March 15, 2007
Mayor Sam LaGrone
City Hall
425 N. Richardson
Roswell, NM 88201
Dear Mayor LaGrone:
Please review the following, today, so that our meeting may be more productive.
A few days ago, I read an article on the Internet that said: "Roswell's mayor says relying on foreign oil is dangerous, and the nation needs nuclear power. The article doesn't come right out and say whether or not you believe it would be good to have the proposed nuclear waste reprocessing plant near Roswell. I am deeply concerned that you may be deceived and misled into believing it would be good for Roswell as it appears that some in New Mexico's legislature, and some of New Mexico's US Representatives and Senators have been deceived and misled into believing it would be good for New Mexico. With this in mind, I am giving you the following information.
First, as long as I have known you, I have believed you to be a good person with good intentions, and that you have a genuine sense of responsibility toward the betterment of Roswell. If you have been deceived and misled into believing that this nuclear waste reprocessing plant would be good for Roswell, please do not perceive this information as being a personal attack. It is given to you for the sole purpose of helping you mitigate the damage that this nuclear waste reprocessing plant would bring to Roswell.
When I was a kid, growing up here, I listened to grownups express their concerns about how dangerous the WIPP site near Carlsbad would be for southeastern New Mexico, and how dangerous it would be to have nuclear waste from all over the country transported through Roswell. I believed that grownups would figure out a way to keep Roswell safe as I left for a 12 year journey into higher education. I was still unpacking after returning to Roswell as I watched the first truck load of nuclear waste come through on its way to the WIPP site. At that point, I believed that our leaders in Washington, DC had seen enough nuclear disasters to close down all nuclear plants, and that the WIPP site was an unfortunate consequence of the "historical" Nuclear Age. Since then, I have been surprised on the rare occasion of hearing about a nuclear plant still operating somewhere in the United States. On these rare occasions, I have felt sure that it wouldn't be long before all nuclear plants would be closed down. If it weren't for my need to study the current status of nuclear energy to protect Roswell and the rest of southeastern New Mexico from the danger of this proposed nuclear waste reprocessing plant, I would have likely not become aware of how deceived and misled our leaders in Washington, DC have been.
Regarding your statement: "...relying on foreign oil is dangerous, and the nation needs nuclear power," I can understand how you may have been caught up in the excitement of the propaganda provided to you by the Department of Energy (DOE) and the nuclear industry, and how it may have put you in an environment where it seemed like this would be the appropriate thing to say. But I can assure you that the people, who made you feel this way, care very little about the health, safety, and welfare of people living in Roswell. Nuclear energy is likely the most dangerous kind of energy that there is. When it is used for producing electricity, it is highly profitable for a few at the expense of many. I hope that it isn't necessary to explain to you how sinister and detrimental to world peace it is to threaten to use nuclear weapons against other countries. As far as our nation becoming independent of foreign oil is concerned, there are many safer forms of alternative energy, including Hydrogen power, solar power, and wind power. The jury is still out on Ethanol, but I have a strong feeling that it will show itself to be safer than nuclear energy.
I know that the promise of jobs at the proposed nuclear waste reprocessing plant sounds like a good thing. I have spent the past 4 1/2 years studying the effects that a large chemical plant has had on a community in Arkansas where my father built a summer camp for kids from Roswell. I have learned a lot about how large corporations, which have polluted (subjected communities to unhealthy levels of toxic chemicals), have deceived the people living in the communities where they polluted. Part of this deception has been continuous talk about how much this polluting corporation benefits the community's economy. Kids, right out of high school, regardless of whether or not they have actually graduated, have been given jobs that paid wages that compared to wages of jobs requiring college degrees. But 15 to 25 years later, these same kids have started learning about the health effects of the toxic chemicals that they have been handling. I could continue by describing situations where these same kids have learned that there is actually a difference between workers compensation and disability checks, and that their disability check should actually be workers compensation, and by describing how employees at state and federal environmental and health agencies have explained how they would lose their jobs if they were caught telling the truth. But my current focus is on giving you information that will help you mitigate the damage that would be done to Roswell from a nuclear waste reprocessing plant.
During the past few days, I have done some research on the company that would be running the proposed nuclear waste reprocessing plant. This company used to be called Envirocare. It is now called EnergySolutions. I have found some interesting information about this company on the Internet. It appears that this company is good at disregarding the law. I have submitted a Freedom of Information Act request to the Utah Department of Environmental Quality for a list that will give a short description of each time this company has violated laws and regulations as far back as 1999. I was told that this list will be long. This company has been operating in Utah since 1989. Records of violations prior to 1999 have been archived, and would take a long time to obtain. I hope to have the list that covers from 1999 to 2007 with me when I visit with you in your office tomorrow morning.
I have talked with several people at the United States Environmental Protection Agency ( US EPA), the New Mexico Environment Department, and the Nuclear Regulatory Commission (NRC) to find out who would be inspecting this nuclear waste reprocessing plant with authority to enforce environmental laws. After listening to several opinions, it appears that the proposed nuclear waste reprocessing plant would belong to the Department of Energy and the Department of Defense, while the US EPA and the NRC would have no authority to enforce the law at this site. The only authority that the New Mexico Environment Department would have would be to monitor ambient releases of radioactivity and other pollution outside of the proposed nuclear waste reprocessing plant. And this site would be managed by a company with a history of being good at disregarding the law. You received a copy of the Email message that I sent to Tim Frazier in the Department of Energy Office of Nuclear Power, dated March 13.
I have read enough to understand that for more than 25 years EnergySolutions has disregarded the law, paid a fine without argument when they were caught, continued operations in the same sloppy and illegal way until the next inspection when they were caught again, paid the fine without argument, continued operations in the same sloppy and illegal way until they were caught again, and so on... They were even caught bribing the inspector in 1997. With this in mind, considering the way the proposed nuclear waste reprocessing plant would be regulated, it looks like EnergySolutions wouldn't have to worry anymore about getting caught breaking the law or paying fines.
According to an engineer, it is, theoretically, possible to reprocess nuclear waste with almost no chance for it to leak. It would involve having expensive backup system on backup system on backup system on containment system on containment system on containment system.
I have a strong feeling that the Mayors of Dallas, New York City, and Washington, DC have not considered taking a million dollars to do a feasibility study for having a nuclear waste reprocessing plant. I don't know exactly how Roswell became one of the communities involved in these feasibilities studies. But I am speculating that the Department of Energy has approached you, or our County Commissioners, because they perceive the population of Roswell and the rest of southeastern New Mexico as being impoverished, uneducated, and disposable.
I have observed a practice in the chemical industry called "Risk Reward Relationship." They measure the dollar value of human lives that could be affected by mishaps. Then they base their budget on safety on this dollar value of human lives. If they didn't expect it to leak, they would put it someplace like Downtown Dallas.
There is a web site that an EPA toxicologist introduced me to: http://toxnet.nlm.nih.gov/. It will be helpful in learning about the kinds of health problems we would need to prepare for in Roswell if we have the nuclear waste reprocessing plant. Below are 2 records that contain all of the query terms "nuclear waste reprocessing plant" in the same section. Please glance through this information.
Sincerely,
Frank McKinnon
903 N.Missouri
Roswell, NM 88201
office phone (505) 627-3391
cell phone (505) 420-2291
| 1 | NEPTUNIUM,
RADIOACTIVE NO CAS RN |
|
| 2 | PLUTONIUM,
RADIOACTIVE NO CAS RN |
The following information comes from these 2 records.
NEPTUNIUM, RADIOACTIVE
Human Toxicity Excerpts:
/OTHER TOXICITY INFORMATION/ In the nuclear
fuel cycle the transuranic radionuclides plutonium-239, americium-241 and
neptunium-237 would probably present the most serious hazard to human health if
released into the environment. ... The principal late effects of all three
radionuclides are the induction of cancers of bone, lung or liver. For the
latter tumors the induction risk per unit radiation dose appears similar for the
three radionuclides. But in bone there are indications that, due to microscopic
differences in the distribution of the alpha-particle radiation dose, the
efficiency of bone cancer induction may increase in the order americium-241 less
than plutonium-239 less than neptunium-237. No case of human cancer induced by
these radionuclides is known. /Plutonium-239, americium-241 and neptunium-237/
/OTHER TOXICITY INFORMATION/ LIFETIME CANCER MORTALITY RISK. Risks are for
lifetime cancer mortality per unit intake (pCi) averaged over all ages and both
genders. /Neptunium isotopes/
| ISOTOPE | Inhalation (pCi-1) | Ingestion (pCi-1) |
|---|---|---|
| Neptunium-235 | 1.0x10-12 | 2.8x10-13 |
| Neptunium-236 | 2.6x10-9 | 1.5x10-11 |
| Neptunium-237 | 1.5x10-8 | 5.8x10-11 |
Antidote and Emergency Treatment:
Basic Treatment. Establish a patent airway (oropharyngeal or nasopharyngeal
airway, if needed). Suction if necessary. Watch for signs of respiratory
insufficiency and assist ventilations if necessary. Administer oxygen by
nonrebreather mask at 10 to 15 mL/min. Monitor for shock and treat if necessary.
Anticipate seizures and treat if necessary. Perform routine emergency care for
associated injuries. ... Perform routine basic life support care as necessary. /Radioactives
I, II, and III/
Advanced Treatment. Consider orotracheal or nasotracheal intubation for airway
control in the patient who is unconscious or is in severe respiratory distress.
Monitor cardiac rhythm and treat arrhythmias as necessary. Start IV
administration of 0.9% saline (NS) or lactated Ringer's (LR) TKO. For
hypotension with signs of hypovolemia, administer fluid cautiously. Watch for
signs of fluid overload. Treat seizures with diazepam or lorazepam. Perform
routine advanced life support care as needed. Use proparacaine hydrochloride to
assist eye irrigation. /Radioactives I, II, and III/
CONTRAINDICATIONS Ca-DTPA is contraindicated for minors, pregnant women,
patients with the nephrotic syndrome, and in patients with bone marrow
depression. (Such patients may be treated with Zn-DTPA.) Ca-DTPA should not to
be used as a chelator for uranium or neptunium. Internal contamination with
uranium is currently treated by alkalizing the urine with bicarbonate in order
to promote excretion. DTPA has also been postulated to form an unstable complex
with neptunium, which may increase bone deposition of this actinide.
CONTRAINDICATIONS Ca-DTPA is contraindicated for minors, pregnant women,
patients with the nephrotic syndrome, and in patients with bone marrow
depression. (Such patients may be treated with Zn-DTPA.) Ca-DTPA should not to
be used as a chelator for uranium or neptunium. Internal contamination with
uranium is currently treated by alkalizing the urine with bicarbonate in order
to promote excretion. DTPA has also been postulated to form an unstable complex
with neptunium, which may increase bone deposition of this actinide.
Special Considerations. Most symptoms from radioactive product exposure are
delayed; treat other medical or trauma problems according to normal protocols.
An accurate history of the exposure is essential to determine risk and proper
treatment modalities. The dose of radiation determines the type and clinical
course of exposure: 100 rads: GI symptoms (nausea, vomiting, abdominal cramps,
diarrhea). Symptom onset within a few hours. 600 rads: Several GI symptoms
(necrotic gastroenteritis) may result in dehydration and death within a few
days. Several thousand rads: neurological/cardiovascular symptoms (confusion,
lethargy, ataxia, seizures, coma, cardiovascular collapse) within minutes to
hours. Bone marrow depression, leukopenia, and infections usually follow severe
exposures./Radioactives I, II, and III/
Emergency and supportive measures. Depending on the risk to rescuers, treatment
of serious medical problems takes precedence over radiologic concerns. If there
is a potential for contamination of rescuers and equipment, appropriate
radiation response protocols should be implemented, and rescuers should wear
protective clothing and respirators. Note: I the exposure was to electromagnetic
radiation only, the victim is not contaminating and does not pose a risk to
downstream personnel. 1. Maintain an open airway and assist ventilation if
necessary. 2. Treat coma and seizures if they occur. 3. Replace fluid losses
from gastroenteritis with iv crystalloid solutions. 4. Treat leukopenia and
resulting infections as needed. Immunosuppressed patients require reverse
isolation and appropriate broad-spectrum antibiotic therapy. Bone marrow
stimulants may help selected patients. /Radiation (Ionizing)/
Decontamination. 1. Exposure to particle-emitting solids or liquids. The victim
is potentially highly contaminating to rescuers, transport vehicles, and
attending health personnel. 1. Remove victims from exposure, and if their
conditions permit, remove all contaminated clothing and wash the victims with
soap and water. b. All clothing and cleansing water must be saved, evaluated for
radioactivity, and properly disposed of. c. Rescuers should wear protective
clothing and respiratory gear to avoid contamination. At the hospital, measures
must be taken to prevent contamination of facilities and personnel. d. Induce
vomiting or perform gastric lavage if radioactive material has been ingested.
Administer activated charcoal, although its effectiveness is unknown. Certain
other adsorbent materials may also be effective. e. Contact Radiation Emergency
Assistance Center & Training Site (REAC/TS/: telephone (865) 576-3131 or
(865) 481-1000)/ and the state radiologic health department for further advice.
In some exposures, unusually aggressive steps may be needed (eg, lung lavage for
significant inhalation of plutonium). 2. Electromagnetic radiation exposure. The
patient is not radioactive and does not pose a contamination threat. There is no
need for decontamination once the patient has been removed from the source of
exposure, unless electromagnetic radiation emitter fragments are embedded in
body tissues. /Radiation (Ionizing)/
Animal Toxicity Studies:
Evidence for Carcinogenicity:
Evaluation. There is inadequate evidence in humans for the carcinogenicity of
neutrons. There is sufficient evidence in experimental animals for the
carcinogenicity of neutrons. Overall evaluation. Neutrons are carcinogenic to
humans (Group 1). In making the overall evaluation, the Working Group took into
consideration the following: When interacting with biological material, fission
neutrons generate protons, and the higher-energy neutrons used in therapy
generate protons and alpha particles. Alpha Particle-emitting radionuclides
(e.g. radon) are known to be human carcinogens. The linear energy transfer of
protons overlaps with that of the lower-energy electrons produced by
gamma-radiation. Neutron interactions also generate gamma-radiation, which is a
human carcinogen. Gross chromosomal aberrations (including rings, dicentrics and
acentric fragments) and numerical chromosomal aberrations are induced in the
lymphocytes of people exposed to neutrons. The spectrum of DNA damage induced by
neutrons is similar to that induced by X-radiation but contains relatively more
of the serious (i.e. less readily repairable) types. Every relevant biological
effect of gamma- or X-radiation that has been examined has been found to be
induced by neutrons. Neutrons are several times more effective than X- and
gamma-radiation in inducing neoplastic cell transformation, mutation in vitro,
germ-cell mutation in vivo, chromosomal aberrations in vivo and in vitro and
cancer in experimental animals.
Internalized radionuclides that emit alpha-particles are carcinogenic to humans
(Group 1). In making this overall evaluation, the Working Group took into
consideration the following: (1) Alpha-Particles emitted by radionuclides,
irrespective of their source, produce the same pattern of secondary ionizations
and the same pattern of localized damage to biological molecules, including DNA.
These effects, observed in vitro, include DNA double-strand breaks, chromosomal
aberrations, gene mutations and cell transformation. (2) All radionuclides that
emit alpha-particles and that have been adequately studied, including radon-222
and its decay products, have been shown to cause cancer in humans and in
experimental animals. (3) Alpha-Particles emitted by radionuclides, irrespective
of their source, have been shown to cause chromosomal aberrations in circulating
lymphocytes and gene mutations in humans in vivo. (4) The evidence from studies
in humans and experimental animals suggests that similar doses to the same
tissues, for example lung cells or bone surfaces, from alpha particles emitted
during the decay of different radionuclides produce the same types of non-neoplastic
effects and cancers.
Non-Human Toxicity Excerpts:
/LABORATORY ANIMALS: Acute Exposure/ Neptunium-237 administered intravenously as
a citrate complex was acutely lethal to female rats at dose levels above 6 mg/kg
while males tolerated as much as 24 mg/kg. Hepatic and renal damage was
sustained in all rats at dosages equal to or greater than 6 mg/kg. Hepatic
damage consisted of morphological changes-cloudy swelling, fatty degeneration
and lobular necrosis-and biochemical changes-fat accumulation, elevated Ca2+ and
reduced K+ concentrations. Renal tubular damage was similar to that observed in
uranium poisoning. Both hepatic and renal damage appeared earlier and were more
severe in females leading to their higher sensitivity and greater mortality.
While the acute chemical toxicity of neptunium-237 has been demonstrated,
preliminary calculations indicate that the radiological hazard is more important
for extended exposure, and no change is warranted in the current values fox
maximum permissible body burden or critical organ burden. /Neptunium-237citrate/
/LABORATORY ANIMALS: Acute Exposure/ In order to evaluate the toxicity of
neptunium-237 in a large animal, a neptunium citrate complexed solution was
administered intravenously in doses up to 12 mg (8.3 [micro]c) per kg of body
weight to 1-year-old sheep. Deaths were observed in all the animals administered
12 mg of neptunium-237/kg, and in four out of five animals that received 6
mg/kg. Liver function was impaired, as determined by iodine-131 rose bengal
blood clearance, in animals which received doses as low as 1.5 mg per kg of body
weight. Gross hemorrhages were evident in the livers of the group administered 6
and 12 mg/kg. Histopathological changes observed included neuronal damage in the
brain, together with parenchymal damage in the liver and kidneys. The
microscopic lesions observed generally resembled those resulting from heavy
metal toxicity. /Neptunium-237citrate/
/LABORATORY ANIMALS: Subchronic or Prechronic Exposure/ ... intratracheal
administration of neptunium-237 to rats was performed during 6 weeks. The total
dose administered was 45.8 kBq. Two methods, electron microscopy and electron
probe X-ray microanalysis, were used to determine the intracellular sites of
localization of neptunium-237. Clusters of dense granules were observed in
nuclei of pneumocytes and proximal tubular cells of the kidneys. These clusters
have been shown to contain neptunium associated with phosphorus, sulfur and
calcium. Alterations of nuclei and ultrastructural cytoplasmic lesions were
observed. The absorbed doses in lungs and kidneys were very low. These results
suggest that the chemical toxicity of neptunium-237 is more important than its
radiological toxicity. /Neptunium-237/
/LABORATORY ANIMALS: Chronic Exposure or Carcinogenicity/ A group of 106 male
Sprague-Dawley rats, eight weeks of age, received a single, nose-only exposure
to an aerosol of 237-NpO2 (activity median aerodynamic diameter, 2.6 um;
geometric standard deviation, 2.17). The initial lung burdens of neptumium-237
in individual rats ranged from 0.1 to about 7 kBq. The exposed rats and 785
controls (treatment unspecified) were held for lifetime observation. Animals
were necropsied at death, and the tissues were examined histologically. When the
neptunium-237-exposed rats were divided into four groups on the basis of mean
initial lung burdens of 0.2, 0.5, 2 and 4 kBq, the mean length of survival of
rats at the highest dose, 653 days, was significantly shorter than that of the
unexposed controls (828 days). For the analysis of lung tumors, the exposed rats
were divided into six groups on the basis of doses ranging from 0.6+/-0.1 Gy
(SD) to 26+/ -7 Gy. The numbers of rats with malignant lung tumors in these six
groups, ranked from lowest to highest dose, were 2 of 19, 2 of 20, 5 of 18, 11
of 20, 11 of 14 and 14 of 15. The tumors were primarily adenocarcinomas and
squamous-cell carcinomas. The incidence of adenocarcinomas versus dose fitted a
linear-quadratic relationship, with a threshold for the quadratic component at
doses < 2 Gy. No squamous-cell carcinomas were seen at doses < 2 Gy, and
no adenosquamous carcinomas at doses < 8 Gy. /Neptunium-237 oxide/
/LABORATORY ANIMALS: Chronic Exposure or Carcinogenicity/ The intravenous
injection of neptunium nitrate and oxalate at doses ranging from 2.0 to
0.017uCi/kg was characterized by the occurrence of osteosarcomas (incidence
ranging from 58 to 9% at cumulative skeletal radiation doses ranging from 520 to
5 rads, respectively). The major manifestations of injury after intratracheal
administration of the two neptunium compounds at the same doses were the
development of pneumosclerosis and malignant lung tumors (incidence ranging from
37 to 11% at cumulative lung doses of 3220 to 5 rads, respectively); and, to a
lesser extent, of osteosarcomas (incidence ranging from 25 to 5% at skeletal
doses of 408 to 4 rads, respectively). /Neptunium nitrate and oxalate/
/LABORATORY ANIMALS: Chronic Exposure or Carcinogenicity/ Groups of 40 female
albino Sprague-Dawley rats, 10 to 12 weeks old, were given neptunium-237 at a
dose of 5.2 or 26 kBq/kg bw, and 77 control rats received unspecified treatment
without the radionuclide. Lifetime observations were made on 28 rats in each
exposed group and the 77 controls. At death, all rats were necropsied and
examined histologically. The median survival times were: controls, 800 days; 5.2
kBq/kg bw, 754 days; and 26 kBq/kg bw, 644 days. Control rats developed mainly
mammary tumours (56 of 77) and pituitary tumors (40 of 77). In the treated rats,
mammary tumours were removed surgically to increase the opportunity of observing
radiation-induced effects, which occurred significantly in the skeleton as
osteosarcomas: controls, 1 of 77; 5.2 kBq/kg bw, 1of 28; and 28 kBq/kg bw, 10 of
28. These results reflect the preferential distribution and retention of
neptunium-237 on bone surfaces. /Neptunium-237, NOS/
/LABORATORY ANIMALS: Chronic Exposure or Carcinogenicity/ The results of several
studies of experimental carcinogenesis suggest that, after inhalation of
alpha-particle emitters, lung tumor incidence varies depending on the exposure
rate and dose distribution in the tissue. In the case of transuranics, the main
influencing factor would be the specific alpha-particle activity of the inhaled
actinide. To confirm these results, long-term studies were performed using male
Sprague-Dawley rats exposed to 237-NpO(2) by inhalation. The initial lung
burdens of the animals ranged from 0. 1 to about 7 kBq. The rats were followed
during their life span and weighed regularly, and their lung burdens were
determined in vivo and at death to estimate the lung dose. At death, the
incidence of lung tumors and their malignancy and histological types were
analyzed. The analysis revealed a typically linear-quadratic dose response for
incidence of malignant lung neoplasm and a differential dose response for
various types of tumors. .... /Neptunium-237 oxide/
/LABORATORY ANIMALS: Chronic Exposure or Carcinogenicity/ Female Sprague-Dawley
rats, 10-12-week old and weighing about 240 g, were injected intravenously with
neptunium-237 nitrate. In the toxicological study 77 rats served as controls and
28 rats per group received single doses of 5.2 and 26 kBq, respectively, per kg
body weight. In addition, 12 rats of each injection level, sacrificed at defined
points in time, were used for dosimetric studies. During the whole life-span the
body weight and neptunium-237 whole body-content of each animal were recorded.
After death a detailed pathological examination was made of each animal in the
chronic study. One day after injection 48% of the injected activity was in the
skeleton, 9.3% in the liver, 3% in the kidneys and 4.4% in the rest of the
organs. Whereas in all organs the activity decreased very fast, the half-life in
the skeleton was about 1,400 days. The body weights were comparable in the three
groups, but the life span decreased from 800 days (control group) to 644 days
after injection (26 kBq kg-1 body weight group). The main lesions in the female
rats were mammary tumors (73%) and pituitary gland tumors (52%). With increasing
activity the incidence of pituary gland tumors decreased and that of
osteosarcomas increased from 1.3% (control group) to 32% (26 kBq kg-1 body
weight group), whereas the remaining lesions showed no influence on the
activity. /Neptunium-237 nitrate/
/LABORATORY ANIMALS: Chronic Exposure or Carcinogenicity/ To compare the
incidence of each lung tumor type after inhalation exposure of rats to either
NpO(2) or industrial PuO(2) aerosols, which have a similar size ... male
Sprague-Dawley rats were exposed once and followed during their whole life span.
At the end of their life, the whole lungs were fixed, embedded and cut into thin
sections for histological analysis. The presence of tumors was evaluated on
three distinct levels of the lobes for phenotype determination to establish
dose-effect relationships. ... In the range of lung doses studied (0.05 to more
than 50 Gy), the general trend was an increased frequency of all types of tumors
after inhalation exposure to neptunium compared with plutonium. The linearity of
the lower part of the dose-effect relationships for all malignant lung tumors
leads to the conclusion that NpO(2) is 3.3-fold more carcinogenic than PuO(2).
/Neptunium and plutonium oxides/
/LABORATORY ANIMALS: Chronic Exposure or Carcinogenicity/ To compare survival,
lung dosimetry and gross pathology after inhalation exposure of rats to either
NpO2 or industrial PuO2 aerosols with similar granulometric parameters. ... male
Sprague Dawley rats were exposed once and their lung burdens were measured by
X-ray spectrometry at different times post-exposure up to death. The time-course
of doses delivered to the lungs were estimated, taking into account individual
lung clearance parameters and body and lung weights. Gross lung pathologies were
scored at autopsy. ... In the range of initial lung deposits (ILD) studied (0.1
to 4 kBq), lung clearance impairment and reduced lifespan were only observed
after exposure to NpO2. For similar ILD or doses, the highest incidences of lung
lesions assumed to be tumors were observed for NpO2 with a saturation of lung
tumor induction for doses larger than 8 Gy (ILD: 1.5kBq). Up to 22Gy (ILD:
3.5kBq), such saturation was not observed for PuO2. /The authors concluded that/
NpO2 appears much more toxic than PuO2. Before saturation, lung tumor incidence
increased nearly linearly with dose, the slope of the curve for NpO2 being about
twice as steep as that for PuO2. /Neptunium and plutonium oxides/
/ALTERNATIVE IN VITRO TESTS/ The tumor
suppressor gene Tp53 was analyzed by polymerase chain reaction-amplification of
genomic DNA extracted from paraffin-embedded tissue sections of rat lung tumors
to compare mutations that occurred after inhalation exposures to plutonium
dioxide, neptunium dioxide, or radon and radon progenies. Exons 5 to 8 of the
gene were amplified in 16 plutonium-, 23 neptunium- and 15 radon-induced lung
tumors, and their polymerase chain reaction products were examined for mutations
by single strand conformational polymorphism analysis and direct sequencing
method. Two point mutations were detected in the plutonium-induced tumors, i.e.,
a guanine to adenine transition at codon 219 of exon 6 and a cytosine to thymine
transition at codon 266 of exon 8. Although only one point mutation was found at
codon 175 of exon 5 (cytosine to thymine transition) from neptunium-induced
tumors, no mutations were detectable from radon-induced tumors. These results
indicate that the abnormalities of the Tp53 gene might not be so critical for
the pulmonary carcinogenesis after the inhalation of different alpha emitters,
even though the presence and frequencies of the Tp53 gene mutations were
different. /Plutonium dioxide, neptunium dioxide, or radon and radon progenies/
/OTHER TOXICITY INFORMATION/ A mass-dependent difference in intracellular
localization has been observed for neptunium. In rats 24 hours after intravenous
injection of 1.2 mg/kg bw neptunium-237 or 17 pg/kg bw neptunium-239, the
association of neptunium-237 with the liver cell nuclei was double that found
with neptunium-239. /Neptunium-237 and -239/
/OTHER TOXICITY INFORMATION/ Two methods, electron microscopy and wavelength
dispersive electron probe microanalysis, were used to determine the
intracellular sites and chemical form of concentrations of neptunium-237 nitrate
after chronic intoxication by the intraperitoneal route in two organs in the rat
known to concentrate this element (kidney, liver). Abnormal intranuclear
formations in the form of clusters of dense granules containing neptunium,
phosphorus, sulfur, and calcium were found in the nuclei of kidney proximal
tubule cells and hepatocytes. These formations had a maximum diameter of the
order of 2 microns and were located in the central part of the nucleus, away
from the nucleolus and peripheral chromatin. Serious nuclear
and cytoplasmic ultrastructural lesions are often associated in cells containing
neptunium inclusions. The absorbed doses in the kidney and the liver were very
low. A relationship between these abnormal intranuclear structures and the
carcinogenic effect of neptunium remains to be clarified. This effect is related
more probably to the chemical toxicity of neptunium-237. /Neptunium nitrate/
Biological Half-Life:
In rodents and primates, rapid loss of neptunium from the liver was seen with
half-times of a few months or less In human autopsy samples, neptunium-237 was
removed from the liver at least 15 times more rapidly than plutonium-239.
/Neptunium-237 and plutonium-239/
Interactions:
Rats were administered neptunium-237 nitrate either intravenously or
intramuscularly. Similar distributions in organs were observed after intravenous
injections at pH 1.5 and 7.5. Intramuscular injections were followed by a high
urinary excretion-about 30% of the total administered dose-over the 1st month,
while over 60 % migrated from the injection site. The ratio of activity
eliminated via urine/activity deposited in bone was roughly equal to 1. DTPA
therapy was not effective. Neptunium behavior rather followed that of alkaline
earths than that of transplutonium elements. /Neptunium nitrate/
The estimated intestinal absorption after a single administration of
neptunium-239 nitrate to fasted weanling rats (about 2% of the oral dose) was
ten times higher than that of protactinium-233 administered as the chloride.
Rats drinking tomato juice, apple juice or tea instead of water had a similar
retention to the control group. However, when a small amount of tea was
administered immediately before neptunium-239, the absorption and retention
values were six times lower. When animals received only milk or glucose, the
whole body retention of neptunium-239 and proactinium-233 increased about 20 and
200-300 times, respectively, due mainly to a very high retention in the large
intestine. When rats were fed milk plus rat chow, the whole body and gut
retention of protactinium-233 was only two and three times higher, respectively;
in the other organs less proactinium-233 was found than in control animals. This
indicates that the extremely high retention of radionuclides in the gut contents
of young rats fed only milk is temporary and disappears when solid food is
available. /Neptunium-239 nitrate/
Absorption and retention of neptunium were determined in baboons after
intragastric administration of neptunium nitrate solutions at pH 1. The effects
of mass, diet, and fasting on absorption were studied. At higher mass levels
(400 to 800 micrograms Np/kg), absorption was about 1%; at lower mass intakes
(0.0009 to 0.005 micrograms Np/kg), absorption was reduced by 10- to 20-fold.
The addition of an oxidizing agent (Fe3+) increased gastrointestinal absorption
and supported the hypothesis of a reduction of Np(V) when loss masses were
ingested. Diets depleted of or enriched with hydroxy acids did not modify
retention of neptunium but increased urinary excretion with increasing hydroxy
acid content. The diet enriched with milk components reduced absorption by a
factor of 5. Potatoes increased absorption and retention by a factor 5, not
necessarily due to the effect of phytate. Fasting for 12 or 24 h increased
retention and absorption by factors of about 3 and 10, respectively. ...
/Neptunium nitrate/
Absorption of uranium, neptunium, americium, and curium was increased by factors
of 3.4, 7.1, 2.7 and 1.7, respectively, when nitrate solutions of these
actinides were gavaged to adult rats fed an iron-deficient diet. Retention
increased proportionately in liver, kidney and carcass. The concentration of the
actinides excreted also increased substantially (over that of controls) in the
urine of iron-deficient rats gavaged with 233-U and 237-Np, but not in those
with 241-Am or 244-Cm. Weanling rats on an iron-deficient diet, gavaged with
ferric nitrate immediately before administration of 238-Pu nitrate, retained
between 4% and 12% of the 238Pu retained by litter mates that were not treated
intragastrically with iron. /Uranium. neptunium, americium, and curium nitrates
and iron/
The gastrointestinal absorption and systemic distribution of uranium and
neptunium were determined after external gamma irradiation. ... Rats were
exposed to a single whole-body dose of gamma radiation (6Gy; 0.75Gy/min). Three
days after irradiation they were orally and/or intravenously contaminated with
100 microg/kg uranium or 3kBq/kg neptunium. The gastrointestinal absorption and
organ distribution of both radionuclides were measured 6 days after irradiation.
... External irradiation increased the intestinal transit time of uranium and
neptunium but had no effect on their gastrointestinal absorption. The average
fractional absorption was determined to be 0.93 and 0.98% (uranium) and 4.7 and
4.8% (neptunium) for the irradiated and non-irradiated rats respectively. The
excretion of uranium and neptunium was not affected by the irradiation.
/Neptunium and uranium, NOS/
Neptunium-237(V) nitrate was administered by gavage to groups of fed or fasted
adult and 5-day-old rats. Some groups also received the oxidants quinhydrone or
ferric iron, and others received the reducing agent ferrous iron. Adult mice
received ferric or ferrous iron and neptunium-235. When the adult rats were
killed at 7 days after gavage, measurements showed that, compared with rats that
were fed, a 24-hr fast caused a five-fold increase in neptunium-237 absorption
and retention. Both quinhydrone and ferric iron caused an even greater increase
in absorption in both fed and fasted rats. Ferrous iron, on the other hand,
decreased absorption in fasted rats to values lower than those obtained in fed
rats. Similar results were obtained in mice treated with neptunium-235 and
either ferric or ferrous iron. The highest absorption obtained after gavage of
ferric iron to fasted rats and mice was about two orders of magnitude higher
than the value obtained in animals that were fed before gavage. The effects of
ferric and ferrous iron on neptunium absorption by neonatal rats were similar to
their effects on adult animals but of lesser magnitude. These results are
consistent with the hypothesis that Np(V), when given in small mass quantities
to fed animals, is reduced in the gastrointestinal tract to Np(IV), which is
less well absorbed than Np(V). /Neptunium-237 nitrate/
The transfer of various Np(IV) and Np(V) chemical forms across the small
intestine of rats was measured in instilled and perfused jejunum. Instillation
of Np(V) nitrate together with citrate or DTPA resulted in the same absorption
of neptunium as after instillation of Np(V) nitrate alone (3 per cent per hour).
Perfusion of Np(V) nitrate with bicarbonate or DTPA resulted in a similar
transfer (2 per cent) but added citrate or ascorbate resulted in reduced
transfer (0.8 per cent). Addition of phytate reduced neptunium transfer in both
instilled and perfused jejunum (0.4 per cent). Np(IV) transfer was usually the
same as, or less than that of, the corresponding Np(V) forms. Np(IV) transfer
was similar in perfused and instilled jejunum, increasing from 0.2 per cent in
the presence of citrate and phytate, to 1 per cent with EDTA and DTPA. Except
for phytate, all the forms of Np(V) tested behaved like Np(V) nitrate after
transfer from the intestine or after intravenous injection. By contrast, the
behavior of Np(IV) varied for all the forms tested and, for a given form, varied
as a function of the experimental procedure used, i.e. jejunal instillation,
perfusion, or intravenous injection. These findings suggest that the intestinal
transfer of neptunium might occur via the intercellular pathway, and that it is
controlled by both the molecular weight of the neptunium compound and its
stability constant. /Various Np(IV) and Np(V) forms/
It was demonstrated in rats that it is possible to reduce the retention of
neptunium-239 in all body tissues by an early combined treatment with small
doses of desferrioxamine B (DFOA) and diethylenetriaminepentaacetic acid (DTPA).
The content of neptunium-239 can be decreased in soft tissues even if treatment
is delayed. Promptly administered /the carboxylated catechoylamide
3,4,3-LICAM(C)/ proved more effective than the above chelate combination in
reducing neptunium-239 retention in the bones but increased that in the muscles
and especially in the kidneys. This side effect of LICAM(C) could be partly
prevented by simultaneous treatment with DTPA. /Neptunium-239, NOS/
Environmental Fate & Exposure:
Environmental Fate/Exposure Summary:
Neptunium was the first synthetic transuranium element of the actinide series
discovered. Neptunium-239 (half-life = 2.4 days) was first produced in 1940 at
Berkeley, CA by the bombardment of uranium-238 with cyclotron-produced neutrons.
Seventeen isotopes of neptunium are known and all are radioactive. Neptunium-237
is obtained in gram quantities as the by-product from nuclear
reactors in the production of plutonium. The longest lived isotope is Np-237; it
is an alpha-emitter with a half-life of 2.14 million years. Neptunium is a
by-product of plutonium production activities. Neptunium is present in spent nuclear
fuel, high-level radioactive wastes
resulting from the processing of spent nuclear
fuel, and radioactive wastes
associated with operations of reactors and fuel reprocessing
plants. A small amount of neptunium
would have been generated by atmospheric nuclear
weapon testing, which ceased worldwide by 1980. The amount of neptunium in soil
from past nuclear testing is on the
order of 0.0001 pCi/g. Releases of neptunium from weapons production facilities
have cause localized contamination. There are no major commercial uses of
neptunium. Trace quantities of neptunium are found in nature associated with
uranium ores. Neptunium compounds are ionic and would not be volatile and would
exist solely in the particulate phase in the ambient atmosphere.
Particulate-phase neptunium compounds will be removed from the atmosphere by wet
or dry deposition. In soil, neptunium is generally more mobile than other
transuranic elements such as plutonium, americium, and curium, moving with
percolating water to lower soil layers. Neptunium compounds bind to soil
particles, and bind more tightly with clay soils as compared with sandy soils.
Neptunium is readily taken up by plants,
with plant concentrations similar to
soil concentrations. Neptunium compounds are ionic and would not volatilize from
moist or dry soil surfaces. Neptunium has 4 valence states in water: Np3+; Np4+;
NpO+; and (NpO)2+. Neptunium forms tri- and tetrahalide compounds such as NpF3,
NpF4, NpCl4, NpBr3, NpI3, and oxides of various compositions such as Np3O8 and
NpO2. Since neptunium has only been produced in limited quantities and it has
few uses outside of research activities, exposure to neptunium compounds would
be limited to individuals involved in scientific research using neptunium or at
plutonium production or nuclear waste
facilities. (SRC)
Probable Routes of Human Exposure:
Since neptunium has only been produced in limited quantities(1) and it has few
uses outside of research activities(2), exposure to neptunium compounds would be
limited to individuals involved in scientific research using neptunium or at
plutonium production or nuclear waste
facilities(SRC).
Natural Pollution Sources:
Trace quantities of neptunium are found in nature associated with uranium
ores(1,2). The ratio of neptunium-237 to uranium-238 in uranium minerals is
1.8X10-12 to 1 (atom-to-atom ratio)(3).
Artificial Pollution Sources:
Neptunium was the first synthetic transuranium element of the actinide series
discovered(1,2). Neptunium-239 (half-life = 2.4 days) was first produced in 1940
at Berkeley, CA by the bombardment of uranium-238 with cyclotron-produced
neutrons(1,2). Seventeen isotopes of neptunium are known and all are
radioactive(1). Neptunium-237 is obtained in gram quantities as the by-product
from nuclear reactors in the
production of plutonium(2). The longest lived isotope is neptunium-237; it is an
alpha-emitter with a half-life of 2.14 million years(3). Neptunium is a
by-product of plutonium production activities(1). Neptunium is present in spent nuclear
fuel, high-level radioactive wastes
resulting from the processing of spent nuclear
fuel, and radioactive wastes
associated with operations of reactors and fuel reprocessing
plants(1). A small amount of neptunium
would have been generated by atmospheric nuclear
weapon testing, which ceased worldwide by 1980(1). The amount of neptunium in
soil from past nuclear testing is on
the order of 0.0001 pCi/g(1). Releases of neptunium from weapons production
facilities have caused localized contamination(1). There are no major commercial
uses of neptunium(1). Neptunium forms tri- and tetrahalide compounds such as
NpF3, NpF4, NpCl4, NpBr3, NpI3, and oxides of various compositions such as Np3O8
and NpO2(2).
Environmental Fate:
TERRESTRIAL FATE: Neptunium typically occurs as the oxide in the environment(1).
In soil, neptunium is generally more mobile than other transuranic elements such
as plutonium, americium, and curium, moving with percolating water to lower soil
layers(1). Neptunium compounds bind to soil particles, and bind more tightly
with clay soils as compared with sandy soils(1). Neptunium is readily taken up
by plants, with plant
concentrations similar to soil concentrations(1). Neptunium compounds are ionic
and would not volatilize from moist or dry soil surfaces(SRC).
AQUATIC FATE: Neptunium ions would be expected to adsorb to suspended particles
in water(SRC), since actinide ions with III, IV, and VI oxidation states can be
adsorbed to cation-exchange resins(1). Neptunium is a member of the actinide
series and would be expected to behave similarly(SRC). Neptunium can exist as
the following ions in water: Np3+ (pale purple); Np4+ (yellow green); NpO+
(green blue); and (NpO)2+ (pale pink)(2). The pentavalent state is the most
stable ion in aqueous solution(3). Neptunium 3+ ion is stable in water but is
readily oxidized by air to the 4+ state(1). Neptunium 4+ ion is stable in water,
but is slowly oxidized by air to (NpO2)+(1). (NpO2)+ ion is stable in aqueous
solution, and disproportionates only at high activities(1). (NpO2)2+ is stable
in aqueous solution, but can be easily reduced(1). (NpO5)3- only exists in
alkaline solution(1). Since neptunium compounds are ionic, they will not
volatilize from water surfaces(SRC). Bioconcentration is not expected to be an
important fate due to the ionic nature of neptunium compounds(SRC).
ATMOSPHERIC FATE: Neptunium compounds are ionic and would not be volatile and
would exist solely in the particulate phase in the ambient atmosphere.
Particulate-phase neptunium compounds will be removed from the atmosphere by wet
or dry deposition. (SRC)
Environmental Abiotic Degradation:
In aqueous solution, neptunium compounds may undergo oxidation-reduction and
ligand exchange reactions(SRC). Neptunium can exist in the 3, 4, 5, 6 and 7
valence states(1). The 5+ state is the most stable ion in aqueous solution(1).
Tetravalent neptunium is readily oxidized to the 6+ state by strong oxidizing
agents(1).
Environmental Bioconcentration:
Bioconcentration is not expected to be an important fate due to the ionic nature
of neptunium compounds. (SRC)
Neptunium is readily taken up by plants,
with plant concentrations similar to
soil concentrations(1).
Soil Adsorption/Mobility:
In soil, neptunium is generally more mobile than other transuranic elements such
as plutonium, americium, and curium, moving with percolating water to lower soil
layers(1). Neptunium compounds bind to soil particles, and bind more tightly
with clay soils as compared with sandy soils(1).
Volatilization from Water/Soil:
Neptunium compounds are ionic and would not volatilize from moist or dry soil
surfaces or from water surfaces. (SRC)
Environmental Water Concentrations:
Neptunium-237 concentrations in porewater collected over a year from an
inter-tidal salt marsh in the Esk Estuary, West Cumbria, UK near the British Nuclear
Fuel Ltd Sellafield nuclear fuel reprocessing
plant ranged from approximately 0.05
mBq/L in September to 0.56 mBq/L in March(1).
Sediment/Soil Concentrations:
SOIL: A small amount of neptunium would have been generated by atmospheric nuclear
weapon testing, which ceased worldwide by 1980(1). The amount of neptunium in
soil from past nuclear testing is on
the order of 0.0001 pCi/g(1).
SEDIMENT: The British Nuclear Fuels
Ltd nuclear fuel reprocessing
plants at Sellafield in Cumbria, UK
discharge low level radioactive waste
into the Irish Sea(1). Neptunium-237 concentrations in sediment cores samples
collected in October 1994 from 9 sites around the intertidal area of the Irish
Sea, UK ranged from 13.1 to 412 mBq/kg(1)
Environmental Standards & Regulations:
Chemical/Physical Properties:
Color/Form:
Silvery appearance /Elemental/
Boiling Point:
4174 deg C (extrapolated) /Elemental/
Melting Point:
644 deg C /Elemental/
Density/Specific Gravity:
Specific gravity: 20.25 at 20 deg C /Elemental/
Other Chemical/Physical Properties:
There are 23 isotopes and isomers of neptunium(1). Trace quantities of the
element are actually found in nature due to transmutation reactions in uranium
ores produced by the neutrons which are present(1). All neptunium isotopes are
radioactive(2).
Atomic number 93; valence: 3, 4, 5, 6; twenty-three isotopes and isomers are
recognized; neptunium metal is chemically reactive
Neptunium-237: Atomic weight = 237.048166; half-life = 2.14x10+6 years; alpha
decay; 4.957 MeV; spontaneous fission, 2.1x10-10 MeV
Neptunium-239: Atomic weight = 239.052931; half-life = 2.117 days; beta(-)
decay; 1.292 MeV
First synthetic transuranium element; no stable nuclides; known isotopes (mass
numbers): 227-242; silvery metal; develops a thin oxide layer upon exposure to
air for short periods; reacts with air at high temperatures to form NpO2;
exhibits 3 allotropic modifications: othrorhombic alpha-form; density = 20.45;
transforms to beta-form at 280 deg C; tetragonal beta-form: density = 19.36
transforms to gamma-form at 577 deg C; cubic gamma-form: transforms to liquid at
melting point, 637 deg C
DECAY PATHWAY: Neptunium-237, half-life 2,144,000 years, decays via alpha
emission, 4.959 MeV, to protactinium-233, half-life 26.967 days.
Protactinium-233 decays via beta emission, 0.571 MeV, to uranium-233, half-life
159,200 years.
DECAY PATHWAY: Neptunium-239, half-life 2.3565 days, decays via beta(-)
emission, 0.722 MeV, to plutonium-239, half-life 24,110 years. Plutonium-239
decays via alpha emission, 5.245 MeV, to uranium-235, half-life 703,800,000
years.
Metallic neptunium forms a protective oxide layer in air at room temperature,
but it rapidly oxidizes at higher temperatures. It dissolves readily in HCl and
H2SO4.
Five binary oxides or oxide hydrates of neptunium: NpO2, Np2O5, Np3O8, NpO3.2H2O
and NpO3.H2O. Anhydrous Np(VI) oxide has not been prepared. Neptunium dioxide,
NpO2, is the most stable of the neptunium oxides. It crystallizes with the
fluorite structure of all the actinide dioxides, with a crystalline density of
11.14 g/cu cm. ... High-fired NpO2 can be dissolved in hot concentrated nitric
acid containing small amounts of fluoride. The mixed oxide Np3O8 is structurally
analogous to U3O8. Above 500 deg C it decomposes to NpO2. /Neptunium oxides/
In aqueous solution neptunium exists in the five oxidation states Np(III), Np(IV),
Np(V), Np(VI), and Np(VII), although the heptavalent Np(VII) is stable only in
alkaline solutions. In the absence of complexing agents the first four oxidation
states exist as Np+3, Np+4, NpO2+, and NpO2+2, usually in the hydrated form. ...
Pentavalent neptunium is the most stable state in solution. ... Hexavalent
neptunium is much less stable in solution than is hexavalent plutonium; in fact,
hexavalent neptunium is a strong oxidizing agent and is easily reduced in the
presence of oxidizable substances, such as those present in ion-exchange and
solvent extraction separations. ..Trivalent neptunium is stable only in the
absence of oxygen, being oxidized to Np(IV) in aqueous solutions exposed to air.
Tetravalent neptunium forms strong complexes with anions, but Np(V) forms only
weak complexes. ...
Silvery-white metal; exhibits three crystalline modifications: an orthorhombic
alpha form, stable at ordinary temperatures and density 20.45 g/cm3; the
alpha-form transforms to a tetragonal beta allotrope of density 19.36 g/cm3 when
heated at 280 deg C; the beta form converts to a body-centered cubic crystalline
gamma modification at 577 deg C, having a density 18.0 g/cm3. The metal melts at
644 deg C; boils at 3,902 deg C (estimated); dissolves in hydrochloric acid.
/Neptunium metal forms/
Neptunium metal reacts with hydrogen under milder conditions at 50 deg C and one
atmospheric pressure, forming hydrides of varying stoichiometric compositions.
The metal combines with carbon at 1,200 deg C, forming two carbides, NpC and
Np2C3. Heating the trifluoride, NpF3 with silicon at 1,500 deg C forms neptunium
silicide, NpSi2.Many other neptunium compounds have been prepared and their
crystal structures determined. These include the black orthorhombic sulfide,
Np2S3, and the tetragonal oxysulfide, NpOS, and the pink hexagonal oxofluoride,
NpO2F2. Neptunium also is known to form many intermetallic compounds with
aluminum, beryllium and other metals. In solution, neptunium oxidizes to Np3+
and Np4+ ions, the salts of which are pink and greenish-yellow, respectively.
Unlike its rare earth analog promethium, neptunium also forms oxoions, such as,
NpO+ (blue green) and NpO2+ (light pink).
Neptunium solubility is strongly dependent upon oxidation state. The +3 and +4
states form very insoluble fluorides, while the (V) and (VI) states are soluble.
This property is an effective means of separation of neptunium from uranium.
Neptunium (+4) may be carried on zirconium phosphate precipitate, indicating its
insolubility as a phosphate only in that oxidation state. Neptunium forms two
oxides, NpO2 and Np3O8, both of which are soluble in concentrated hydrochloric,
perchloric and nitric acids. The most soluble of the neptunium compounds are
Np(SO4)2, Np(C2O4)2, Np(NO3)5, Np(IO3)4, and (NH4)2Np2O7. Neptunium (+3)
compounds are easily oxidized to Np+4 when exposed to air.
Chemical Safety & Handling:
Protective Equipment & Clothing:
Protective clothing, commonly of Tyvex material, is used to keep contamination
off personal clothing and skin. It does not stop the external radiation exposure
(except alpha rays), but it helps prevent the spread of contamination both onto
and into the body. /Plutonium facilities/
During operations in which there is a potential to breach a containment system
(such as glove changes or seal-outs) and create airborne radioactivity,
respiratory protection is the primary method of preventing internal dose from
inhalation. To minimize the possibility of inhalation, individuals must ensure
the physical integrity of the respirator, obtain a good seal, and ensure the
protection factor of the respirator is adequate. There are also methods to
prevent injection wounds (such as placing leather gloves over glovebox gloves or
ensuring there are no sharp objects inside containments). If personnel have any
suspicion of an injection wound, they should immediately seek the assistance of
the site radiological control organization. /Plutonium facilities/
In most /emergency/ situations, respiratory protection that is designed to
protect responders against chemical or biological agents is likely to offer some
degree of respiratory protection in a radiological attack. Concerns about the
presence of chemical or biological contaminants will influence the selection of
respiratory protection. If used properly, simple face masks provide reasonably
good protection against inhaling particulates, and allow sufficient air transfer
for working at high breathing rates. If available, high-efficiency particulate
air filter masks provide even better protection.
Preventive Measures:
In any facility that handles radioactive materials, the major controls
protecting workers, the public, and the environment are structures and installed
equipment, which shield, contain, and confine the radioactive materials.
However, to allow useful work to be performed in the facility and to assure that
its protective features remain effective, a number of administrative controls
are ordinarily required. These administrative controls are usually contained in
a series of procedures related to the operations and maintenance activities to
be carried out in the facility. All personnel who work in controlled areas
should be familiar with the administrative controls that apply to their work.
When changes or additions to administrative controls are made, these changes or
additions should be effectively communicated to all persons who may be affected.
/Plutonium facilities/
Radiation Protection Procedures: A .... facility should have a written policy on
radiation protection, including a policy on keeping exposures ALARA. All
radiation protection procedures and controls should have formal, recognizable
technical bases for limits, methods, and personnel protection standards.
Procedures should be adequately documented, updated periodically, and maintained
in a centralized historical file. A control system should be established to
account for all copies and ensure that all new procedures are included in the
historical files. A designated period of time for maintaining historical files
should be established. ... In addition, radiation protection procedures should
have a documented approval system and established intervals for review and/or
revision. A tracking system should be developed to ensure that the required
reviews and revisions occur. /Plutonium facilities/
A thorough radiation protection training program should be established ... .
Separate training programs should be established for general employees,
radiation workers, and radiation control technicians. The training of all staff
members should be carefully documented. /Plutonium facilities/
Source reduction: The source of the radiation can be reduced by decontamination,
better storage methods, or elimination of the source altogether. Extremity dose
can be reduced by periodically sweeping/wiping the... dust from the inside of
the gloveboxes and gloves. /Plutonium facilities/
Gloveboxes are almost always used when handling /transuranic alpha emitters/ ...
in a dispersible form. However, properly vented hoods are acceptable for
handling the very small quantities used in a research laboratory. Proper hood
design is critical ... and only very small quantities should be used. Gloveboxes,
tanks, and piping are examples of "primary containments," because
there are no system openings. Gloveboxes have ports with long plastic sleeves
attached that allow material to be "sealed in" or "sealed
out" from the glovebox without breaching the containment. Types of
equipment such as fume hoods are "primary confinements," since they
are the barrier closest to the source. Primary barriers require good ventilation
to maintain contamination control. Do not insert your hands into a primary
barrier unless you have been trained and authorized to do so. /Plutonium
facilities/
Administrative controls: There are many administrative controls to reduce doses.
The following are just a few that should apply to all sites: Posting. Training.
Housekeeping. Maintaining Access Control. Using Radiation Work Permits. Stopping
work. /Plutonium facilities/
Contamination surveys should be performed to determine surface contamination
area (SCA) boundaries, the appropriate posting of sources or areas, and the
location and extent of localized contamination. Contamination surveys should be
performed and documented prior to the start of radiological work, during general
work activities at times when changes in contamination level may occur, and
following work to assure that final radiological conditions are acceptable and
documented. A sufficient number of points should be surveyed to adequately
assess the radiological status of the area being surveyed. /Plutonium
facilities/
Personnel contamination monitors: Personnel survey instruments are usually
placed at the exits from radiologically controlled areas. Personnel frisking
shall be performed after removal of protective clothing and prior to washing and
showering. The use of a personnel contamination monitor (such as a portal
monitor or hand and foot counter), if available, is encouraged... . Personal
items such as notebooks, papers, flashlights, shall be subjected to the same
frisking. /Plutonium facilities/
Facilities are required to sample the air in areas where an individual is likely
to receive an exposure of 40 or more DAC-hours in a year. Real-time air
monitoring /must/ be performed to detect and provide warning of airborne
radioactivity concentrations that warrant immediate action to terminate
inhalation of airborne radioactive material. Fixed air samplers are used in
these areas (they may also be in areas with CAMs). They are sensitive to low
levels of airborne radioactivity (they are capable of determining a fraction of
a DAC), but do not have alarm capabilities to alert workers to airborne
radioactivity. /Plutonium facilities/
Responsibilities should be assigned for action in response to an accidental
internal ... contamination. The affected worker has the responsibility to inform
the health physicist, Radiation Control Technician, or his immediate supervisor
as soon as an intake is suspected. ... The health physicist or RCT should make
an initial survey of the extent of the contamination and immediately contact his
supervisor and, when action levels are exceeded, contact a member of the medical
staff. /S/He should continue to provide monitoring and radiation safety support
to the medical staff and supervisors during the management of the contamination
incident. Care should be taken to limit the spread of radioactive contamination.
The health physicist should immediately begin to gather data on the time and
extent of the incident. Contamination survey results should be recorded.
Radionuclide identity, chemical form, and solubility classification should be
determined. Nasal smears should be obtained immediately if an intake by
inhalation is suspected. When action levels are exceeded, all urine and feces
should be collected and labeled for analysis. Decontamination should proceed
with the assistance of the medical staff. Contaminated clothing and other
objects should be saved for later analysis. /Plutonium facilities/
Shipment Methods and Regulations:
Regulating the safety of ... shipments /of radioactive materials/ is the joint
responsibility of the NRC and the Department of Transportation (DOT). The NRC
establishes requirements for the design and manufacture of packages for
radioactive materials. The DOT regulates the shipments while they are in transit
and sets standards for labeling these packages and for smaller quantity
packages. /Radioactive materials/
Cleanup Methods:
In most cases, contamination should be controlled, and removed as soon as
possible. The contaminated area or equipment should be marked and posted
immediately. Nonessential persons should be moved out of the area until
decontamination has been completed. Usually simple cleaning techniques and
procedures are adequate for most decontamination tasks. Spills and contaminated
areas should be cleaned from the outer region inward to reduce the possibility
of further spread of the contamination. After cleaning, the area or equipment
should be surveyed to ensure that all the contamination has been removed.
National Council on Radiation Protection and Measurements.
Decontamination is most successful when the material can be recycled for use in
a nuclear facility since the need to
prove releasability (cleanliness) is eliminated. Nevertheless, cleaning material
for unrestricted release is also possible in some cases. It may also be possible
to decontaminate an item enough to change its classification from TRU/transuranic/
waste to LLW /low-level waste/,
thereby allowing immediate disposal of the item, while a relatively small
quantity of decontamination waste is
stored as TRU waste. Electropolishing
to remove the thinnest metal surface has been very effective and produces a
relatively small waste volume,
especially when one of the wetted sponge units is used rather than an emersion
tank. Surface scabbling has been used in decontamination of concrete, and
various abrasive blasting methods have also been effective. Strippable and
self-stripping coatings may be used to decontaminate surfaces, even though the
primary application of strippable coatings has been in preventing contamination
of surfaces. /Plutonium facilities/
Disposal Methods:
/SRP/ Wastes in the Waste
Isolation Pilot Plant (WIPP) are from
the nuclear weapons industry
(plutonium) - research and development. For a waste
to be accepted at WIPP it must be a transuranic "TRU" waste
and: (1) </= 100 nanoCi/gram, (2) an alpha emitting transuranium isotope with
atomic number greater than uranium, and (3) have a half life greater than 20
years. The wastes must be handled
remotely if they produce >/= 200 millirems/hr; if less, they can be contact
handled.
Program design decisions can affect TRU waste-generation.
For example, the quantity of protective clothing may be a significant factor. If
an incinerator is available, combustible protective clothing may be selected to
have a low ash content and generate a minimum of harmful effluents such as
oxides of nitrogen or halogenated compounds. In other facilities,
water-washable, reusable protective clothing may minimize waste
disposal. /Plutonium facilities/
Another opportunity for waste
minimization occurs when materials are used as a contingency protection against
contamination. For example, strippable coatings may be applied to an area that
is not expected to become contaminated or may receive only minor contamination
so that it can be easily cleaned. Another example involves the disposition of
disposable surgeons' gloves, which are routinely worn inside glove-box gloves.
Unless there are serious contamination control problems in the facility, these
can be surveyed and disposed of as sanitary waste
rather than LLW or TRU waste.
/Plutonium facilities/
Likewise, all tools and equipment to be placed in a contaminated environment
should be tested for reliability and preferably used on a clean mock-up to
ensure their serviceability before they become contaminated. There is often a
temptation to put the equipment into the plutonium service when it first arrives
rather than test it completely first. This can result in unnecessary waste
volume. /Plutonium facilities/
Radiation Limits & Potential:
DECAY PATHWAY: Neptunium-237, half-life 2,144,000 years, decays via alpha
emission, 4.959 MeV, to protactinium-233, half-life 26.967 days.
Protactinium-233 decays via beta emission, 0.571 MeV, to uranium-233, half-life
159,200 years.
DECAY PATHWAY: Neptunium-239, half-life 2.3565 days, decays via beta(-)
emission, 0.722 MeV, to plutonium-239, half-life 24,110 years. Plutonium-239
decays via alpha emission, 5.245 MeV, to uranium-235, half-life 703,800,000
years.
Half-life = 2.14X10+6 years /Neptunium-237/
Half-life = 2.355 days /Neptunium-239/
Specific Activity (Ci/g): neptunium-235 1,400; neptunium-236 0.014;
neptunium-237 0.00071.
ALI values have been established for individual radionuclides and are presented
in Table 1 in Appendix B to PART 20.1001-20.2401. The ALI values for inhalation,
presented in Column 2 in Table 1, correspond to a committed effective dose
equivalent of 5 rems (0.05 Sv) or a committed dose equivalent of 50 rems (0.5 Sv)
to any individual organ or tissue, whichever is more limiting. If the ALI value
presented in Table 1 is limited by the 50-rem committed dose equivalent, the
controlling organ is listed directly below the ALI value, and the stochastic ALI
value based on the 5-rem committed effective dose equivalent is listed ...
directly below the organ name. If a stochastic ALI is listed ..., that value
should be used to calculate the committed effective dose equivalent.
OCCUPATIONAL VALUES FOR NEPTUNIUM RADIONUCLIDES (All compounds Class W)
| RADIONUCLIDE | ORAL Ingestion ALI (uCi) | INHALATION ALI (uCi) | INHALATION DAC (uCi/mL) |
|---|---|---|---|
| Neptunium-232 | 1E+5 | 2E+3 (Bone Surf) 5E+2 | 7E-7 |
| Neptunium-233 | 8E+5 | 3E+6 | 1E-3 |
| Neptunium-234 | 2E+3 | 3E+3 | 1E-6 |
| Neptunium-235 | 2E+4 (lower large intestine (LLI) wall) 2E+4 | 8E+2 (Bone Surf) 1E+3 | 3E-7 |
| Neptunium-236 (1.15E+5 Y) | 3E+0 (Bone Surf) 6E+0 | 2E-2 (Bone Surf) 5E-5 | 9E-12 |
| Neptunium-236m (22.5 hr) | 3E+3 (Bone Surf) 4E+3 | 3E+1 (Bone Surf) 7E+1 | 1E-8 |
| Neptunium-237 | 5E-1 (Bone Surf) 1E+0 | 4E-3 (Bone Surf) (1E-2) | 2E-12 |
| Neptunium-238 | 1E+3 | 6E+1 (Bone Surf) 2E+2 | 3E-8 |
| Neptunium-239 | 2E+3 (LLI wall) 2E+3 | 2E+3 | 9E-7 |
| Neptunium-240 | 2E+4 | 8E+4 | 3E-5 |
| RADIONUCLIDE | EFFLUENT CONCENTRATIONS: Air (uCi/mL) | EFFLUENT CONCENTRATIONS: Water (uCi/mL) |
|---|---|---|
| Neptunium-232 | 6E-9 | 2E-3 |
| Neptunium-233 | 4E-6 | 1E-2 |
| Neptunium-234 | 4E-9 | 3E-5 |
| Neptunium-235 | 2E-9 | 3E-4 |
| Neptunium-236 (1.15E+5 y) | 8E-14 | 9E-8 |
| Neptunium-236m (22.5 hr) | 1E-10 | 5E-5 |
| Neptunium-237 | 1E-14 | 2E-8 |
| Neptunium-238 | 2E-10 | 2E-5 |
| Neptunium-239 | 3E-9 | 2E-5 |
| Neptunium-240 | 1E-7 | 3E-4 |
| RADIONUCLIDE | QUANTITY (uCi) |
|---|---|
| Neptunium-232 | 1 |
| Neptunium-233 | 1,000 |
| Neptunium-234 | 100 |
| Neptunium-235 | 100 |
| Neptunium-236 (1.15x10+5 y) | 0.001 |
| Neptunium-236 (22.5 hr) | 1 |
| Neptunium-237 | 0.001 |
| Neptunium-238 | 10 |
| Neptunium-239 | 100 |
| Neptunium-240 | 1,000 |
Threshold Limit Values:
The Physical Agents TLV Committee accepts the occupational exposure guidance of
the International Commission on Radiological Protection (ICRP). ... ICRP
Guidelines for Exposure to Ionizing Radiation: Effective Dose (a) in any single
year, 50 mSv, (b) averaged over 5 years, 20 mSv per year. Annual Equivalent Dose
to: (a) lens of the eye, 150 mSv, (b) skin, 500 mSv, (c) hands and feet, 500 mSv.
Embryo-Fetus exposures once the pregnancy is known - monthly equivalent dose 0.5
mSv - dose to the surface of women's abdomen (lower trunk) 2 mSv for the
remainder of the pregnancy - intake of radionuclide one twentieth of Annual
Limit on Intake (ALI).
The Physical Agents TLV Committee accepts the occupational exposure guidance of
the International Commission on Radiological Protection (ICRP). Ionizing
radiation includes particulate radiation (e.g., alpha particles and beta
particles emitted from radioactive materials, and neutrons from nuclear
reactors and accelerators) and electromagnetic radiation (e.g., gamma rays
emitted from radioactive materials and x-rays from electron accelerators and
x-ray machines) with energy greater than 12.4 electron-volts (eV) ... The
guiding principle of radiation protection is to avoid all unnecessary exposures.
ICRP has established principles of radiological protection. There are (1) the
justification of a work practice: No work practice involving exposure to
ionizing radiation should be adopted unless it produces sufficient benefit to
the exposed individuals or the society to offset the detriment it causes. (2)
The optimization of a workpractice: All radiation exposures must be kept as low
as reasonably achievable (ALARA), economic and social factors being taken into
account. (3) The individual dose limits: The radiation dose from all relevant
sources should not exceed the /ICRP/ prescribed dose limits.
Manufacturing/Use Information:
Major Uses:
To produce plutonium-238 for use as a heat source for thermoelectric devices,
neptunium has been recovered from irradiated uranium to form target elements for
further irradiation in reactors /Neptunium-237/
There are no major commercial uses of neptunium, although neptunium-237 is used
as a component in neutron detection instruments. Neptunium-237 can also be used
to make plutonium-238 (by absorption of a neutron). Neptunium is considered
useable in nuclear weapons, although
no country is known to have used it to make a nuclear
explosive device. /Neptunium-237/
Neptunium-238 has displaced neptunium-239 as a tracer for chemical studies.
Neptunium-237 is used in neutron detection instruments.
Methods of Manufacturing:
Neptunium is a byproduct of plutonium production activities and results from the
capture of neutrons by uranium isotopes, usually in a nuclear
reactor. Neptunium isotopes can be formed by a variety of neutron cpature and
radioactive decay routes. ... Although neptunium is essentially not naturally
present in the environment, very minute amounts may be associated with uranium
ores.
The isotope neptunium-236 is formed in reactors by (n, 2n) reactions in
neptunium-237.
The isotope neptunium-237 is formed in considerable quantities in reactors, by
the nuclide chains initiated by (n, gamma) reactions in uranium-235 and by (n,
2n) reactions in uranium-238. Neutron capture by neptunium-237 leads through
neptunium-238 to plutonium-238, which is the principal alpha-emitting
constituent of plutonium in power reactors.
The isotope neptunium-238 is the 2.1 day beta emitter formed by neutron capture
in neptunium-237. With the availability of separated neptunium-237 from fuel reprocessing,
neptunium-238 is easily made by irradiation of the neptunium-237 target.
The isotope neptunium-239 is formed by neutron capture in uranium-238 or by
decay of americium-243. The latter method is the easiest for laboratory
preparation, if separated americium is available. Reactor-produced americium
will not produce pure neptunium-239, however, because of the presence of
americium-241, which decays to neptunium-237.
Metallic neptunium is obtained by first preparing neptunium trifluoride, which
is reduced with barium vapor at 1200 deg C. /Neptunium metal/
Among its oxides, the green dioxide, NpO2 may be obtained by thermal
decomposition of its nitrate, hydroxide, or oxalate at 700 to 800 deg C. Two
other oxides, a dark brown Np2O5 and a brown Np3O8, also are known. All these
oxides may be prepared by several methods, including heating the hydroxide
Np(OH)5 in air above 275 deg C, or by treating neptunium metal with molten
lithium perchlorate in the presence of ozone. /Neptunium oxides/
Neptunium forms a number of halides in various oxidation states. These include
tri-, tetra- and hexafluorides of compositions NpF3, NpF4, and NpF6,
respectively; trichloride, NpCl3 and tetrachloride, NpCl4; tribromide, NpBr3;
and the triiodide NpI3. Neptunium fluorides are formed by heating neptunium
dioxide at elevated temperatures with fluorine in the presence of hydrogen
fluoride. The tetrachloride, NpCl4 is obtained similarly by heating the dioxide
with carbon tetrachloride vapor at temperatures above 500 deg C. Neptunium
tribromide and triiodide are prepared by heating the dioxide in a sealed vessel
at 400 deg C with aluminum bromide and aluminum iodide, respectively. /Neptunium
halides/
General Manufacturing Information:
In normal reprocessing of irradiated
uranium fuel, neptunium appears in the high-level wastes.
Because of its long half-life of 2.14x10+6 years, neptunium-237 persists in
these wastes long after most of the
fission products and other actinides have decayed. It undergoes alpha decay in
the 2n+1 decay chain to form protactinium-233, which subsequently decays to
uranium-233. to thorium-229, and thence to radium-225 and its decay daughters.
Because of its half-life and the radiotoxicity of its daughters, neptunium-237
is the source of important long-term toxicity in high-level wastes.
If the radionuclides in these wastes
ever become dissolved in groundwater, the chemistry of neptunium is such that it
may not be as effectively retarded by sorption in geologic media as are the
other actinides in these wastes.
/Neptunium-237/
Only three have half-lives long enough to warrant concern at the Department of
Energy (DOE) environmental management sites: neptunium-235, neptunium-236, and
neptunium-237. The half-lives of these three isotopes range from 1.1 to 2.1
million years, while those of the other isotopes are less than five days. Of the
three, neptunium-237 is the most prevalent isotope at DOE sites such as Hanford.
... The other two isotopes typically represent less than a few percent of the
total neptunium inventory at a site. /Neptunium isotopes/
Neptunium-239 (half-life = 2.4 days) was first produced in 1940 at Berkeley, CA
by the bombardment of uranium-238 with cyclotron-produced neutrons.
Neptunium-237 is obtained in gram quantities as the by-product from nuclear
reactors in the production of plutonium.
PLUTONIUM, RADIOACTIVE