background radiation - wikipedia, the free encyclopedia

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The weather station outsideof the AtomicTesting

Museum on a hot summer day.Displayed

background gamma radiation level is 9.8 µR/h

(0.82 mSv/a) This isvery close to the worldaverage

background radiation of 0.87 mSv/a from cosmic and

terrestrial sources.

Displaysshowing ambient radiation fields of

0.120-0.130 µSv/h (1.05-1.14 mSv/a) in a nuclear

power plant.This reading includes natural

background from cosmic and terrestrialsources, but

excludes any contribution from contamination in the

air,food, and water.

Average annualdosage from natural radiation varies

byseveral mSv between different European

countries.[4]

ackground radiationm Wikipedia, the free encyclopedia

ckground radiation is the ubiquitous ionizing radiation that the general population is exposed to, including natural and

ficial sources.

th natural and artificial background radiation varies by location.

Average annual human exposure to ionizing radiation (millisievert)

Radiation sourceWorld

[1]

USA[2]

Japan[3] Remark

Inhalation of air 1.26 2.28 0.40 mainly from radon, depends on indoor accumulation

Ingestion of food & water 0.29 0.28 0.40 (K-40, C-14, etc.)

Terrestrial radiation from

ground0.48 0.21 0.40 depends on soil and building material

osmic radiation from space 0.39 0.33 0.30 depends on altitude

sub total (natural) 2.40 3.10 1.50 sizeable population groups receive 10-20 mSv

Medical 0.60 3.00 2.30world-wide figure excludes radiotherapy;

US figure is mostly CT scans and nuclear medicine.

Consumer items - 0.13 cigarettes, air travel, building materials, etc.

Atmospheric nuclear testing 0.005 - 0.01 peak of 0.11 mSv in 1963 and declining since; higher near sites

Occupational exposure 0.005 0.005 0.01

world-wide average to all workers is 0.7 mSv, mostly due to radon in

mines;[1]

US is mostly due to medicaland aviation workers.[2]

Chernobyl accident 0.002 - 0.01 peak of 0.04 mSv in 1986 and declining since; higher near site

Nuclear fuel cycle 0.0002 0.001 up to 0.02 mSv near sites; excludes occupational exposure

Other - 0.003 Industrial, security, medical, educational, and research

sub total (artificial) 0.61 3.14 2.33

Total 3.01 6.24 3.83 millisievert per year

Contents

1 Natural background radiation

1.1 Air

1.2 Cosmic radiation

1.3 Terrestrial sources

1.4 Food and water

1.5 Areas with high NBR

1.6 Photoelectric

2 Artificial background radiation

2.1 Medical

2.2 Consumer items

2.3 Atmospheric nuclear testing

2.4 Occupational exposure

2.5 Nuclear accidents

2.6 Nuclear fuel cycle

2.7 Other

3 Other usage

4 See also

5 References

6 External links

atural background radiation

dioactivematerial is found throughout nature. Detectable amounts occurs naturally in the soil, rocks, water, air, and

etation, from which it is inhaled and ingested into the body. In addition to this internal exposure, humans also receive

ernal exposure from radioactive materials that remain outside the body and from cosmic radiation from space. The

rldwide average natural dose to humans is about 2.4 millisievert (mSv) per year.[1] This is four times more than the

rldwide average artificial radiation exposure, which in the year 2008 amounted to about 0.6 mSv per year. In some rich

ntries like the US and Japan , artificial exposure is, on average, greater than the natural exposure, due to greater access

medical imaging. In Europe, average natural background exposure by country ranges from under 2 mSv annually in the

ited Kingdom to more than 7 mSv annually in Finland.[4]

r

e biggest source of natural background radiation is airborne radon, a radioactive gas that emanates from the ground.

don and its isotopes, parent radionuclides, and decay products all contribute to an average inhaled dose of 1.26 mSv/a.

don is unevenly distributed and variable with weather, such that much higher doses apply to many areas of the world,

ere it represents a significant health hazard. Concentrations over 500 times higher than the world average have been

nd inside buildings in Scandinavia, the United States, Iran, and the Czech Republic.[5] Radon is a decay product of uranium, which is relatively common in the Earth's

st, but more concentrated in ore-bearing rocks scattered around the world. Radon seeps out of these ores into the atmosphere or into ground water or infiltrates into

ldings. It can be inhaled into the lungs, along with its decay products, where they will reside for a period of time after exposure.



Estimate of the maximum dose of

radiation received at an altitude of 12

km January 20, 2005,following a

violent solar flare. The doses are

expressed in microsieverts per hour.

hough radon is naturally occurring, exposure can be enhanced or diminished by human activity, notably house construction. A poorly sealed basement in an otherwise well

ulated house can result in the accumulation of radon within the dwelling, exposing its residents to high concentrations. The widespread construction of well insulated and

led homes in the northern industrialized world has led to radon becoming the primary source of background radiation in some localities in northern North America and

rope.[citation needed ] Since it is heavier than air, radon tends to collect in basements and mines. Basement sealing and suction ventilation reduce exposure. Some building

terials, for example lightweight concrete with alum shale, phosphogypsum and Italian tuff, may emanate radon if they contain radium and are porous to gas.[5]

diation exposure from radon is indirect. Radon has a short half-life (4 days) and decays into other solid particulate radium-series radioactive nuclides. These radioactive

ticles are inhaled and remain lodged in the lungs, causing continued exposure. Radon is thus the second leading cause of lung cancer after smoking, and accounts for 15,000

22,000 cancer deaths per year in the US alone.[6]

out 100,000 Bq/m3 of radon was found in Stanley Watras's basement in 1984.[7][8] He and his neighbours in Boyertown, Pennsylvania, United States may hold the record

the most radioactive dwellings in the world. International radiation protection organizations estimate that a committed dose may be calculated by multiplying the

ilibrium equivalent concentration (EEC) of radon by a factor of 8 to 9nSv·m

3

Bq·h and the EEC of thoron by a factor of 40nSv·m

3

Bq·h .[1]

osmic radiation

Main article: Cosmic ray

e Earth, and all living things on it, are constantly bombarded by radiation from outer space. This radiation primarily consists of

itively charged ions from protons to iron and larger nuclei derived sources outside our solar system. This radiation interacts with

ms in the atmosphere to create an air shower of secondary radiation, including X-rays, muons, protons, alpha particles, pions,

ctrons, and neutrons. The immediate dose from cosmic radiation is largely from muons, neutrons, and electrons, and this dose varies

different parts of the world based largely on the geomagnetic field and altitude. This radiation is much more intense in the upper

posphere, around 10 km altitude, and is thus of particular concern for airline crews and frequent passengers, who spend many hours

year in this environment. During their flights airline crews typically get an extra dose on the order of 2.2 mSv (220 mrem) per year.

milarly, cosmic rays cause higher background exposure in astronauts than in humans on the surface of Earth. Astronauts in low

its, such as in the International Space Station or the Space Shuttle, are partially shielded by the magnetic field of the Earth, but alsofer from the Van Allen radiation belt which accumulates cosmic rays and results from the earths magnetic field. Outside low Earth

it, as experienced by the Apollo astronauts who traveled to the Moon, this background radiation is much more intense, and

resents a considerable obstacle to potential future long term human exploration of the moon or Mars.

smic rays also cause elemental transmutation in the atmosphere, in which secondary radiation generated by the cosmic rays

mbines with atomic nuclei in the atmosphere to generate different nuclides. Many so-called cosmogenic nuclides can be produced, but probably the most notable is

bon-14, which is produced by interactions with nitrogen atoms. These cosmogenic nuclides eventually reach the Earth's surface and can be incorporated into living

anisms. The production of these nuclides varies slightly with short-term variations in solar cosmic ray flux, but is considered practically constant over long scales of

usands to millions of years. The constant production, incorporation into organisms and relatively short half-life of carbon-14 are the principles used in radiocarbon dating of

ient biological materials such as wooden artifacts or human remains.

rrestrial sources

rrestrial radiation, for the purpose of the table above, only includes sources that remain external to the body. The major radionuclides of concern are potassium, uranium

d thorium and their decay products, some of which, like radium and radon are intensely radioactive but occur in low concentrations. Most of these sources have beenreasing, due to radioactive decay since the formation of the Earth, because there is no significant amount currently transported to the Earth. Thus, the present activity on

th from uranium-238 is only half as much as it originally was because of its 4.5 billion year half-life, and potassium-40 (half-life 1.25 billion years) is only at about 8% of

ginal activity. The effects on humans of the actual diminishment (due to decay) of these isotopes is minimal however. This is because humans evolved too recently for the

ference in activity over a fraction of a half-life to be significant. Put another way, human history is so short in comparison to a half-life of a billion years, that the activity of

se long-lived isotopes has been effectively constant throughout our time on this planet.

addition, many shorter half-life and thus more intensely radioactive isotopes have not decayed out of the terrestrial environment, however, because of natural on-going

duction of them. Examples of these are radium-226 (decay product of uranium-238) and radon-222 (a decay product of radium-226).

od and water

me of the essential elements that make up the human body, mainly potassium and carbon, have radioactive isotopes that add significantly to our background radiation dose.

average human contains about 30 milligrams of potassium-40 (40K) and about 10 nanograms (10−8 g) of carbon-14 (14C), which has a decay half-life of 5,730 years.

cluding internal contamination by external radioactive material, the largest component of internal radiation exposure from biologically functional components of the human

dy is from potassium-40. The decay of about 4,000 nuclei of 40K per second[10] makes potassium the largest source of radiation in terms of number of decaying atoms. The

rgy of beta particles produced by 40K is also about 10 times more powerful than the beta particles from 14C decay. 14C is present in the human body at a level of 3700 Bq

h a biological half-life of 40 days.[11] There are about 1,200 beta particles per second produced by the decay of 14C. However, a 14C atom is in the genetic information of

ut half the cells, while potassium is not a component of DNA. The decay of a 14C atom inside DNA in one person happens about 50 times per second, changing a carbon

m to one of nitrogen.[12] The global average internal dose from radionuclides other than radon and its decay products is 0.29 mSv/a, of which 0.17 mSv/a comes from 40K,

2 mSv/a comes from the uranium and thorium series, and 12 µSv/a comes from 14C.[1]

eas with high NBR

me areas have greater dosage than the country-wide averages.[13] In the world in general, exceptionally high natural background locales include Ramsar in Iran, Guarapari in

zil, Karunagappalli in India,[14] Arkaroola, South Australia [15] and Yangjiang in China.[16]

e highest level of purely natural radiation ever recorded on the Earth's surface was 90 µGy/h on a Brazilian black beach (areia preta in Portuguese) composed of monazite.

This rate would convert to 0.8 Gy/a for year-round continuous exposure, but in fact the levels vary seasonally and are much lower in the nearest residences. The recordasurement has not been duplicated and is omitted from UNSCEAR's latest reports. Nearby tourist beaches in Guarapari and Cumuruxatiba were later evaluated at 14 and

µGy/h.[18][19]



Per capita thyroid doses in the

continental United States resulting

from all exposureroutes from all

atmospheric nuclear tests conducted at

the Nevada Test Site from 1951-1962.

e highest background radiation in an inhabited area is found in Ramsar, primarily due to the use of local naturally radioactive limestone as a building material. The 1000

st exposed residents receive an average external effective radiation dose of 6 mSv per year, (0.6 rem/yr,) six times more than the ICRP recommended limit for exposure to

public from artificial sources.[20] They additionally receive a substantial internal dose from radon. Record radiation levels were found in a house where the effective dose

e to ambient radiation fields was 131 mSv/a, (13.1 rem/yr) and the internal committed dose from radon was 72 mSv/a (7.2 rem/yr).[20] This unique case is over 80 times

her than the world average natural human exposure to radiation.

demiological studies are underway to identify health effects associated with the high radiation levels in Ramsar. It is much too early to draw statistically significant

nclusions,[20] but so far radiation hormesis has not been observed, and data from Ramsar does not provide justification to relax existing regulatory dose limits.[21]

otoelectric

ckground radiation doses in the immediate vicinities of particles of high atomic number materials, within the human body, have a small enhancement due to the photoelectric

ect.[22]

rtificial background radiation

edical

e global average human exposure to artificial radiation is 0.6 mSv/a, primarily from medical imaging. This medical component can range much higher, with an average of

mSv per year across the USA population.[2] Other human contributors include smoking, air travel, radioactive building materials, historical nuclear weapons testing, nuclear

wer accidents and nuclear industry operation.

ypical chest x-ray delivers 0.02 mSv (2 mrem) of effective dose.[23] A dental x-ray delivers a dose of 5 to 10 µSv[24] The average American receives about 3 mSv of

gnostic medical dose per year; countries with the lowest levels of health care receive almost none. Radiation treatment for various diseases also accounts for some dose, both

ndividuals and in those around them.

nsumer items

garettes contain polonium-210, originating from the decay products of radon, which stick to tobacco leaves. Heavy smoking results in a radiation dose of 160 mSv/year to

alized spots at the bifurcations of segmental bronchi in the lungs from the decay of polonium-210. This dose is not readily comparable to the radiation protection limits,

ce the latter deal with whole body doses, while the dose from smoking is delivered to a very small portion of the body.[25]

travel causes increased exposure to cosmic radiation. The average extra dose to flight personnel is 2.19 mSv/year.[26]

mospheric nuclear testing

quent above-ground nuclear explosions between the 1940s and 1960s scattered a substantial amount of radioactive contamination.

me of this contamination is local, rendering the immediate surroundings highly radioactive, while some of it is carried longer

tances as nuclear fallout; some of this material is dispersed worldwide. The increase in background radiation due to these tests

ked in 1963 at about 0.15 mSv per year worldwide, or about 7% of average background dose from all sources. The Limited Test

n Treaty of 1963 prohibited above-ground tests, thus by the year 2000 the worldwide dose from these tests has decreased to only

05 mSv per year.[27]

ccupational exposure

e ICRP recommends limiting occupational radiation exposure to 50 mSv (5 rem) per year, and 100 mSv (10 rem) in 5 years.[28]

an IAEA conference in 2002, it was recommended that occupational doses below 1–2 mSv per year do not warrant regulatory

utiny.[29]

uclear accidents

der normal circumstances, nuclear reactors release small amounts of radioactive gases, which cause negligibly small radiation exposures to the public. Events classified on

International Nuclear Event Scale as incidents typically do not release any additional radioactive substances into the environment. Large releases of radioactivity from

lear reactors are extremely rare. Until the present day, there were two major civilian accidents - the Chernobyl accident and the Fukushima I nuclear accidents - which

sed substantial contamination. The Chernobyl accident was the only one to cause immediate deaths.

al doses from the Chernobyl accident ranged from 10 to 50 mSv over 20 years for the inhabitants of the affected areas, with most of the dose received in the first years after

disaster, and over 100 mSv for liquidators. There were 28 deaths from acute radiation syndrome.[30]

al doses from the Fukushima I accidents were between 1 and 15 mSv for the inhabitants of the affected areas. Thyroid doses for children were below 50 mSv. 167 cleanup

rkers received doses above 100 mSv, with 6 of them receiving more than 250 mSv (the Japanese exposure limit for emergency response workers).[31]

e average dose from the Three Mile Island accident was 0.01 mSv.[32]

n-civilian: In addition to the civilian accidents described above, several accidents at early nuclear weapons facilities - such as the Windscale fire, the contamination of the

cha River by the nuclear waste from the Mayak compound, and the Kyshtym disaster at the same compound - released substantial radioactivity into the environment. The

ndscale fire resulted in thyroid doses of 5-20 mSv for adults and 10-60 mSv for children.[33] The doses from the accidents at Mayak are unknown.

uclear fuel cycle

e Nuclear Regulatory Commission, the United States Environmental Protection Agency, and other U.S. and international agencies, require that licensees limit radiation

osure to individual members of the public to 1 mSv (100 mrem) per year.

her

al plants emit radiation in the form of radioactive fly ash which is inhaled and ingested by neighbours, and incorporated into crops. A 1978 paper from Oak Ridge National

boratory estimated that coal-fired power plants of that time may contribute a whole-body committed dose of 19 µSv/a to their immediate neighbours in a radius of 500 m.[34]

e United Nations Scientific Committee on the Effects of Atomic Radiation's 1988 report estimated the committed dose 1 km away to be 20 µSv/a for older plants or 1 µSv/a



newer plants with improved fly ash capture, but was unable to confirm these numbers by test.[35] When coal is burned, uranium, thorium and all the uranium daughters

umulated by disintegration — radium, radon, polonium — are released.[36] Radioactive materials previously buried underground in coal deposits are released as fly ash or,

y ash is captured, may be incorporated into concrete manufactured with fly ash.

ther usage

other contexts, background radiation may simply be any radiation that is pervasive, whether ionizing or not. A particular example of this is the cosmic microwave

kground radiation, a nearly uniform glow that fills the sky in the microwave part of the spectrum; stars, galaxies and other objects of interest in radio astronomy stand out

inst this background.

a laboratory, background radiation refers to the measured value from any sources that affect an instrument when a radiation source sample is not being measured. This

kground rate, which must be established as a stable value by multiple measurements, usually before and after sample measurement, is subtracted from the rate measured

en the sample is being measured.

ckground radiation for occupational doses measured for workers is all radiation dose that is not measured by radiation dose measurement instruments in potential

upational exposure conditions. This includes both "natural background radiation" and any medical radiation doses. This value is not typically measured or known from

veys, such that variations in the total dose to individual workers is not known. This can be a significant confounding factor in assessing radiation exposure effects in a

pulation of workers who may have significantly different natural background and medical radiation doses. This is most significant when the occupational doses are very

w.

ee also

Background radiation equivalent time (BRET)

Environmental radioactivity

Banana equivalent dose

eferences

1. ^ a b c d e United NationsScientific Committee on the Effects of Atomic Radiation (2008

(published 2010)). Sources and effects of ionizing radiation (http://www.unscear.org/

unscear/en/publications/2008_1.html). New York:United Nations.p. 4.ISBN 978-92-1-142274-0. Retrieved 9 November 2012.

2. â b c

Ionizing radiation exposure of the population of the United States (http://

www.ncrppublications.org/Reports/160).Bethesda,Md.: National Councilon RadiationProtectionand Measurements. 2009. ISBN 978-0-929600-98-7.NCRP No. 160.

3. ^ Ministry of Education,Culture,Sports,Science,and Technology of Japan "Radiation inenvironment" (http://www.kankyo-hoshano.go.jp/04/04-1.html) retrieved2011-6-29

4. ^ a b "Natural RadiationAtlas of Europe"(http://funk.on.br/esantos/doutorado/ARTIGOS%

20AEROGAMA/papers%20sem%20catalogar/491.pdf).National Radiological Protection

Board (U.K.) for the Commission of the European Communities (1992).

5. â b

>United NationsScientific Committee on the Effects of Atomic Radiation(2006

(published 2008)). "Annex E:Sources-to-effects assessment for radon in homes and

workplaces" (http://www.unscear.org/docs/reports/2006/09-81160_Report_Annex_E_

2006_Web.pdf). Effects of Ionizing Radiation II. NewYork:United Nations.

ISBN 978-92-1-142263-4.Retrieved 2 December 2012.6. ^ Radon and Cancer: Questions andAnswers - National Cancer Institute (USA) (http://

www.cancer.gov/cancertopics/factsheet/Risk/radon)

7. ^ Thomas, John J.; Thomas, Barbara R.; Overeynder, Helen M. (September 27–30,1995).

"Indoor Radon Concentration Data: Its Geographic and Geologic Distribution, an Examplefrom the Capital District,NY"(http://wpb-radon.com/Radon_research_papers/1995%

20Nashville,%20TN/1995_14_Indoor%20Radon%20Concentration%20Data--Geographic

%20and%20Geologic%20Distribution,%20Captial%20District,%20NY.pdf). InternationalRadon Symposium (http://internationalradonsymposium.org/). Nashville, TN: American

Association of Radon Scientists and Technologists.http://wpb-radon.com/Radon_research_

papers/1995%20Nashville,%20TN/1995_14_Indoor%20Radon%20Concentration%20Data--Geographic%20and%20Geologic%20Distribution,%20Captial%20District,%

20NY.pdf.Retrieved 2012-11-28.

8. ^ Upfal, Mark J.; Johnson, Christine (2003). "65 Residential Radon" (http://toxicology.ws/

Greenberg/Chapter%2065%20-%20Residential%20Radon.pdf). In Greenberg,Michael I.;

Hamilton, RichardJ.; Phillips, Scott D. et al. Occupational, industrial, and environmental

toxicology (2nd ed.). St Louis,Missouri:Mosby.ISBN 9780323013406. Retrieved 28

November 2012.9. ^ "Radiation Exposure During Commercial AirlineFlights" (http://www.hps.org/

publicinformation/ate/faqs/commercialflights.html). Retrieved 2011-03-17.

0. ^ Radioactive human body — Harvard University Natural Science Lecture Demonstrations

(http://www.fas.harvard.edu/~scdiroff/lds/QuantumRelativity/RadioactiveHumanBody/

RadioactiveHumanBody.html)

1. ^ http://www.ead.anl.gov/pub/doc/carbon14.pdf

2. ^ Asimov,Isaac (1976) [1957]. "The Explosions Within Us". Only A Trillion (Revised and

updated ed.). New York:ACE books.pp. 37–39. ISBN 1-157-09468-6.

3. ^ Annual terrestrialradiation doses in the world (http://www.taishitsu.or.jp/radiation/index-

e.html)

4. ^ Nair, MK; Nambi, KS; Amma, NS; Gangadharan,P; Jayalekshmi, P; Jayadevan, S;

Cherian,V; Reghuram,KN (1999). "Population study in the high natural background

radiation area in Kerala, India". Radiation research 152 (6 Suppl): S145–8.

doi:10.2307/3580134 (http://dx.doi.org/10.2307%2F3580134). PMID 10564957 (// www.ncbi.nlm.nih.gov/pubmed/10564957).

5. ^ Extreme Slime (http://www.abc.net.au/catalyst/stories/s692473.htm)

6. ^ Zhang,SP. Mechanism study of ada ptive response in high background radiation area of

Yangjiang in China (http://europepmc.org/abstract/MED/21092626/

reload=0;jsessionid=GMiewFcfxTMnb7wOgVYB.6). Europe PubMed Central.Retrieved 8

December2012.

7. ^ United Nations Scientific Committee on the Effects of AtomicRadiation (2000)."Annex

B"(http://www.unscear.org/unscear/publications/2000_1.html). Sources and Effects of

Ionizing Radiation. vol.1. United Nations.p. 121. Retrieved 11 November 2012.

8. ^ Freitas, AC; Alencar,AS (2004). "Gamma dose rates and distribution of naturalradionuclides in sand beaches--Ilha Grande,Southeastern Brazil" (http://www.sr2.uerj.br/

ceads/artigos_e_livros/Freitas_Antonio-2004-2.pdf). Journal of environmental

radioactivity 75 (2): 211–23. doi:10.1016/j.jenvrad.2004.01.002 (http://

dx.doi.org/10.1016%2Fj.jenvrad.2004.01.002). ISSN 0265-931X (//www.worldcat.org/ issn/0265-931X). PMID 15172728 (//www.ncbi.nlm.nih.gov/pubmed/15172728).

Retrieved 2 December 2012.

19. ^ Vasconcelos, Danilo C.et al (September27 to October 2,2009). "Natural Radioactivity in

Extreme South ofBahia,Brazil UsingGamma-Ray Spectrometry"(http://library.sinap.ac.cn/ db/hedianwencui201103/%E5%85%A8%E6%96%87/41109077.pdf). International

Nuclear Atlantic Conference (http://www.inac2011.com.br/). Rio de Janeiro:Associação

Brasileira de Energia Nuclear. ISBN 978-85-99141-03-8.http://library.sinap.ac.cn/db/ hedianwencui201103/%E5%85%A8%E6%96%87/41109077.pdf. Retrieved 2 December

2012.

20. â b c

Hendry,Jolyon H; Simon,Steven L; Wojcik,Andrzej; Sohrabi, Mehdi; Burkart,

Werner; Cardis, Elisabeth; Laurier,Dominique; Tirmarche, Margot; Hayata, Isamu (1 June2009). "Human exposure to high natural background radiation: what can it teachus about

radiation risks?"(http://cricket.biol.sc.edu/papers/natural/Hendry%20et%20al%

202009.pdf). Journal of Radiological Protection 29 (2A): A29–A42.

doi:10.1088/0952-4746/29/2A/S03 (http://dx.doi.org/10.1088%2F0952-4746%2F29%

2F2A%2FS03). PMID 19454802 (//www.ncbi.nlm.nih.gov/pubmed/19454802). Retrieved

1 December2012.21. ^ Ghiassi-nejad,M; Mortazavi,SM; Cameron, JR; Niroomand-rad,A; Karam, PA (2002

Jan). "Veryhigh background radiation areas of Ramsar, Iran:preliminary biological

studies" (http://www.probeinternational.org/Ramsar.pdf). Health physics 82 (1):87–93 [92]. PMID 11769138 (//www.ncbi.nlm.nih.gov/pubmed/11769138). Retrieved 11 November

2012."we do not claim to have seen hormetic effects in any of thosestudied. ... the available

data do not seem sufficient to cause national orinternational advisorybodies to change theircurrent conservative radiation protection recommendations;"

22. ^ Pattison,J. E.; Hugtenburg,R. P.; Green, S. (2009)."Enhancement of natural backgroundgamma-radiation dose around uranium microparticles in the human body". Journal of the

Royal Society Interface 7 (45): 603–11. doi:10.1098/rsif.2009.0300 (http:// dx.doi.org/10.1098%2Frsif.2009.0300).

23. ^ Wall,B.F.; and Hart,D. (1997). "Revised Radiation Doses for Typical X-Ray

Examinations"(http://bjr.birjournals.org/content/70/833/437.full.pdf). The British Journal

of Radiology 70 (833): 437–439. PMID 9227222 (//www.ncbi.nlm.nih.gov/

pubmed/9227222). Retrieved 18 May 2012. (5,000 patient dose measurements from 375

hospitals)

24. ^ Hart, D.; and Wall,B.F. (2002). Radiation Exposure of the UK Population from Medicaland Dental X-ray Examinations (http://medicalphysicist.co.uk/nrpb_w4.pdf). NationalRadiological Protection Board.p. 9. ISBN 0859514684. Retrieved 18 May 2012.

25. ^ Dade W. Moeller."Doses from cigarette smoking"(http://hps.org/publicinformation/ate/ q3137.html). Health Physics Society. Retrieved 2013-01-24.

26. ^ Health Physics Society."Radiation exposure during commercial airline flights"(http:// www.hps.org/publicinformation/ate/faqs/commercialflights.html). Retrieved 2013-01-24.

27. ^ United Nations ScientificCommittee on the Effects of AtomicRadiation (http:// www.unscear.org/unscear/en/publications.html)

28. ^ "The 2007 Recommendations of the International Commission on Radiological

Protection" (http://www.icrp.org/publication.asp?id=ICRP%20Publication%20103).

Annals of the ICRP. ICRP publication 103 37 (2–4). 2007. ISBN 978-0-7020-3048-2.

Retrieved 17 May 2012.

29. ^ http://www-pub.iaea.org/MTCD/publications/PDF/Pub1145_web.pdf

30. ^ World Health Organization (2006-04). "Health effects of the Chernobyl accident: anoverview" (http://www.who.int/ionizing_radiation/chernobyl/backgrounder/en/index.html).

Retrieved 2013-01-24.

31. ^ Geoff Brumfiel (2012-05-23). "Fukushima’s doses tallied"(http://www.nature.com/news/

fukushima-s-doses-tallied-1.10686). Nature.Retrieved 2013-01-24.

32. ^ U.S.Nuclear RegulatoryCommission (2009-08). "Backgrounder on the Three Mile Island

Accident" (http://www.nrc.gov/reading-rm/doc-collections/fact-sheets/3mile-isle.html).

Retrieved 2013-01-24.

33. ^ "Radiological Consequences of the 1957 Windscale Fire"(http://karws.gso.uri.edu/Marsh/ Newsgroups/Wscal-is.htm). 1997-10-10. Retrieved 2013-01-24.

34. ^ McBride, J.P.; Moore, R.E.; Witherspoon, J.P.; Blanco, R.E. (1978 Dec 8). "Radiologicalimpact of airborne effluents of coal and nuclear plants" (http://www.ornl.gov/info/

reports/1977/3445605115087.pdf). Science 202 (4372):1045–50.Bibcode:1978Sci...202.1045M(http://adsabs.harvard.edu/abs/1978Sci...202.1045M).



doi:10.1126/science.202.4372.1045 (http://dx.doi.org/10.1126%2Fscience.202.4372.1045).

PMID 17777943 (//www.ncbi.nlm.nih.gov/pubmed/17777943). Retrieved 15 November

2012.

5. ^ United Nations Scientific Committee on the Effects of AtomicRadiation (1988)."Annex

A" (http://www.unscear.org/unscear/en/publications/1988.html). Sources, Effects and Risks

of Ionizing Radiation. New York:United Nations.p. 83. ISBN 92-1-142143-8. Retrieved 16

November 2012.

36. ^ Gabbard,Alex (1993). "CoalCombustion: Nuclear Resource or Danger?"(http://

www.ornl.gov/info/ornlreview/rev26-34/text/colmain.html). Oak Ridge National

Laboratory Review 26 (3–4):18–9.

xternal links

Background radiation description (http://www.rerf.or.jp/glossary_e/backgrou.htm) from the Radiation Effects Research Foundation (http://www.rerf.or.jp/index_e.html)

Environmental and Background Radiation FAQ (http://www.hps.org/publicinformation/ate/cat10.html) from the Health Physics Society (http://hps.org/)

Radiation Dose Chart (http://www.ans.org/pi/resources/dosechart/) from the American Nuclear Society (http://www.ans.org/)

Radiation Dose Calculator (http://www.epa.gov/radiation/understand/calculate.html) from the US Environmental Protection Agency (http://www.epa.gov/)

rieved from "http://en.wikipedia.org/w/index.php?title=Background_radiation&oldid=549004550"

egories: Radioactivity Cosmic rays Background radiation

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