RADIOACTIVE CONTAMINATION AND POTENTIAL
Joseph J. Mangano,
This report was
prepared with the assistance of:
Oyster Creek is the oldest of 104 nuclear reactors operating in the U.S. The AmerGen Company has applied to the federal government to extend Oyster Creek’s license for an additional 20 years after it expires on April 9, 2009. To date, federal officials have not acknowledged any public health risks of operating Oyster Creek for 20 more years.
Exposure to radioactivity has been linked to numerous negative human health impacts, including cancer. Continuing to operate Oyster Creek increases the risk of human exposure to radioactivity in two basic ways.
First, continued operation would cause the reactor core to produce additional high-level radioactive waste that would be added to the 1,000 tons already stored at the site. Coupled with the growing local population, more stored radioactive waste would make the results of a meltdown from mechanical failure or act of sabotage even more severe than at present.
Second, nuclear plant operations routinely release radioactivity, both at refueling and on an on-going basis. Continued operation of the plant thus means more radioactivity release to the environment. Circumstantial evidence suggests Oyster Creek’s present operations may be having significant impacts on human health; that makes the increased risks of exposure from continued operation very troubling.
The principal findings of the report are:
1. Oyster Creek has emitted more radioactivity than most U.S. reactors. Depending on which type of radioactivity is measured, it ranks between 1st and 10th from 2001-2004.
2. Annual airborne emissions of radioactive Strontium-90 from Oyster Creek were higher in 1994-2004 than 1983-1993. The median annual release increased from 50 to 70 microcuries, and the number of major spikes in annual releases increased from 1 to 3.
3. Oyster Creek is not only old, it has been heavily used in recent years, operating 96% of the time in this decade, compared to just 67% before 1995. As a result of its age and wear and tear, parts of the reactor system have significantly corroded, increasing the chance of a catastrophic meltdown.
Circumstantial Evidence of Radioactive Contamination from Oyster Creek
4. Within the area measured, levels of radioactive isotopes that do not occure in nature but are produced in nuclear reactors are generally highest in water, fish, sediment, and vegetation closest to the Oyster Creek site.
5. The average level of radioactive Strontium-90 in New Jersey baby teeth, many from children living close to Oyster Creek, has doubled from the late 1980s to the late 1990s. Sr-90 is an isotope only produced by nuclear reactors and nuclear bombs.
Circumstantial Evidence Suggesting a Possible Link Between Oyster Creek and Cancer
6. Ocean County has the highest cancer incidence rate of any New Jersey county
7. The Ocean County death rate is above the U.S. for cancer, but below for other causes
8. A statistical link has been documented between trends in Strontium-90 in baby teeth and childhood cancer incidence in Monmouth and Ocean Counties. Five years after an increase or decrease in the Sr-90 levels occurs, a corresponding increase or decrease appears in childhood cancer incidence.
9. Elsewhere, the closing of nuclear power plants has been correlated with a decrease in cancer incidence. One of the most striking cases is the Rancho Seco, California plant. Immediately after that plant closed, cancer started decreasing in the four counties downwind of the plant. If closing Oyster Creek were correlated with a similar cancer decrease, it could mean 4810 fewer cancer deaths over 20 years in Monmouth and Ocean Counties.
Produced in Reactors
These radioactive chemicals, which are gases and particles, include Cesium-137, Iodine-131, and Strontium-90. They are highly unstable atoms which emit alpha particles, beta particles, or gamma rays. When they enter the body, they affect various organs. Cesium seeks out the muscles (including the heart), iodine attacks the thyroid gland, and strontium travels to the bone. Each causes cancer after damaging DNA in cells and creating mutations, and is especially harmful to the fetus, infant, and child. Some decay quickly (Iodine-131 has a half life of eight days), while others remain for long periods (Strontium-90 = 29 years).
Most of the radioactivity in reactors is contained within the reactor building and stored as high-level waste in deep pools of water that must be constantly cooled. At Oyster Creek and elsewhere, the pools are full, and some waste has been transferred to above-ground outdoor casks. Oyster Creek currently holds approximately 1000 tons of waste on site, and additional radioactivity in the reactor’s core. The amount of radioactivity stored at Oyster Creek is equivalent to several Chernobyls, and hundreds of Hiroshima bombs. Continued operation of Oyster Creek will result in more high-level waste stored in outdoor casks, as the waste has nowhere else to go.
The federal government has designated Yucca Mountain in Nevada as a permanent waste site. Yucca has encountered much opposition, and will not open in the foreseeable future. Many experts believe no permanent repository will ever open, leaving existing nuclear plants to maintain the waste indefinitely.
B. Health Hazards Posed by Reactor Meltdown
Much of the health concern from nuclear reactors is on effects of a major meltdown. The radioactivity in a reactor core and waste pools must be constantly cooled by water, or the red-hot fuel will melt, causing a huge radioactivity release. This meltdown scenario can be caused by an accidental mechanical failure, such as at Chernobyl, or by a deliberate act of sabotage on the order of the 9/11 attacks.
Oyster Creek is perhaps more vulnerable to terrorist attack than most other reactors, for three reasons. First, its proximity to large population centers including New York City and Philadelphia may make it an unusually attractive target. Second, it is a boiling water reactor of an obsolete design, and would be less able to contain radioactivity released from its core. Third, because of its location on the ocean, it would be possible to attack the reactor by sea, in addition to air and land. The State of New Jersey is very concerned about the terrorism risk, and is involved in litigation to force the U.S. Nuclear Regulatory Commission to consider the risk in its re-licensing decision.
Whether caused by accidental failure or deliberate attack, the health consequences of a major meltdown at Oyster Creek would be catastrophic, both because of the nearby population centers and the volume of radioactive material at the site. The 1986 Chernobyl experience is instructive. A variety of journal articles and other reports have documented that the Chernobyl meltdown resulted in elevated levels of cancer, birth defects, and other immune disorders, in the former Soviet Union and throughout Europe.
C. Routine Emissions from Oyster Creek
Catastrophic meltdowns are not the only way nuclear plants release radiation. All nuclear reactors must routinely emit radioactivity into the environment in order to operate. There are several types of releases. One is accidental releases due to leaking equipment, which can include the cladding and welds of fuel rods in the reactor core, cracks and breaks in fuel that damages cladding, corroding pipes, and cracked steam generator tubes. In this way, some radioactivity is released into air, and some into water. Radioactivity is also deliberately released into local water about every 18 months when reactors refuel.
Oyster Creek has historically had relatively high environmental emissions. By one measure*, it has the second highest emissions of any U.S. nuclear plant (Table 1). The four plants with the highest emission levels operate Boiling Water Reactors (as opposed to Pressurized Water Reactors).
In recent years, emissions from Oyster Creek have continued to be much greater than most U.S. reactors for various forms of airborne releases. From 2001-2004, Oyster Creek was 10th highest in fission product emissions, 5th highest in iodine, 2nd highest in Strontium-90, and 1st highest in Strontium-89.
Strontium-90 emissions are of particular interest. Although the New Jersey Department of Environmental Protection issued a report to Governor Jon Corzine in January 2006 on Oyster Creek and Strontium-90, concluding that levels have been declining over time, closer examination shows emissions are rising, the median annual release from 1983-1993 was 50 microcuries, but from 1994-2004 it was 70. In addition, 1983-1993 saw only one year with a large spike in radioactive releases (350 microcuries in 1985), but from 1994-2004, three years had major spikes: 600 microcuries in 2001, 1000 microcuries in 1997, and 4000 microcuries in 1994. This trend of increasing releases is troubling and may indicate greater emissions from an aging nuclear reactor.
D. Environmental Levels of Radioactivity Near Oyster Creek
Nuclear reactor operators are mandated to make periodic measurements of radioactivity levels in the air, water, and food, and report this information to the federal government. Various environmental radioactivity levels are given in the annual Environmental Operating Report prepared by each nuclear reactor operator. In 2005, the most recent report for Oyster Creek, data for environmental levels in water, fish, sediment, and vegetation are presented – at locations near to and distant from Oyster Creek. In some, there is little or no difference regardless of location; but for 16 measures, there is at least a 45% difference (Table 2).
In 12 of 16 instances, the higher number is the location close to the plant. In 3 of the 4 cases where the distant location had a higher level, potassium-40 was measured. This chemical is found in nature, not just in nuclear reactors and weapons. All other chemicals in the table represent man-made fission products.
The only man-made product in which higher levels were detected further from the plant is Strontium-90. While there is no clear explanation for this, it is important to place more emphasis on general patterns, rather than exceptions. In addition, conducting a multi-year analysis on patterns and trends of environmental levels would be helpful.
E. In-Body Levels of Radioactivity Near Oyster Creek
The question of how much man-made radioactivity actually enters the body was first considered in the 1950s, when scientists studied Strontium-90, one of the 100-plus chemicals in bomb fallout and nuclear reactor emissions. Two government-sponsored programs (one for adults, one for children) measured Sr-90 levels in bone.
A landmark study of St. Louis baby teeth showed that the average Sr-90 level for children born in 1964, as the test ban was enacted, was 50 times greater than that of children born in 1950, before bomb testing. The average declined by about half in the six years after testing ended. Comprehensive results were published by Harold Rosenthal of Washington University, the study’s lab director, in the Proceedings of the 1969 Hanford Radiobiological Symposium in Richland WA.
There were no studies measuring in-body radioactivity levels for Americans near reactors until 1996, when the Radiation and Public Health Project (RPHP) research organization recognized the lack of such information, and began the Tooth Fairy Project. The work was patterned on the earlier St. Louis study, measuring Sr-90 levels in baby teeth. RPHP purchased a machine designed to measure low dose radioactivity levels, selected the REMS radiochemistry lab of Waterloo, Ontario, Canada to do the testing, and established protocols for tooth testing.
The lab calculated the ratio of Strontium-90 to calcium, and RPHP converted it to a ratio at birth, using the half life of 28.7 years. (Most Sr-90 in a baby tooth is taken up during pregnancy and the first few months of life). If a tooth from a person age 28.7 years has a current ratio of 4.30, the ratio at birth would be 8.60. Teeth were classified according to where the mother lived during pregnancy and first year of life, not the current address.
RPHP has tested nearly 5,000 teeth (over 500 from New Jersey), and published five medical journal articles on results. The most comprehensive results of the study, from the article “An Unexpected Rise in Strontium-90 in US Deciduous Teeth in the 1990s” published in the 2003 Science of the Total Environment found that average Sr-90 in baby teeth were highest in counties closest to seven nuclear plants, and that averages rose sharply since the late 1980s, as reactors aged and operated more frequently.
New Jersey results were consistent with those in other states. From 1975 to 1989, average Sr-90 levels in teeth declined, most likely due to the decay of left-over fallout from atomic bomb tests. But after 1989, the Sr-90 levels increased. Indeed, children born to parents residing in New Jersey during 1996-1998, the most recent data available, had a Sr-90 level 100% greater than those born in 1987-1989, and only 7% less than the 1975-1977 levels (Figure 1). Over two thirds of these teeth are from children living in Ocean and Monmouth Counties, the closest counties downwind from Oyster Creek, with the great majority from Ocean County.
This rapid and steady increase can only be due to a current source of radioactivity, which makes changes in levels of old bomb test fallout (tests ended in 1963), nuclear weapons reactors (which virtually ceased operation by 1990) or Chernobyl fallout (a one-time event in 1986) highly unlikely. The only source that currently produces Sr-90 on a large scale is nuclear reactors such as Oyster Creek.
F. Potential Health Risks to Residents Near Oyster Creek
The population in the area near Oyster Creek has grown rapidly throughout the 20th century, as more people moved away from urban areas and to coastal communities. About 4.2 million persons now live within 50 miles of the reactor, including greater Philadelphia. Perhaps most at risk are residents of Ocean and Monmouth Counties. All residents of these two counties live within 40 miles of the plant, and to the north (which is downwind, as prevailing coastal breezes originate from the south).
The two counties had a total population of just 100,000 in 1900, and 200,000 by 1940. But a sustained growth occurred thereafter until the current total reached over 1.2 million, and will exceed 1.5 million by 2025, according to U.S. Census Bureau projections. The large population growth means a larger market for electricity. It also means that more are exposed to harmful radioactivity from Oyster Creek.
Monmouth and Ocean Counties have none of the classic risk factors for health problems. The percent of minorities, who tend to have higher disease rates, are well below state and national levels. A smaller portion of persons who are foreign born, do not speak English, are poor, or who didn’t complete high school means fewer language barriers to good health practices and fewer obstacles to accessing health services. And yet cancer is unusually prevalent in Ocean County.
National Cancer Institute Study. There has been only one federal study of disease rates near U.S. nuclear power plants. The National Cancer Institute examined local cancer mortality before and after the startup of 62 U.S. nuclear plants, from 1950-1984. NCI data show that Ocean County cancer mortality increased more rapidly than the U.S. rate for most types of cancer after Oyster Creek started (Table 3).
The National Cancer Institute study provided some helpful information, but just begins to address the question of cancer risk near Oyster Creek. It only used data prior to 1985, and was limited to Ocean County. Furthermore, it only included cancer deaths, not cases, as a reliable state cancer registry did not exist prior to the late 1970s.
Cancer Incidence. The New Jersey Cancer Registry now publishes cancer incidence data by county. In 1999-2003, Ocean County had the highest cancer incidence rate of all New Jersey counties, a rate 19% above the U.S. mark. Monmouth County has the 5th highest rate (Table 4). For whites, Ocean and Monmouth have the two highest cancer incidence rates of all counties in the state. Ocean County has the lowest rate of any county for blacks – although blacks account for only 3% of the population. Nearly 8,000 local residents are diagnosed with cancer each year.
Cancer incidence among local children is an important indicator of whether radioactive emissions from Oyster Creek have harmed local public health, as the fetus and young infant are especially susceptible to radiation exposure. From 1985-2003 there were 285 Monmouth and 225 Ocean County children under age ten diagnosed with cancer, a rate that exceeded the rest of the state by 16.1% and 9.3%, respectively (19.33 and 18.20 vs. 16.65 cases per 100,000 population). The local rate for most of the 20-year period was 21.6% greater than the U.S. rate of 15.59 per 100,000.
Cancer Mortality. Along with incidence, cancer mortality is unusually high in Monmouth and Ocean Counties, even though both counties are below the U.S. rate for all causes except cancer. This divergence is especially large for children. The 1985-2003 cancer death rate for Monmouth and Ocean County children under age 15 is 13.4% above the U.S., while the rate for other causes under age 15 is 31.7% below the nation. Data is from the U.S. Centers for Disease Control and Prevention web site.
This pattern is consistent for breast cancer. The Monmouth and Ocean County breast cancer death rate in the past two decades was 20.1% above the U.S., but 4.5% below for all causes other than cancer (Table 5). These differences are consistent for young, middle-aged, and older women.
The five most common causes of death (circulatory
disease, cancer, respiratory disease, accidents/suicide/homicide, and
nervous system diseases) account for about 83% of all death nationally.
In the period 1999-2003, the Ocean/Monmouth death rate falls below the
U.S. for four of these five categories, an expected result because of
the lack of obvious demographic risk factors. The exception is cancer,
the rate of which has been above the U.S. for decades (Figure 2).
Thyroid cancer is the fastest-rising cancer
in the U.S., more than doubling since 1980. New Jersey has the second
highest rate of thyroid cancer incidence, adjusted for the 2000 U.S. standard
population, of 39 U.S. states from 2000-2002, trailing only Pennsylvania.
Its rate of 10.14 per 100,000 persons is 32% higher than the U.S. rate.
The large number of cases (2665), and the known link between radioiodine
and thyroid cancer, raises the question of whether Oyster Creek (and other
nuclear reactors) have contributed to this elevated rate.
G. Potential Radiation/Cancer Link
RPHP compared trends in Sr-90 in baby teeth with trends in childhood cancer incidence. Figure 3 is a line graph for each trend in Monmouth and Ocean County for a 14 year period. When the Sr-90 level rises, cancer incidence in children under age ten also rises, and conversely declines in Sr-90 are followed by declines in cancer incidence. There is a five year lag period, meaning changes in Sr-90 are followed by the same changes for childhood cancer five years later. This finding was published in a 2006 article in the International Journal of Health Services.
This article documented that the link is statistically significant at p <.05 using a Poisson regression test, as hundreds of teeth and cancer cases are used in the analysis. It is also broadly consistent with other scientific research, such as Dr. Alice Stewart’s discovery in the 1956 Lancet that fetuses of mothers who were given pelvic X-rays were twice as likely to die of cancer by age ten, which led to a cessation of this practice to pregnant women.
RPHP also investigated whether Sr-90 in teeth was linked with childhood cancer by using teeth from children with cancer. Backed by a $25,000 grant from the New Jersey state legislature and tooth donations from the Deirdre Imus Environmental Center for Pediatric Oncology at Hackensack Medical Center, RPHP received 52 teeth from New Jersey children with cancer. Only 31 could be analyzed, as some were not properly labeled, some were from children whose parents lived out of state at birth, and some had too little healthy enamel to be accurately tested.
The comparison of average Sr-90 in teeth for children with and without cancer was hampered by small sample sizes, and any differences between the two groups were not meaningful. RPHP plans to conduct additional studies to enhance this analysis.
Overall, RPHP produced considerable evidence that Sr-90 in baby teeth is statistically linked with risk of childhood cancer, suggesting further research would be helpful in better understanding this relationship.
It is important to note that Sr-90 in just one of over 100 radioactive chemicals that enters the body from nuclear reactors. Thus, it is prudent to assert that any link between Sr-90 and cancer does not designate Sr-90 as the singular cause of cancer. Rather, Sr-90 should be regarded as a marker for the full array of long-lived radioactive chemicals. It would be quite helpful similar studies of isotopes other than Sr-90 were conducted.
Exposure to radiation is just one of many
potential causes accounting for the unexpectedly elevated cancer rates
in Ocean County. Even among environmental factors, there are many other
alternatives to consider. For example, there are at least 18 toxic waste
disposal sites in the county. While the process of understanding relative
contributions among risk factors is often difficult, the high cancer rates
in Ocean County – especially those that are radiosensitive –
and the statistical connection between childhood cancer and Sr-90 in baby
teeth mean that Oyster Creek emissions must be taken seriously as one
potential factor in any subsequent analyses.
H. Potential Health Improvements of Closing Oyster Creek.
Precedent – Atomic Bomb Test Halt. If Oyster Creek closes at the end of its 40 year license in April 2009, no additional radioactivity will be produced or released from the reactor core (the radioactive waste in indoor pools and outdoor casks will remain). Closing the reactor will reduce levels of these products in the environment and body. There is a precedent for such reductions. When above ground atomic bomb tests ceased after the Partial Test Ban Treaty of 1963, chemicals that decay quickly (such as Iodine-131, with a half life of eight days) virtually disappeared. Chemicals with a slower decay rate also dropped; Strontium-90 fell 75% in milk and 50% in bones from 1964-1970, according to studies conducted by the U.S. Public Health Service.
Reduced environmental radioactivity raises the question of whether disease rates would also decline, especially among the more susceptible infants and children. Again, there may be precedent for such a change. The incidence of cancer age 0-4 in Connecticut, the only state which kept such records in the 1960s, rose rapidly as large-scale bomb testing continued; from 1959 to 1962, incident cases increased from 41 to 60. But after testing ended, the number of cases plunged. From 60 cases in 1962, annual totals dropped to just 30 in 1968 (Table 6). Cancer incidence age 0-4 can be seen as one of the most reliable indicators of harm from radiation exposure, as these cancers often represent outcomes of an insult to the fetus, which is most sensitive to radiation exposure.
Precedent – Nuclear Reactor Closing. In addition to reduced disease and death rates after atomic bomb test cessation, there may be a precedent for reductions after nuclear reactors close and radioactive releases end. A 2002 journal article by the Radiation and Public Health Project entitled “Infant Death and Childhood Cancer Reductions After Nuclear Plant Closings in the United States” was published in the Archives of Environmental Health. The paper examined reactors that closed from 1987-1998 that were at least 70 miles from any other reactor.
The article compared cancer incidence in children under age five in the two years prior to reactor closing (year of closing and year before) with the 2-7 year period after closing (depending on the available data at the time). For areas near six closed reactors, the rate fell each time (total of -24.8%), even though nationwide there was a slight increase in childhood cancer during this period.
Cancer reductions for people of all ages have also occurred near closed nuclear reactors. For example, the Rancho Seco reactor in Sacramento County CA closed on June 6, 1989. The four California counties within 40 miles downwind (east) of Rancho Seco have a population of 1.9 million. Compared to the U.S., the area has roughly the same percentage of blacks and Hispanics (24.3% vs. 27.2%), foreign born residents (13.7% vs. 11.1%), educational levels (25.6% vs. 24.4% of adults who are college graduates), and poverty levels (11.7% vs. 12.5%).
In the 1980s, while Rancho Seco was operating, the local cancer death rate was higher than the U.S. But in the 1990s and 2000s, after shutdown, levels abruptly moved below the U.S. The difference between the actual (lower) cancer death rates and a continuation of previous rates equals 3225 fewer local cancer deaths from 1990-2003.
Reductions in cancer after reactor closing (especially with little or no latency period) may reflect various contributing factors, including effects of reduced exposure to radioactivity. However, no definitive explanation for this consistent trend is apparent.
Potential Cancer Reduction After Oyster Creek Closing. To the extent, if any, that Ocean and Monmouth Counties’ elevated cancer rates are caused by Oyster Creek’s radioactive releases, closing Oyster Creek could result in a decrease in cancer incidence and cancer mortality. If cancer death rates in Ocean and Monmouth Counties - within 40 miles and downwind from Oyster Creek - declined at a similar rate as in the four counties near the closed Rancho Seco reactor, the reduction in cancer deaths from 2009 to 2029 would be 4,810. The great majority of these would be adults, as cancer mortality in children is much lower than for adults.
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