・ロニウム

関: Po

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a radioactive metallic element that is similar to tellurium and bismuth; occurs in uranium ores but can be produced by bombarding bismuth with neutrons in a nuclear reactor (同)Po, atomic number 84
a European river; flows into the Adriatic Sea (同)Po River

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ポロニウム(放射性元素;化学記号はPo)
poloniumの化学記号

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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2015/07/22 02:48:02」(JST)

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Polonium is a chemical element with symbol Po and atomic number 84, discovered in 1898 by Marie Curie and Pierre Curie. A rare and highly radioactive element with no stable isotopes, polonium is chemically similar to bismuth and tellurium, and it occurs in uranium ores. Applications of polonium are few. They include heaters in space probes, antistatic devices, and sources of neutrons and alpha particles. Because of its position in the periodic table, polonium is sometimes classified as a metalloid.^[3] Other sources say that on the basis of its properties and behavior, it is "unambiguously a metal".^[4]

1 Characteristics
- 1.1 Isotopes
- 1.2 Solid state form
- 1.3 Chemistry
  - 1.3.1 Compounds
2 History
3 Detection
- 3.1 Gamma counting
- 3.2 Alpha counting
4 Occurrence and production
- 4.1 Neutron capture
- 4.2 Proton capture
5 Applications
6 Biology and toxicity
- 6.1 Overview
- 6.2 Acute effects
- 6.3 Long term (chronic) effects
- 6.4 Regulatory exposure limits and handling
- 6.5 Well-known poisoning cases
- 6.6 Treatment
- 6.7 Detection in biological specimens
7 Commercial products containing polonium
- 7.1 Occurrence in humans and the biosphere
- 7.2 Tobacco
- 7.3 Food
8 See also
9 References
10 Bibliography
11 External links

Characteristics

Isotopes

Polonium has 33 known isotopes, all of which are radioactive. They have atomic masses that range from 188 to 220 u. ²¹⁰Po (half-life 138.376 days) is the most widely available. The longer-lived ²⁰⁹Po (half-life 125.2 ± 3.3 years, longest-lived of all polonium isotopes)^[2] and ²⁰⁸Po (half-life 2.9 years) can be made through the alpha, proton, or deuteron bombardment of lead or bismuth in a cyclotron.^[5]

²¹⁰Po is an alpha emitter that has a half-life of 138.4 days; it decays directly to its stable daughter isotope, ²⁰⁶Pb. A milligram (5 curies) of ²¹⁰Po emits about as many alpha particles per second as 5 grams of ²²⁶Ra.^[6] A few curies (1 curie equals 37 gigabecquerels, 1 Ci = 37 GBq) of ²¹⁰Po emit a blue glow which is caused by excitation of surrounding air.^{[citation needed]}

About one in 100,000 alpha emissions causes an excitation in the nucleus which then results in the emission of a gamma ray with a maximum energy of 803 keV.^[7]^[8]

Solid state form

The alpha form of solid polonium.

Polonium is a radioactive element that exists in two metallic allotropes. The alpha form is the only known example of a simple cubic crystal structure in a single atom basis, with an edge length of 335.2 picometers; the beta form is rhombohedral.^[9]^[10]^[11] The structure of polonium has been characterized by X-ray diffraction^[12]^[13] and electron diffraction.^[14]

²¹⁰Po (in common with ²³⁸Pu) has the ability to become airborne with ease: if a sample is heated in air to 55 °C (131 °F), 50% of it is vaporized in 45 hours to form diatomic Po₂ molecules, even though the melting point of polonium is 254 °C (489 °F) and its boiling point is 962 °C (1,764 °F).^[15]^[16]^[1] More than one hypothesis exists for how polonium does this; one suggestion is that small clusters of polonium atoms are spalled off by the alpha decay.

Chemistry

The chemistry of polonium is similar to that of tellurium and bismuth. Polonium dissolves readily in dilute acids, but is only slightly soluble in alkalis. Polonium solutions are first colored in pink by the Po²⁺ ions, but then rapidly become yellow because alpha radiation from polonium ionizes the solvent and converts Po²⁺ into Po⁴⁺. This process is accompanied by bubbling and emission of heat and light by glassware due to the absorbed alpha particles; as a result, polonium solutions are volatile and will evaporate within days unless sealed.^[17]^[18]

Compounds

Polonium has no common compounds, and almost all of its compounds are synthetically created; more than 50 of those are known.^[19] The most stable class of polonium compounds are polonides, which are prepared by direct reaction of two elements. Na₂Po has the antifluorite structure, the polonides of Ca, Ba, Hg, Pb and lanthanides form a NaCl lattice, BePo and CdPo have the wurtzite and MgPo the nickel arsenide structure. Most polonides decompose upon heating to about 600 °C, except for HgPo that decomposes at ~300 °C and the lanthanide polonides, which do not decompose but melt at temperatures above 1000 °C. For example, PrPo melts at 1250 °C and TmPo at 2200 °C.^[20] PbPo is one of the very few naturally occurring polonium compounds, as polonium alpha decays to form lead.^[21]

Polonium hydride (PoH
2) is a volatile liquid at room temperature prone to dissociation.^[20] The two oxides PoO₂ and PoO₃ are the products of oxidation of polonium.^[22]

Halides of the structure PoX₂, PoX₄ and PoX₆ are known. They are soluble in the corresponding hydrogen halides, i.e., PoCl_X in HCl, PoBr_X in HBr and PoI₄ in HI.^[23] Polonium dihalides are formed by direct reaction of the elements or by reduction of PoCl₄ with SO₂ and with PoBr₄ with H₂S at room temperature. Tetrahalides can be obtained by reacting polonium dioxide with HCl, HBr or HI.^[24]

Other polonium compounds include acetate, bromate, carbonate, citrate, chromate, cyanide, formate, hydroxide, nitrate, selenate, monosulfide, sulfate and disulfate.^[23]^[25]

Polonium compounds^[24]^[26]
Formula	Color	m.p. (°C)	Sublimation temp. (°C)	Symmetry	Pearson symbol	Space group	No	a (pm)	b(pm)	c(pm)	Z	ρ (g/cm³)	ref
PoO₂	pale yellow	500 (dec.)	885	fcc	cF12	Fm3m	225	563.7	563.7	563.7	4	8.94	^[27]
PoCl₂	dark red	355	130	orthorhombic	oP3	Pmmm	47	367	435	450	1	6.47	^[28]
PoBr₂	purple-brown	270 (dec.)											^[29]
PoCl₄	yellow	300	200	monoclinic									^[28]
PoBr₄	red	330 (dec.)		fcc	cF100	Fm3m	225	560	560	560	4		^[29]
PoI₄	black												^[30]

Oxides

PoO
PoO₂
PoO₃

Hydrides

PoH₂

Halides

PoX₂, e.g. polonium dichloride, PoCl₂
PoX₄, e.g. polonium tetrachloride, PoCl₄
PoF₆ (tentative)

History

Also tentatively called "radium F", polonium was discovered by Marie and Pierre Curie in 1898,^[31] and was named after Marie Curie's native land of Poland (Latin: Polonia).^[32]^[33] Poland at the time was under Russian, German, and Austro-Hungarian partition, and did not exist as an independent country. It was Curie's hope that naming the element after her native land would publicize its lack of independence.^[34] Polonium may be the first element named to highlight a political controversy.^[34]

This element was the first one discovered by the Curies while they were investigating the cause of pitchblende radioactivity. Pitchblende, after removal of the radioactive elements uranium and thorium, was more radioactive than the uranium and thorium combined. This spurred the Curies to search for additional radioactive elements. They first separated out polonium from pitchblende in July 1898, and five months later, also isolated radium.^[17]^[31]^[35]

In the United States, polonium was produced as part of the Manhattan Project's Dayton Project during World War II. It was a critical part of the implosion-type nuclear weapon design used in the Fat Man bomb on Nagasaki in 1945. Polonium and beryllium were the key ingredients of the 'urchin' detonator at the center of the bomb's spherical plutonium pit.^[36] The urchin ignited the nuclear chain reaction at the moment of prompt-criticality to ensure the bomb did not fizzle.^[36]

Much of the basic physics of polonium was classified until after the war. The fact that it was used as an initiator was classified until the 1960s.^[37]

The Atomic Energy Commission and the Manhattan Project funded human experiments using polonium on five people at the University of Rochester between 1943 and 1947. The people were administered between 9 and 22 microcuries (330 and 810 kBq) of polonium to study its excretion.^[38]^[39]^[40]

Detection

Emission intensity vs. photon energy for three polonium isotopes.

Gamma counting

By means of radiometric methods such as gamma spectroscopy (or a method using a chemical separation followed by an activity measurement with a non-energy-dispersive counter), it is possible to measure the concentrations of radioisotopes and to distinguish one from another. In practice, background noise would be present and depending on the detector, the line width would be larger which would make it harder to identify and measure the isotope. In biological/medical work it is common to use the natural ⁴⁰K present in all tissues/body fluids as a check of the equipment and as an internal standard.^[41]^[42]

Alpha counting

Emission intensity vs. alpha energy for four isotopes, note that the line width is narrow and the fine details can be seen.

The best way to test for (and measure) many alpha emitters is to use alpha-particle spectroscopy. It is common to place a drop of the test solution on a metal disk which is then dried out to give a uniform coating on the disk. This is then used as the test sample. If the thickness of the layer formed on the disk is too thick then the lines of the spectrum are broadened; this is because some of the energy of the alpha particles is lost during their movement through the layer of active material. An alternative method is to use internal liquid scintillation where the sample is mixed with a scintillation cocktail. When the light emitted is then counted, some machines will record the amount of light energy per radioactive decay event. Due to the imperfections of the liquid scintillation method (such as a failure of all the photons to be detected, cloudy or coloured samples can be difficult to count) and the fact that random quenching can reduce the number of photons generated per radioactive decay, it is possible to get a broadening of the alpha spectra obtained through liquid scintillation. It is likely that these liquid scintillation spectra will be subject to a Gaussian broadening rather than the distortion exhibited when the layer of active material on a disk is too thick.^[42]

A third energy dispersive method for counting alpha particles is to use a semiconductor detector.^[42]

From left to right the peaks are due to ²⁰⁹Po, ²¹⁰Po, ²³⁹Pu and ²⁴¹Am. The fact that isotopes such as ²³⁹Pu and ²⁴¹Am have more than one alpha line indicates that the nucleus has the ability to be in different discrete energy levels (like a molecule can).

Emission intensity vs. alpha energy for four isotopes, note that the line width is wide and some of the fine details can not be seen. This is for liquid scintillation counting where random effects cause a variation in the number of visible photons generated per alpha decay.

Occurrence and production

Polonium is a very rare element in nature because of the short half-life of all its isotopes. ²¹⁰Po, ²¹⁴Po, and ²¹⁸Po appear in the decay chain of ²³⁸U; thus polonium can be found in uranium ores at about 0.1 mg per metric ton (1 part in 10¹⁰),^[43]^[44] which is approximately 0.2% of the abundance of radium. The amounts in the Earth's crust are not harmful. Polonium has been found in tobacco smoke from tobacco leaves grown with phosphate fertilizers.^[45]^[46]^[47]

Because it is present in such small concentrations, isolation of polonium from natural sources is a very tedious process. The largest batch of the element ever extracted, performed in the first half of the 20th century, contained only 40 Ci (1.5 TBq) (9 mg) of polonium-210 and was obtained by processing 37 tonnes of residues from radium production.^[48] Polonium is now obtained by irradiating bismuth with high-energy neutrons or protons.^[17]^[49]

Neutron capture

Synthesis by (n,γ) reaction

In 1934, an experiment showed that when natural ²⁰⁹Bi is bombarded with neutrons, ²¹⁰Bi is created, which then decays to ²¹⁰Po via beta-minus decay. The final purification is done pyrochemically followed by liquid-liquid extraction techniques.^[50] Polonium may now be made in milligram amounts in this procedure which uses high neutron fluxes found in nuclear reactors.^[49] Only about 100 grams are produced each year, practically all of it in Russia, making polonium exceedingly rare.^[51]^[52]

This process can cause problems in lead-bismuth based liquid metal cooled nuclear reactors such as those used in the Soviet Navy's K-27. Measures must be taken in these reactors to deal with the unwanted possibility of ²¹⁰Po being released from the coolant.^[53]^[54]

Proton capture

Synthesis by (p,n) and (p,2n) reactions

It has been found that the longer-lived isotopes of polonium can be formed by proton bombardment of bismuth using a cyclotron. Other more neutron-rich isotopes can be formed by the irradiation of platinum with carbon nuclei.^[55]

Applications

Polonium-based sources of alpha particles were produced in the former Soviet Union.^[56] Such sources were applied for measuring the thickness of industrial coatings via attenuation of alpha radiation.^[57]

Because of intense alpha radiation, a one-gram sample of ²¹⁰Po will spontaneously heat up to above 500 °C (932 °F) generating about 140 watts of power. Therefore, ²¹⁰Po is used as an atomic heat source to power radioisotope thermoelectric generators via thermoelectric materials.^[6]^[17]^[58]^[59] For instance, ²¹⁰Po heat sources were used in the Lunokhod 1 (1970) and Lunokhod 2 (1973) Moon rovers to keep their internal components warm during the lunar nights, as well as the Kosmos 84 and 90 satellites (1965).^[56]^[60]

The alpha particles emitted by polonium can be converted to neutrons using beryllium oxide, at a rate of 93 neutrons per million alpha particles.^[58] Thus Po-BeO mixtures or alloys are used as a neutron source, for example in a neutron trigger or initiator for nuclear weapons^[17]^[61] and for inspections of oil wells. About 1500 sources of this type, with an individual activity of 1,850 Ci (68 TBq), have been used annually in the Soviet Union.^[62]

Polonium was also part of brushes or more complex tools that eliminate static charges in photographic plates, textile mills, paper rolls, sheet plastics, and on substrates (such as automotive) prior to the application of coatings. Alpha particles emitted by polonium ionize air molecules that neutralize charges on the nearby surfaces.^[63]^[64] Polonium needs to be replaced in these devices nearly every year because of its short half-life; it is also highly radioactive and therefore has been mostly replaced by less dangerous beta particle sources.^[6]

Tobacco smoke from cigarettes contains a small amount of polonium isotope 210, which can become deposited inside smokers' airways and deliver radiation directly to surrounding cells.

The lungs of smokers can be exposed to four times more polonium than those of non-smokers and specific parts may get a hundred times more radiation. One study estimated that someone smoking one and half packs a day receives the equivalent amount of radiation as someone having 300 chest X-rays a year.^[65]

Biology and toxicity

Overview

Polonium is highly dangerous and has no biological role.^[17] By mass, polonium-210 is around 250,000 times more toxic than hydrogen cyanide (the LD₅₀ for ²¹⁰Po is less than 1 microgram for an average adult (see below) compared with about 250 milligrams for hydrogen cyanide^[66]). The main hazard is its intense radioactivity (as an alpha emitter), which makes it very difficult to handle safely. Even in microgram amounts, handling ²¹⁰Po is extremely dangerous, requiring specialized equipment (a negative pressure alpha glove box equipped with high performance filters), adequate monitoring, and strict handling procedures to avoid any contamination. Alpha particles emitted by polonium will damage organic tissue easily if polonium is ingested, inhaled, or absorbed, although they do not penetrate the epidermis and hence are not hazardous as long as the alpha particles remain outside the body. Wearing chemically resistant and "intact" gloves is a mandatory precaution to avoid transcutaneous diffusion of polonium directly through the skin. Polonium delivered in concentrated nitric acid can easily diffuse through inadequate gloves (e.g., latex gloves) or the acid may damage the gloves.^[67]

It has been reported that some microbes can methylate polonium by the action of methylcobalamin.^[68]^[69] This is similar to the way in which mercury, selenium and tellurium are methylated in living things to create organometallic compounds. Studies investigating the metabolism of polonium-210 in rats have shown that only 0.002 to 0.009% of polonium-210 ingested is excreted as volatile polonium-210.^[70]

Acute effects

The median lethal dose (LD₅₀) for acute radiation exposure is generally about 4.5 Sv.^[71] The committed effective dose equivalent ²¹⁰Po is 0.51 µSv/Bq if ingested, and 2.5 µSv/Bq if inhaled.^[72] So a fatal 4.5 Sv dose can be caused by ingesting 8.8 MBq (240 µCi), about 50 nanograms (ng), or inhaling 1.8 MBq (49 µCi), about 10 ng. One gram of ²¹⁰Po could thus in theory poison 20 million people of whom 10 million would die. The actual toxicity of ²¹⁰Po is lower than these estimates, because radiation exposure that is spread out over several weeks (the biological half-life of polonium in humans is 30 to 50 days^[73]) is somewhat less damaging than an instantaneous dose. It has been estimated that a median lethal dose of ²¹⁰Po is 15 megabecquerels (0.41 mCi), or 0.089 micrograms, still an extremely small amount.^[74]^[75] For comparison, one grain of table salt is about 0,06 mg = 60 μg.[3]

Long term (chronic) effects

In addition to the acute effects, radiation exposure (both internal and external) carries a long-term risk of death from cancer of 5–10% per Sv.^[71] The general population is exposed to small amounts of polonium as a radon daughter in indoor air; the isotopes ²¹⁴Po and ²¹⁸Po are thought to cause the majority^[76] of the estimated 15,000–22,000 lung cancer deaths in the US every year that have been attributed to indoor radon.^[77] Tobacco smoking causes additional exposure to polonium.^[78]

Regulatory exposure limits and handling

The maximum allowable body burden for ingested ²¹⁰Po is only 1.1 kBq (30 nCi), which is equivalent to a particle massing only 6.8 picograms. The maximum permissible workplace concentration of airborne ²¹⁰Po is about 10 Bq/m³ (6990300000000000000♠3×10⁻¹⁰ µCi/cm³).^[79] The target organs for polonium in humans are the spleen and liver.^[80] As the spleen (150 g) and the liver (1.3 to 3 kg) are much smaller than the rest of the body, if the polonium is concentrated in these vital organs, it is a greater threat to life than the dose which would be suffered (on average) by the whole body if it were spread evenly throughout the body, in the same way as caesium or tritium (as T₂O).

²¹⁰Po is widely used in industry, and readily available with little regulation or restriction^{[citation needed]}. In the US, a tracking system run by the Nuclear Regulatory Commission was implemented in 2007 to register purchases of more than 16 curies (590 GBq) of polonium-210 (enough to make up 5,000 lethal doses). The IAEA "is said to be considering tighter regulations ... There is talk that it might tighten the polonium reporting requirement by a factor of 10, to 1.6 curies (59 GBq)."^[81] As of 2013, this is still the only alpha emitting byproduct material available, as a NRC Exempt Quantity, which may be held without a radioactive material license.^{[citation needed]}

Polonium and its compounds must be handled in a glove box, which is further enclosed in another box, maintained at a slightly higher pressure than the glove box to prevent the radioactive materials from leaking out. Gloves made of natural rubber do not provide sufficient protection against the radiation from polonium; surgical gloves are necessary. Neoprene gloves shield radiation from polonium better than natural rubber.^[82]

Well-known poisoning cases

The murder of Alexander Litvinenko, a Russian dissident, in 2006 was announced as due to ²¹⁰Po poisoning^[83]^[84] (see Alexander Litvinenko poisoning). According to Prof. Nick Priest of Middlesex University, an environmental toxicologist and radiation expert, speaking on Sky News on December 2, Litvinenko was probably the first person ever to die of the acute α-radiation effects of ²¹⁰Po.^[85]

Polonium administered to humans From 1943 to 1947; injected into 4 hospitalised patients, and orally given to a 5th. Studies such as this were funded by the Manhattan Project and the AEC, and conducted at the University of Rochester. The objective was to obtain data on human excretion of polonium to correlate with more extensive data from rats. Patients were selected as subjects as experimenters wanted persons who had not been exposed to polonium either through work or accident. All subjects had incurable diseases. Excretion of polonium was followed, and an autopsy was conducted at that time on the deceased patient to determine which organs absorbed the polonium. Patients' ages ranged from 'early thirties' to 'early forties.' The experiments were described in a Studies of polonium metabolism in human subjects, Chapter 3 of Biological Studies with Polonium, Radium, and Plutonium, National Nuclear Energy Series, Volume VI-3, McGraw-Hill, New York, 1950. Not specified is the isotope under study, but at the time was Polonium-210 was most readily available. The DoE factsheet submitted for this experiment reported no follow up on these subjects.^[86]

It has also been suggested that Irène Joliot-Curie was the first person to die from the radiation effects of polonium. She was accidentally exposed to polonium in 1946 when a sealed capsule of the element exploded on her laboratory bench. In 1956, she died from leukemia.^[87]

According to the book The Bomb in the Basement, several deaths in Israel during 1957–1969 were caused by ²¹⁰Po.^[88] A leak was discovered at a Weizmann Institute laboratory in 1957. Traces of ²¹⁰Po were found on the hands of professor Dror Sadeh, a physicist who researched radioactive materials. Medical tests indicated no harm, but the tests did not include bone marrow. Sadeh died from cancer. One of his students died of leukemia, and two colleagues died after a few years, both from cancer. The issue was investigated secretly, and there was never any formal admission that a connection between the leak and the deaths had existed.^[89]

Abnormally high concentrations of ²¹⁰Po were detected in July 2012 in clothes and personal belongings of the Palestinian leader Yasser Arafat, who died on 11 November 2004 of uncertain causes. The spokesman for the Institut de Radiophysique in Lausanne, Switzerland, where those items were analyzed, stressed that the "clinical symptoms described in Arafat's medical reports were not consistent with polonium-210 and that conclusions could not be drawn as to whether the Palestinian leader was poisoned or not", and that "the only way to confirm the findings would be to exhume Arafat's body to test it for polonium-210."^[90] On 27 November 2012 Arafat's body was exhumed and samples were taken for separate analysis by experts from France, Switzerland and Russia.^[91] On 12 October 2013, The Lancet published the group's finding that high levels of the element were found in Arafat's blood, urine, and in saliva stains on his clothes and toothbrush.^[92] The French tests later found some polonium but stated it was from "natural environmental origin."^[93] Following later Russian tests, in December 2013 Vladimir Uiba, the head of the Russian Federal Medical and Biological Agency, stated that Arafat died of natural causes and they had no plans to conduct further tests.^[93]

Treatment

It has been suggested that chelation agents such as British Anti-Lewisite (dimercaprol) can be used to decontaminate humans.^[94] In one experiment, rats were given a fatal dose of 1.45 MBq/kg (8.7 ng/kg) of ²¹⁰Po; all untreated rats were dead after 44 days, but 90% of the rats treated with the chelation agent HOEtTTC remained alive after 5 months.^[95]

Detection in biological specimens

Polonium-210 may be quantitated in biological specimens by alpha particle spectrometry to confirm a diagnosis of poisoning in hospitalized patients or to provide evidence in a medicolegal death investigation. The baseline urinary excretion of polonium-210 in healthy persons due to routine exposure to environmental sources is normally in a range of 5–15 mBq/day. Levels in excess of 30 mBq/day are suggestive of excessive exposure to the radionuclide.^[96]

Commercial products containing polonium

²¹⁰Po is manufactured in a nuclear reactor by bombarding ²⁰⁹Bi with neutrons. 100 grams are produced each year, almost all in Russia.^[97]

²¹⁰Po is contained in anti-static brushes, which are used in some printing presses.^[98] Some anti-static brushes contain up to 500 microcuries (20 MBq) of ²¹⁰Po as a source of charged particles for neutralizing static electricity.^[99] In USA, the devices with no more than 500 µCi (19 MBq) of (sealed) ²¹⁰Po per unit can be bought in any amount under a "general license",^[100] which means that a buyer need not be registered by any authorities.

Tiny amounts of such radioisotopes are sometimes used in the laboratory and for teaching purposes—typically of the order of 4–40 kBq (0.11–1.08 µCi), in the form of sealed sources, with the polonium deposited on a substrate or in a resin or polymer matrix—are often exempt from licensing by the NRC and similar authorities as they are not considered hazardous. Small amounts of ²¹⁰Po are manufactured for sale to the public in the United States as 'needle sources' for laboratory experimentation, and are retailed by scientific supply companies. The polonium is a layer of plating which in turn is plated with a material such as gold, which allows the alpha radiation (used in experiments such as cloud chambers) to pass while preventing the polonium from being released and presenting a toxic hazard. According to United Nuclear, they typically sell between four and eight sources per year.^[101]^[102]

Occurrence in humans and the biosphere

Polonium-210 is widespread in the biosphere, including in human tissues, because of its position in the uranium-238 decay chain. Natural uranium-238 in the Earth's crust decays through a series of solid radioactive intermediates including radium-226 to the radioactive gas radon-222, some of which, during its 3.8-day half-life, diffuses into the atmosphere. There it decays through several more steps to polonium-210, much of which, during its 138-day half-life, is washed back down to the Earth's surface, thus entering the biosphere, before finally decaying to stable lead-206.^[103]^[104]^[105]

As early as the 1920s Antoine Lacassagne, using polonium provided by his colleague Marie Curie, showed that the element has a very specific pattern of uptake in rabbit tissues, with high concentrations particularly in liver, kidney and testes.^[106] More recent evidence suggests that this behavior results from polonium substituting for sulfur in sulfur-containing amino-acids or related molecules^[107] and that similar patterns of distribution occur in human tissues.^[108] Polonium is indeed an element naturally present in all humans, contributing appreciably to natural background dose, with wide geographical and cultural variations, and particularly high levels in arctic residents, for example.^[109]

Tobacco

Polonium-210 in tobacco contributes to many of the cases of lung cancer worldwide. Most of this polonium is derived from lead-210 deposited on tobacco leaves from the atmosphere; the lead-210 is a product of radon-222 gas, much of which appears to originate from the decay of radium-226 from fertilizers applied to the tobacco soils.^[47]^[110]^[111]^[112]^[113]

The presence of polonium in tobacco smoke has been known since the early 1960s.^[114]^[115] Some of the world's biggest tobacco firms researched ways to remove the substance—to no avail—over a 40-year period but never published the results.^[47]

Food

Polonium is also found in the food chain, especially in seafood.^[116]^[117]

References

^ ^a ^b Thayer, John S. (2010). "Relativistic Effects and the Chemistry of the Heavier Main Group Elements". p. 78. doi:10.1007/978-1-4020-9975-5_2.
^ ^a ^b Boutin, Chad. "Polonium's Most Stable Isotope Gets Revised Half-Life Measurement". nist.gov. NIST Tech Beat. Retrieved 9 September 2014.
^ "Characterizing the Elements". Los Alamos National Laboratory. Retrieved 4 March 2013.
^ Hawkes, Stephen J. (2010). "Polonium and Astatine Are Not Semimetals". Journal of Chemical Education 87 (8): 783. Bibcode:2010JChEd..87..783H. doi:10.1021/ed100308w.
^ Emsley, John (2011). Nature's Building Blocks: An A-Z Guide to the Elements (New ed.). New York, NY: Oxford University Press. p. 415. ISBN 978-0-19-960563-7.
^ ^a ^b ^c "Polonium" (PDF). Argonne National Laboratory. Archived from the original (PDF) on 2007-07-03. Retrieved 2009-05-05.
^ Greenwood, p. 250
^ "210PO α decay". Nuclear Data Center, Korea Atomic Energy Research Institute. 2000. Retrieved 2009-05-05.
^ Greenwood, p. 753
^ Miessler, Gary L.; Tarr, Donald A. (2004). Inorganic Chemistry (3rd ed.). Upper Saddle River, N.J.: Pearson Prentice Hall. p. 285. ISBN 0-13-120198-0.
^ "The beta Po (A_i) Structure". Naval Research Laboratory. 2000-11-20. Archived from the original on 2001-02-04. Retrieved 2009-05-05.
^ Desando, R. J.; Lange, R. C. (1966). "The structures of polonium and its compounds—I α and β polonium metal". Journal of Inorganic and Nuclear Chemistry 28 (9): 1837–1846. doi:10.1016/0022-1902(66)80270-1.
^ Beamer, W. H.; Maxwell, C. R. (1946). "The Crystal Structure of Polonium". Journal of Chemical Physics 14 (9): 569. doi:10.1063/1.1724201.
^ Rollier, M. A.; Hendricks, S. B.; Maxwell, L. R. (1936). "The Crystal Structure of Polonium by Electron Diffraction". Journal of Chemical Physics 4 (10): 648. Bibcode:1936JChPh...4..648R. doi:10.1063/1.1749762.
^ Wąs, Bogdan; Misiak, Ryszard; Bartyzel, Mirosław; Petelenz, Barbara (2006). "Thermochromatographic Separation of ^206,208Po from a Bismuth Target Bombardet with Protons" (PDF). Nukleonica 51 (Suppl. 2): s3–s5.
^ Lide, D. R., ed. (2005). CRC Handbook of Chemistry and Physics (86th ed.). Boca Raton (FL): CRC Press. ISBN 0-8493-0486-5.
^ ^a ^b ^c ^d ^e ^f Emsley, John (2001). Nature's Building Blocks. New York: Oxford University Press. pp. 330–332. ISBN 0-19-850341-5.
^ Bagnall, p. 206
^ Bagnall, p. 199
^ ^a ^b Greenwood, p. 766
^ Weigel, F. (1959). "Chemie des Poloniums". Angewandte Chemie 71 (9): 289–316. doi:10.1002/ange.19590710902.
^ Holleman, A. F.; Wiberg, E. (2001). Inorganic Chemistry. San Diego: Academic Press. ISBN 0-12-352651-5.
^ ^a ^b Figgins, P. E. (1961) The Radiochemistry of Polonium, National Academy of Sciences, US Atomic Energy Commission, pp. 13–14 Google Books
^ ^a ^b Greenwood, pp. 765, 771, 775
^ Bagnall, pp. 212–226
^ Wiberg, Egon; Holleman, A. F. and Wiberg, Nils Inorganic Chemistry, Academic Press, 2001, p. 594, ISBN 0-12-352651-5.
^ Bagnall, K. W.; d'Eye, R. W. M. (1954). "The Preparation of Polonium Metal and Polonium Dioxide". J. Chem. Soc: 4295–4299. doi:10.1039/JR9540004295.
^ ^a ^b Bagnall, K. W.; d'Eye, R. W. M.; Freeman, J. H. (1955). "The polonium halides. Part I. Polonium chlorides". Journal of the Chemical Society (Resumed): 2320. doi:10.1039/JR9550002320.
^ ^a ^b Bagnall, K. W.; d'Eye, R. W. M.; Freeman, J. H. (1955). "The polonium halides. Part II. Bromides". Journal of the Chemical Society (Resumed): 3959. doi:10.1039/JR9550003959.
^ Bagnall, K. W.; d'Eye, R. W. M.; Freeman, J. H. (1956). "657. The polonium halides. Part III. Polonium tetraiodide". Journal of the Chemical Society (Resumed): 3385. doi:10.1039/JR9560003385.
^ ^a ^b Curie, P.; Curie, M. (1898). "Sur une substance nouvelle radio-active, contenue dans la pechblende" [On a new radioactive substance contained in pitchblende] (PDF). Comptes rendus (in French) 127: 175–178. English translation.
^ Pfützner, M. (1999). "Borders of the Nuclear World – 100 Years After Discovery of Polonium". Acta Physica Polonica B 30: 1197. Bibcode:1999AcPPB..30.1197P.
^ Adloff, J. P. (2003). "The centennial of the 1903 Nobel Prize for physics". Radichimica Acta 91 (12–2003): 681–688. doi:10.1524/ract.91.12.681.23428.
^ ^a ^b Kabzinska, K. (1998). "Chemical and Polish aspects of polonium and radium discovery". Przemysl Chemiczny 77 (3): 104–107.
^ Curie, P.; Curie, M.; Bémont, G. (1898). "Sur une nouvelle substance fortement radio-active contenue dans la pechblende" [On a new, strongly radioactive substance contained in pitchblende] (PDF). Comptes rendus (in French) 127: 1215–1217. English translation
^ ^a ^b Nuclear Weapons FAQ, Section 4.1, Version 2.04: 20 February 1999. Nuclearweaponarchive.org. Retrieved on 2013-04-28.
^ RESTRICTED DATA DECLASSIFICATION DECISIONS, 1946 TO THE PRESENT (RDD-7), January 1, 2001, U.S. Department of Energy Office of Declassification, via fas.org
^ American nuclear guinea pigs: three decades of radiation experiments on U.S. citizens. United States. Congress. House. of the Committee on Energy and Commerce. Subcommittee on Energy Conservation and Power, published by U.S. Government Printing Office, 1986, Identifier Y 4.En 2/3:99-NN, Electronic Publication Date 2010, at the University of Nevada, Reno, unr.edu
^ "Studies of polonium metabolism in human subjects", Chapter 3 in Biological Studies with Polonium, Radium, and Plutonium, National, Nuclear Energy Series, Volume VI-3, McGraw-Hill, New York, 1950, cited in "American Nuclear Guinea Pigs ...", 1986 House Energy and Commerce committee report
^ Moss, William and Eckhardt, Roger (1995) "The Human Plutonium Injection Experiments", Los Alamos Science, Number 23.
^ Gilmore G, Hemingway J. Practical Gamma-Ray Spectrometry. John Wiley & Sons, Chichester: 1995, ISBN 0-471-95150-1.
^ ^a ^b ^c Knoll G (2000) Radiation Detection and Measurement. John Wiley & Sons, Inc. NY:, ISBN 0-471-07338-5.
^ Greenwood, p. 746
^ Bagnall, p. 198
^ Kilthau, Gustave F (1996). "Cancer risk in relation to radioactivity in tobacco". Radiologic Technology 67 (3): 217–222. PMID 8850254.
^ "Alpha Radioactivity (210 Polonium) and Tobacco Smoke". Retrieved 2009-05-05.
^ ^a ^b ^c Monique, E. Muggli; Ebbert, Jon O.; Robertson, Channing; Hurt, Richard D. (2008). "Waking a Sleeping Giant: The Tobacco Industry's Response to the Polonium-210 Issue". American Journal of Public Health 98 (9): 1643–50. doi:10.2105/AJPH.2007.130963. PMC 2509609. PMID 18633078.
^ Adloff, J. P. & MacCordick, H. J. (1995). "The Dawn of Radiochemistry". Radiochimica Acta. 70/71: 13–22. , reprinted in Adloff, J.P (1996). One hundred years after the discovery of radioactivity. p. 17. ISBN 978-3-486-64252-0.
^ ^a ^b Greenwood, p. 249
^ Schulz, Wallace W.; Schiefelbein, Gary F.; Bruns, Lester E. (1969). "Pyrochemical Extraction of Polonium from Irradiated Bismuth Metal". Ind. Eng. Chem. Process Des. Dev. 8 (4): 508–515. doi:10.1021/i260032a013.
^ "Q&A: Polonium-210". RSC Chemistry World. 2006-11-27. Retrieved 2009-01-12.
^ "Most Polonium Made Near the Volga River". The St. Petersburg Times – News. 2001-01-23.
^ Long-lived radionuclides of sodium, lead-bismuth, and lead coolants in fast-neutron reactors, Atomic Energy, Volume 87, Number 3 (1999), 658–662, DOI: 10.1007/BF02673579, V. I. Usanov, D. V. Pankratov, É. P. Popov, P. I. Markelov, L. D. Ryabaya and S. V. Zabrodskaya
^ Naumov, V. V. (November 2006). За какими корабельными реакторами будущее?. Атомная стратегия (in Russian) 26.
^ Atterling, H.; Forsling, W. (1959). "Light Polonium Isotopes from Carbon Ion Bombardments of Platinum". Arkiv for Fysik 15 (1): 81–88. OSTI 4238755.
^ ^a ^b Радиоизотопные источники тепла at the Wayback Machine (archived September 17, 2008) (in Russian). npc.sarov.ru
^ Bagnall, p. 225
^ ^a ^b Greenwood, p. 251
^ Hanslmeier, Arnold (2002). The sun and space weather. Springer. p. 183. ISBN 1-4020-0684-5.
^ Wilson, Andrew (1987). Solar System Log. London: Jane's Publishing Company Ltd. p. 64. ISBN 0-7106-0444-0.
^ Rhodes, Richard (2002). Dark Sun: The Making of the Hydrogen Bomb. New York: Walker & Company. pp. 187–188. ISBN 0-684-80400-X.
^ Красивая версия "самоубийства" Литвиненко вследствие криворукости (in Russian). stringer.ru (2006-11-26).
^ "Static Control for Electronic Balance Systems" (PDF). Retrieved 2009-05-05.
^ "BBC News : College breaches radioactive regulations". 2002-03-12. Retrieved 2009-05-05.
^ "Smoking and cancer: What's in a cigarette?". cancerresearchuk.org.
^ "Safety data for hydrogen cyanide". Physical & Theoretical Chemistry Lab, Oxford University. Archived from the original on 2002-02-11.
^ Bagnall, pp. 202–6
^ Momoshima, N.; Song, L.X.; Osaki, S.; Maeda, Y. (2001). "Formation and emission of volatile polonium compound by microbial activity and polonium methylation with methylcobalamin". Environ Sci Technol 35 (15): 2956–2960. doi:10.1021/es001730.
^ Momoshima, N.; Song, L.X.; Osaki, S.; Maeda, Y. (2002). "Biologically induced Po emission from fresh water". J Environ Radioact 63 (2): 187–197. doi:10.1016/S0265-931X(02)00028-0.
^ Li, Chunsheng; Sadi, Baki; Wyatt, Heather; Bugden, Michelle et al. (2010). "Metabolism of ²¹⁰Po in rats: volatile ²¹⁰Po in excreta". Radiation Protection Dosimetry (Oxford University Press) 140 (2): 158–162. doi:10.1093/rpd/ncq047. PMID 20159915. Retrieved 2013-04-09.
^ ^a ^b "Health Impacts from Acute Radiation Exposure" (PDF). Pacific Northwest National Laboratory. Retrieved 2009-05-05.
^ "Nuclide Safety Data Sheet: Polonium–210" (PDF). hpschapters.org. Retrieved 2009-05-05.
^ Naimark, D.H. (1949-01-04). "Effective half-life of polonium in the human". Technical Report MLM-272/XAB, Mound Lab., Miamisburg, OH. OSTI 7162390.
^ "Polonium Poisoning". Retrieved 2009-05-05.
^ Harrison, J.; Leggett, Rich; Lloyd, David; Phipps, Alan et al. (2007). "Polonium-210 as a poison". J. Radiol. Prot. 27 (1): 17–40. Bibcode:2007JRP....27...17H. doi:10.1088/0952-4746/27/1/001. PMID 17341802. The conclusion is reached that 0.1–0.3 GBq or more absorbed to blood of an adult male is likely to be fatal within 1 month. This corresponds to ingestion of 1–3 GBq or more, assuming 10% absorption to blood
^ Health Risks of Radon and Other Internally Deposited Alpha-Emitters: BEIR IV. National Academy Press. 1988. p. 5. ISBN 0-309-03789-1.
^ Health Effects Of Exposure To Indoor Radon. Washington: National Academy Press. 1999. Archived from the original on 2006-09-19.
^ "The Straight Dope: Does smoking organically grown tobacco lower the chance of lung cancer?". Retrieved 2009-05-05.
^ "Nuclear Regulatory Commission limits for ²¹⁰Po". U.S. NRC. 2008-12-12. Retrieved 2009-01-12.
^ "PilgrimWatch – Pilgrim Nuclear – Health Impact". Retrieved 2009-05-05.
^ Zimmerman, Peter D. (2006-12-19). "The Smoky Bomb Threat". The New York Times. Retrieved 2006-12-19.
^ Bagnall, p. 204
^ Geoghegan, Tom (2006-11-24). "The mystery of Litvinenko's death". BBC News.
^ "UK requests Lugovoi extradition". BBC News. 2007-05-28. Retrieved 2009-05-05.
^ Watson, Roland (2006-12-03). "Focus: Cracking the code of the nuclear assassin". The Sunday Times (London). Archived from the original on 2008-02-10. Retrieved 2010-05-22.
^ "American nuclear guinea pigs : three decades of radiation experiments on U.S. citizens". Retrieved 2015-06-09.
^ Manier, Jeremy (2006-12-04). "Innocent chemical a killer". The Daily Telegraph (Australia). Retrieved 2009-05-05.
^ Karpin, Michael (2006). The bomb in the basement: How Israel went nuclear and what that means for the world. Simon and Schuster. ISBN 0-7432-6594-7.
^ Maugh, Thomas; Karen Kaplan (2007-01-01). "A restless killer radiates intrigue". Los Angeles Times. Retrieved 2008-09-17.
^ Bart, Katharina (2012-07-03). Swiss institute finds polonium in Arafat's effects. Reuters.
^ "Experts exhume Arafat, seek evidence of poison". Reuters. 2012-11-27. Retrieved 2012-11-27.
^ Froidevaux, P.; Baechler, S. B.; Bailat, C. J.; Castella, V.; Augsburger, M.; Michaud, K.; Mangin, P.; Bochud, F. O. O. (2013). "Improving forensic investigation for polonium poisoning". The Lancet 382 (9900): 1308. doi:10.1016/S0140-6736(13)61834-6. edit
^ ^a ^b Isachenkov, Vadim (2013-12-27) Russia: Arafat's death not caused by radiation. Associated Press.
^ "Guidance for Industry. Internal Radioactive Contamination — Development of Decorporation Agents" (PDF). US Food and Drug Administration. Retrieved 2009-07-07.
^ Rencováa J.; Svoboda V.; Holuša R.; Volf V. et al. (1997). "Reduction of subacute lethal radiotoxicity of polonium-210 in rats by chelating agents". International Journal of Radiation Biology 72 (3): 247. doi:10.1080/095530097143338.
^ Baselt, R. Disposition of Toxic Drugs and Chemicals in Man, 10th edition, Biomedical Publications, Seal Beach, CA.
^ "Swiss study: Polonium found in Arafat’s bones". Al Jazeera. 2013-11-06. Archived from the original on 2013-11-06.
^ Boice, John D.; Cohen, Sarah S. et al. (2014). "Mortality Among Mound Workers Exposed to Polonium-210 and Other Sources of Radiation, 1944–1979". Radiation Research 181 (2): 140214120928006. doi:10.1667/RR13395.1. ISSN 0033-7587.
^ "Staticmaster Ionizing Brushes". AMSTAT Industries. Retrieved 2009-05-05.
^ "General domestic licenses for byproduct material". Retrieved 2009-05-05.
^ Singleton, Don (2006-11-28). "The Availability of polonium-210". Retrieved 2006-11-29.
^ "Radioactive Isotopes". United Nuclear. Retrieved 2007-03-19.
^ Hill, C. R. (1960). "Lead-210 and Polonium-210 in Grass". Nature 187 (4733): 211–212. Bibcode:1960Natur.187..211H. doi:10.1038/187211a0.
^ Hill, C.R. (1963). "Natural occurrence of unsupported radium-F (Po-210) in tissue". Health Physics (9): 952–953.
^ Heyraud, M.; Cherry, R. D. (1979). "Polonium-210 and lead-210 in marine food chains". Marine Biology 52 (3): 227–236. doi:10.1007/BF00398136.
^ Lacassagne, A. & Lattes, J. (1924) Bulletin d'Histologie Appliquée à la Physiologie et à la Pathologie, 1, 279.
^ Vasken Aposhian, H.; Bruce, D. C. (1991). "Binding of Polonium-210 to Liver Metallothionein". Radiation Research 126 (3): 379–382. doi:10.2307/3577929. JSTOR 3577929. PMID 2034794.
^ Hill, CR (1965). "Polonium-210 in man". Nature 208 (5009): 423–8. Bibcode:1965Natur.208..423H. doi:10.1038/208423a0. PMID 5867584.
^ Hill, C. R. (1966). "Polonium-210 Content of Human Tissues in Relation to Dietary Habit". Science 152 (3726): 1261–2. Bibcode:1966Sci...152.1261H. doi:10.1126/science.152.3726.1261. PMID 5949242.
^ Martell, E. A. (1974). "Radioactivity of tobacco trichomes and insoluble cigarette smoke particles". Nature 249 (5454): 214–217. Bibcode:1974Natur.249..215M. doi:10.1038/249215a0. Retrieved 20 July 2014.
^ Martell, E. A. (1975). "Tobacco Radioactivity and Cancer in Smokers: Alpha interactions with chromosomes of cells surrounding insoluble radioactive smoke particles may cause cancer and contribute to early atherosclerosis development in cigarette smokers". American Scientist 63 (4): 404–412. Bibcode:1975AmSci..63..404M. JSTOR 27845575. PMID 1137236.
^ Journal of the Royal Society of Medicine, The big idea: polonium, radon and cigarettes, Tidd J R Soc Med.2008; 101: 156–157 [1]
^ The Age Melbourne Australia, Big Tobacco covered up radiation danger, William Birnbauer [2]
^ Radford EP Jr; Hunt VR (1964). "Polonium 210: a volatile radioelement in cigarettes". Science 143 (3603): 247–9. Bibcode:1964Sci...143..247R. doi:10.1126/science.143.3603.247. PMID 14078362.
^ Kelley TF (1965). "Polonium 210 content of mainstream cigarette smoke". Science 149 (3683): 537–538. Bibcode:1965Sci...149..537K. doi:10.1126/science.149.3683.537.
^ Ota, Tomoko; Sanada, Tetsuya; Kashiwara, Yoko; Morimoto, Takao et al. (2009). "Evaluation for Committed Effective Dose Due to Dietary Foods by the Intake for Japanese Adults". Japanese Journal of Health Physics 44: 80–88. doi:10.5453/jhps.44.80.
^ Smith-Briggs, JL; Bradley, EJ (1984). "Measurement of natural radionuclides in U.K. diet". Science of the Total Environment 35 (3): 431–40. doi:10.1016/0048-9697(84)90015-9. PMID 6729447.

Bibliography

Bagnall, K. W. (1962). "The Chemistry of Polonium". Advances in Inorganic Chemistry and Radiochemistry 4. New York: Academic Press. pp. 197–226. doi:10.1016/S0065-2792(08)60268-X. ISBN 0-12-023604-4. Retrieved June 14, 2012.
Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth–Heinemann. ISBN 0080379419.

External links

Chemistry in its element podcast (MP3) from the Royal Society of Chemistry's Chemistry World: Polonium
Polonium at The Periodic Table of Videos (University of Nottingham)

UpToDate Contents

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1. 成人における放射線障害の生物学および臨床的特徴 biology and clinical features of radiation injury in adults

English Journal

Optimization of low-background alpha spectrometers for analysis of thick samples.

Misiaszek M, Pelczar K, Wójcik M, Zuzel G, Laubenstein M.SourceM. Smoluchowski Institute of Physics, Jagiellonian University, Reymonta 4, PL-30-059 Kraków, Poland.
Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine.Appl Radiat Isot.2013 Nov;81:146-50. doi: 10.1016/j.apradiso.2013.03.006. Epub 2013 Mar 16.
Results of alpha spectrometric measurements performed deep underground and above ground with and without active veto show that the underground measurement of thick samples is the most sensitive method due to significant reduction of the muon-induced background. In addition, the polonium diffusion re
PMID 23628514

Comparison of various dissolution techniques for determination of Po-210 in biological samples.

Planinšek P, Benedik L, Smodiš B.SourceJožef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia.
Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine.Appl Radiat Isot.2013 Nov;81:53-6. doi: 10.1016/j.apradiso.2013.03.008. Epub 2013 Mar 21.
The aim of the present study was to compare three wet digestion procedures for dissolution of biological samples in the determination of Po-210. Classical wet ashing over a gas flame with acids in a long-necked Kjeldahl flask, digestion with acids in an Erlenmeyer flask and microwave digestion in a
PMID 23562435

Seasonal and spatial variations of (210)Po and (210)Pb activity concentrations in Mytilus galloprovincialis from Croatian coast of the Adriatic Sea.

Rožmarić M, Rogić M, Benedik L, Strok M, Barišić D.SourceRudjer Boskovic Institute, Bijenicka cesta 54, 10000 Zagreb, Croatia; Environment Laboratories, International Atomic Energy Agency, 4 Quai Antoine 1er, MC 98000, Monaco. Electronic address: rozmar@irb.hr.
Chemosphere.Chemosphere.2013 Nov;93(9):2063-8. doi: 10.1016/j.chemosphere.2013.07.039. Epub 2013 Aug 9.
Results of 2years monitoring of (210)Po and (210)Pb activity concentrations in soft tissue of the species Mytilus galloprovincialis from Croatian part of the Adriatic coast are presented. The samples were collected at thirteen coastal stations (some of which are also a part of the Mediterranean Muss
PMID 23932819

Occurrence of 210Po in periwinkle (Littorina undulata, Gray, 1839) collected from Kudankulam (Gulf of Mannar (GOM), Southeast coast of India).

Sunith Shine SR, Feroz Khan M, Godwin Wesley S.SourceDivision of Marine Biotechnology, Vizhinjam Research Centre, Central Marine Fisheries Research Institute (CMFRI), Vizhinjam, Kerala 695 221, India.
Marine pollution bulletin.Mar Pollut Bull.2013 Oct 15;75(1-2):276-82. doi: 10.1016/j.marpolbul.2013.06.047. Epub 2013 Jul 17.
Polonium-210 activity concentration was analysed in the whole body tissue of periwinkle Littorina undulata collected from intertidal rocky shore along Kudankulam coast. We carried out the study for a period of 12 months (2011-2012) focusing on three seasons. (210)Po was found non-uniformly distribut
PMID 23871576

Japanese Journal

キュリー家(マリー、ピエール、ジャック)の放射能研究と放射線測定

西尾成子,高田誠二
計量史研究 35(1), 19-26, 2013-02-10
NAID 110009594252

キュリー家(マリー、ピエール、ジャック)の放射能研究と放射線測定

西尾成子,高田誠二
計量史研究 = Bulletin of the Society of Hist[o]rical Metrology, Japan 35(1), 19-26, 2013-02-10
NAID 10031180043

International Topical Conference of Polonium and Radioactive Lead Isotopes 印象記

廣瀬勝己
Isotope news (672), 20-21, 2010-04-01
NAID 10026800142

Improvements on the method for determining of 210Pb and 210Po in lead

Uesugi Masaki,Noguchi Masayasu,Yokoyama Akihiko
Journal of Radioanalytical and Nuclear Chemistry 283(3), 577-584, 2010-03
… To selectively extract polonium from an alkaline solution, the pH dependency was examined using a liquid scintillation counting method. …
NAID 120002224333

「Po」

Polonium, ₈₄Po
General properties
Name, symbol	polonium, Po
Pronunciation	/pɵˈloʊniəm/; po-LOH-nee-əm
Allotropes	α, β
Appearance	silvery
Polonium in the periodic table
	bismuth ← polonium → astatine
Atomic number	84
Standard atomic weight (Ar)	(209)
Element category	post-transition metal, but this status is disputed
Group, block	group 16 (chalcogens), p-block
Period	period 6
Electron configuration	[Xe] 4f14 5d10 6s2 6p4
per shell	2, 8, 18, 32, 18, 6
Physical properties
Phase	solid
Melting point	527 K (254 °C, 489 °F)
Boiling point	1235 K (962 °C, 1764 °F)
Density near r.t.	alpha: 9.196 g/cm3; beta: 9.398 g/cm3
Heat of fusion	ca. 13 kJ/mol
Heat of vaporization	102.91 kJ/mol
Molar heat capacity	26.4 J/(mol·K)
Atomic properties
Oxidation states	6, 5, 4, 2, −2 (an amphoteric oxide)
Electronegativity	Pauling scale: 2.0
Ionization energies	1st: 812.1 kJ/mol
Atomic radius	empirical: 168 pm
Covalent radius	140±4 pm
Van der Waals radius	197 pm
Miscellanea
Crystal structure	cubic ; α-Po
Crystal structure	rhombohedral ; β-Po
Thermal expansion	23.5 µm/(m·K) (at 25 °C)
Thermal conductivity	20 W/(m·K) (?)
Electrical resistivity	α: 0.40 µΩ·m (at 0 °C)
Magnetic ordering	nonmagnetic
CAS Registry Number	7440-08-6
History
Naming	after Polonia, Latin for Poland. Homeland of one of the discoverers
Discovery	Pierre Curie and Marie Curie (1898)
First isolation	Willy Marckwald (1902)
Most stable isotopes
	Main article: Isotopes of polonium
	view; talk; edit; · references

　　[★] ポロニウム polonium 　　

[Thayer-1] Thayer, John S. (2010). "Relativistic Effects and the Chemistry of the Heavier Main Group Elements". p. 78. doi:10.1007/978-1-4020-9975-5_2.

[Po209-2] Boutin, Chad. "Polonium's Most Stable Isotope Gets Revised Half-Life Measurement". nist.gov. NIST Tech Beat. Retrieved 9 September 2014.

[3] "Characterizing the Elements". Los Alamos National Laboratory. Retrieved 4 March 2013.

[4] Hawkes, Stephen J. (2010). "Polonium and Astatine Are Not Semimetals". Journal of Chemical Education 87 (8): 783. Bibcode:2010JChEd..87..783H. doi:10.1021/ed100308w.

[emsley-5] Emsley, John (2011). Nature's Building Blocks: An A-Z Guide to the Elements (New ed.). New York, NY: Oxford University Press. p. 415. ISBN 978-0-19-960563-7.

[anl-6] "Polonium" (PDF). Argonne National Laboratory. Archived from the original (PDF) on 2007-07-03. Retrieved 2009-05-05.

[7] Greenwood, p. 250

[8] "210PO α decay". Nuclear Data Center, Korea Atomic Energy Research Institute. 2000. Retrieved 2009-05-05.

[9] Greenwood, p. 753

[10] Miessler, Gary L.; Tarr, Donald A. (2004). Inorganic Chemistry (3rd ed.). Upper Saddle River, N.J.: Pearson Prentice Hall. p. 285. ISBN 0-13-120198-0.

[11] "The beta Po (A_i) Structure". Naval Research Laboratory. 2000-11-20. Archived from the original on 2001-02-04. Retrieved 2009-05-05.

[12] Desando, R. J.; Lange, R. C. (1966). "The structures of polonium and its compounds—I α and β polonium metal". Journal of Inorganic and Nuclear Chemistry 28 (9): 1837–1846. doi:10.1016/0022-1902(66)80270-1.

[13] Beamer, W. H.; Maxwell, C. R. (1946). "The Crystal Structure of Polonium". Journal of Chemical Physics 14 (9): 569. doi:10.1063/1.1724201.

[14] Rollier, M. A.; Hendricks, S. B.; Maxwell, L. R. (1936). "The Crystal Structure of Polonium by Electron Diffraction". Journal of Chemical Physics 4 (10): 648. Bibcode:1936JChPh...4..648R. doi:10.1063/1.1749762.

[15] Wąs, Bogdan; Misiak, Ryszard; Bartyzel, Mirosław; Petelenz, Barbara (2006). "Thermochromatographic Separation of ^206,208Po from a Bismuth Target Bombardet with Protons" (PDF). Nukleonica 51 (Suppl. 2): s3–s5.

[CRC-16] Lide, D. R., ed. (2005). CRC Handbook of Chemistry and Physics (86th ed.). Boca Raton (FL): CRC Press. ISBN 0-8493-0486-5.

[nbb-17] ^ ^a ^b ^c ^d ^e ^f Emsley, John (2001). Nature's Building Blocks. New York: Oxford University Press. pp. 330–332. ISBN 0-19-850341-5.

[18] Bagnall, p. 206

[19] Bagnall, p. 199

[g766-20] Greenwood, p. 766

[21] Weigel, F. (1959). "Chemie des Poloniums". Angewandte Chemie 71 (9): 289–316. doi:10.1002/ange.19590710902.

[22] Holleman, A. F.; Wiberg, E. (2001). Inorganic Chemistry. San Diego: Academic Press. ISBN 0-12-352651-5.

[figgins-23] Figgins, P. E. (1961) The Radiochemistry of Polonium, National Academy of Sciences, US Atomic Energy Commission, pp. 13–14 Google Books

[g765-24] Greenwood, pp. 765, 771, 775

[25] Bagnall, pp. 212–226

[26] Wiberg, Egon; Holleman, A. F. and Wiberg, Nils Inorganic Chemistry, Academic Press, 2001, p. 594, ISBN 0-12-352651-5.

[Bagnall-27] Bagnall, K. W.; d'Eye, R. W. M. (1954). "The Preparation of Polonium Metal and Polonium Dioxide". J. Chem. Soc: 4295–4299. doi:10.1039/JR9540004295.

[PoCl-28] Bagnall, K. W.; d'Eye, R. W. M.; Freeman, J. H. (1955). "The polonium halides. Part I. Polonium chlorides". Journal of the Chemical Society (Resumed): 2320. doi:10.1039/JR9550002320.

[PoBr-29] Bagnall, K. W.; d'Eye, R. W. M.; Freeman, J. H. (1955). "The polonium halides. Part II. Bromides". Journal of the Chemical Society (Resumed): 3959. doi:10.1039/JR9550003959.

[30] Bagnall, K. W.; d'Eye, R. W. M.; Freeman, J. H. (1956). "657. The polonium halides. Part III. Polonium tetraiodide". Journal of the Chemical Society (Resumed): 3385. doi:10.1039/JR9560003385.

[c1-31] Curie, P.; Curie, M. (1898). "Sur une substance nouvelle radio-active, contenue dans la pechblende" [On a new radioactive substance contained in pitchblende] (PDF). Comptes rendus (in French) 127: 175–178. English translation.

[32] Pfützner, M. (1999). "Borders of the Nuclear World – 100 Years After Discovery of Polonium". Acta Physica Polonica B 30: 1197. Bibcode:1999AcPPB..30.1197P.

[33] Adloff, J. P. (2003). "The centennial of the 1903 Nobel Prize for physics". Radichimica Acta 91 (12–2003): 681–688. doi:10.1524/ract.91.12.681.23428.

[Przemysl-34] Kabzinska, K. (1998). "Chemical and Polish aspects of polonium and radium discovery". Przemysl Chemiczny 77 (3): 104–107.

[c2-35] Curie, P.; Curie, M.; Bémont, G. (1898). "Sur une nouvelle substance fortement radio-active contenue dans la pechblende" [On a new, strongly radioactive substance contained in pitchblende] (PDF). Comptes rendus (in French) 127: 1215–1217. English translation

[nwfaq41-36] Nuclear Weapons FAQ, Section 4.1, Version 2.04: 20 February 1999. Nuclearweaponarchive.org. Retrieved on 2013-04-28.

[37] RESTRICTED DATA DECLASSIFICATION DECISIONS, 1946 TO THE PRESENT (RDD-7), January 1, 2001, U.S. Department of Energy Office of Declassification, via fas.org

[congress1986-38] American nuclear guinea pigs: three decades of radiation experiments on U.S. citizens. United States. Congress. House. of the Committee on Energy and Commerce. Subcommittee on Energy Conservation and Power, published by U.S. Government Printing Office, 1986, Identifier Y 4.En 2/3:99-NN, Electronic Publication Date 2010, at the University of Nevada, Reno, unr.edu

[nes1950-39] "Studies of polonium metabolism in human subjects", Chapter 3 in Biological Studies with Polonium, Radium, and Plutonium, National, Nuclear Energy Series, Volume VI-3, McGraw-Hill, New York, 1950, cited in "American Nuclear Guinea Pigs ...", 1986 House Energy and Commerce committee report

[40] Moss, William and Eckhardt, Roger (1995) "The Human Plutonium Injection Experiments", Los Alamos Science, Number 23.

[Gilmore-41] Gilmore G, Hemingway J. Practical Gamma-Ray Spectrometry. John Wiley & Sons, Chichester: 1995, ISBN 0-471-95150-1.

[Knoll-42] Knoll G (2000) Radiation Detection and Measurement. John Wiley & Sons, Inc. NY:, ISBN 0-471-07338-5.

[43] Greenwood, p. 746

[44] Bagnall, p. 198

[45] Kilthau, Gustave F (1996). "Cancer risk in relation to radioactivity in tobacco". Radiologic Technology 67 (3): 217–222. PMID 8850254.

[46] "Alpha Radioactivity (210 Polonium) and Tobacco Smoke". Retrieved 2009-05-05.

[Muggli08-47] Monique, E. Muggli; Ebbert, Jon O.; Robertson, Channing; Hurt, Richard D. (2008). "Waking a Sleeping Giant: The Tobacco Industry's Response to the Polonium-210 Issue". American Journal of Public Health 98 (9): 1643–50. doi:10.2105/AJPH.2007.130963. PMC 2509609. PMID 18633078.

[48] Adloff, J. P. & MacCordick, H. J. (1995). "The Dawn of Radiochemistry". Radiochimica Acta. 70/71: 13–22. , reprinted in Adloff, J.P (1996). One hundred years after the discovery of radioactivity. p. 17. ISBN 978-3-486-64252-0.

[g249-49] Greenwood, p. 249

[50] Schulz, Wallace W.; Schiefelbein, Gary F.; Bruns, Lester E. (1969). "Pyrochemical Extraction of Polonium from Irradiated Bismuth Metal". Ind. Eng. Chem. Process Des. Dev. 8 (4): 508–515. doi:10.1021/i260032a013.

[51] "Q&A: Polonium-210". RSC Chemistry World. 2006-11-27. Retrieved 2009-01-12.

[52] "Most Polonium Made Near the Volga River". The St. Petersburg Times – News. 2001-01-23.

[53] Long-lived radionuclides of sodium, lead-bismuth, and lead coolants in fast-neutron reactors, Atomic Energy, Volume 87, Number 3 (1999), 658–662, DOI: 10.1007/BF02673579, V. I. Usanov, D. V. Pankratov, É. P. Popov, P. I. Markelov, L. D. Ryabaya and S. V. Zabrodskaya

[54] Naumov, V. V. (November 2006). За какими корабельными реакторами будущее?. Атомная стратегия (in Russian) 26.

[55] Atterling, H.; Forsling, W. (1959). "Light Polonium Isotopes from Carbon Ion Bombardments of Platinum". Arkiv for Fysik 15 (1): 81–88. OSTI 4238755.

[rus1-56] Радиоизотопные источники тепла at the Wayback Machine (archived September 17, 2008) (in Russian). npc.sarov.ru

[57] Bagnall, p. 225

[g251-58] Greenwood, p. 251

[59] Hanslmeier, Arnold (2002). The sun and space weather. Springer. p. 183. ISBN 1-4020-0684-5.

[60] Wilson, Andrew (1987). Solar System Log. London: Jane's Publishing Company Ltd. p. 64. ISBN 0-7106-0444-0.

[61] Rhodes, Richard (2002). Dark Sun: The Making of the Hydrogen Bomb. New York: Walker & Company. pp. 187–188. ISBN 0-684-80400-X.

[62] Красивая версия "самоубийства" Литвиненко вследствие криворукости (in Russian). stringer.ru (2006-11-26).

[63] "Static Control for Electronic Balance Systems" (PDF). Retrieved 2009-05-05.

[64] "BBC News : College breaches radioactive regulations". 2002-03-12. Retrieved 2009-05-05.

[65] "Smoking and cancer: What's in a cigarette?". cancerresearchuk.org.

[66] "Safety data for hydrogen cyanide". Physical & Theoretical Chemistry Lab, Oxford University. Archived from the original on 2002-02-11.

[67] Bagnall, pp. 202–6

[68] Momoshima, N.; Song, L.X.; Osaki, S.; Maeda, Y. (2001). "Formation and emission of volatile polonium compound by microbial activity and polonium methylation with methylcobalamin". Environ Sci Technol 35 (15): 2956–2960. doi:10.1021/es001730.

[69] Momoshima, N.; Song, L.X.; Osaki, S.; Maeda, Y. (2002). "Biologically induced Po emission from fresh water". J Environ Radioact 63 (2): 187–197. doi:10.1016/S0265-931X(02)00028-0.

[70] Li, Chunsheng; Sadi, Baki; Wyatt, Heather; Bugden, Michelle et al. (2010). "Metabolism of ²¹⁰Po in rats: volatile ²¹⁰Po in excreta". Radiation Protection Dosimetry (Oxford University Press) 140 (2): 158–162. doi:10.1093/rpd/ncq047. PMID 20159915. Retrieved 2013-04-09.

[pnl-71] "Health Impacts from Acute Radiation Exposure" (PDF). Pacific Northwest National Laboratory. Retrieved 2009-05-05.

[nsds-72] "Nuclide Safety Data Sheet: Polonium–210" (PDF). hpschapters.org. Retrieved 2009-05-05.

[73] Naimark, D.H. (1949-01-04). "Effective half-life of polonium in the human". Technical Report MLM-272/XAB, Mound Lab., Miamisburg, OH. OSTI 7162390.

[nuclearweaponsarchive-74] "Polonium Poisoning". Retrieved 2009-05-05.

[75] Harrison, J.; Leggett, Rich; Lloyd, David; Phipps, Alan et al. (2007). "Polonium-210 as a poison". J. Radiol. Prot. 27 (1): 17–40. Bibcode:2007JRP....27...17H. doi:10.1088/0952-4746/27/1/001. PMID 17341802. The conclusion is reached that 0.1–0.3 GBq or more absorbed to blood of an adult male is likely to be fatal within 1 month. This corresponds to ingestion of 1–3 GBq or more, assuming 10% absorption to blood

[76] Health Risks of Radon and Other Internally Deposited Alpha-Emitters: BEIR IV. National Academy Press. 1988. p. 5. ISBN 0-309-03789-1.

[77] Health Effects Of Exposure To Indoor Radon. Washington: National Academy Press. 1999. Archived from the original on 2006-09-19.

[78] "The Straight Dope: Does smoking organically grown tobacco lower the chance of lung cancer?". Retrieved 2009-05-05.

[79] "Nuclear Regulatory Commission limits for ²¹⁰Po". U.S. NRC. 2008-12-12. Retrieved 2009-01-12.

[80] "PilgrimWatch – Pilgrim Nuclear – Health Impact". Retrieved 2009-05-05.

[Zimmerman-81] Zimmerman, Peter D. (2006-12-19). "The Smoky Bomb Threat". The New York Times. Retrieved 2006-12-19.

[82] Bagnall, p. 204

[83] Geoghegan, Tom (2006-11-24). "The mystery of Litvinenko's death". BBC News.

[bbc-84] "UK requests Lugovoi extradition". BBC News. 2007-05-28. Retrieved 2009-05-05.

[85] Watson, Roland (2006-12-03). "Focus: Cracking the code of the nuclear assassin". The Sunday Times (London). Archived from the original on 2008-02-10. Retrieved 2010-05-22.

[86] "American nuclear guinea pigs : three decades of radiation experiments on U.S. citizens". Retrieved 2015-06-09.

[87] Manier, Jeremy (2006-12-04). "Innocent chemical a killer". The Daily Telegraph (Australia). Retrieved 2009-05-05.

[88] Karpin, Michael (2006). The bomb in the basement: How Israel went nuclear and what that means for the world. Simon and Schuster. ISBN 0-7432-6594-7.

[LA_Times_2007-01-01-89] Maugh, Thomas; Karen Kaplan (2007-01-01). "A restless killer radiates intrigue". Los Angeles Times. Retrieved 2008-09-17.

[90] Bart, Katharina (2012-07-03). Swiss institute finds polonium in Arafat's effects. Reuters.

[91] "Experts exhume Arafat, seek evidence of poison". Reuters. 2012-11-27. Retrieved 2012-11-27.

[92] Froidevaux, P.; Baechler, S. B.; Bailat, C. J.; Castella, V.; Augsburger, M.; Michaud, K.; Mangin, P.; Bochud, F. O. O. (2013). "Improving forensic investigation for polonium poisoning". The Lancet 382 (9900): 1308. doi:10.1016/S0140-6736(13)61834-6. edit

[autogenerated1-93] Isachenkov, Vadim (2013-12-27) Russia: Arafat's death not caused by radiation. Associated Press.

[94] "Guidance for Industry. Internal Radioactive Contamination — Development of Decorporation Agents" (PDF). US Food and Drug Administration. Retrieved 2009-07-07.

[95] Rencováa J.; Svoboda V.; Holuša R.; Volf V. et al. (1997). "Reduction of subacute lethal radiotoxicity of polonium-210 in rats by chelating agents". International Journal of Radiation Biology 72 (3): 247. doi:10.1080/095530097143338.

[96] Baselt, R. Disposition of Toxic Drugs and Chemicals in Man, 10th edition, Biomedical Publications, Seal Beach, CA.

[97] "Swiss study: Polonium found in Arafat’s bones". Al Jazeera. 2013-11-06. Archived from the original on 2013-11-06.

[BoiceCohen2014-98] Boice, John D.; Cohen, Sarah S. et al. (2014). "Mortality Among Mound Workers Exposed to Polonium-210 and Other Sources of Radiation, 1944–1979". Radiation Research 181 (2): 140214120928006. doi:10.1667/RR13395.1. ISSN 0033-7587.

[99] "Staticmaster Ionizing Brushes". AMSTAT Industries. Retrieved 2009-05-05.

[100] "General domestic licenses for byproduct material". Retrieved 2009-05-05.

[101] Singleton, Don (2006-11-28). "The Availability of polonium-210". Retrieved 2006-11-29.

[102] "Radioactive Isotopes". United Nuclear. Retrieved 2007-03-19.

[103] Hill, C. R. (1960). "Lead-210 and Polonium-210 in Grass". Nature 187 (4733): 211–212. Bibcode:1960Natur.187..211H. doi:10.1038/187211a0.

[104] Hill, C.R. (1963). "Natural occurrence of unsupported radium-F (Po-210) in tissue". Health Physics (9): 952–953.

[105] Heyraud, M.; Cherry, R. D. (1979). "Polonium-210 and lead-210 in marine food chains". Marine Biology 52 (3): 227–236. doi:10.1007/BF00398136.

[106] Lacassagne, A. & Lattes, J. (1924) Bulletin d'Histologie Appliquée à la Physiologie et à la Pathologie, 1, 279.

[107] Vasken Aposhian, H.; Bruce, D. C. (1991). "Binding of Polonium-210 to Liver Metallothionein". Radiation Research 126 (3): 379–382. doi:10.2307/3577929. JSTOR 3577929. PMID 2034794.

[108] Hill, CR (1965). "Polonium-210 in man". Nature 208 (5009): 423–8. Bibcode:1965Natur.208..423H. doi:10.1038/208423a0. PMID 5867584.

[109] Hill, C. R. (1966). "Polonium-210 Content of Human Tissues in Relation to Dietary Habit". Science 152 (3726): 1261–2. Bibcode:1966Sci...152.1261H. doi:10.1126/science.152.3726.1261. PMID 5949242.

[Martell1974-110] Martell, E. A. (1974). "Radioactivity of tobacco trichomes and insoluble cigarette smoke particles". Nature 249 (5454): 214–217. Bibcode:1974Natur.249..215M. doi:10.1038/249215a0. Retrieved 20 July 2014.

[Martell1975-111] Martell, E. A. (1975). "Tobacco Radioactivity and Cancer in Smokers: Alpha interactions with chromosomes of cells surrounding insoluble radioactive smoke particles may cause cancer and contribute to early atherosclerosis development in cigarette smokers". American Scientist 63 (4): 404–412. Bibcode:1975AmSci..63..404M. JSTOR 27845575. PMID 1137236.

[112] Journal of the Royal Society of Medicine, The big idea: polonium, radon and cigarettes, Tidd J R Soc Med.2008; 101: 156–157 [1]

[113] The Age Melbourne Australia, Big Tobacco covered up radiation danger, William Birnbauer [2]

[114] Radford EP Jr; Hunt VR (1964). "Polonium 210: a volatile radioelement in cigarettes". Science 143 (3603): 247–9. Bibcode:1964Sci...143..247R. doi:10.1126/science.143.3603.247. PMID 14078362.

[115] Kelley TF (1965). "Polonium 210 content of mainstream cigarette smoke". Science 149 (3683): 537–538. Bibcode:1965Sci...149..537K. doi:10.1126/science.149.3683.537.

[116] Ota, Tomoko; Sanada, Tetsuya; Kashiwara, Yoko; Morimoto, Takao et al. (2009). "Evaluation for Committed Effective Dose Due to Dietary Foods by the Intake for Japanese Adults". Japanese Journal of Health Physics 44: 80–88. doi:10.5453/jhps.44.80.

[117] Smith-Briggs, JL; Bradley, EJ (1984). "Measurement of natural radionuclides in U.K. diet". Science of the Total Environment 35 (3): 431–40. doi:10.1016/0048-9697(84)90015-9. PMID 6729447.

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