. Given the uncertain effects of low-level radiation, there is a pressing need for good quality research in this area.
Subsequent research would join a profound array of positions including a 1982 United Nations
United Nations
The United Nations is an international organization whose stated aims are facilitating cooperation in international law, international security, economic development, social progress, human rights, and achievement of world peace...
' work-group study -UNSCEAR- concluding: "There appear to be no nonspecific effects from low doses
of radiation that result in a shortening of the life span."
Scholarly achievements
Professor Cohen earned his under-graduate degree from Case-Western Reserve University [1944], Masters from University of Pittsburgh [1947] and Ph.D from Carnegie-Mellon University [1950]. He has taught at UP (PittPitt
Pitt is a surname of English origin. Used on its own, in Europe or History it most commonly refers to one of two British statesmen:*William Pitt, 1st Earl of Chatham , British Prime Minister & 1st Earl of Chatham 1766–1768** Pittsburgh, Pennsylvania was named for Pitt the Elder and is...
) since 1958 as Professor of Physics, Adjunct Prof. of Chemistry, Adjunct Prof. of Chemical and Petroleum Engineering, Adjunct Prof. of Radiation Health at the Graduate School of Public Health; there also as Adjunct Prof. of Environmental and Occupational Health. He was awarded Professor-Emeritus standing in 1994, his current status.
From 1965-1978 he was Director of the Scaife Nuclear Laboratory.
A testimony to his conviction on the human safety of background low-level radiation was his offering rewards of up to $10,000 if people provided evidence the inverse association he found between radon
Radon
Radon is a chemical element with symbol Rn and atomic number 86. It is a radioactive, colorless, odorless, tasteless noble gas, occurring naturally as the decay product of uranium or thorium. Its most stable isotope, 222Rn, has a half-life of 3.8 days...
(county averages) and lung cancer
Lung cancer
Lung cancer is a disease characterized by uncontrolled cell growth in tissues of the lung. If left untreated, this growth can spread beyond the lung in a process called metastasis into nearby tissue and, eventually, into other parts of the body. Most cancers that start in lung, known as primary...
(county averages) was due to some factor other than failure of the linear-no threshold theory. Puskin, Smith, Field and others have claimed that his findings are due in part to his inability to control for the inverse association between smoking and radon.
When Ralph Nader
Ralph Nader
Ralph Nader is an American political activist, as well as an author, lecturer, and attorney. Areas of particular concern to Nader include consumer protection, humanitarianism, environmentalism, and democratic government....
described plutonium
Plutonium
Plutonium is a transuranic radioactive chemical element with the chemical symbol Pu and atomic number 94. It is an actinide metal of silvery-gray appearance that tarnishes when exposed to air, forming a dull coating when oxidized. The element normally exhibits six allotropes and four oxidation...
as "the most toxic substance known to mankind", Cohen, then a tenured professor, offered to consume on camera as much plutonium oxide as Nader could consume of caffeine
Caffeine
Caffeine is a bitter, white crystalline xanthine alkaloid that acts as a stimulant drug. Caffeine is found in varying quantities in the seeds, leaves, and fruit of some plants, where it acts as a natural pesticide that paralyzes and kills certain insects feeding on the plants...
, the stimulant found in coffee and other beverages, which in its pure form has an oral of 192 milligrams per kilogram in rats.
Publications
Professor Cohen has written six books, including Heart of the Atom (1967) with translations in French, German, Italian, and Japanese, Concepts of Nuclear Physics (1970) with translation inArabic, Nuclear Science and Society (1974), Before It's Too Late: A Scientist's Case for Nuclear Power (1983), and The Nuclear Energy Option, Alternative for the Nineties, (1990) in translation for Japanese and Spanish. He has written about 135 research papers on basic nuclear physics
Nuclear physics
Nuclear physics is the field of physics that studies the building blocks and interactions of atomic nuclei. The most commonly known applications of nuclear physics are nuclear power generation and nuclear weapons technology, but the research has provided application in many fields, including those...
, about 300 scientific papers on energy and environment (e.g. nuclear power
Nuclear power
Nuclear power is the use of sustained nuclear fission to generate heat and electricity. Nuclear power plants provide about 6% of the world's energy and 13–14% of the world's electricity, with the U.S., France, and Japan together accounting for about 50% of nuclear generated electricity...
, health effects of radiation
Radiation
In physics, radiation is a process in which energetic particles or energetic waves travel through a medium or space. There are two distinct types of radiation; ionizing and non-ionizing...
, radioactive waste
Radioactive waste
Radioactive wastes are wastes that contain radioactive material. Radioactive wastes are usually by-products of nuclear power generation and other applications of nuclear fission or nuclear technology, such as research and medicine...
, risks in our society), and about 80 articles in popular magazines such as Physics and Society, National Review
National Review
National Review is a biweekly magazine founded by the late author William F. Buckley, Jr., in 1955 and based in New York City. It describes itself as "America's most widely read and influential magazine and web site for conservative news, commentary, and opinion."Although the print version of the...
, Oui
Oui (magazine)
Oui is a men's adult pornographic magazine published in the USA and featuring explicit nude photographs of models, with full page pin-ups, centerfolds, interviews and other articles, and cartoons.- Playboy years :...
, Science Digest
Science Digest
Science Digest was a monthly American magazine published by the Hearst Corporation from 1937 through 1986. It initially had an 8 x 5 inch format with about 100 pages, and was targeted at persons with a high school education level...
, Catholic Digest
Catholic Digest
Catholic Digest is an American Roman Catholic monthly magazine.It was founded in 1936 and today circulation totals 300,000.In December 2001, the French Roman Catholic media group Bayard Presse purchased the magazine from University of St. Thomas...
, and Scientific American
Scientific American
Scientific American is a popular science magazine. It is notable for its long history of presenting science monthly to an educated but not necessarily scientific public, through its careful attention to the clarity of its text as well as the quality of its specially commissioned color graphics...
. He has authored scientific studies and editorial contributions on a vast array of subjects in nuclear industry trade journals such as Public Utilities Fortnightly, Reviews of Modern Physics
Reviews of Modern Physics
The Reviews of Modern Physics is a journal of the American Physical Society. The journal started in paper form. All volumes are also online by subscription.Issue 1, Volume 1 consisted of the review by...
, Nuclear Engineering International, and American Journal of Physics
American Journal of Physics
The American Journal of Physics is a monthly, peer-reviewed scientific journal published by the American Association of Physics Teachers and the American Institute of Physics. The editor is Jan Tobochnik of Kalamazoo College.-Aims and scope:...
.
Awards and honors
Dr. Cohen received in 1981 the Tom W. Bonner Prize in Nuclear Physics from the American Physical SocietyAmerican Physical Society
The American Physical Society is the world's second largest organization of physicists, behind the Deutsche Physikalische Gesellschaft. The Society publishes more than a dozen scientific journals, including the world renowned Physical Review and Physical Review Letters, and organizes more than 20...
. He was also elected Chairman of the American Physical Society
American Physical Society
The American Physical Society is the world's second largest organization of physicists, behind the Deutsche Physikalische Gesellschaft. The Society publishes more than a dozen scientific journals, including the world renowned Physical Review and Physical Review Letters, and organizes more than 20...
, Division of Nuclear Physics (1974–75).
Dr. Cohen received the 1992 Distinguished Scientific Achievement Award from the Health Physics Society, and the 1996 Walter H. Zinn Award from the American Nuclear Society
American Nuclear Society
The American Nuclear Society is an international, not-for-profit 501 scientific and educational organization with a membership of approximately 11,000 scientists, engineers, educators, students, and other associate members. Approximately 900 members live outside the United States in 40 countries....
(ANS), to recognize him "for a notable and sustained contribution to the nuclear power industry that has not been widely recognized." The ANS granted Cohen also its 1985 "Public Information Award", and its 1996 "Special Award", for his "meritorious contributions in research" on Linear Dose Model [Versus] Other Models for Critical Dose Values. He was elected to member of the National Academy of Engineering
National Academy of Engineering
The National Academy of Engineering is a government-created non-profit institution in the United States, that was founded in 1964 under the same congressional act that led to the founding of the National Academy of Sciences...
in 2003, "for fundamental contributions to our understanding of low-level radiation" and Chairman of the American Nuclear Society
American Nuclear Society
The American Nuclear Society is an international, not-for-profit 501 scientific and educational organization with a membership of approximately 11,000 scientists, engineers, educators, students, and other associate members. Approximately 900 members live outside the United States in 40 countries....
Division of Environmental Sciences (1980–81).
External links
- Bernard Cohen home page. Contains full text of The Nuclear Energy Option (ISBN 0-306-43567-5).
- The Myth of Plutonium Toxicity paper in which Cohen discusses his challenge to Nader.