{"id":21860,"date":"2015-04-01T17:27:03","date_gmt":"2015-04-01T14:27:03","guid":{"rendered":"https:\/\/bilimvegelecek.com.tr\/?p=21860"},"modified":"2021-01-24T14:19:51","modified_gmt":"2021-01-24T11:19:51","slug":"buyuk-deprem-tsunami-ve-nukleer-santral-kazasindan-4-yil-sonra-fukusimada-durum-psikolojik-sosyal-sorunlar-ve-kimi-dersler","status":"publish","type":"post","link":"https:\/\/bilimvegelecek.com.tr\/index.php\/2015\/04\/01\/buyuk-deprem-tsunami-ve-nukleer-santral-kazasindan-4-yil-sonra-fukusimada-durum-psikolojik-sosyal-sorunlar-ve-kimi-dersler","title":{"rendered":"B\u00fcy\u00fck deprem, tsunami ve n\u00fckleer santral kazas\u0131ndan 4 y\u0131l sonra\u00a0Fuku\u015fima\u2019da durum, psikolojik-sosyal sorunlar ve kimi dersler"},"content":{"rendered":"

D\u00fcnya Sa\u011fl\u0131k \u00d6rg\u00fct\u00fc\u2019n\u00fcn Cenevre\u2019de sundu\u011fu, 30 kadar ba\u011f\u0131ms\u0131z uzman taraf\u0131ndan haz\u0131rlanan bilimsel raporda, kanser riskinin, Fuki\u015fima Santral\u0131n\u0131n 20-30 km \u00e7evresi d\u0131\u015f\u0131nda \u00e7ok az artt\u0131\u011f\u0131 a\u00e7\u0131klan\u0131yor. Uzmanlar, buna ra\u011fmen, buralarda ya\u015fayanlar\u0131n, uzun s\u00fcre g\u00f6zlem alt\u0131nda bulundurulmas\u0131n\u0131 \u00f6neriyor. Kanser hastal\u0131klar\u0131n\u0131n b\u00fcy\u00fck oranda artaca\u011f\u0131 beklenmese de, baz\u0131 kanser t\u00fcrleri ve Fuku\u015fima \u00e7evresindeki 1-2 yerle\u015fim yerindekiler i\u00e7in riskin artt\u0131\u011f\u0131 ileri s\u00fcr\u00fclerek, buralarda ya\u015fayanlar\u0131n uzun s\u00fcre g\u00f6zlem alt\u0131nda bulundurulmas\u0131 gerekti\u011fi vurgulan\u0131yor. <\/em><\/p>\n

11 Mart 2011\u2019deki b\u00fcy\u00fck deprem ve tsunaminin tetikledi\u011fi Fuku\u015fima n\u00fckleer santral kazas\u0131n\u0131n ard\u0131ndan 4 y\u0131l ge\u00e7ti. Bu arada s\u00fcregelen \u00e7ok y\u00f6nl\u00fc, yo\u011fun bilimsel ve teknolojik ara\u015ft\u0131rmalarla elde edilen bulgu, bilgi ve de\u011ferlendirmelere g\u00f6re neler biliyoruz? \u00d6zellikle yurdumuzda yap\u0131m\u0131na ba\u015flanan n\u00fckleer santrallar ve \u00e7evrelerinde ya\u015fayan halkla ilgili olarak Fuku\u015fima\u2019dan al\u0131nacak dersler nelerdir?<\/p>\n

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6 reakt\u00f6r bloklu Fuku\u015fima N\u00fckleer Santral\u0131 ve \u00e7evresinin kazadan \u00f6nceki g\u00f6r\u00fcn\u00fcm\u00fc.<\/figcaption><\/figure>\n

B\u00fcy\u00fck deprem ve tsunami sonucu Japonya\u2019n\u0131n kuzeydo\u011fu k\u0131y\u0131lar\u0131nda ya\u015fayan halktan 380.000 ki\u015fi yerle\u015fim yerlerinden uzakla\u015ft\u0131r\u0131ld\u0131. Bunlardan 130.000 kadar\u0131, Fuku\u015fima Daiichi N\u00fckleer Santrallar\u0131 \u00e7evresindendi. Deprem ve tsunamide ya\u015fam\u0131n\u0131 yitirenlerin say\u0131s\u0131n\u0131n 16.000 ve kaybolanlar\u0131n da 3.200 ki\u015fi dolay\u0131nda oldu\u011fu biliniyor. Fuku\u015fima N\u00fckleer Santrallar\u0131n\u0131n 20 km \u00e7evresinde ya\u015fayan halk\u0131n neredeyse t\u00fcm\u00fc, kazadan hemen sonra bo\u015falt\u0131ld\u0131\u011f\u0131ndan, burada daha \u00f6nce oturanlara, Fuku\u015fima radyasyonunun do\u011frudan bir etkisi olmam\u0131\u015f oldu. Kazan\u0131n birka\u00e7 g\u00fcn sakland\u0131\u011f\u0131 1986\u2019daki \u00c7ernobil kazas\u0131nda ise, yak\u0131ndaki halk hemen bo\u015falt\u0131lmad\u0131\u011f\u0131ndan orada ya\u015fayan \u00e7ocuklarda sonradan tiroid kanseri ortaya \u00e7\u0131km\u0131\u015ft\u0131. Fuku\u015fima N\u00fckleer Santrallar\u0131ndaki kazalar sonucu radyasyonun etkisiyle bug\u00fcne kadar herhangi bir ki\u015fin \u00f6ld\u00fc\u011f\u00fc belirlenemedi. Herhangi bir \u00f6l\u00fcm, kaza sonras\u0131 kurtarma, bak\u0131m ve onar\u0131m personeli aras\u0131nda da olmad\u0131. Ancak n\u00fckleer santrallar\u0131n yak\u0131n ve uzak \u00e7evresinde daha \u00f6nce ya\u015fayan 130.000 ki\u015fi, \u00e7evredeki toprak, bitki ve evlere radyoaktif madde bula\u015fmas\u0131 sonucu, ba\u015fka yerlere g\u00f6\u00e7 etmek zorunda b\u0131rak\u0131ld\u0131lar. \u00d6zellikle bunlar aras\u0131nda, radyasyonun etkisiyle, kendilerinin ya da \u00e7ocuklar\u0131n\u0131n kansere yakalan\u0131p \u00f6leceklerini d\u00fc\u015f\u00fcnen, depresyon\/travma (ruhsal bozukluk, \u00e7\u00f6k\u00fcnt\u00fc) ge\u00e7iren ki\u015filerden 1000\u2019den fazlas\u0131n\u0131n \u00f6ld\u00fc\u011f\u00fc ve baz\u0131lar\u0131n\u0131n da ya\u015fam\u0131na son verdi\u011fi gazete haberlerinde yer alm\u0131\u015f ise de, bu \u00f6l\u00fcmlerin ger\u00e7ek nedenlerinin Fuku\u015fima kazas\u0131na ba\u011flanabilece\u011fi kan\u0131tlanm\u0131\u015f de\u011fil.<\/p>\n

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Kaza g\u00fcnlerinde 1, 3 ve 4 nolu reakt\u00f6rlerdeki hidrojen patlamalar\u0131.<\/figcaption><\/figure>\n

\u0130leride radyasyon kazalar\u0131n\u0131n toplumda psikolojik bozukluklara yol a\u00e7mamas\u0131 i\u00e7in, halk\u0131n radyasyon konusunda bilgilendirilmesinin \u00e7ok \u00f6nemli oldu\u011funu, gerekli haz\u0131rl\u0131klar\u0131n \u00e7ok \u00f6nceden yap\u0131lmas\u0131 gere\u011fini, uluslararas\u0131 kurumlar vurguluyorlar.(1, 2)<\/sup><\/p>\n

Bu yaz\u0131da Fuku\u015fima \u00e7evresinde ve Japonya\u2019da, kazadan bu yana ge\u00e7en 4 y\u0131l boyunca, \u00f6zellikle uluslararas\u0131 yetkili kurumlar\u0131n ara\u015ft\u0131rmalar\u0131na dayanan g\u00f6zlem ve \u00f6l\u00e7\u00fcmlerle elde edilen bulgu ve bilgileri, \u00f6zetle, kendi d\u00fc\u015f\u00fcncelerimizi katmadan, oldu\u011fu gibi yans\u0131tmaya \u00e7al\u0131\u015faca\u011f\u0131z.<\/p>\n

\u00dc\u00e7l\u00fc karay\u0131k\u0131m (felaket), ba\u015flang\u0131\u00e7taki durum ve al\u0131nan \u00f6nlemler<\/strong><\/p>\n

11 Mart 2011 g\u00fcn\u00fc Japonya\u2019n\u0131n kuzeydo\u011fusundaki b\u00f6lgede \u00fc\u00e7l\u00fc karay\u0131k\u0131m ya\u015fand\u0131: \u00d6nce, o g\u00fcne kadar kay\u0131tlara hi\u00e7 ge\u00e7memi\u015f 9 b\u00fcy\u00fckl\u00fc\u011f\u00fcnde \u00e7ok b\u00fcy\u00fck bir deprem, ard\u0131ndan bu b\u00fcy\u00fck depremin tetikledi\u011fi tsunami ve bunun da yol a\u00e7t\u0131\u011f\u0131 Fuku\u015fima Daiichi N\u00fckleer Santrallar\u0131ndaki patlamalarla, o g\u00fcnlerde TV\u2019lerde s\u0131k s\u0131k izlenen, b\u00fcy\u00fck kaza. Deprem ve tsunami sonucu 1 milyon kadar bina y\u0131k\u0131ld\u0131 ya da oturulamaz duruma geldi.<\/p>\n

Depremin hemen \u00f6ncesine kadar Fuku\u015fima Daiichi\u2019deki 6 reakt\u00f6rden ilk 3\u2019\u00fc \u00e7al\u0131\u015fmakta, elektrik \u00fcretmekteydi. Di\u011fer 3 reakt\u00f6r, \u201cyak\u0131t elemanlar\u0131 de\u011fi\u015ftirme s\u00fcrecinde\u201d oldu\u011fundan \u00e7al\u0131\u015fm\u0131yordu. 4 no\u2019lu reakt\u00f6r kazan\u0131nda ise, yak\u0131t elemanlar\u0131 yoktu, bunlar bekletme havuzundayd\u0131.<\/p>\n

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11 Mart 2011\u2019deki tsunamiden sonra, radyoaktif maddelerle bula\u015fm\u0131\u015f b\u00f6lgede arama yapan koruma giysili g\u00f6revliler.<\/figcaption><\/figure>\n

9 b\u00fcy\u00fckl\u00fc\u011f\u00fcndeki depremin hemen ard\u0131ndan Fuku\u015fima N\u00fckleer Reakt\u00f6rlerinin \u00e7evredeki elektrik a\u011f\u0131yla, y\u00fcksek gerilim hatlar\u0131n\u0131n depremde kopmas\u0131, direklerin baz\u0131lar\u0131n\u0131n y\u0131k\u0131lmas\u0131 sonucu, ba\u011flant\u0131s\u0131 kesildi. Bu nedenle, reakt\u00f6rlere su basan pompalara d\u0131\u015fardan elektrik sa\u011flanamad\u0131. O an \u00e7al\u0131\u015fmakta olan ilk \u00fc\u00e7 reakt\u00f6rde, n\u00fckleer zincirleme tepkime, reakt\u00f6rlerin otomatik \u201ch\u0131zla durdurma sistemi\u201dyle kesildi. Depremin hemen ard\u0131ndan gelen tsunami dalgalar\u0131, k\u0131y\u0131daki 10 m y\u00fcksekli\u011findeki koruyucu duvar\u0131 a\u015farak, santral\u0131n alt katlar\u0131nda bulunan ivedi elektrik \u00fcrete\u00e7lerini sular alt\u0131nda b\u0131rak\u0131p i\u015flemez duruma getirince, \u0131s\u0131 yaymay\u0131 s\u00fcrd\u00fcren reakt\u00f6rlerdeki ve \u201ckullan\u0131lm\u0131\u015f yak\u0131t elemanlar\u0131 bekletme havuzlar\u0131\u201dndaki n\u00fckleer yak\u0131t elemanlar\u0131 bir s\u00fcre so\u011futulamad\u0131. \u00c7al\u0131\u015fan tek bir ivedi sistemle (dizel jenerat\u00f6rle) 5 ve 6 nolu reakt\u00f6rler ancak so\u011futulabildi. \u00d6zetle, deprem ve tsunami sonucu ilk 4 reakt\u00f6r\u00fcn elektriksiz kal\u0131p so\u011futulamamas\u0131, Fuku\u015fima n\u00fckleer kazas\u0131n\u0131 olu\u015fturmu\u015f oldu. Bu reakt\u00f6rlerin yak\u0131t elemanlar\u0131nda farkl\u0131 b\u00fcy\u00fckl\u00fckte bozulma ve ergime olu\u015ftu (Bug\u00fcn Fuku\u015fima\u2019da reakt\u00f6rlerin t\u00fcm\u00fc art\u0131k d\u0131\u015f elektrik a\u011f\u0131ndan besleniyor).<\/p>\n

12-15 Mart 2011 g\u00fcnleri aras\u0131nda ilk d\u00f6rt reakt\u00f6rdeki patlamalar sonucu reakt\u00f6r binalar\u0131ndan havaya y\u00fckselen beyaz duman, televizyonlarda s\u0131k s\u0131k g\u00f6sterilirken, bunlara yabanc\u0131 olan halk aras\u0131nda, reakt\u00f6r ya da atom patlamas\u0131 \u015feklinde bir izlenim b\u0131rakt\u0131. Bunlar\u0131n sonradan, hidrojen gaz\u0131 patlamas\u0131 oldu\u011fu anla\u015f\u0131ld\u0131 ve yetkililerce a\u00e7\u0131kland\u0131. Yak\u0131t elemanlar\u0131 \u00e7ubuklar\u0131n\u0131n k\u0131l\u0131flar\u0131ndaki zirkonyumun \u00e7ok y\u00fcksek s\u0131cakl\u0131kta reakt\u00f6r so\u011futma suyuyla tepkimeye girmesiyle hidrojen gaz\u0131 olu\u015fuyor. Patlayabilen hidrojen gaz\u0131 kar\u0131\u015f\u0131m\u0131n\u0131n olu\u015fmas\u0131n\u0131n s\u00fcrmesini \u00f6nlemek i\u00e7in, daha sonra, ilk 3 reakt\u00f6r binas\u0131nda zorunlu \u00f6nlemler al\u0131nd\u0131, binalar\u0131n havas\u0131na azot gaz\u0131 pompaland\u0131. 5 ve 6 numaral\u0131 reakt\u00f6rlerde ise reakt\u00f6r binalar\u0131n\u0131n \u00e7at\u0131s\u0131nda delikler a\u00e7\u0131larak hidrojen gaz\u0131 birikimi \u00f6nlendi.
\nJapon yetkili kurumu, Fuku\u015fima kazas\u0131n\u0131 12 Mart 2011 g\u00fcn\u00fc \u201cciddi kaza\u201d (kaza s\u0131n\u0131f\u0131 3) olarak s\u0131n\u0131fland\u0131rd\u0131ktan sonra, 12 Nisan 2011\u2019de \u201cfelaket\/karay\u0131k\u0131m\u201d s\u0131n\u0131f\u0131na y\u00fckseltti (kaza s\u0131n\u0131f\u0131 7).<\/p>\n

1970\u2019li y\u0131llar\u0131n, General Electric yap\u0131m\u0131, Fuku\u015fima N\u00fckleer Santral\u0131 zaten sorunluydu<\/strong><\/p>\n

Tokyo\u2019nun 250 km kuzeydo\u011fusundaki Pasifik Okyanusu k\u0131y\u0131s\u0131nda kurulmu\u015f olan 6 reakt\u00f6r bloklu Fuku\u015fima N\u00fckleer Santrallar\u0131 General Electric (GE) yap\u0131m\u0131yd\u0131 ve bunlar\u0131 TEPCO \u015firketi i\u015fletiyordu. Reakt\u00f6rlerin t\u00fcm\u00fc kaynamal\u0131 sulu cinsten reakt\u00f6rlerdi ve kaza ge\u00e7iren ilk 4\u2019\u00fc 760 MWe<\/sub> (elektriksel) g\u00fc\u00e7teydi. Kaza olmayan son 2 reakt\u00f6r 1067 ve 1325 MWe<\/sub> <\/strong>g\u00fcc\u00fcndeydiler. \u0130lk 4 reakt\u00f6r Mark 1 denen g\u00fcvenlik kab\u0131yla (containment) \u00e7evriliydi (Bkz \u00c7izim). Mark 1\u2019in, bir kaza durumunda y\u00fcksek bas\u0131nca dayanamayaca\u011f\u0131n\u0131, bas\u0131n\u00e7 d\u00fc\u015f\u00fcr\u00fclme sisteminin Mark 1\u2019de bulunmad\u0131\u011f\u0131n\u0131, ABD Atom Enerjisi Kurumunun uzmanlar\u0131 daha 1970\u2019li y\u0131llardaki raporlar\u0131nda a\u00e7\u0131klam\u0131\u015flard\u0131 ve bu tip g\u00fcvenlik kab\u0131n\u0131n yasaklanmas\u0131n\u0131 istemi\u015flerdi. Ama bu raporlar g\u00f6z \u00f6n\u00fcne al\u0131n\u0131p gerekli \u00f6nlemler al\u0131nmad\u0131, de\u011fi\u015fiklikler yap\u0131lmad\u0131; ilgili bas\u0131n\u00e7 d\u00fc\u015f\u00fcrme sistemi kurulmadan reakt\u00f6rler i\u015fletmeye a\u00e7\u0131ld\u0131.<\/p>\n

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Fuku\u015fima reakt\u00f6r\u00fc (d\u0131\u015fta g\u00fcvenlik kab\u0131-containment, i\u00e7te reakt\u00f6r kazan\u0131, reakt\u00f6r so\u011futma suyu borular\u0131 ve buhar \u00fcrete\u00e7leri).<\/figcaption><\/figure>\n

1985\u2019de ABD N\u00fckleer D\u00fczenleme Kurulu (USA Nuclear Regulatory Commission), Mark 1\u2019in bir reakt\u00f6r kazas\u0131nda yak\u0131t elemanlar\u0131n\u0131n ergimesi sonucu olu\u015facak bas\u0131nca, y\u00fczde 90 olas\u0131l\u0131kla dayanamayaca\u011f\u0131n\u0131 a\u00e7\u0131klad\u0131. Fuku\u015fima\u2019da bu g\u00f6z \u00f6n\u00fcne al\u0131narak Mark 1\u2019in g\u00fcvenlik kab\u0131na bas\u0131n\u00e7l\u0131 havan\u0131n at\u0131laca\u011f\u0131 subaplar konmu\u015f ise de, kaza s\u0131ras\u0131nda, radyoaktif maddeli buhar hem buralardan hem de hidrojen gaz\u0131 patlamalar\u0131 sonucu \u00e7at\u0131da a\u00e7\u0131lan deliklerden filtrelenmeden d\u0131\u015far\u0131 at\u0131ld\u0131.<\/p>\n

Ayr\u0131ca, b\u00fcy\u00fck bir kaza durumunda pompalar\u0131n \u00e7al\u0131\u015ft\u0131r\u0131lmas\u0131yla reakt\u00f6rlerin so\u011futulmas\u0131n\u0131 sa\u011flayacak olan ivedi elektrik \u00fcrete\u00e7leri (dizel jenerat\u00f6rler) sular\u0131n her an basabilece\u011fi yeralt\u0131 kat\u0131na yerle\u015ftirilmi\u015flerdi; ki 2011\u2019deki tsunami, bunlar\u0131 su alt\u0131nda b\u0131rakarak \u00e7al\u0131\u015ft\u0131r\u0131lamaz duruma getirdi\u011finden kazalar olu\u015fmu\u015ftu. Bunlar\u0131n yerlerinin de\u011fi\u015ftirilmesi birka\u00e7 kez \u00f6nerilmi\u015f olmas\u0131na ra\u011fmen ek gider getirece\u011finden yap\u0131lmam\u0131\u015ft\u0131.<\/p>\n

\u00d6te yandan 2002 y\u0131l\u0131nda, TEPCO elemanlar\u0131n\u0131n g\u00fcvenlik raporlar\u0131n\u0131 16 y\u0131l boyunca de\u011fi\u015ftirerek \u00f6nemli bozukluk ve kazalar\u0131 gizledikleri, d\u00fczmece raporlar haz\u0131rlad\u0131klar\u0131 ortaya \u00e7\u0131k\u0131nca, Fuku\u015fima santrallar\u0131 bir s\u00fcre durdurularak kontroller yap\u0131lm\u0131\u015f, ancak 2003 y\u0131l\u0131nda santrallar tekrar \u00e7al\u0131\u015ft\u0131r\u0131lm\u0131\u015ft\u0131.<\/p>\n

Kazadan 10 g\u00fcn \u00f6nce, 1 Mart 2011\u2019de yap\u0131lan kontrollerde, 33 aletin, so\u011futma pompalar\u0131n\u0131n ve dizel jenerat\u00f6rlerinin 11 y\u0131ld\u0131r bak\u0131mlar\u0131n\u0131n iyice yap\u0131lmad\u0131\u011f\u0131, bunlar i\u015fletildi\u011finde sorunlar \u00e7\u0131kaca\u011f\u0131 da belirlenmi\u015fti.(3, 4, 5)<\/sup> K\u0131sacas\u0131, Fuku\u015fima N\u00fckleer Santrallar\u0131nda kaza \u201cgeliyorum\u201d diyordu.<\/p>\n

Reakt\u00f6rlerden havaya sal\u0131nan radyoaktif maddeler <\/strong><\/p>\n

Japon yetkililer, Haziran 2011\u2019de reakt\u00f6rlerin \u00e7evredeki havaya 1,5 x 1016 <\/sup><\/strong>Bq Cs 137 radyoaktivitesi yayd\u0131\u011f\u0131n\u0131 a\u00e7\u0131klad\u0131. Bu de\u011fer, \u00c7ernobil\u2019den sal\u0131nan\u0131n d\u00f6rtte biri kadar.<\/p>\n

\u00d6te yandan, Norve\u00e7li ara\u015ft\u0131rmac\u0131lar\u0131n \u00f6nderli\u011finde yap\u0131lan ve 2012\u2019de yay\u0131mlanan uluslararas\u0131 bir bilimsel ara\u015ft\u0131rma raporunda, Fuku\u015fima\u2019dan bunun iki kat\u0131ndan daha \u00e7ok Cs 137\u2019nin \u00e7evreye sal\u0131nd\u0131\u011f\u0131 a\u00e7\u0131klan\u0131yor ki, bu miktar \u00c7ernobil\u2019dekinin yar\u0131s\u0131 kadar. \u00c7evreye sal\u0131nan Xe 133 miktar\u0131 ise bu \u00e7al\u0131\u015fmaya g\u00f6re \u00c7ernobil\u2019dekinden de fazla. Ancak, asal gaz olan Xe 133 v\u00fccutta birikmiyor. Bu sonraki ara\u015ft\u0131rman\u0131n bilimsel y\u00f6ntemi ve sonu\u00e7lar\u0131 hen\u00fcz ilgili otoritelerce incelenip onaylanm\u0131\u015f de\u011fil.<\/p>\n

\u00d6te yandan 11-14 Mart aras\u0131 okyanusa do\u011fru esen r\u00fczg\u00e2rla radyoaktif maddeler denize ta\u015f\u0131nd\u0131lar. 14 Mart\u2019ta r\u00fczg\u00e2r\u0131n denizden karaya esmesi sonucu k\u0131y\u0131 \u015feridindeki yerle\u015fim yerlerinin havas\u0131na (Tokyo b\u00f6lgesi dahil) radyoaktif maddeler ta\u015f\u0131nm\u0131\u015f ise de, o g\u00fcnlerde ya\u011f\u0131\u015f olmamas\u0131 nedeniyle, bunlar havadan yere inmemi\u015f ve yerle\u015fim yerlerinde etkili olmam\u0131\u015flard\u0131r. Radyoaktif maddelerden sadece ya\u011f\u0131\u015f alan baz\u0131 da\u011fl\u0131k b\u00f6lgeler etkilenmi\u015ftir.<\/p>\n

\"\"B\u00fcy\u00fck depremde otomatik olarak durdurulan ilk 3 n\u00fckleer santraldan, tsunaminin etkisiyle u\u011frad\u0131\u011f\u0131 kaza sonucu o g\u00fcnlerden bug\u00fcne kadar sal\u0131nan radyoaktif madde miktar\u0131n\u0131 do\u011frudan \u00f6l\u00e7me ya da belirleme olana\u011f\u0131 bulunmuyor. Bu nedenle, \u00e7evreye ve daha uzaklara yay\u0131lm\u0131\u015f radyoaktif madde miktarlar\u0131n\u0131n belirlenmesi ve ayr\u0131nt\u0131l\u0131 hesaplanmas\u0131yla, santrallardan sal\u0131nan radyoaktif madde miktarlar\u0131n\u0131 kestirmek gerekiyor ki, bu \u00e7ok y\u00f6nl\u00fc ara\u015ft\u0131rma ve \u00f6l\u00e7\u00fcmler de hi\u00e7 kolay de\u011fil. Bir dizi \u00e7al\u0131\u015fma grubu, radyoaktif maddelerden etkilenen b\u00f6lgelerde \u00f6l\u00e7\u00fcm ve de\u011ferlendirmeler yaparak, yo\u011fun ve karma\u015f\u0131k model hesaplamalar\u0131yla, santrallardan yay\u0131lan radyoaktiviteyle ilgili kestirimlerde bulunuyor.<\/p>\n

\u00c7izelge 1\u2019de, UNSCEAR\u2019\u0131n (Uluslararas\u0131 Radyasyondan Korunma Kurulu) yay\u0131mlad\u0131\u011f\u0131(1)<\/sup>, santrallardan sal\u0131nan \u00f6nemli iki radyoaktif madde olan Iyot 131 ve Sezyum 137 miktarlar\u0131 g\u00f6steriliyor. Bu yeni \u00e7al\u0131\u015fmaya g\u00f6re, Fuku\u015fima\u2019dan sal\u0131nan radyoaktif madde miktarlar\u0131n\u0131n, \u00c7ernobil\u2019den sal\u0131nan miktarlar\u0131n y\u00fczde 10\u2019u ile y\u00fczde 20\u2019si aras\u0131nda oldu\u011fu hesaplan\u0131yor.<\/p>\n

Topraktaki radyoaktif maddeler (radyoizotoplar) ve insana etkisi<\/strong><\/p>\n

Fuku\u015fima\u2019daki kazada reakt\u00f6r bloklar\u0131ndan havaya sal\u0131nan radyoaktif maddeler, ya\u011f\u0131\u015flarla ve kuru serpintilerle (hava durumuna g\u00f6re az ya da \u00e7ok miktarlarda), Fuku\u015fima b\u00f6lgesiyle daha uzaklardaki b\u00f6lgelerde topra\u011fa ve bitki \u00f6rt\u00fcs\u00fcne indi. Bunlar i\u00e7inde insan v\u00fccuduna etkisi y\u00f6n\u00fcnden en \u00f6nemlileri I 131, Cs 134 ve Cs 137\u2019dir. 8 g\u00fcnl\u00fck k\u0131sa yar\u0131lanma s\u00fcresiyle ancak ilk 7-8 haftada etkili olabilen I 131, daha sonraki s\u00fcrede etkisini t\u00fcm\u00fcyle yitirmi\u015ftir (Yar\u0131lanma s\u00fcresi: Bir radyoaktif maddenin kendili\u011finden bozunarak yar\u0131ya inmesine kadar ge\u00e7en zaman). 2 y\u0131ll\u0131k yar\u0131lanma s\u00fcresiyle Cs 134 etkisini az da olsa daha 15 y\u0131l kadar s\u00fcrd\u00fcrecektir. \u0130nsan\u0131 200 y\u0131l kadar (gitgide azalarak da olsa) etkileyebilecek olan 30 y\u0131ll\u0131k yar\u0131lanma s\u00fcreli Cs 137 ise, topra\u011fa, bitki \u00f6rt\u00fcs\u00fcne, yerle\u015fim yerlerindeki binalara, parklara vb. bula\u015fm\u0131\u015f en \u00f6nemli radyoizotoptur. \u0130nsan v\u00fccudu i\u00e7in yap\u0131lan doz hesaplar\u0131nda en b\u00fcy\u00fck katk\u0131 ilk haftalarda I 131\u2019den, daha sonraki s\u00fcrede ise Cs 137\u2019den kaynaklan\u0131yor.<\/p>\n

\"\"
Haritada kilo-Bequerel\/m2 olarak topraktaki Cs 137 miktarlar\u0131 g\u00f6steriliyor. Bu \u00f6l\u00e7\u00fcmler helikopterden yap\u0131lm\u0131\u015ft\u0131r (Kaynak: Japonya ilgili Bakanl\u0131\u011f\u0131 METI). Haritada Cs 137\u2019nin Fuku\u015fima\u2019dan uzaklara do\u011fru (k\u0131rm\u0131z\u0131, sar\u0131, ye\u015filden\u2026 kahverengiye do\u011fru azalarak) toprak y\u00fczeyindeki da\u011f\u0131l\u0131m\u0131 g\u00f6steriliyor. Santral yak\u0131ndaki k\u00fc\u00e7\u00fck bir alanda, (k\u0131rm\u0131z\u0131: 10.000 kBq\/ m2, sar\u0131: 1.000 kBq\/ m2 d\u00fczeyinde) topraktaki Cs 137 radyoaktivitesini g\u00f6steriyor. Kahverengi geni\u015f b\u00f6lgede ise, topra\u011f\u0131n radyoaktivitesi 20 ile 60 kBq\/ m2 aras\u0131nda olup epey d\u00fc\u015f\u00fckt\u00fcr.<\/figcaption><\/figure>\n

Topraktaki Cs 137\u2019nin yay\u0131nlad\u0131\u011f\u0131 gama \u0131\u015f\u0131nlar\u0131yla (662 keV enerjide), yak\u0131nlarda bulunanlar do\u011frudan \u0131\u015f\u0131nlanabilirler. V\u00fccutta olu\u015facak radyasyon dozu, topraktaki Cs 137 miktar\u0131na, insan\u0131n toprak y\u00fczeyine yak\u0131nl\u0131\u011f\u0131na ve orada kalma s\u00fcresine g\u00f6re de\u011fi\u015fiyor.<\/p>\n

Topra\u011f\u0131n Cs 137 ile 1000 kBq\/m2<\/sup>\u2019lik kirlenmesi ilk y\u0131lda, topraktan do\u011frudan \u0131\u015f\u0131nlama yoluyla v\u00fccutta 13 mSv\u2019lik etkin doz olu\u015ftururken, bu miktar ikinci y\u0131lda 6 ve \u00fc\u00e7\u00fcnc\u00fc y\u0131lda da 4 mSv\u2019lik etkin doza kar\u015f\u0131l\u0131k geliyor (Besinler ve hava yoluyla v\u00fccuda giren Cs 137 katk\u0131s\u0131 g\u00f6z \u00f6n\u00fcne al\u0131nmadan yap\u0131lan hesaplama).<\/p>\n

Haritada, halk\u0131n ya\u015fad\u0131\u011f\u0131, daha \u00e7ok kahverengi ve a\u00e7\u0131k maviyle g\u00f6sterilen b\u00f6lgelerde ise topraktaki Cs 137 miktar\u0131 bu de\u011ferlerin onda biriyle y\u00fczde biri aras\u0131ndaki kadar az oldu\u011fundan, oralarda ya\u015fayanlar\u0131n v\u00fccutlar\u0131na olan radyasyon etkisi de olduk\u00e7a azd\u0131r (Y\u00f6resel Cs 137 de\u011ferlerine ve oralarda kalma s\u00fcresine g\u00f6re de\u011fi\u015fim g\u00f6sterebilir).<\/p>\n

Denizdeki radyoaktivite ve insana etkisi<\/strong><\/p>\n

Fuku\u015fima Daiichi\u2019deki ilk 3 reakt\u00f6r ile 4 no\u2019lu reakt\u00f6r\u00fcn yak\u0131t elemanlar\u0131 bekletme havuzundaki so\u011futma sular\u0131, dola\u015f\u0131mdan sonra, b\u00fcy\u00fck oranda denize sal\u0131nd\u0131. \u0130lk 3 reakt\u00f6rdeki n\u00fckleer yak\u0131t ergimesi sonucu, bu sular\u0131n radyoaktivitesi \u00e7ok y\u00fcksek oldu\u011fundan, kazadan sonraki ilk aylarda deniz suyundaki I 131, Cs 134 ve Cs 137 deri\u015fimleri y\u00fcksek de\u011ferler g\u00f6sterdiler. Deniz suyundaki radyoaktivite \u00f6l\u00e7\u00fcmleri \u00f6nce k\u0131y\u0131 ile 2 km aras\u0131nda, sonra 20 ve 200 km uzakl\u0131ktaki b\u00f6lgede yap\u0131ld\u0131. Yukardaki \u00f6nemli 3 radyoizotoptan ba\u015fka, bir dizi daha a\u011f\u0131r radyoizotop deniz suyunda \u00f6l\u00e7\u00fcld\u00fcyse de, bunlar \u00e7ok d\u00fc\u015f\u00fck deri\u015fimdeydiler ve deniz \u00fcr\u00fcnleri yoluyla insana ula\u015fsalar bile v\u00fccut i\u00e7in \u00f6nemli d\u00fczeyde de\u011fildiler. K\u0131y\u0131 b\u00f6lgesinde ba\u015flang\u0131\u00e7ta \u00f6l\u00e7\u00fclen y\u00fcksek radyoaktiviteli sulardaki deniz \u00fcr\u00fcnlerinde y\u00fcksek radyoaktivite belirlendi\u011finde, bunlar\u0131n halka ula\u015fmas\u0131 \u00f6nlendi. 2013 sonunda k\u0131y\u0131 sular\u0131ndaki radyoaktivite deri\u015fimi Cs 134 ve Cs 137 i\u00e7in 1 Bq\/litre\u2019nin alt\u0131na d\u00fc\u015ft\u00fc, I 131 ise d\u00fc\u015f\u00fck yar\u0131lanma s\u00fcresi nedeniyle gitgide azalarak kendili\u011finden yok oldu.<\/p>\n

\"\"
Kapat\u0131lan\/kaps\u00fcllenen reakt\u00f6r binas\u0131.<\/figcaption><\/figure>\n

Fuku\u015fima santral alan\u0131nda so\u011futma ve temizleme \u00f6nlemleri<\/strong><\/p>\n

Bug\u00fcne kadar yap\u0131lan incelemelerden, ergiyen n\u00fckleer yak\u0131t maddesinin ilk 3 reakt\u00f6r kazan\u0131n\u0131n dibinde topland\u0131\u011f\u0131 anla\u015f\u0131l\u0131yor. 3 ve 4 numaral\u0131 reakt\u00f6rlerdeki yak\u0131t elemanlar\u0131 ile bu reakt\u00f6rlerin depolama havuzlar\u0131ndaki baz\u0131 yak\u0131t elemanlar\u0131n\u0131n bozuldu\u011fu san\u0131l\u0131yor. Reakt\u00f6rler ve bekletme havuzlar\u0131 d\u0131\u015fardan \u00f6nce deniz suyuyla sonra \u00e7evre suyuyla so\u011futuluyor. Gerek so\u011futma sular\u0131 gerekse binalar\u0131 basan tsunami sular\u0131 radyoaktif maddelerle a\u015f\u0131r\u0131 miktarda bula\u015fm\u0131\u015f oldu\u011fundan binalarda yap\u0131lmas\u0131 gereken \u00e7al\u0131\u015fmalar zorla\u015f\u0131yor ya da yap\u0131lam\u0131yor.<\/p>\n

Radyoaktif maddelerle a\u015f\u0131r\u0131 miktarda bula\u015fm\u0131\u015f sular ba\u015flang\u0131\u00e7ta denize ak\u0131t\u0131ld\u0131. Sonralar\u0131 bu sular depoland\u0131, sadece az radyoaktiviteli sular denize sal\u0131nd\u0131.<\/p>\n

Bug\u00fcne kadar yap\u0131lan \u00f6nemli \u00e7al\u0131\u015fmalar<\/strong><\/p>\n

\u0130lk 3 reakt\u00f6r i\u00e7in, hasar g\u00f6ren yak\u0131t elemanlar\u0131n\u0131n bulundu\u011fu reakt\u00f6r kazan\u0131n\u0131n i\u00e7i, 100 0<\/sup>C\u2019nin alt\u0131nda tutulacak \u015fekilde, s\u00fcrekli so\u011futuluyor. Reakt\u00f6r binalar\u0131nda toplanan radyoakiviteli su d\u0131\u015far\u0131 pompalan\u0131yor ve radyoaktif maddelerden ar\u0131nd\u0131r\u0131lmaya \u00e7al\u0131\u015f\u0131l\u0131yor.
\nReakt\u00f6rleri \u00e7al\u0131\u015ft\u0131ran TEPCO \u015firketinin yapt\u0131\u011f\u0131 plana g\u00f6re, ilk 4 reakt\u00f6r orta s\u00fcrede kontrollu bir duruma ge\u00e7irilerek hem reakt\u00f6rlerin hem de kullan\u0131lm\u0131\u015f yak\u0131t elemanlar\u0131 bekletme havuzlar\u0131ndaki yak\u0131t elemanlar\u0131n\u0131n so\u011futulmas\u0131 s\u00fcrekli sa\u011flan\u0131yor. \u00c7evreye sal\u0131nacak radyoaktif maddelerin de b\u00f6ylelikle s\u0131n\u0131rlanmas\u0131na \u00e7al\u0131\u015f\u0131l\u0131yor.
\nAyr\u0131ca hasar g\u00f6ren reakt\u00f6r binalar\u0131n\u0131n \u00fcstten ve yanlardan kapat\u0131lmas\u0131\/kaps\u00fcllenmesi yap\u0131l\u0131yor. Ba\u015flang\u0131\u00e7ta, ge\u00e7ici bir \u00e7elik iskeleye ge\u00e7irilen plastik \u00e7ad\u0131rlar, havaland\u0131rma sistemleri ve filtrelerle \u00e7evreye radyoaktif madde sal\u0131nmas\u0131 azalt\u0131ld\u0131.<\/em><\/p>\n

Reakt\u00f6r binalar\u0131n\u0131n havas\u0131ndaki radyoaktif maddeleri temizlemek i\u00e7in havaland\u0131rma sistemleri filtrelerle donat\u0131ld\u0131. Bina i\u00e7inde toz tutan yerler uzaktan komutlu aletlerle, p\u00fcsk\u00fcrtme y\u00f6ntemiyle temizleniyor. Bu \u00e7e\u015fit \u00f6nlemlerin bina i\u00e7indeki radyasyon d\u00fczeyini azalt\u0131p azaltmad\u0131\u011f\u0131 ise, binalara y\u00fcksek d\u00fczeydeki radyasyon nedeniyle girilemedi\u011finden bilinmiyor.<\/p>\n

4 no\u2019lu reakt\u00f6r binas\u0131ndaki yak\u0131t elemanlar\u0131 ve bekletme havuzundaki 1500 adet yak\u0131t eleman\u0131 \u00f6nce d\u0131\u015fardan so\u011futuldu. Havuzdaki t\u00fcm yak\u0131t elemanlar\u0131 herhangibir hasar olmadan havuzdan al\u0131nd\u0131 ve ba\u015fka bir yere aktar\u0131ld\u0131. 4 reakt\u00f6r\u00fcn de bekletme havuzlar\u0131ndaki yak\u0131t elemanlar\u0131nda korkulan ergime olmad\u0131.<\/p>\n

Reakt\u00f6rlere, saatte 4 ile 11 m3<\/sup><\/strong> aras\u0131nda so\u011futma suyu bas\u0131l\u0131yor. Reakt\u00f6r kazan silindiri i\u00e7indeki s\u0131cakl\u0131k genellikle 68 \u00b0C ile 78 \u00b0C aras\u0131nda. Kullan\u0131lm\u0131\u015f yak\u0131t elemanlar\u0131 bekletme havuzlar\u0131ndaki s\u0131cakl\u0131k ise 24 \u00b0C ile 34 \u00b0C dolay\u0131nda.<\/p>\n

Bilgisayarla yap\u0131lan benzetmelere g\u00f6re (sim\u00fclasyonlar), 1 no\u2019lu reakt\u00f6rde, n\u00fckleer yak\u0131t ergimesi kazadan 4 saat sonra; 2 ve 3 no\u2019lu reakt\u00f6rlerde ise daha da \u00f6nce olu\u015ftu\u011fu, yak\u0131t maddesinin b\u00fcy\u00fck bir b\u00f6l\u00fcm\u00fcn\u00fcn ergidi\u011fi ve reakt\u00f6r kazanlar\u0131n\u0131 delerek reakt\u00f6r binas\u0131na ula\u015ft\u0131\u011f\u0131 kestiriliyor. Reakt\u00f6r binalar\u0131n\u0131n i\u00e7ine girilemedi\u011finden ger\u00e7ek durum hen\u00fcz bilinemiyor.<\/p>\n

Reakt\u00f6rlerin \u00e7evresi ancak 30-40 y\u0131lda temizlenebilecek<\/strong><\/p>\n

\u0130lk 3 reakt\u00f6rdeki n\u00fckleer yak\u0131t maddesi ergimesinin olu\u015fturdu\u011fu hasarlarla, 1, 3 ve 4 no\u2019lu reakt\u00f6r bloklar\u0131ndaki hidrojen gaz\u0131 patlamalar\u0131n\u0131n neden oldu\u011fu hasarlar\u0131n temizlenmesinin ve santrallar\u0131n yak\u0131n \u00e7evresinin normal duruma getirilebilmesinin ancak 30-40 y\u0131lda ba\u015far\u0131labilece\u011fini TEPCO \u015eirketi a\u00e7\u0131kl\u0131yor. Patlamalar sonucu, b\u00fcy\u00fck miktarlarda radyoaktif maddelerle bula\u015fm\u0131\u015f malzeme ve par\u00e7alar santrallar\u0131n yak\u0131n \u00e7evresine f\u0131rlat\u0131lm\u0131\u015ft\u0131r. Bunlar\u0131n suyla y\u0131kan\u0131p temizlenmesi yap\u0131l\u0131yor, bunlar\u0131n radyoaktif maddelerle bula\u015fm\u0131\u015f at\u0131k sular\u0131 ise b\u00fcy\u00fck su depolar\u0131na aktar\u0131l\u0131yor. Santral alan\u0131nda bug\u00fcn bu \u00e7e\u015fit y\u00fczlerce at\u0131k su deposu bulunuyor. Bunlarda zaman zaman g\u00f6r\u00fclen ka\u00e7aklar\u0131n yeralt\u0131 suyuna ya da okyanusa ula\u015fmamas\u0131 i\u00e7in ayr\u0131ca \u00f6nlemler al\u0131nmaya \u00e7al\u0131\u015f\u0131l\u0131yor. At\u0131k sulardaki radyoaktivitenin azalt\u0131lmas\u0131 i\u00e7in temizleme sistemleri de \u00e7al\u0131\u015ft\u0131r\u0131l\u0131yor. Ancak s\u00fcregelen t\u00fcm bu \u00e7al\u0131\u015fmalar, \u00e7ok b\u00fcy\u00fck sorunlar\u0131n ancak \u00e7ok k\u00fc\u00e7\u00fck bir b\u00f6l\u00fcm\u00fcn\u00fc giderebiliyor. Radyoaktif kat\u0131 at\u0131klar ise b\u00fcy\u00fck ve kal\u0131n plastik torbalarda biriktiriliyor.<\/p>\n

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Fuku\u015fima santral alan\u0131n\u0131n bug\u00fcnk\u00fc g\u00f6r\u00fcn\u00fcm\u00fc: Alan, at\u0131k suyla dolu su tanklar\u0131na dar gelmeye ba\u015flam\u0131\u015f.<\/figcaption><\/figure>\n

Reakt\u00f6r binalar\u0131ndaki ka\u00e7ak yerlerinin kapat\u0131lmas\u0131, \u00e7evrenin, okyanusun daha fazla kirletilmemesi i\u00e7in \u00e7al\u0131\u015fmalar da s\u00fcr\u00fcyor. 2013\u2019den beri uzaktan komutlu robotlarla binalardaki ka\u00e7ak yerleri belirleniyor. \u0130lk 4 reakt\u00f6rden denize radyoaktiviteli sular\u0131n ula\u015fmas\u0131n\u0131 \u00f6nlemek amac\u0131yla TEPCO Nisan 2012\u2019de bu reakt\u00f6r binalar\u0131n\u0131n yan\u0131na su ge\u00e7irmez bir duvar\/bariyer yap\u0131m\u0131na ba\u015flad\u0131. 2014\u2019de bitirilen bu duvar ile k\u0131y\u0131daki setduvar aras\u0131ndaki alana, radyoaktif sezyumu so\u011furan\/tutan katk\u0131 maddeli toprak dolduruldu. Ayr\u0131ca radyoaktif maddelerin yeralt\u0131suyuna ve okyanusa ula\u015fmamas\u0131 i\u00e7in 2014\u2019de, ilk 4 reakt\u00f6r ile makine binalar\u0131n\u0131 boydan boya \u00e7evreleyen 2×500 m boyunda, 2x 200 m eninde ve 30m derinli\u011finde (dikd\u00f6rtgen kesilti) bir metal duvar yeralt\u0131na yerle\u015ftirildi, \u00e7ak\u0131ld\u0131. Bug\u00fcnlerde bu koruyucu \u00e7er\u00e7eve duvar\u0131n bitirilmesi bekleniyor.<\/p>\n

Radyoaktif maddelerle bula\u015fm\u0131\u015f \u00e7ok b\u00fcy\u00fck hacimdeki at\u0131k sular\u0131n, radyoaktiviteden oldu\u011funca ar\u0131nd\u0131r\u0131larak, azalt\u0131labilmesi i\u00e7in santral alan\u0131na \u00e7e\u015fitli su ar\u0131tma sistemleri kurularak, reakt\u00f6rlerden pompalanan sular ar\u0131t\u0131ld\u0131ktan sonra tekrar reakt\u00f6rlere pompalanarak, reakt\u00f6rlerin so\u011futulmas\u0131 s\u00fcrd\u00fcr\u00fcl\u00fcyor. Ar\u0131tma s\u0131ras\u0131nda \u00f6nce kirli surlardaki ya\u011flar gideriliyor, sonra da sezyumun y\u00fczde 99 oran\u0131nda azalt\u0131lmas\u0131na \u00e7al\u0131\u015f\u0131l\u0131yor. Sular tekrar reakt\u00f6rlere pompalanmadan \u00f6nce, ters ozmozla, sulardaki tuz al\u0131n\u0131yor. Bug\u00fcne kadar bu \u015fekilde ar\u0131t\u0131lan su miktar\u0131 1 milyon m3<\/sup>\u2019den de fazla. Gitgide artan su ar\u0131tma nedeniyle santral alan\u0131nda kirli su depo say\u0131s\u0131 da artmaktad\u0131r. TEPCO, santral alan\u0131na toplam 800.000 m3<\/sup> su alabilecek say\u0131da depo (su tank\u0131) yerle\u015ftirilebilece\u011fini ve buna da 2016 sonunda ula\u015f\u0131labilece\u011fini a\u00e7\u0131kl\u0131yor.<\/p>\n

Santrallar\u0131n yak\u0131n \u00e7evresi ve 20 km yar\u0131 \u00e7apl\u0131 alan radyoaktif maddelerle kirlenme durumuna g\u00f6re b\u00f6lgelere ayr\u0131lm\u0131\u015f ve ileride bunlardan baz\u0131lar\u0131n\u0131n temizlenerek oralarda daha \u00f6nce oturan halk\u0131n tekrar yerle\u015fim yerlerine d\u00f6nmeleri hedefleniyor. Bu b\u00f6lgeler Harita 2\u2019de g\u00f6steriliyor.<\/p>\n

\"\"
\u00c7izelge 2. (*) Bu s\u0131n\u0131r de\u011ferler, bebeklere mama haz\u0131rlanan su, s\u00fct, s\u00fct \u00fcr\u00fcnleri, sebze ve meyve i\u00e7indir. 8 g\u00fcnl\u00fck yar\u0131lanma s\u00fcreli I 131, 2012\u2019de bozunup kalmad\u0131\u011f\u0131ndan, sa\u011fdaki s\u00fctunda yer alm\u0131yor.<\/figcaption><\/figure>\n

Besin maddelerindeki radyaoaktivite kontrolu ve s\u0131n\u0131r de\u011ferler<\/strong><\/p>\n

Japonya Sa\u011fl\u0131k Bakanl\u0131\u011f\u0131, kazadan sonra 2011 y\u0131l\u0131 i\u00e7in, besinlerde \u00c7izelge 2\u2019nin sol s\u00fctunundaki de\u011ferleri s\u0131n\u0131r de\u011ferler olarak koymu\u015f, daha sonra 2012 y\u0131l\u0131nda bu de\u011ferleri halk\u0131n besinlere g\u00fcven duymas\u0131 i\u00e7in d\u00fc\u015f\u00fcrm\u00fc\u015ft\u00fcr (Bu de\u011ferleri a\u015fan yiyeceklerin halka ula\u015fmas\u0131n\u0131 \u00f6nleyecek \u00f6nlemlerin al\u0131nmas\u0131n\u0131 ilgili yerel yetkililerden istemi\u015ftir).(9)<\/sup><\/p>\n

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Harita 2: Fuku\u015fima santrallar\u0131 \u00e7evresinde (20 km ve \u00f6tesinde) bo\u015falt\u0131lan alanlar ve yasak
b\u00f6lge (Yay\u0131m\u0131: 30 Kas\u0131m 2012)
B\u00f6lge 1: Bo\u015faltma emirlerinin kald\u0131r\u0131lmaya haz\u0131r olu\u011fu alanlar.
B\u00f6lge 2: Buralarda oturanlar\u0131n yerle\u015fmelerine izin verilmeyen alanlar.
B\u00f6lge 3: Buralarda oturanlar\u0131n ileride tekrar yerle\u015fmelerinin g\u00fc\u00e7 g\u00f6r\u00fcnd\u00fc\u011f\u00fc yerler.
Koyu gri s\u0131n\u0131rl\u0131 alan: Yasak b\u00f6lge.
\u0130nce a\u00e7\u0131k gri s\u0131n\u0131rl\u0131 alan: Bo\u015falt\u0131labilecek b\u00f6lge, burada ya\u015fayanlardan her birinin 1 y\u0131l
sonunda 20 mSv doz alabilece\u011fi b\u00f6lge (bo\u015falt\u0131lmaya aday b\u00f6lge).<\/figcaption><\/figure>\n

Fuku\u015fima kazas\u0131 sonucu havaya sa\u00e7\u0131lan radyoaktif maddeler, ya\u011f\u0131\u015f ve kuru serpintilerle zamanla topra\u011fa ve bitkilere bula\u015fm\u0131\u015ft\u0131r. Bunlar\u0131n i\u00e7inde 8 g\u00fcnl\u00fck yar\u0131lanma s\u00fcresiyle I 131 kazadan sonraki ilk aylarda etkili olmu\u015f, Haziran 2011\u2019den sonra \u00f6nemini yitirmi\u015ftir. Daha sonraki aylarda ve y\u0131llarda 2,1 y\u0131ll\u0131k yar\u0131lanma s\u00fcresiyle Cs 134 ile 30 y\u0131ll\u0131k yar\u0131lanma s\u00fcresiyle Cs 137 etkisini s\u00fcrd\u00fcrmektedir.<\/p>\n

Ba\u015flang\u0131\u00e7ta belirlenen s\u0131n\u0131r de\u011ferler uluslararas\u0131 kurumlarca belirlenenlerle uyumlu olmas\u0131na kar\u015f\u0131n, Japon yetkili kurumunun 01.04.2012\u2019de, halk\u0131n besin maddelerine g\u00fcven duymas\u0131n\u0131 sa\u011flamak amac\u0131yla \u00e7ok d\u00fc\u015f\u00fcrd\u00fc\u011f\u00fc yeni s\u0131n\u0131r de\u011ferler (Bkz. \u00c7izelge 2\u2019deki en sa\u011f s\u00fctun) uluslararas\u0131 yetkili \u00e7evrelerce tepkiyle kar\u015f\u0131lanarak, bunlara radyasyon fizi\u011fi y\u00f6n\u00fcnden gerek olmad\u0131\u011f\u0131 bildirilmi\u015f ve bu durum tart\u0131\u015fmalara yol a\u00e7m\u0131\u015ft\u0131r. Japonya\u2019da besinlerde s\u00fcrekli \u00f6l\u00e7\u00fclen radyoaktif maddelerle ilgili ayr\u0131nt\u0131l\u0131 bilgiler, bir\u00e7ok yay\u0131nda yer almaktad\u0131r.(1, 2, 3) <\/sup>Japon h\u00fck\u00fcmet s\u00f6zc\u00fcs\u00fcn\u00fcn 17 Kas\u0131m 2011 g\u00fcn\u00fc yapt\u0131\u011f\u0131 a\u00e7\u0131klamaya g\u00f6re, ilk kez Fukushima\u2019n\u0131n Onami y\u00f6resi kaynakl\u0131 pirin\u00e7te 500 Bq\/kg\u2019l\u0131k Cs 137 s\u0131n\u0131r de\u011feri, \u00f6l\u00e7\u00fclen 630 Bq\/kg ile a\u015f\u0131lm\u0131\u015f ve bu \u00fcr\u00fcn\u00fcn halka ula\u015fmas\u0131 yasaklanm\u0131\u015ft\u0131r.<\/p>\n

Santral personelinin, Fuku\u015fima b\u00f6lgesindekilerin ve halk\u0131n ald\u0131\u011f\u0131 radyasyon dozlar\u0131<\/strong><\/p>\n

Fuku\u015fima Daiichi Santrallar\u0131n\u0131 i\u015fleten TEPCO \u015eirketinin yapt\u0131\u011f\u0131 \u00f6l\u00e7\u00fcmlere g\u00f6re Mart 2011 ile Ekim 2012 aras\u0131nda say\u0131lar\u0131 3700 ile 7600 ki\u015fi aras\u0131nda de\u011fi\u015fen personelin santrallarda yap\u0131lan \u00e7al\u0131\u015fmalarda ald\u0131klar\u0131 radyasyon dozlar\u0131 ki\u015fi ba\u015f\u0131na 1 mSv ile 200 mSv aras\u0131nda de\u011fi\u015fmektedir. Normal olarak radyasyonla \u00e7al\u0131\u015fanlar i\u00e7in y\u0131ll\u0131k doz s\u0131n\u0131r de\u011feri 20 mSv\u2019dir.<\/strong> \u00d6zel durumlarda bu de\u011fer a\u015f\u0131labiliyor ya da doz planlanmadan a\u015f\u0131lm\u0131\u015f ise ilgili ki\u015filere \u00f6zel \u00f6nlemler uygulan\u0131yor (santraldan uzakla\u015ft\u0131r\u0131lma\/izin, t\u0131bbi iyile\u015ftirme\/tedavi gibi).<\/p>\n

Yo\u011fun olarak etkilenen birinci derece \u00f6nemdeki b\u00f6lgede yeti\u015fkinler ve ilk y\u0131l i\u00e7in hesaplanan etkin doz 10 miliSievert (mSv)\u2019ten azd\u0131r. Bu dozun olu\u015fmas\u0131na en b\u00fcy\u00fck katk\u0131, hava ve yerdeki radyoaktif maddelerin insanlar\u0131 d\u0131\u015ftan \u0131\u015f\u0131nlamas\u0131ndan kaynaklan\u0131yor. V\u00fccuda hava, su ve besinler yoluyla giren radyoaktif maddelerin doza katk\u0131s\u0131 ise \u00e7ok daha az. Kazadan hemen sonra 20 km yar\u0131\u00e7apl\u0131 b\u00f6lgedeki halk\u0131n neredeyse t\u00fcm\u00fc hemen bo\u015falt\u0131l\u0131p yasak b\u00f6lge ilan edildi\u011finden (buralarda art\u0131k kimse ya\u015famad\u0131\u011f\u0131nan), doz hesaplar\u0131 Haziran 2011\u2019de bo\u015falt\u0131lan sadece k\u00fc\u00e7\u00fck bir b\u00f6lge i\u00e7in yap\u0131ld\u0131 (Hesaplar, 20 km\u2019nin d\u0131\u015f\u0131ndaki radyoaktiviteden en \u00e7ok etkilenen y\u00f6relerde, halk\u0131n kazadan sonra 4 ay buralardan ayr\u0131lmad\u0131klar\u0131 varsay\u0131larak yap\u0131ld\u0131).<\/p>\n

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\u00c7izelge 3: Fuku\u015fima kazas\u0131 sonucu al\u0131nan (beklenen) etkin radyasyon dozlar\u0131 (\u00e7izelgedeki t\u00fcm de\u011ferler: milisievert=msv)(9)
(*) Chiba, Gunma, Ibaraki, Miyagi, Tochigi ve Iwata yerle\u015fim yerleri.<\/figcaption><\/figure>\n

\u00c7izelge 3\u2019de Fuku\u015fima kazas\u0131 sonucu al\u0131nan\/beklenen \u201cradyasyon etkin dozlar\u0131\u201d ortalama de\u011ferler olarak g\u00f6steriliyor. Bu dozlar\u0131n olu\u015fmas\u0131na, ilk y\u0131lda, en b\u00fcy\u00fck katk\u0131 solunum yoluyla v\u00fccuda giren ve tiroit bezinde bir s\u00fcre yerle\u015fen radyoaktif iyottur ( I 131).<\/p>\n

\u00c7izelge 3\u2019den g\u00f6r\u00fcld\u00fc\u011f\u00fc gibi, Fuku\u015fima b\u00f6lgesinde yeti\u015fkinler i\u00e7in beklenen ya\u015fam boyu dozu 10, bebekler i\u00e7in ise 20 mSv kadard\u0131r. T\u00fcm v\u00fccut radyasyon \u00f6l\u00e7\u00fcm aletleriyle taranan 100.000\u2019den fazla ki\u015finin ilk y\u0131lda ald\u0131klar\u0131 radyasyon dozlar\u0131 \u00e7izelgedeki de\u011ferlerin alt\u0131nda kalm\u0131\u015ft\u0131r.<\/p>\n

Bug\u00fcne kadar elde edilen bilgilere dayanarak, Fuku\u015fima N\u00fckleer Santrallar\u0131nda \u00e7al\u0131\u015fan 15.000 kadar i\u015f\u00e7iden 111\u2019inin 100 miliSievert\u2019ten (mSv) daha \u00e7ok radyasyon dozu ald\u0131\u011f\u0131 belirlenmi\u015ftir. Bu doz, topluluk (kitle) \u0131\u015f\u0131nlamalar\u0131nda kanser riskini en \u00e7ok y\u00fczde 1 kadar art\u0131r\u0131yor. Kaza durumlar\u0131nda \u00e7evreyi ve halk\u0131 daha b\u00fcy\u00fck y\u0131k\u0131mlara kar\u015f\u0131 koruma \u00f6nlemlerinin al\u0131nmas\u0131n\u0131 sa\u011flamak amac\u0131yla bir i\u015f\u00e7inin alabilece\u011fi doz s\u0131n\u0131r\u0131 14 Mart 2011 g\u00fcn\u00fc 250 mSv de\u011ferine y\u00fckseltilmi\u015ftir. Bug\u00fcne kadar Fuku\u015fima\u2019da bu 250 mSv\u2019lik dozu sadece 6 radyasyon i\u015f\u00e7isi a\u015fm\u0131\u015ft\u0131r. Ki\u015fi ba\u015f\u0131na d\u00fc\u015fen radyasyon dozunu azaltmak amac\u0131yla i\u015f\u00e7i say\u0131s\u0131 art\u0131r\u0131l\u0131rken, bunlar\u0131n santrallar\u0131n y\u00fcksek radyasyonlu yerlerinde \u00e7al\u0131\u015fma s\u00fcreleri k\u0131salt\u0131lm\u0131\u015ft\u0131r. Ani radyasyon \u0131\u015f\u0131nlamalar\u0131nda deride k\u0131zarma ancak 500 mSv\u2019den daha b\u00fcy\u00fck dozlarda g\u00f6r\u00fcl\u00fcyor. \u00d6nce kayboldu\u011fu bildirilen 2 i\u015f\u00e7i sonradan (2 Nisan 2011 g\u00fcn\u00fc) \u00f6l\u00fc olarak bulunmu\u015ftur. Ancak bu iki i\u015f\u00e7inin radyasyon dozu sonucu de\u011fil, su bask\u0131n\u0131nda \u00f6ld\u00fc\u011f\u00fc belirlenmi\u015ftir.<\/p>\n

\u00c7evrenin radyoaktif maddelerle bula\u015fmas\u0131ndan ve buralarda yeti\u015fecek sebze, meyve ve bal\u0131klar\u0131n halka kontrollu ula\u015fmas\u0131 sonucu, bunlar\u0131n ancak d\u00fc\u015f\u00fck radyoaktivitedeyse yenmesinden olu\u015facak d\u00fc\u015f\u00fck d\u00fczeydeki ek radyasyon dozunun, ilerde de genellikle halk\u0131n s\u00fcrekli etkilenmekte oldu\u011fu do\u011fal radyasyon dozlar\u0131n\u0131n ve \u00fclkelerin s\u0131n\u0131r de\u011ferlerinin alt\u0131nda kalmas\u0131 bekleniyor. Buna ra\u011fmen yukarda a\u00e7\u0131kland\u0131\u011f\u0131 gibi Japonya\u2019da seyrek de olsa baz\u0131 besinlerde (\u00f6zellikle bal\u0131k ve mantarlarda) daha y\u00fcksek d\u00fczeyde radyoaktivite (\u00f6zellikle sezyum radyoaktivitesi) g\u00f6r\u00fclebilece\u011finden besinlerde yap\u0131lmakta olan radyoaktivite \u00f6l\u00e7\u00fcmleri ve kontrollar uzun s\u00fcre devam edecektir.<\/p>\n

Bulgular ve \u00f6zetle bug\u00fcnk\u00fc durum <\/strong><\/p>\n

– Fuku\u015fima b\u00f6lgesinde Cs 134 ve Cs 137 en yo\u011fun radyoizotoplar olmu\u015ftur.<\/p>\n

– V\u00fccudun d\u0131\u015ftan \u0131\u015f\u0131nlanmas\u0131, radyasyon dozunun olu\u015fmas\u0131na en b\u00fcy\u00fck katk\u0131y\u0131 sa\u011flam\u0131\u015ft\u0131r.<\/p>\n

– V\u00fccudun i\u00e7ten \u0131\u015f\u0131nlanmas\u0131, s\u0131k\u0131 besin kontrollar\u0131 nedeniyle \u00f6nemsiz kalm\u0131\u015ft\u0131r.<\/p>\n

– Japonya\u2019n\u0131n her yerinde Fuku\u015fima kaynakl\u0131 radyoizotoplar \u00f6l\u00e7\u00fclm\u00fc\u015f ise de, Fuku\u015fima b\u00f6lgesi en \u00e7ok etkilenen b\u00f6lge olmu\u015ftur.<\/p>\n

– En \u00e7ok radyoizotop birikmesi, n\u00fckleer reakt\u00f6rlerin kuzeybat\u0131 y\u00f6resinde g\u00f6r\u00fclm\u00fc\u015ft\u00fcr.<\/p>\n

– Uluslararas\u0131 ara\u015ft\u0131rmalar (WHO, UNSCEAR) ve santral alan\u0131n\u0131n temizlenmesi, reakt\u00f6rlerin so\u011futulmas\u0131, binalar\u0131n \u00e7evresine set \u00e7ekilmesi, havaland\u0131rma, filtreleme ve yak\u0131n \u00e7evrede koruyucu \u00f6nlemler al\u0131nmas\u0131 gibi daha bir dizi \u00f6nlem, onar\u0131m, bak\u0131m ve ar\u0131nd\u0131rma \u00e7al\u0131\u015fmalar\u0131 s\u00fcrmektedir.<\/p>\n

Fuku\u015fima \u00e7evresinde radyasyona ba\u011flanabilecek bir \u00f6l\u00fcm bug\u00fcne kadar belirlenememi\u015f ise de kazan\u0131n buralarda ya\u015fayanlara en olumsuz etkisi, radyoaktif (Cs 134, Cs 137) maddelerin her yeri kirletmi\u015f olmas\u0131 sonucu, b\u00f6lgenin b\u00fcy\u00fck bir b\u00f6l\u00fcm\u00fcnde daha uzun y\u0131llar oturulamayaca\u011f\u0131, tar\u0131m yap\u0131lamayaca\u011f\u0131, end\u00fcstri kurulamayaca\u011f\u0131 ger\u00e7e\u011fidir. Radyoaktif maddelerin az bula\u015fm\u0131\u015f oldu\u011fu y\u00f6relerde ise, bunlar\u0131n topraktan ar\u0131nd\u0131r\u0131lmas\u0131 i\u00e7in \u00e7ok \u00e7e\u015fitli yol ve y\u00f6ntemler denenmektedir. Ama\u00e7 buralarda daha \u00f6nce oturanlar\u0131 tekrar buraya yerle\u015ftirebilmektir. Bunun i\u00e7in hedef, buraya yerle\u015fecek bir ki\u015fide ileride olu\u015fabilecek radyasyon dozunun y\u0131lda 1 mSv\u2019in alt\u0131nda kalmas\u0131d\u0131r. Sezyumun topraktan ar\u0131nd\u0131r\u0131lmas\u0131 i\u00e7in ABD\u2019den, Phytotech, Inc \u015eirketinin 1996\u2019da bulup \u00c7ernobil yak\u0131nlar\u0131nda uygulad\u0131\u011f\u0131 \u201ctopra\u011fa Helianthus<\/em> sp. cinsi ay\u00e7i\u00e7e\u011fi ekme\u201d y\u00f6ntemini Japon ara\u015ft\u0131rmac\u0131lar kendileri bulmu\u015flar gibi Fuku\u015fima sonras\u0131 haber yapm\u0131\u015flard\u0131r. Bu transgen lifli ay\u00e7i\u00e7e\u011finin 24 saatte topraktaki sezyumun y\u00fczde 95\u2019ini emdi\u011fini ABD\u2019li ara\u015ft\u0131rmac\u0131lar 1996\u2019da a\u00e7\u0131klam\u0131\u015ft\u0131r. Toprakta potasyumlu g\u00fcbre kullan\u0131lmad\u0131\u011f\u0131nda, ay\u00e7i\u00e7e\u011fi bitkisinin topraktaki sezyumu potasyum yerine liflerine \u00e7ekti\u011fi belirlenmi\u015ftir. Bu ve di\u011fer y\u00f6ntemlerin Fuku\u015fima\u2019da ileride ne \u00f6l\u00e7\u00fcde uygulanabilece\u011fini, halk\u0131n ne kadar\u0131n\u0131n evlerine d\u00f6nebilece\u011fini ise zaman g\u00f6sterecektir. Radyoaktif sezyumun az bula\u015ft\u0131\u011f\u0131 b\u00f6lgelerin temizlenerek 25.000 ki\u015finin ilk planda buralara d\u00f6nebilece\u011fi bekleniyor.<\/p>\n

Kanser riski<\/strong><\/p>\n

D\u00fcnya Sa\u011fl\u0131k \u00d6rg\u00fct\u00fc\u2019n\u00fcn (WHO) 28 \u015eubat 2013 g\u00fcn\u00fc Cenevre\u2019de sundu\u011fu bilimsel raporda(6)<\/sup>, kanser riskinin, santral\u0131n 20-30 km \u00e7evresi d\u0131\u015f\u0131nda \u00e7ok az artt\u0131\u011f\u0131 a\u00e7\u0131klan\u0131yor. Uzmanlar, buna ra\u011fmen, buralarda ya\u015fayanlar\u0131n, uzun s\u00fcre g\u00f6zlem alt\u0131nda bulundurulmas\u0131n\u0131 \u00f6neriyor. Ara\u015ft\u0131rmada, sa\u011fl\u0131k riskinin Japonya i\u00e7inde de, d\u0131\u015f\u0131nda da d\u00fc\u015f\u00fck oldu\u011fu belirtiliyor. Kanser hastal\u0131klar\u0131n\u0131n b\u00fcy\u00fck oranda artaca\u011f\u0131 beklenmiyor. Buna ra\u011fmen, baz\u0131 kanser t\u00fcrleri ve Fuku\u015fima \u00e7evresindeki 1-2 yerle\u015fim yerindekiler i\u00e7in riskin artt\u0131\u011f\u0131 ileri s\u00fcr\u00fclerek, buralarda ya\u015fayanlar\u0131n uzun s\u00fcre g\u00f6zlem alt\u0131nda bulundurulmas\u0131 gerekti\u011fi vurgulan\u0131yor. Bu raporu, radyasyon fizi\u011fi, risk modelleme, epidemiyoloji, radyoaktivite \u00f6l\u00e7\u00fcm tekni\u011fi, radyasyon kazalar\u0131 ve halk sa\u011fl\u0131\u011f\u0131 dallar\u0131nda bilimsel ara\u015ft\u0131rmalar yapan 30 kadar ba\u011f\u0131ms\u0131z uzman birlikte \u00e7al\u0131\u015farak haz\u0131rlad\u0131lar. Bu raporun \u00f6nemli sonu\u00e7lar\u0131:<\/p>\n

– Fuku\u015fima \u00e7evresinde radyoaktif maddelerle daha az bula\u015fm\u0131\u015f ikinci derece \u00f6nemdeki b\u00f6lgelerde ya\u015fayanlar\u0131n kansere yakalanma riskleri a\u015f\u0131r\u0131 kirlenen b\u00f6lgelerdeki risklerin yar\u0131s\u0131 kadard\u0131r.<\/p>\n

– <\/em>Fuku\u015fima Santrallar\u0131nda g\u00f6rev yapan kurtarma ekiplerinde \u00e7al\u0131\u015fanlar\u0131n \u00fc\u00e7te ikisinin kansere yakalanma riskinin, t\u00fcm toplumun ald\u0131\u011f\u0131 risk kadar oldu\u011fu kestirilmektedir. Sadece \u00fc\u00e7te birinin kanser riski daha y\u00fcksektir.<\/p>\n

– <\/em>Fuku\u015fima kazas\u0131 sonucu \u00e7evrede ya\u015fayanlar\u0131n v\u00fccutlar\u0131nda olu\u015fan radyasyon dozlar\u0131n\u0131n, \u00f6z\u00fcrl\u00fc ve \u00f6l\u00fc do\u011fumlara neden olmayaca\u011f\u0131, kazadan sonra do\u011fanlarda ileride fiziksel, duygusal (ruhsal) bozukluklar g\u00f6r\u00fclmeyece\u011fi belirtiliyor.<\/p>\n

– <\/em>Fuku\u015fima kazas\u0131n\u0131n psikososyal etkileri, insan sa\u011fl\u0131\u011f\u0131 ve mutlulu\u011funu bozabilece\u011finden bu konunun s\u00fcrekli izlenmesi ve incelenmesi gerekti\u011fini uzmanlar \u00f6nermektedir.<\/p>\n

Bu raporda, y\u00fcksek risk ta\u015f\u0131yan insanlar\u0131n s\u00fcrekli t\u0131p kontrolunda bulundurulmalar\u0131 ve bunun koruyucu halk sa\u011fl\u0131\u011f\u0131 \u00e7er\u00e7evesinde, Japonya sa\u011fl\u0131k kurumlar\u0131n\u0131n \u00f6nemli bir g\u00f6revi olmas\u0131 gerekti\u011fi a\u00e7\u0131klan\u0131yor. T\u0131p kontrollar\u0131 ve ara\u015ft\u0131rmalar\u0131n\u0131n yan\u0131 s\u0131ra, radyoaktif maddelerle bula\u015fan \u00e7evrenin, \u00f6zellikle besinlerin, sular\u0131n s\u00fcrekli kontrolu ve al\u0131nacak koruyucu \u00f6nlemlerle ileride halk\u0131n radyasyon dozlar\u0131n\u0131n azalt\u0131labilece\u011fi de raporda vurgulan\u0131yor.<\/p>\n

N\u00fckleer santrallar\u0131n 20-30 km \u00e7evresindeki radyoaktif maddelerden a\u015f\u0131r\u0131 \u00f6l\u00e7\u00fcde etkilenmi\u015f birinci derece \u00f6nemdeki b\u00f6lgede (Bkz. Harita 2\u2019de, \u00f6zellikle Iiate ve Namie yerle\u015fim yerlerinde) ya\u015fayanlar ve t\u00fcm\u00f6r cinsleri i\u00e7in, uzmanlar, her bir kanser cinsiyle ilgili toplumda zaten g\u00f6r\u00fclen riskin, Fuku\u015fima kazas\u0131 sonucu, \u00e7ocukken radyasyondan etkilenen kad\u0131nlarda kat\u0131 (solid) t\u00fcm\u00f6rlerin y\u00fczde 4, kan kanseri (l\u00f6semi) y\u00fczde 7, kad\u0131nlarda g\u00f6\u011f\u00fcs (meme) kanserinin y\u00fczde 6 kadar artabilece\u011fini hesapl\u0131yorlar.<\/p>\n

D\u00fcnya\u2019da \u00f6lenlerin ortalama olarak d\u00f6rtte biri kanserden \u00f6l\u00fcyor: Kanser riski: y\u00fczde 25.<\/p>\n

Bir toplulukta her ki\u015fi 1 Sv\u2019lik etkin bir radyasyon dozu ald\u0131\u011f\u0131nda kanser riski: y\u00fczde 5.<\/p>\n

Fuku\u015fima b\u00f6lgesinde her ki\u015fi en \u00e7ok 20 mSv\u2019lik etkin bir radyasyon dozu ald\u0131\u011f\u0131nda kanser riski: y\u00fczde 5 x 20\/1000=0,001.<\/p>\n

1000 ki\u015fiden her biri 20 mSv\u2019lik doz ald\u0131\u011f\u0131nda bunlardan 1 ki\u015fi kansere yakalan\u0131p \u00f6lebiliyor. Ama toplumda bu 1000 ki\u015fiden 250\u2019si zaten di\u011fer etkenlerle olu\u015fan kanser sonucu \u00f6ld\u00fc\u011f\u00fcnden bu 1 ki\u015finin kan\u0131tlanmas\u0131 olanaks\u0131z.<\/p>\n

\u00d6te yandan her g\u00fcn 1 \u015fi\u015fe bira ya da 1-2 bardak \u015farap i\u00e7ildi\u011finde kanser riski y\u00fczde 2 = 0,02<\/p>\n

Alkol riski \/ Fuku\u015fima riski= 0,02\/0,001= 20 kat daha \u00e7ok.<\/p>\n

Ya da Fuku\u015fima\u2019dakilerin ald\u0131klar\u0131 dozun riski, g\u00fcnde 1 \u015fi\u015fe biran\u0131n 20\u2019de birini i\u00e7mekle ya da i\u00e7inde 1-2 gram alkol bulunan bir pralin yemekle ayn\u0131.<\/p>\n

\"\"
\u00c7izelge 4: Kanser risklerinin kar\u015f\u0131la\u015ft\u0131r\u0131lmas\u0131.<\/figcaption><\/figure>\n

Psikolojik ve sosyal etkiler<\/strong><\/p>\n

Bug\u00fcne kadar elde edilen bulgulara g\u00f6re, Japonya\u2019n\u0131n kuzeydo\u011fu b\u00f6lgesinde ya\u015fayan ve radyasyon ve radyoaktivite konular\u0131na yabanc\u0131 olan halkta, kazan\u0131n radyasyon etkilerinden \u00e7ok, depresyon gibi psikolojik (ruhsal, zihinsel, travmatik, \u00e7\u00f6k\u00fcnt\u00fc) etkilerinin daha a\u011f\u0131r basarak sosyal sorunlar yaratt\u0131\u011f\u0131 ya da yaratabilece\u011fi de a\u00e7\u0131klan\u0131yor. Bunlar\u0131n, halk sa\u011fl\u0131\u011f\u0131na ve i\u015f ya\u015fam\u0131na, radyasyon etkileri kadar zararl\u0131 olabilece\u011fi vurgulan\u0131yor. Japon medyas\u0131nda, radyasyon etkisiyle yak\u0131nda kansere yakalan\u0131p \u00f6lece\u011fini d\u00fc\u015f\u00fcnen, depresyon ve travma ge\u00e7irerek hastalanan, \u00f6len ve hatta ya\u015fam\u0131na son verenlerin say\u0131s\u0131n\u0131n 1000 ki\u015fiyi ge\u00e7ti\u011fi yer al\u0131yor ama bunlar kan\u0131tlanm\u0131\u015f de\u011fil. Buna ra\u011fmen, gelecekte yetkili kurumlar\u0131n, elde edilen bulgular\u0131, konuya yabanc\u0131 olanlar\u0131n da anlayabilece\u011fi \u015fekilde a\u00e7\u0131klamalar\u0131, radyasyon ve radyoaktiviteyle ilgili temel bilgileri, topluma, daha s\u0131k ve kapsaml\u0131 olarak aktarmalar\u0131 \u00f6neriliyor.<\/p>\n

N\u00fckleer santral kazalar\u0131 sonras\u0131nda ortaya \u00e7\u0131kabilecek bu \u00e7e\u015fit psikolojik, travmatik ve sosyal sorunlarla ilgili olarak nelerin yap\u0131labilece\u011fi konusunda bug\u00fcne kadar bir plan, program ve yapt\u0131r\u0131mlar bulunmad\u0131\u011f\u0131ndan, ara\u015ft\u0131rmac\u0131lar, bunlar\u0131n bir an \u00f6nce yap\u0131lmas\u0131n\u0131n \u00f6nemini vurguluyorlar.<\/p>\n

Fuku\u015fima n\u00fckleer kazas\u0131ndan yeni yap\u0131lacak n\u00fckleer santrallar i\u00e7in al\u0131nabilecek dersler<\/strong><\/p>\n

1970\u2019li y\u0131llar\u0131n eskimi\u015f teknolojisiyle kurulup \u00e7al\u0131\u015ft\u0131r\u0131lan Fuku\u015fima reakt\u00f6rlerinde Mart 2011\u2019deki kazalara yol a\u00e7an n\u00fckleer ve radyasyon g\u00fcvenli\u011fiyle ilgili teknik donan\u0131m ve di\u011fer eksiklikler, yeni n\u00fckleer santral yap\u0131m\u0131nda g\u00f6z \u00f6n\u00fcne al\u0131n\u0131p giderildi\u011finde, benzer b\u00fcy\u00fck kazalar \u00f6nlenebilir.<\/p>\n

Yeni bir n\u00fckleer santral projesi i\u00e7in, Fuku\u015fima kazas\u0131ndan al\u0131nacak \u00f6nemli derslerin ba\u015fl\u0131calar\u0131 \u015funlar olabilir:<\/p>\n

1) Santral depreme daha dayan\u0131kl\u0131 olarak projelendirilip kurulmal\u0131,<\/p>\n

2) Santrala verilen elektri\u011fin kesilmesinde, ivedi (acil) dizel jenerat\u00f6rleri sorunsuz \u00e7al\u0131\u015facak \u015fekilde projelendirilmeli ve \u00fcst katlara konu\u015fland\u0131r\u0131lmal\u0131,<\/p>\n

3) Hidrojen gaz\u0131 olu\u015fmas\u0131n\u0131 \u00f6nleyecek sistem projede bulunmal\u0131, ileride kurulup \u00e7al\u0131\u015ft\u0131r\u0131larak patlamalar ortaya \u00e7\u0131kmamal\u0131,<\/p>\n

4) N\u00fckleer yak\u0131t maddesinin ergimesi (erimesi) durumunda, reakt\u00f6r kazan\u0131 d\u0131\u015ftan so\u011futularak \u00e7eli\u011fin yap\u0131s\u0131 (sertli\u011fi) bozulmadan ergiyen yak\u0131t, kazan i\u00e7inde kalmal\u0131, kazan delinmemeli,<\/p>\n

5) Buna ra\u011fmen, \u00e7ok y\u00fcksek s\u0131cakl\u0131kta reakt\u00f6r kazan\u0131n\u0131n delinmesi durumunda, kazan\u0131n alt\u0131nda yak\u0131t tutma \u00e7ana\u011f\u0131 bulunmal\u0131,<\/p>\n

6) B\u00fcy\u00fck bir kaza durumu i\u00e7in santralda ivedi (acil) \u201cteknik komuta merkezi\u201d bulunmal\u0131, personel belirli aral\u0131klarda yap\u0131lan al\u0131\u015ft\u0131rmalarla e\u011fitilmeli, deneyim kazanmal\u0131,<\/p>\n

7) Projede sim\u00fclat\u00f6r bulunmal\u0131, personel reakt\u00f6r ve yard\u0131mc\u0131 sistemlerin \u00e7al\u0131\u015ft\u0131r\u0131lmas\u0131nda deneyim kazanmal\u0131.<\/p>\n

Fuku\u015fima kazas\u0131ndan elde edilen bu derslerin, Akkuyu ve Sinop\u2019ta kurulmas\u0131 planlanan n\u00fckleer santral projelerine aktar\u0131lmas\u0131, radyasyon g\u00fcvenli\u011fi en y\u00fcksek n\u00fckleer santrallar\u0131n T\u00fcrkiye\u2019de kurulabilmesine b\u00fcy\u00fck katk\u0131 sa\u011flayacakt\u0131r.(7, 8)<\/sup><\/p>\n

Konuya yabanc\u0131 olanlar i\u00e7in radyasyon birim ve kavramlar\u0131<\/strong><\/p>\n

Radyoaktivite birimi – 1 Becquerel (Bq):<\/strong> Saniyede 1 bozunma ya da par\u00e7alanma g\u00f6steren radyoaktif madde miktar\u0131d\u0131r. Eski birim Curie\u2019yle kar\u015f\u0131la\u015ft\u0131r\u0131ld\u0131\u011f\u0131nda \u00e7ok k\u00fc\u00e7\u00fckt\u00fcr: 1 Curie= 3,7 x 1010<\/sup> Bq. N\u00fckleer santrallardaki \u00f6rne\u011fin bir su s\u0131z\u0131nt\u0131s\u0131ndaki suda b\u00fcy\u00fck Bq say\u0131lar\u0131yla verilen, az miktardaki bir radyoaktivite deri\u015fimi bile, Bq say\u0131s\u0131 b\u00fcy\u00fck oldu\u011fundan halk aras\u0131nda radyoaktivitenin ve tehlikenin \u00e7ok b\u00fcy\u00fck oldu\u011fu izlenimini yaratabiliyor. Asl\u0131nda sadece Bq say\u0131s\u0131yla verilen radyoaktivitenin insana etki y\u00f6n\u00fcnden bir anlam\u0131 bulunmuyor. Bq say\u0131s\u0131n\u0131n yan\u0131 s\u0131ra bunun, hangi cins radyoizotoptan kaynakland\u0131\u011f\u0131 ve o su s\u0131z\u0131nt\u0131s\u0131n\u0131n yak\u0131n\u0131nda kimsenin uzun s\u00fcre kal\u0131p kalmad\u0131\u011f\u0131, ya da su s\u0131z\u0131nt\u0131s\u0131n\u0131n topra\u011fa, sulara ve bunlardan da herhangi bir yolla insana besinler ya da hava yoluyla ula\u015f\u0131p ula\u015fmad\u0131\u011f\u0131n\u0131n bilinmesi gerekiyor. Herhangi bir radyoizotopun atom \u00e7ekirde\u011fi bozundu\u011funda\/par\u00e7aland\u0131\u011f\u0131nda o atom \u00e7ekirde\u011fine \u00f6zg\u00fc enerjilerde bir ya da birka\u00e7 hatta bir dizi \u0131\u015f\u0131n sal\u0131n\u0131yor (alfa, beta ve gama \u0131\u015f\u0131nlar\u0131, \u00f6rne\u011fin I 131, 3 farkl\u0131 enerjide gama \u0131\u015f\u0131n\u0131 sal\u0131yor). Atom \u00e7ekirdeklerinden sal\u0131nan bu \u00e7e\u015fit \u0131\u015f\u0131nlar\u0131n enerjilerine ve insan\u0131 d\u0131\u015ftan ya da i\u00e7ten (solunum ve sindirim yoluyla v\u00fccuda girerek) \u0131\u015f\u0131nlama durumlar\u0131na g\u00f6re, v\u00fccutta olu\u015fan radyasyon dozu ve etki de farkl\u0131 oluyor. Bu nedenle sadece Bq say\u0131lar\u0131n\u0131 bilmenin bir yarar\u0131 olmuyor.<\/p>\n

\"\"<\/p>\n

\u00d6te yandan v\u00fccudumuza besinler ve i\u00e7me suyu yoluyla do\u011fadaki radyoaktif maddeler az da olsa girip yerle\u015fiyor. Bunlardan en \u00f6nemlileri 70 kg\u2019l\u0131k bir insan v\u00fccudunda ortalama olarak : K 40: 4500 Bq, C 14: 3800 Bq, Rb 87: 650 Bq, Pb 210, Bi 210 ve Po 210: 60 Bq, Rn 220+ Rn 222 bozunma \u00fcr\u00fcnleri: 30+15 Bq, H 3: 25 Bq , Be 7: 25 Bq ve ba\u015fkalar\u0131.<\/p>\n

V\u00fccudumuzdaki bu radyoaktif maddelerden, v\u00fccudumuz az da olsa \u0131\u015f\u0131n sa\u00e7\u0131yor. Sevgiden sar\u0131ld\u0131klar\u0131m\u0131z\u0131 \u0131\u015f\u0131nlad\u0131\u011f\u0131m\u0131z\u0131n fark\u0131nda de\u011filiz!<\/p>\n

Atom \u00e7ekirdeklerinin bozunmas\u0131 \/ par\u00e7alanmas\u0131 s\u0131ras\u0131nda yay\u0131nlanan alfa, beta ve gama \u0131\u015f\u0131nlar\u0131 \u015eekil 1\u2019de g\u00f6steriliyor. En sa\u011fda, gama \u0131\u015f\u0131nlar\u0131n\u0131n ba\u015fka bir atomla etkile\u015fmesi ve ondan bir d\u0131\u015f elektron s\u00f6kerek bir iyon \u00e7ifti olu\u015fturmas\u0131 g\u00f6steriliyor (\u00f6rne\u011fin h\u00fccre i\u00e7inde).<\/p>\n

\"\"Radyasyon dozu birimi-1 Sievert (Sv):<\/strong> V\u00fccudun so\u011furdu\u011fu radyasyon dozu i\u00e7in kullan\u0131lan birim. 1 Sievert, gama ve beta \u0131\u015f\u0131nlar\u0131 i\u00e7in, v\u00fccudun kilogram\u0131 ba\u015f\u0131na 1 Joule\u2019luk enerji so\u011furumuna e\u015fde\u011ferdir. Asl\u0131nda \u00f6rne\u011fin 100 graml\u0131k bir paketi 1 m yukar\u0131 kald\u0131rmak i\u00e7in gereken enerjiye e\u015fde\u011fer olan 1 Joule\u2019l\u00fck enerji, g\u00fcnl\u00fck ya\u015famda \u00e7ok k\u00fc\u00e7\u00fck bir birimdir. Bu miktar enerji radyoaktif maddelerden yay\u0131nlanan \u0131\u015f\u0131nlarla h\u00fccrelere aktar\u0131ld\u0131\u011f\u0131nda ise h\u00fccrenin i\u015flevi, yap\u0131s\u0131 bozuldu\u011fundan, insana etkisi \u00e7ok b\u00fcy\u00fck olup, bu nedenle, Sievert\u2019in binde biri olan miliSv (mSv) ve milyonda birimi olan mikroSv (\u00b5Sv) kullan\u0131l\u0131yor.(7)<\/sup><\/p>\n

I 131, Cs134 ve Cs 137 radyoizotoplar\u0131ndan her birinden 1 Bq\u2019lik radyoaktivite v\u00fccuda girdi\u011finde, bunlar\u0131n v\u00fccutta olu\u015fturabilece\u011fi radyasyon dozlar\u0131, \u00c7izelge 5\u2019de mikroSv (\u00b5Sv) olarak g\u00f6steriliyor. Bunlara besinler ve i\u00e7me suyu yoluyla al\u0131nan radyoaktif maddeler i\u00e7in sindirim doz katsay\u0131lar\u0131 deniyor (\u00b5Sv\/Bq).<\/p>\n

\"\"
\u00c7izelge 5.<\/figcaption><\/figure>\n

Ayn\u0131 radyoaktivitedeki (burada 1 Bq) farkl\u0131 radyoaktif\u00a0 maddelerin v\u00fccutta olu\u015fturdu\u011fu radyasyon dozlar\u0131n\u0131n farkl\u0131 oldu\u011fu \u00c7izelge 5\u2019den de g\u00f6r\u00fcl\u00fcyor. Yukar\u0131da belirtildi\u011fi gibi, bu nedenle radyoaktif maddenin cinsi bilinmeden sadece Bq say\u0131lar\u0131n\u0131n bir anlam\u0131 bulunmuyor.<\/p>\n

Ayr\u0131ca v\u00fccuda al\u0131nan kimyasal maddelerin, v\u00fccuttan normal yollarla at\u0131lmas\u0131 da \u00f6nemli. Bununla ilgili biyolojik yar\u0131lanma s\u00fcreleri, fiziksel yar\u0131lanma s\u00fcrelerinden farkl\u0131d\u0131r. Biyolojik yar\u0131lanma s\u00fcresi, v\u00fccuda al\u0131nan bir maddenin yar\u0131s\u0131n\u0131n v\u00fccuttan at\u0131lana kadar ge\u00e7en s\u00fcre olup, iyot i\u00e7in 40 ile 140 g\u00fcn aras\u0131nda de\u011fi\u015fim g\u00f6sterirken, sezyum i\u00e7in 70 g\u00fcn (t\u00fcm v\u00fccut) ve kaslar i\u00e7in de 140 g\u00fcnd\u00fcr.(7)<\/sup><\/p><\/blockquote>\n

Kaynaklar<\/strong><\/p>\n

1) http:\/\/www.unscear.org\/unscear\/en\/fukushima.html<\/p>\n

2) Uluslararas\u0131 Atom Enerjisi Yay\u0131nlar\u0131 (IAEA)\u201a Fukushima Status Report<\/em>, 10 Kas\u0131m 2011.<\/p>\n

3) https:\/\/www.iaea.org\/newscenter\/news\/fukushima-nuclear-accident-update-log-51<\/p>\n

4) Stohl, A. ve ark., \u201cAtoms. Chem. Phys. Discuss\u201d, 11, 28319\u201328394, 2011.
\n\u201c Xenon-133 and caesium-137 releases into the atmosphere from the Fukushima Daiichi nuclear power plant: determination of the source term, atmospheric dispersion and deposition.\u201d<\/p>\n

5) Almanya Radyasyondan Korunma Kurulu\u2019nun (Bundesamt f\u00fcr Strahlenschutz) raporlar\u0131.<\/p>\n

6) WHO Report, Feb. 2013; \u201cHealth risk assessment from the Fukushima nuclear accident\u201d, 2011.<\/p>\n

7) Y.Atakan, Radyasyon ve Sa\u011fl\u0131\u011f\u0131m\u0131z?<\/em>, Nobel Yay\u0131nlar\u0131, 2014.<\/p>\n

8) Y. Atakan, \u00dclkemizde kurulacak n\u00fckleer santrallar\u0131n radyasyon g\u00fcvenli\u011fiyle ilgili \u00f6neriler<\/em>, Fizik M\u00fchendisleri Odas\u0131 Yay\u0131nlar\u0131, Ocak 2015<\/p>\n

9) Strahlenschutz Praxis, Heft 1, 2015, Fachverband Strahlenschutz<\/p>\n

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

D\u00fcnya Sa\u011fl\u0131k \u00d6rg\u00fct\u00fc\u2019n\u00fcn Cenevre\u2019de sundu\u011fu, 30 kadar ba\u011f\u0131ms\u0131z uzman taraf\u0131ndan haz\u0131rlanan bilimsel raporda, kanser riskinin, Fuki\u015fima Santral\u0131n\u0131n 20-30 km \u00e7evresi d\u0131\u015f\u0131nda \u00e7ok az artt\u0131\u011f\u0131 a\u00e7\u0131klan\u0131yor. Uzmanlar, buna ra\u011fmen, buralarda ya\u015fayanlar\u0131n, uzun s\u00fcre g\u00f6zlem alt\u0131nda bulundurulmas\u0131n\u0131 \u00f6neriyor. Kanser hastal\u0131klar\u0131n\u0131n b\u00fcy\u00fck oranda artaca\u011f\u0131 beklenmese de, baz\u0131 kanser t\u00fcrleri ve Fuku\u015fima \u00e7evresindeki 1-2 yerle\u015fim yerindekiler i\u00e7in riskin artt\u0131\u011f\u0131 […]<\/p>\n","protected":false},"author":560,"featured_media":21861,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[171,217,232],"tags":[691,742,693,692],"class_list":["post-21860","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-134-sayi","category-cevre-bilimleri","category-yerbilimleri","tag-deprem","tag-fukusima","tag-japonya","tag-tsunami"],"acf":[],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t