{"id":1682,"date":"2017-10-03T04:00:52","date_gmt":"2017-10-03T04:00:52","guid":{"rendered":"https:\/\/himinn.fjarver.is\/mengunsjavar\/?p=1682"},"modified":"2024-10-21T22:24:56","modified_gmt":"2024-10-21T22:24:56","slug":"6-4-liffraedileg-ahrif-geislunar","status":"publish","type":"post","link":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/2017\/10\/03\/6-4-liffraedileg-ahrif-geislunar\/","title":{"rendered":"6.4 L\u00edffr\u00e6\u00f0ileg \u00e1hrif geislunar"},"content":{"rendered":"

Geislavirk efni hafa veri\u00f0 hluti af n\u00e1tt\u00farulegu umhverfi \u00e1 j\u00f6r\u00f0inni fr\u00e1 upphafi. \u00deau senda fr\u00e1 s\u00e9r svokalla\u00f0a j\u00f3nandi geislun<\/em>, \u00fe.e. geislun sem hefur n\u00e6ga orku til a\u00f0 r\u00edfa rafeind fr\u00e1 frumeind, en sl\u00edkt getur m.a. ska\u00f0a\u00f0 erf\u00f0aefni frumna (DNA). Vi\u00f0 ver\u00f0um daglega fyrir litlu magni j\u00f3nandi geislunar, b\u00e6\u00f0i fr\u00e1 n\u00e1tt\u00farulegum og mannger\u00f0um uppsprettum. \u00cd kj\u00f6lfar kjarnorkutilrauna og kjarnorkuslysa eykst magn j\u00f3nandi geislunar \u00ed n\u00e6sta n\u00e1grenni og getur mengunin \u00ed umhverfinu vara\u00f0 \u00ed langan t\u00edma. E\u00f0li, alvarleiki og t\u00edmasetning m\u00f6gulegra einkenna fer eftir tegund geislunar, st\u00e6r\u00f0 geislaskammts og hra\u00f0a geislunarinnar (\u00fe.e. magni upptekinnar geislunar \u00e1 t\u00edmaeiningu). Einnig skiptir n\u00e6mni einstaklings m\u00e1li en n\u00e6mnin er m.a. h\u00e1\u00f0 aldri, kyni og heilsu vi\u00f0komandi. Heilsufarsleg \u00e1hrif geislamengunar r\u00e1\u00f0ast ekki eing\u00f6ngu af styrk og eitur\u00e1hrifum efnanna, heldur skiptir heg\u00f0un vi\u00f0komandi efnis \u00ed n\u00e1tt\u00farunni einnig miklu m\u00e1li, en h\u00fan r\u00e6\u00f0st af efnafr\u00e6\u00f0ilegum eiginleikum efnisins. Gr\u00f3\u00f0urfar, landnytjar og f\u00e6\u00f0uvenjur skipta einnig m\u00e1li.<\/p>\n

Geislavirk efni eru mun h\u00e6ttulegri ef \u00feau komast inn \u00ed l\u00edkamann. Pl\u00fat\u00f3n\u00edum er t.a.m. mj\u00f6g eitra\u00f0 en l\u00edkurnar \u00e1 \u00fev\u00ed a\u00f0 \u00fea\u00f0 komist \u00ed l\u00edkamann eru frekar litlar. Komist \u00fea\u00f0 hins vegar inn \u00ed l\u00edkamann er \u00fea\u00f0 st\u00f3rh\u00e6ttulegt.<\/p>\n

\u00c1\u00f0ur en lengra er haldi\u00f0 skulum vi\u00f0 fara yfir nokkrar skilgreiningar. Geislaskammtur<\/em><\/span> er m\u00e6likvar\u00f0i \u00e1 \u00fe\u00e1 orku sem vefur e\u00f0a l\u00edff\u00e6ri ver\u00f0ur fyrir vegna j\u00f3nandi geislunar. Geislaskammtur er m\u00e6ldur \u00ed j\u00falum \u00e1 hvert kg vefs (J\/kg) og kallast m\u00e6lieiningin Gy<\/span>. \u00de\u00f3tt geislaskammtur s\u00e9 mikilv\u00e6g st\u00e6r\u00f0 \u00ed e\u00f0lisfr\u00e6\u00f0inni tekur h\u00fan ekki tillit til \u00feess a\u00f0 \u00f3l\u00edkar tegundir geislunar valda mismiklum ska\u00f0a \u00ed l\u00edfverum. T.d. geta 0,05 Gy sem orsakast af alfa\u00f6gnum valdi\u00f0 jafnmiklum ska\u00f0a og 1 Gy af gammageislun. \u00deess vegna er hlutgeisla\u00e1lag<\/em><\/span>\u00a0einnig m\u00e6lt, en \u00fea\u00f0 tekur tillit til \u00feess a\u00f0 mismunandi form geislunar (\u03b1, \u03b2, \u03b3) veldur mismiklum l\u00edffr\u00e6\u00f0ilegum ska\u00f0a. Hlutgeisla\u00e1lag f\u00e6st me\u00f0 \u00fev\u00ed a\u00f0 margfalda geislaskammt hverrar tegundar geislunar me\u00f0 lei\u00f0r\u00e9ttingarstu\u00f0li (Q) til a\u00f0 endurspegla \u00feann ska\u00f0a sem vi\u00f0komandi tegund geislunar getur valdi\u00f0. Gildi Q er h\u00e1\u00f0 \u00fev\u00ed hversu mikilli j\u00f3nun geislun veldur. Alfa-\u00f6gn veldur geislun sem svarar til einnar millj\u00f3nar j\u00f3napara \u00e1 hvern millimetra af vi\u00f0mi\u00f0unarvef en beta-\u00f6gn og gammageislun um 10.000 \u00e1 hvern millimetra. Q hefur veri\u00f0 gefi\u00f0 gildi\u00f0 1 fyrir gammageislun og gildin fyrir a\u00f0rar tegundir geislunar eru mi\u00f0u\u00f0 vi\u00f0 hlutfallslegt gildi \u00feeirra mi\u00f0a\u00f0 vi\u00f0 gammageislun. Q fyrir beta- og gammageislun er \u00fev\u00ed 1, sem og gildi\u00f0 fyrir r\u00f6ntgengeisla og rafeindir. Gildi Q fyrir nifteindir er 5, en 20 fyrir h\u00e1hra\u00f0a-nifteindir, r\u00f3teindir og fyrir alfa-agnir.<\/p>\n

Hlutgeisla\u00e1lag (\u00fe.e. geislaskammtur margfalda\u00f0ur me\u00f0 lei\u00f0r\u00e9ttingarstu\u00f0linum Q) er m\u00e6lt \u00ed s\u00edvertum<\/span>, skammstafa\u00f0 Sv. Hlutgeisla\u00e1lagi\u00f0 segir \u00fe\u00f3 ekki alla s\u00f6gu, \u00fev\u00ed a\u00f0 einnig \u00fearf a\u00f0 taka tillit til \u00feess a\u00f0 sumir hlutar l\u00edkamans eru vi\u00f0kv\u00e6mari fyrir geislun en a\u00f0rir. Til d\u00e6mis er tilteki\u00f0 hlutgeisla\u00e1lag mun l\u00edklegra til a\u00f0 valda krabbameini \u00ed lungum en lifur, \u00fev\u00ed a\u00f0 lungun eru vi\u00f0kv\u00e6mari fyrir geislun. \u00c1hrif geislunar \u00e1 \u00e6xlunarf\u00e6ri eru s\u00e9rstakt \u00e1hyggjuefni vegna \u00e1h\u00e6ttunnar \u00e1 arfgengum \u00e1hrifum. \u00dev\u00ed er svokalla\u00f0 geisla\u00e1lag<\/em><\/span>\u00a0einnig meti\u00f0, en \u00fea\u00f0 segir til um \u00e1h\u00e6ttu einstaklings af j\u00f3nandi geislun. Geisla\u00e1lagi\u00f0 er vegi\u00f0 me\u00f0altal \u00e1hrifa hlutgeisla\u00e1lags \u00e1 l\u00edff\u00e6ri l\u00edkamans, \u00fear sem hvert l\u00edff\u00e6ri hefur v\u00e6gisstu\u00f0ul \u00ed samr\u00e6mi vi\u00f0 hlut \u00feess \u00ed heildar\u00e1h\u00e6ttu l\u00edkamans. Geisla\u00e1lagi\u00f0 er l\u00edka m\u00e6lt \u00ed s\u00edvertum og \u00fat fr\u00e1 \u00fev\u00ed m\u00e1 \u00e1\u00e6tla l\u00edkurnar \u00e1 krabbameinum og arfgengum \u00e1hrifum \u00ed kj\u00f6lfar l\u00edtilla geislaskammta. Geisla\u00e1lagi\u00f0 \u00e1 hins vegar ekki a\u00f0 vera m\u00e6likvar\u00f0i \u00e1 \u00e1hrif vegna h\u00e1rra geislaskammta.<\/p>\n

J\u00f3nandi geislun getur haft \u00e1hrif \u00e1 frumur l\u00edkamans og valdi\u00f0 frumudau\u00f0a e\u00f0a frumubreytingum sem yfirleitt m\u00e1 rekja til ska\u00f0a \u00e1 erf\u00f0aefninu, DNA. Ef fj\u00f6ldi frumna sem ska\u00f0ast e\u00f0a deyja er n\u00e6gjanlegur geta aflei\u00f0ingarnar or\u00f0i\u00f0 r\u00f6skun \u00e1 l\u00edff\u00e6rastarfsemi e\u00f0a dau\u00f0i. Einnig getur or\u00f0i\u00f0 ska\u00f0i \u00e1 DNA sem ekki drepur frumurnar. L\u00edkami okkar b\u00fdr yfir \u00e1kve\u00f0inni getu til a\u00f0 lagf\u00e6ra \u00fe\u00e6r skemmdir sem frumur okkar ver\u00f0a fyrir vegna j\u00f3nandi geislunar, en ef geislunin ver\u00f0ur meiri en l\u00edkaminn r\u00e6\u00f0ur vi\u00f0 geta or\u00f0i\u00f0 st\u00f6kkbreytingar \u00ed erf\u00f0aefninu sem geta \u00e1 endanum valdi\u00f0 krabbameini. Ef frumurnar sem st\u00f6kkbreytast eru kynfrumur getur geislunin valdi\u00f0 arfgengum \u00e1hrifum, \u00fe.e. ska\u00f0a \u00ed afkomendum. Eins getur geislun haft \u00e1hrif \u00e1 f\u00f3stur \u00ed m\u00f3\u00f0urkvi\u00f0i. B\u00f6rn eru vi\u00f0kv\u00e6mari fyrir geislun en fullor\u00f0nir, en krabbamein og arfgeng \u00e1hrif geislunar koma oft ekki fram fyrr en eftir langan t\u00edma, jafnvel \u00e1ratugi. F\u00f3lk getur einnig or\u00f0i\u00f0 fyrir br\u00e1\u00f0um eitur\u00e1hrifum ef \u00fea\u00f0 ver\u00f0ur fyrir mikilli j\u00f3nandi geislun \u00e1 stuttum t\u00edma. Br\u00e1\u00f0 eitur\u00e1hrif lei\u00f0a til \u00feess a\u00f0 skemmdirnar ver\u00f0a meiri en l\u00edkaminn r\u00e6\u00f0ur vi\u00f0 a\u00f0 lagf\u00e6ra. D\u00e6mi um \u00feessi \u00e1hrif eru bruni h\u00fa\u00f0ar, \u00f3gle\u00f0i og uppk\u00f6st, h\u00e1rlos og skert frj\u00f3semi.<\/p>\n

\"\"<\/a>

Mynd 6.8. Til vinstri m\u00e1 sj\u00e1 mynd af DNA, en erf\u00f0aefni okkar er vi\u00f0kv\u00e6mt fyrir j\u00f3nandi geislun. H\u00e6gri megin m\u00e1 sj\u00e1 helstu \u00e1hrifasta\u00f0i geislunar \u00ed b\u00f6rnum, en b\u00f6rn eru talsvert vi\u00f0kv\u00e6mari fyrir geislun en fullor\u00f0nir.<\/p><\/div>\n

Til a\u00f0 br\u00e1\u00f0 eitur\u00e1hrif eigi s\u00e9r sta\u00f0 \u00fearf geislunin a\u00f0 n\u00e1 \u00e1kve\u00f0num \u00fer\u00f6skuldi \u00ed stuttan t\u00edma. Alvarleiki einkennanna eykst me\u00f0 vaxandi geislun. Skammtar yfir 50 Gy skemma mi\u00f0taugakerfi\u00f0 \u00fea\u00f0 illa a\u00f0 b\u00faast m\u00e1 vi\u00f0 dau\u00f0a innan nokkurra daga. Skammtar l\u00e6gri en 8 Gy valda geislaveiki en einkenni hennar eru m.a. \u00f3gle\u00f0i, uppk\u00f6st, ni\u00f0urgangur, \u00fearmakrampar, v\u00f6kvatap, \u00fereyta, sinnuleysi, lystarleysi, hiti, h\u00f6fu\u00f0verkur og l\u00e1g\u00fer\u00fdstingur. Einkennin koma fram strax eftir af einstaklingur ver\u00f0ur fyrir geislun. F\u00f3rnarl\u00f6mb geislaveiki \u2013 t.d. sl\u00f6kkvi\u00f0li\u00f0smennirnir \u00ed Chernobyl \u00e1ri\u00f0 1986 \u2013 geta lifa\u00f0 af og jafnvel n\u00e1\u00f0 s\u00e9r af fyrstu einkennunum eftir nokkra daga, en deyja svo e.t.v. 1-2 vikum seinna vegna ska\u00f0a \u00ed meltingarvegi. Ef skammtar eru l\u00e6gri ver\u00f0ur hugsanlega ekki ska\u00f0i \u00ed meltingarvegi en geislunin getur samt valdi\u00f0 dau\u00f0a innan f\u00e1rra m\u00e1na\u00f0a vegna bl\u00f3\u00f0mergsska\u00f0a. H\u00e1ir geislaskammtar auka l\u00edkurnar \u00e1 hjartasj\u00fakd\u00f3mum.<\/p>\n

S\u00ed\u00f0b\u00fain \u00e1hrif l\u00e6gri geislaskammta felast einkum \u00ed hv\u00edtbl\u00e6\u00f0i og krabbameini auk \u00feess sem erf\u00f0agallar geta komi\u00f0 fram \u00ed afkomendum \u00feeirra sem or\u00f0i\u00f0 hafa fyrir geislun. Krabbamein er fl\u00f3ki\u00f0 fyrirb\u00e6ri. A\u00f0 \u00f6llum l\u00edkindum fer ferli\u00f0 af sta\u00f0 vegna atviks sem hefur \u00e1hrif \u00e1 eina e\u00f0a fleiri frumur l\u00edkamans. S\u00ed\u00f0an \u00fearf r\u00f6\u00f0 annarra atbur\u00f0a a\u00f0 ver\u00f0a til a\u00f0 fruman ver\u00f0i illkynja og \u00e6xli myndist. Hv\u00edtbl\u00e6\u00f0i, skjaldkirtils- og beinkrabbamein koma fram hj\u00e1 f\u00f3lki f\u00e1einum \u00e1rum eftir geislun en mun lengri t\u00edma tekur fyrir a\u00f0rar tegundir krabbameins a\u00f0 koma fram. \u00deegar svo langur t\u00edmi l\u00ed\u00f0ur er n\u00e6r \u00f3m\u00f6gulegt a\u00f0 segja fyrir um upprunalega \u00e1st\u00e6\u00f0u krabbameinsins me\u00f0 fullri vissu.<\/p>\n

\"\"<\/a>

Mynd 6.9. Vinstra megin m\u00e1 sj\u00e1 mismunandi afdrif geislavirku sams\u00e6tanna I-131 og Cs-137 \u00ed umhverfinu \u00ed kj\u00f6lfar kjarnorkuslyssins \u00ed Chernobyl. Jo\u00f0 er me\u00f0 stuttan helmingunart\u00edma, e\u00f0a 8 daga, og er \u00fev\u00ed a\u00f0 mestu horfi\u00f0 \u00far umhverfinu innan nokkurra m\u00e1na\u00f0a. Ses\u00edum er hins vegar me\u00f0 tilt\u00f6lulega langan helmingunart\u00edma, 30 \u00e1r, og finnst enn \u00ed talsver\u00f0u magni \u00ed umhverfinu n\u00fa r\u00famlega 30 \u00e1rum eftir slysi\u00f0. H\u00e6gra megin m\u00e1 sj\u00e1 fj\u00f6lda hv\u00edtbl\u00e6\u00f0is- og annarra krabbameinstilfella eftir kjarnorkusprengingarnar \u00ed Hiroshima og Nagasaki \u00e1ri\u00f0 1945.<\/p><\/div>\n

Mikilv\u00e6gustu geislavirku sams\u00e6turnar \u00ed umhverfinu eru pl\u00fat\u00f3n\u00edum (Pu-240), jo\u00f0 (I-131), ses\u00edum (Cs-137), stront\u00edum (Sr-90) og tr\u00edt\u00edum (H-3).<\/p>\n

<\/span><\/em>Pl\u00fat\u00f3n\u00edum (Pu-240)<\/em><\/h6>\n

Pl\u00fat\u00f3n\u00edum er silfurlitur \u00feungm\u00e1lmur. Pl\u00fat\u00f3n\u00edum fyrirfinnst \u00ed s\u00e1ralitlu magni \u00ed n\u00e1tt\u00farunni en styrkur \u00feess hefur aukist \u00fear sem \u00fea\u00f0 var \u00ed sprengjunni sem varpa\u00f0 var \u00e1 Nagasaki og vegna kjarnorkutilrauna, auk \u00feess sem \u00fea\u00f0 losna\u00f0i \u00fat \u00ed andr\u00famslofti\u00f0 \u00ed slysunum \u00ed Chernobyl og Fukushima. Pl\u00fat\u00f3n\u00edum sem hefur losna\u00f0 \u00ed fj\u00f6lm\u00f6rgum kjarnorkutilraunum hefur gerey\u00f0ilagt st\u00f3r landssv\u00e6\u00f0i. Pl\u00fat\u00f3n\u00edum sendir fr\u00e1 s\u00e9r \u03b1-geislun og breytist au\u00f0veldlega \u00ed U-235 sem umbreytist einnig au\u00f0veldlega me\u00f0 tilheyrandi geislun. Helmingunart\u00edmi pl\u00fat\u00f3n\u00edums er 24.000 \u00e1r sem er gr\u00ed\u00f0arlega langt \u00e1 t\u00edmaskala okkar mannf\u00f3lksins \u00fe\u00f3 svo a\u00f0 hann blikni \u00ed samanbur\u00f0i vi\u00f0 helmingunart\u00edma U-235 sem er 700 millj\u00f3n \u00e1r. \u00dev\u00ed \u00fearf a\u00f0 koma pl\u00fat\u00f3n\u00edum fyrir dj\u00fapt \u00ed jar\u00f0l\u00f6gum e\u00f0a brenna \u00fea\u00f0 upp \u00ed kjarnorkuverum. Pl\u00fat\u00f3n\u00edum er mj\u00f6g eitra\u00f0 eins og a\u00f0rir \u00feungm\u00e1lmar, jafnvel eitra\u00f0ra en \u00faran\u00edum. Leysni pl\u00fat\u00f3n\u00edums er hins vegar frekar l\u00e1g og efni\u00f0 hlutfallslega \u00f3hreyfanlegt, \u00fe.e. \u00fea\u00f0 flyst ekki miki\u00f0 til \u00ed umhverfinu. Efni\u00f0 berst frekar inn \u00ed l\u00edkamann me\u00f0 inn\u00f6ndun en me\u00f0 f\u00e6\u00f0u og getur sest \u00e1 bein og l\u00edff\u00e6ri \u00e1 bor\u00f0 vi\u00f0 lifur og lungu. L\u00edffr\u00e6\u00f0ilegur helmingunart\u00edmi \u00feess er nokkrir \u00e1ratugir.<\/p>\n

<\/span><\/em>Jo\u00f0 (I-131)<\/em><\/h6>\n

Jo\u00f0 l\u00edtur \u00fat eins og m\u00e1lmur \u00fer\u00e1tt fyrir a\u00f0 vera hal\u00f3gen. Jo\u00f0 er ekki eins hvarfgjarnt og a\u00f0rir hal\u00f3genar, en frekar rokgjarnt og ver\u00f0ur a\u00f0 fj\u00f3lubl\u00e1rri lofttegund vi\u00f0 uppgufun. Helmingunart\u00edmi I-131 er 8 dagar og \u00fev\u00ed er jo\u00f0 h\u00e1geislavirkt. Jo\u00f0 sendir fr\u00e1 s\u00e9r \u03b3- og \u03b2-geislun. Geislavirkt jo\u00f0 hefur borist \u00ed talsver\u00f0u magni \u00fat \u00ed andr\u00famslofti\u00f0 \u00ed kj\u00f6lfar slysa og kjarnorkutilrauna. Jo\u00f0 er mj\u00f6g hreyfanlegt \u00ed umhverfinu, \u00fea\u00f0 fellur til jar\u00f0ar me\u00f0 geislavirku \u00farfelli, sest \u00e1 lauf plantna og er einnig teki\u00f0 upp af pl\u00f6ntum um r\u00f3tarkerfi. Jo\u00f0, sem fellur \u00e1 gras sem biti\u00f0 er af mj\u00f3lkandi d\u00fdrum, kemur fram \u00ed mj\u00f3lkinni a\u00f0eins nokkrum klukkustundum s\u00ed\u00f0ar. F\u00f3lk er \u00fatsett fyrir geislavirku jo\u00f0i ef \u00fea\u00f0 bor\u00f0ar menga\u00f0ar afur\u00f0ir. Jo\u00f0i\u00f0 sest \u00ed skjaldkirtilinn og getur valdi\u00f0 \u00fear krabbameini og \u00fe\u00e1 er f\u00f3lk sem er me\u00f0 jo\u00f0skort fyrir \u00ed s\u00e9rstaklega mikilli h\u00e6ttu.<\/p>\n

<\/span><\/em>Ses\u00edum (Cs-137)<\/em><\/h6>\n

Ses\u00edum er alkal\u00edm\u00e1lmur. Geislavirkt ses\u00edum myndast vi\u00f0 margs konar kjarnasundrunarhv\u00f6rf og losna\u00f0i t.a.m. \u00ed miklu magni \u00ed Chernobyl-slysinu. Helmingunart\u00edmi ses\u00edums er r\u00e9tt r\u00fam 30 \u00e1r og \u00fea\u00f0 sendir fr\u00e1 s\u00e9r b\u00e6\u00f0i \u03b3- og \u03b2-geislun. Geislavirkt ses\u00edum haf\u00f0i ekki veri\u00f0 \u00ed umhverfinu \u00ed 1,7 milljar\u00f0 \u00e1ra \u00feegar n\u00fdting kjarnorku h\u00f3fst en ses\u00edum er ein helsta \u00e1st\u00e6\u00f0a geislamengunar \u00ed kj\u00f6lfar kjarnorkutilrauna og -slysa. Ses\u00edum mun einnig \u2013 \u00e1samt stront\u00edum og pl\u00fat\u00f3n\u00edum \u2013 ver\u00f0a helsta uppspretta geislunar fr\u00e1 kjarnorku\u00fargangi n\u00e6stu r\u00famlega 100 \u00e1r. Ses\u00edum dreifist ekki jafnau\u00f0veldlega og jo\u00f0. Geislavirkt ses\u00edum berst \u00fe\u00f3 sm\u00e1m saman \u00ed jar\u00f0veg og er teki\u00f0 upp af pl\u00f6ntum og getur \u00fev\u00ed borist \u00ed f\u00e6\u00f0uke\u00f0juna. Vegna tilt\u00f6lulega langs helmingunart\u00edma er \u00fea\u00f0 marga \u00e1ratugi \u00ed umhverfinu \u00e1 me\u00f0an geislavirkt jo\u00f0 er a\u00f0 mestu horfi\u00f0 innan nokkurra m\u00e1na\u00f0a. Ses\u00edum heg\u00f0ar s\u00e9r l\u00edkt og kal\u00edum og er teki\u00f0 upp af v\u00f6\u00f0vum l\u00edkamans.<\/p>\n

<\/span><\/em>Stront\u00edum (Sr-90)<\/em><\/h6>\n

Stront\u00edum er jar\u00f0alkal\u00edm\u00e1lmur. Geislavirkt stront\u00edum (Sr-90) er \u00e1samt Cs-137 eitt mikilv\u00e6gasta efni\u00f0 sem myndast vi\u00f0 kjarnasundrunarhv\u00f6rf og losna\u00f0i t.a.m. \u00ed miklu magni \u00ed slysunum \u00ed Chernobyl og Fukushima. Helmingunart\u00edmi Sr-90 er um 29 \u00e1r. \u00dea\u00f0 sendir fr\u00e1 s\u00e9r \u03b2-geislun. Stront\u00edum dreifist minna en ses\u00edum vegna \u00feess a\u00f0 \u00fea\u00f0 er ekki eins rokgjarnt. \u00dear sem stront\u00edum sendir ekki fr\u00e1 s\u00e9r \u03b3-geislun er erfitt a\u00f0 m\u00e6la \u00fea\u00f0 \u00ed umhverfinu og \u00fev\u00ed er heg\u00f0un \u00feess ekki vel kortl\u00f6g\u00f0. Stront\u00edum sendir fr\u00e1 s\u00e9r \u03b2-geislun me\u00f0 stutta dr\u00e6gni og er \u00fev\u00ed h\u00e6ttulegt ef \u00fea\u00f0 kemst \u00ed l\u00edkamann me\u00f0 f\u00e6\u00f0u e\u00f0a inn\u00f6ndum. Stront\u00edum heg\u00f0ar s\u00e9r l\u00edkt og kals\u00edum. Efni\u00f0 er teki\u00f0 upp af beinum l\u00edkamans og getur valdi\u00f0 beinkrabbameini e\u00f0a hv\u00edtbl\u00e6\u00f0i ef m\u00e6nan ver\u00f0ur fyrir geislun. Stront\u00edum barst me\u00f0 mengu\u00f0u vatni \u00ed sj\u00f3inn vi\u00f0 Fukushima eftir slysi\u00f0 \u00fear. Hreinsib\u00fana\u00f0urinn sem hreinsar geislavirkar sams\u00e6tur \u00far mengu\u00f0u vatninu haf\u00f0i hreinsa\u00f0 ses\u00edum \u00far vatninu \u00ed \u00fe\u00f3nokkurn t\u00edma \u00e1\u00f0ur en hreinsun \u00e1 stront\u00edum h\u00f3fst.<\/p>\n

<\/span><\/em>Tr\u00edt\u00edum (H-3)<\/em><\/h6>\n

Tr\u00edt\u00edum er vetnissams\u00e6ta me\u00f0 tveimur nifteindum. Miki\u00f0 magn tr\u00edt\u00edummenga\u00f0s vatns hefur falli\u00f0 til eftir slysi\u00f0 \u00ed Fukushima. Helmingunart\u00edmi tr\u00edt\u00edums er 12,3 \u00e1r. \u00dea\u00f0 sendir fr\u00e1 s\u00e9r \u03b2-geislun en orka geislunarinnar er mj\u00f6g l\u00edtil. Tr\u00edt\u00edum er mj\u00f6g hreyfanlegt \u00ed umhverfinu. \u00dea\u00f0 getur bundist s\u00farefni og mynda\u00f0 vatn og kemst \u00fev\u00ed au\u00f0veldlega \u00ed l\u00edkama manna. L\u00edffr\u00e6\u00f0ilegur helmingunart\u00edmi \u00ed l\u00edkamanum er hins vegar a\u00f0eins 10 dagar, sem \u00fe\u00fd\u00f0ir a\u00f0 \u00fea\u00f0 skolast frekar hratt \u00fat. Vegna \u00feessa stutta helmingunart\u00edma og \u00feess hve orka geislunarinnar er l\u00edtil \u2013 auk \u00feess sem tr\u00edt\u00edum sendir ekki fr\u00e1 \u03b3-geislun \u2013 eru eitur\u00e1hrif \u00feess tilt\u00f6lulega l\u00edtil. Hreinsib\u00fana\u00f0urinn sem hreinsar geislavirkar sams\u00e6tur \u00far mengu\u00f0u vatni \u00ed Fukushima n\u00e6r ekki a\u00f0 hreinsa tr\u00edt\u00edum \u00far vatninu \u00fear sem sameindin er svo l\u00edtil. Geislavirkt tr\u00edt\u00edum hefur \u00fev\u00ed borist \u00ed talsver\u00f0u m\u00e6li \u00ed Kyrrahafi\u00f0 eftir slysi\u00f0.<\/p>\n

 <\/p>\n","protected":false},"excerpt":{"rendered":"

Geislavirk efni hafa veri\u00f0 hluti af n\u00e1tt\u00farulegu umhverfi \u00e1 j\u00f6r\u00f0inni fr\u00e1 upphafi. \u00deau senda fr\u00e1 s\u00e9r svokalla\u00f0a j\u00f3nandi geislun, \u00fe.e. geislun sem hefur n\u00e6ga orku til a\u00f0 r\u00edfa rafeind fr\u00e1 frumeind, en sl\u00edkt getur m.a. ska\u00f0a\u00f0 erf\u00f0aefni frumna (DNA). Vi\u00f0 Lesa meira…<\/a><\/p>\n","protected":false},"author":2,"featured_media":1751,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[26],"tags":[],"class_list":["post-1682","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-6-geislavirkni"],"_links":{"self":[{"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/posts\/1682","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/comments?post=1682"}],"version-history":[{"count":18,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/posts\/1682\/revisions"}],"predecessor-version":[{"id":4045,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/posts\/1682\/revisions\/4045"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/media\/1751"}],"wp:attachment":[{"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/media?parent=1682"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/categories?post=1682"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/tags?post=1682"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}