Biological Effects of Radiation

Biological Effects of Radiation

Radiation is all around us. It is naturally present in our environment and has been since the birth of this planet. Consequently, life has evolved in an environment which has significant levels of ionizing radiation. It comes from outer space (cosmic), the ground (terrestrial), and even from within our own bodies. It is present in the air we breathe, the food we eat, the water we drink, and in the construction materials used to build our homes. Certain foods such as bananas and brazil nuts naturally contain higher levels of radiation than other foods. Brick and stone homes have higher natural radiation levels than homes made of other building materials such as wood. Our nation's Capitol, which is largely constructed of granite, contains higher levels of natural radiation than most homes.

Levels of natural or background radiation can vary greatly from one location to the next. For example, people residing in Colorado are exposed to more natural radiation than residents of the east or west coast because Colorado has more cosmic radiation at a higher altitude and more terrestrial radiation from soils enriched in naturally occurring uranium. Furthermore, a lot of our natural exposure is due to radon, a gas from the earth's crust that is present in the air we breathe.

About half of the total annual average U.S. individual’s radiation exposure comes from natural sources. The other half is mostly from diagnostic medical procedures. The average annual radiation exposure from natural sources is about 310 millirem (3.1 millisieverts or mSv). Radon and thoron gases account for two-thirds of this exposure, while cosmic, terrestrial, and internal radiation account for the remainder. No adverse health effects have been discerned from doses arising from these levels of natural radiation exposure.

Man-made sources of radiation from medical, commercial, and industrial activities contribute about another 310 mrem to our annual radiation exposure. One of the largest of these sources of exposure is computed tomography (CT) scans, which account for about 150 mrem. Other medical procedures together account for about another 150 mrem each year. In addition, some consumer products such as tobacco, fertilizer, welding rods, exit signs, luminous watch dials, and smoke detectors contribute about another 10 mrem to our annual radiation exposure.

The pie chart on the following page shows a breakdown of radiation sources that contribute to the average annual U.S. radiation dose of 620 mrem. Nearly three-fourths of this dose is split between radon/thoron gas and diagnostic medical procedures. Although there is a distinction between natural and man-made radiation, they both affect us in the same way.

Above background
levels of radiation
exposure, the NRC
requires that its
licensees limit
maximum radiation
exposure to individual
members of the public
to 100 mrem (1mSv)
per year, and limit
occupational radiation
exposure to adults
working with
radioactive material to
5,000 mrem (50 mSv)
per year. NRC
regulations and
radiation exposure limits are contained in Title 10 of the Code of Federal Regulations, Part 20.

Biological Effects of Radiation

We tend to think of biological effects of radiation in terms of their effect on living cells. For low levels of radiation exposure, the biological effects are so small they may not be detected. The body has repair mechanisms against damage induced by radiation as well as by chemical carcinogens. Consequently, biological effects of radiation on living cells may result in three outcomes: (1) injured or damaged cells repair themselves, resulting in no residual damage; (2) cells die, much like millions of body cells do every day, being replaced through normal biological processes; or (3) cells incorrectly repair themselves resulting in a biophysical change.

The associations between radiation exposure and the development of cancer are mostly based on populations exposed to relatively high levels of ionizing radiation (e.g., Japanese atomic bomb survivors, and recipients of selected diagnostic or therapeutic medical procedures). Cancers associated with high-dose exposure (greater than 50,000 mrem) include leukemia, breast, bladder, colon, liver, lung, esophagus, ovarian, multiple myeloma, and stomach cancers. Department of Health and Human Services literature also suggests a possible association between ionizing radiation exposure and prostate, nasal cavity/sinuses, pharyngeal and laryngeal, and pancreatic cancer.

The period of time between radiation exposure and the detection of cancer is known as the latent period and can be many years. Those cancers that may develop as a result of radiation exposure are indistinguishable from those that occur naturally or as a result of exposure to other carcinogens. Furthermore, National Cancer Institute literature indicates that other chemical and physical hazards and lifestyle factors (e.g., smoking, alcohol consumption, and diet) contribute significantly to many of these same diseases.

Although radiation may cause cancers at high doses and high dose rates, currently there are no data to establish unequivocally the occurrence of cancer following exposure to low doses and dose rates – below about 10,000 mrem (100 mSv).

Even so, the radiation protection community conservatively assumes that any amount of radiation may pose some risk for causing cancer and hereditary effect, and that the risk is higher for higher radiation exposures. A linear, no-threshold (LNT) dose response relationship is used to describe the relationship between radiation dose and the occurrence of cancer. This dose-response hypothesis suggests that any increase in dose, no matter how small, results in an incremental increase in risk. The LNT hypothesis is accepted by the NRC as a conservative model for determining radiation dose standards, recognizing that the model may over estimate radiation risk.

High radiation doses tend to kill cells, while low doses tend to damage or alter the genetic code (DNA) of irradiated cells. High doses can kill so many cells that tissues and organs are damaged immediately. This in turn may cause a rapid body response often called Acute Radiation Syndrome. The higher the radiation dose, the sooner the effects of radiation will appear, and the higher the probability of death. This syndrome was observed in many atomic bomb survivors in 1945 and emergency workers responding to the 1986 Chernobyl nuclear power plant accident. Approximately 134 plant workers and firefighters battling the fire at the Chernobyl power plant received high radiation doses – 80,000 to 1,600,000 mrem (800 to 16,000 mSv) – and suffered from acute radiation sickness. Of these, 28 died within the first three months from their radiation injuries. Two more patients died during the first days as a result of combined injuries from the fire and radiation.

Because radiation affects different people in different ways, it is not possible to indicate what dose is needed to be fatal. However, it is believed that 50% of a population would die within thirty days after receiving a dose of between 350,000 to 500,000 mrem (3500 to 5000 mSv) to the whole body, over a period ranging from a few minutes to a few hours. This would vary depending on the health of the individuals before the exposure and the medical care received after the exposure. These doses expose the whole body to radiation in a very short period of time (minutes to hours). Similar exposure of only parts of the body will likely lead to more localized effects, such as skin burns.

Conversely, low doses – less than 10,000 mrem (100 mSv) – spread out over long periods of time (years) don't cause an immediate problem to any body organ. The effects of low doses of radiation, if any, would occur at the cell level, and thus changes may not be observed for many years (usually 5-20 years) after exposure.

Genetic effects and the development of cancer are the primary health concerns attributed to radiation exposure. The likelihood of cancer occurring after radiation exposure is about five times greater than a genetic effect (e.g., increased still births, congenital abnormalities, infant mortality, childhood mortality, and decreased birth weight). Genetic effects are the result of a mutation produced in the reproductive cells of an exposed individual that are passed on to their offspring. These effects may appear in the exposed person's direct offspring, or may appear several generations later, depending on whether the altered genes are dominant or recessive.

Although radiation-induced genetic effects have been observed in laboratory animals (given very high doses of radiation), no evidence of genetic effects has been observed among the children born to atomic bomb survivors from Hiroshima and Nagasaki.

NRC regulations strictly limit the amount of radiation that can be emitted by a nuclear facility, such as a nuclear power plant. A 1991 study by the National Cancer Institute, “Cancer in Populations Living Near Nuclear Facilities,” concluded that there was no increased risk of death from cancer for people living in counties adjacent to U.S. nuclear facilities. At the NRC’s request, the National Academy of Sciences is currently engaged in a state-of-the-art update to the earlier study. The new study will examine cancer rates in communities around operating and decommissioned nuclear power plants, as well as nuclear fuel cycle facilities.

NIOSH Dose Reconstruction Process Under Fire

The Alliance of Nuclear Worker Advocacy Groups (ANWAG) has been involved with the Energy Employee Occupational Illness Compensation Program Act (EEOICPA) since its inception. Our members have monitored the implementation of the law by the responsible agencies, attended and spoke at public meetings, and have offered our concerns to those agencies, Congress, the Part E Ombudsman, and the press.

We have recently reviewed the July 2008 edition of the Health Physics Radiation Journal which is dedicated to the National Institute of Occupational Safety and Health Office of Compensation Analysis Support’s (NIOSH) scientific papers on their dose reconstruction program and wish to offer a few observations.

ANWAG finds it odd that the Journal did not present any opposing views, as one would expect to find. At the very least, you might have recruited a guest editorialist, as many other journals do in a similar situation, to balance the opposing points of view of NIOSH and its critics with respect to dose reconstruction methodology. That editorialist could have reviewed other systems of dose reconstruction such as those employed the Defense Threat Reduction Agency (DTRA) for the Atomic Veterans since the early 1990s. ORAU is the major contractor for both NIOSH and DTRA dose reconstruction programs [REF 1a]. Yet, NIOSH and DTRA have had major issues with each other scientific methodology [REF 1b,c] and your readers would benefit from knowing about that major interagency controversy within our government. Instead, your portrayal of the NIOSH dose reconstruction program is very one-sided.

One misconception we also see is that NIOSH and its contractor Oak Ridge Associated Universities (ORAU) developed the methodology alone. The authors of the papers recognized that they had input from the interested stakeholders and advocates, yet the submissions to your journal appear that NIOSH and ORAU alone were responsible for the procedures. This portrayal is not quite accurate. While Dr. Paul Zeimer, Chairman of the Advisory Board on Radiation and Worker Health (the Board), acknowledged that the Board has a contractor to assist them, ANWAG feels it is important to note the invaluable contribution made by that contractor, Sanford Cohen and Associates (SC & A). At the direction of the Board, SC & A reviewed the site profiles NIOSH and their contractor issued and reported several deficiencies. In fact, SC & A found and reported in their November 10, 2006 report 33 deficiencies in the Feed Materials Production Center (Fernald) site profile.

SC & A also made significant contributions to many of the scientific methodologies published and used by NIOSH. At the direction of the Board, SC & A would work with NIOSH and their contractor, ORAU, in developing the scientific calculations necessary to reconstruct dose.
The advocates and claimants often do not agree with the assumptions. However, we do feel it is necessary that SC & A be acknowledged for their participation.

The process of developing the site profiles and scientific methodology has been long and arduous and too long for the stakeholders. We have seen a protracted battle to have NIOSH accept documentation or oral histories from the workers and advocates. A case in point is the Special Exposure cohort petition for the Rocky Flats facility. A petitioner stated in the petition that NIOSH was using an incorrect particle size for plutonium. NIOSH, after two years of debate with the petitioners, the Board and the Board’s contractor, SC & A, finally agreed that the petitioners’ claim was correct and revised their methodology, as evidenced in their technical bulletin, ORAUT-OTIB-0049.

Another example of the length of time it takes NIOSH and its contractor to agree to a stakeholder’s assertion is the conflict of interest policy. The paper written by Judson L. Kenoyer, Edward D. Scalsky and Timothy D. Taulbee, employees of ORAU contractor, Dade Moeller and Associates, states, “However, care must be exercised to avoid selecting a Document Owner – or any other team member – who has worked at the specific site in the past; otherwise he or she will be considered by third-party reviewers as having a potential conflict of interest.” For the Rocky Flats facility, NIOSH and the Board were advised of the conflict with the author of the site profile by claimants and advocates in 2003. The author was not removed as an author until 2006. A similar conflict was presented to the Board and NIOSH concerning the Neutron Dose Reconstruction Project for the Rocky Flats plant. Unfortunately, that concern of the advocates with this conflict was ignored.

Town Hall-style Meeting May 3 for Former Metals & Controls and Texas Instruments Workers with U.S. Rep. Joseph Kennedy III and the U.S. Labor Department

ATTLEBORO - U.S. Rep. Joseph Kennedy III and the U.S. Labor Department will hold a town hall-style meeting May 3 for former Metals & Controls and Texas Instruments workers who became ill after working at the Forest Street industrial complex that once made nuclear fuel.

The meeting will be held from 6 to 8 p.m. at the Attleboro branch of Bristol Community College at the site of the former Metals & Controls plant.

Kennedy, D-Newton, will be present for the event, his office confirmed.

Thousands of factory workers labored at the industrial campus, which manufactured nuclear fuel for the Navy and other customers from 1952 to 1981.

Hundreds were diagnosed with cancer either while employed or after leaving jobs at the complex.

Although only a small part of the plant was used for nuclear manufacturing, the Attleboro site has been classified by the federal government as a former "atomic weapons employer."

Fuel manufactured at the site was used in nuclear submarines and government research reactors.

Texas Instruments, which conducted a major environmental cleanup of the site in the late 1990s, sold its Attleboro-based business in 2005. Many of the buildings have been converted to new uses for manufacturing, offices and to house branches of Bristol Community College and Bridgewater State University.

The Sun Chronicle documented in a series of reports that more than 300 former Metals & Controls and TI workers suffering from cancer received more than $30 million in payments and medical benefits under a special Labor Department program. The program is to compensate nuclear defense employees who became ill because of their work.

Some of the former plant workers interviewed by The Sun Chronicle reported contracting multiple cancers and having lost co-workers and family members who worked at the plant.

However, the newspaper found little was done to reach out to ex-employees - many of them senior citizens - to inform them how could get help with their cancers.

As a result, Kennedy raised the issue at a congressional hearing eliciting a pledge by Texas Instruments to reach out to its former workers.

The company later sent out more than 2,000 letters informing ex-employees how to apply under the government program.

A spokeswoman for Kennedy's office said the May 3 meeting is intended to provide information to the public and former atomic workers who believe they might have developed cancer as a consequence of their work. It will also include information about how and where to apply for compensation.

The meeting is also open to families with members who might have died or been affected by work-related cancer.

Other cold war sites in the Attleboro area and around Massachusetts were involved in nuclear weapons manufacturing during the 1950s and '60s, some of which remain contaminated with dangerous nuclear and chemical residue.

The former Engelhard Industries plant in Plainville made nuclear fuel for the Navy during the 1950s, but is still not fully decontaminated, although most traces of atomic residue were removed in the early '60s. The Environmental Protection Agency is supervising cleanup efforts, mostly involving chemical contamination.

The former D.E. Makepeace plant at the corner of Pine and Dunham Streets in Attleboro was also licensed during the 1950s to use uranium and other products associated with nuclear manufacturing. However the EPA was unable to find any indication of elevated radiation during detailed examinations of the site.

The former manufacturing plant has since been turned into housing for senior citizens.

who became ill after working at the Forest Street industrial complex that once made nuclear fuel.

The meeting will be held from 6 to 8 p.m. at the Attleboro branch of Bristol Community College at the site of the former Metals & Controls plant.

Kennedy, D-Newton, will be present for the event, his office confirmed.

Thousands of factory workers labored at the industrial campus, which manufactured nuclear fuel for the Navy and other customers from 1952 to 1981.

Hundreds were diagnosed with cancer either while employed or after leaving jobs at the complex.

Although only a small part of the plant was used for nuclear manufacturing, the Attleboro site has been classified by the federal government as a former "atomic weapons employer."

Fuel manufactured at the site was used in nuclear submarines and government research reactors.

Texas Instruments, which conducted a major environmental cleanup of the site in the late 1990s, sold its Attleboro-based business in 2005. Many of the buildings have been converted to new uses for manufacturing, offices and to house branches of Bristol Community College and Bridgewater State University.

The Sun Chronicle documented in a series of reports that more than 300 former Metals & Controls and TI workers suffering from cancer received more than $30 million in payments and medical benefits under a special Labor Department program. The program is to compensate nuclear defense employees who became ill because of their work.

Some of the former plant workers interviewed by The Sun Chronicle reported contracting multiple cancers and having lost co-workers and family members who worked at the plant.

However, the newspaper found little was done to reach out to ex-employees - many of them senior citizens - to inform them how could get help with their cancers.

As a result, Kennedy raised the issue at a congressional hearing eliciting a pledge by Texas Instruments to reach out to its former workers.

The company later sent out more than 2,000 letters informing ex-employees how to apply under the government program.

A spokeswoman for Kennedy's office said the May 3 meeting is intended to provide information to the public and former atomic workers who believe they might have developed cancer as a consequence of their work. It will also include information about how and where to apply for compensation.

The meeting is also open to families with members who might have died or been affected by work-related cancer.

Other cold war sites in the Attleboro area and around Massachusetts were involved in nuclear weapons manufacturing during the 1950s and '60s, some of which remain contaminated with dangerous nuclear and chemical residue.

The former Engelhard Industries plant in Plainville made nuclear fuel for the Navy during the 1950s, but is still not fully decontaminated, although most traces of atomic residue were removed in the early '60s. The Environmental Protection Agency is supervising cleanup efforts, mostly involving chemical contamination.

The former D.E. Makepeace plant at the corner of Pine and Dunham Streets in Attleboro was also licensed during the 1950s to use uranium and other products associated with nuclear manufacturing. However the EPA was unable to find any indication of elevated radiation during detailed examinations of the site.

The former manufacturing plant has since been turned into housing for senior citizens.

U.S. officials, Kennedy to meet on TI cancer rates

BY RICK FOSTER SUN CHRONICLE 

ATTLEBORO - U.S. Rep. Joseph Kennedy III and the U.S. Labor Department will hold a town hall-style meeting May 3 for former Metals & Controls and Texas Instruments workers who became ill after working at the Forest Street industrial complex that once made nuclear fuel.

The meeting will be held from 6 to 8 p.m. at the Attleboro branch of Bristol Community College at the site of the former Metals & Controls plant.

Kennedy, D-Newton, will be present for the event, his office confirmed.

Thousands of factory workers labored at the industrial campus, which manufactured nuclear fuel for the Navy and other customers from 1952 to 1981.

Hundreds were diagnosed with cancer either while employed or after leaving jobs at the complex.

Although only a small part of the plant was used for nuclear manufacturing, the Attleboro site has been classified by the federal government as a former "atomic weapons employer."

Fuel manufactured at the site was used in nuclear submarines and government research reactors.

Texas Instruments, which conducted a major environmental cleanup of the site in the late 1990s, sold its Attleboro-based business in 2005. Many of the buildings have been converted to new uses for manufacturing, offices and to house branches of Bristol Community College and Bridgewater State University.

The Sun Chronicle documented in a series of reports that more than 300 former Metals & Controls and TI workers suffering from cancer received more than $30 million in payments and medical benefits under a special Labor Department program. The program is to compensate nuclear defense employees who became ill because of their work.

Some of the former plant workers interviewed by The Sun Chronicle reported contracting multiple cancers and having lost co-workers and family members who worked at the plant.

However, the newspaper found little was done to reach out to ex-employees - many of them senior citizens - to inform them how could get help with their cancers.

As a result, Kennedy raised the issue at a congressional hearing eliciting a pledge by Texas Instruments to reach out to its former workers.

The company later sent out more than 2,000 letters informing ex-employees how to apply under the government program.

A spokeswoman for Kennedy's office said the May 3 meeting is intended to provide information to the public and former atomic workers who believe they might have developed cancer as a consequence of their work. It will also include information about how and where to apply for compensation.

The meeting is also open to families with members who might have died or been affected by work-related cancer.

Other cold war sites in the Attleboro area and around Massachusetts were involved in nuclear weapons manufacturing during the 1950s and '60s, some of which remain contaminated with dangerous nuclear and chemical residue.

The former Engelhard Industries plant in Plainville made nuclear fuel for the Navy during the 1950s, but is still not fully decontaminated, although most traces of atomic residue were removed in the early '60s. The Environmental Protection Agency is supervising cleanup efforts, mostly involving chemical contamination.

The former D.E. Makepeace plant at the corner of Pine and Dunham Streets in Attleboro was also licensed during the 1950s to use uranium and other products associated with nuclear manufacturing. However the EPA was unable to find any indication of elevated radiation during detailed examinations of the site.

The former manufacturing plant has since been turned into housing for senior citizens.