Kun-Woo Cho ICRP C4 Member & UNSCEAR National Representative

Transcription

1 The 7 th Asian Regional Conference on the Evolution of the System of Radiological Protection Organized by OECD/NEA CRPPH 8 January 2015 Kun-Woo Cho ICRP C4 Member & UNSCEAR National Representative kwcho@kins.re.kr Korea Institute of Nuclear Safety

2 Contents I II III IV V VI Characterization of Fukushima Disaster Response to Fukushima Disaster by Korean Government Understanding of Fukushima Disaster by Korean Public Radiological Protection Issues in Korea: Practices Radiological Protection Issues in Korea: Principles Conclusion 2

3 Charaterization of Fukushima Disaster

4 FDNPS Accident ( )

5 Protective action areas Lifting Evacuation-Prepared Area September 30 April 22 April 22 Deliberate Evacuation Area March 12 April 22 Sheltering Area March 15 Lifting September 30 Evacuation Area 警 Restricted 戒区域 Area Fukushima Dai-ich NPP Evacuation-Prepared Area April 22 Sheltering 屋内退避区域 Area March 15 Fukushima Dai-ni NPP Assign some Specific Spots Recommended for Evacuation on June 16 Courtesy of Mr. Toshimitsu Homma, ICRP C4 5

6 Chernobyl vs Fukushima Area Estimates of the total release (PBq) 131 I 137 Cs 133 Xe 132 Te 140 Ba, 140 La Chernobyl 1, ,500 1, Fukushima 100 ~ 500 1) 6 ~ 40 2) 10, ~ 20% of Chernobyl atmospheric releases 1) about 2 ~ 8% of the total inventory of 131I in the three operating reactors (Units 1 3) at the time of the accident. 2) about 1 ~ 6% of the total inventory of 137Cs in the three operating reactors (Units 1 3) at the time of the accident. Refs: UNSCEAR 2014 Report Annex A Levels and effects of radiation exposure due to the Fukushima nuclear accident 6

7 Cs-137 deposition density at Fukushima and Chernobyl 200km Same Scale Courtesy of Mr. Toshimitsu Homma, ICRP C4 7

8 Transport and Dispersion in the Ocean Long-term global transport Ref. : UNSCEAR Fukushima Report Expert Group A Technical Advisor M. Nakano research paper 4 5 years later, reach the US Californian coast 137 Cs : < 3 mbq/l 20 years later, all Pacific ocean 137 Cs : < 0.3 mbq/l non-detectable level 30 years later, to Indian ocean 137 Cs : < 0.1 mbq/l non-detectable level Avg. 137 Cs concentration in Pacific ocean: 2.6 mbq/l (IAEA-TECDOC-1429 ) Ref. : UNSCEAR Report (2014), Levels and effects of radiation exposure due to the nuclear accident after the 2011 great east japan earthquake and tsunami, Appendix B, para. B82, p.122; M. Nakano and P.P. Povinec, Long-term simulation of the 137Cs dispersion from the Fukushima accident in the world ocean, J. Environmental Radioactivity 111: pp (2012) 8

9 Response to Fukushima Disaster by Korean Government

10 03/11 18:40, Emergency Response Team started to operate - Analyzing air trajectory and diffusion - Strengthening the environment radiation monitoring (1 st step) 03/11 16:40, KINS reported accident situation to MOST (former NSSC) 10

11 03/23, Radioactive Xe was detected 03/26, 1 st Marine monitoring program implemented 11

12 03/29, 131 I was detected in air suspension sampled in 28 March 03/28, Strengthening the environment radiation monitoring (2 nd step) 12

13 Temporal variation of 131 I activities in airborne dust samples at 12 regional monitoring stations At April 6, the maximum 131 I was detected. 3.5 Activity concentration in air particle (mbq m -3 ) /4/6 Seoul Chuncheon Daejeon Gunsan Gwangju Daegu Busan Jeju Gangneung Andong Suwon Cheongju 27/03 31/03 04/04 08/04 12/04 16/04 20/04 24/04 28/04 Sampling date 13

14 Temporal variation of 134 Cs and 137 Cs activities in airborne samples at 12 regional monitoring stations At April 6, the maximum 134 Cs and 137 Cs were detected. 11/4/6 11/4/6 Activity concentration in air particle (mbq m -3 ) /04 A) 05/04 09/04 13/04 17/04 21/04 25/ Seoul Chuncheon B) Daejeon Cs Gunsan Gwangju Daegu 1.0 Busan Jeju 137 Cs Gangneung 0.8 Andong Suwon Cheongju /04 03/05 07/05 11/05 15/05 19/05 23/05 27/05 01/06 Activity concentration in air particle (mbq m -3 ) /03 31/03 04/04 08/04 12/04 16/04 20/04 24/04 28/04 02/05 06/05 10/05 14/05 18/05 Seoul Chuncheon Daejeon Gunsan Gwangju Daegu Busan Jeju Gangneung Andong Suwon Cheongju 22/05 26/05 30/05 Sampling date Sampling date 14 14

15 (msv) 100 Biological effect: scientifically known region 10 CT/PET dose 1 Annual public dose limit Nat. Dose/yr Chest-X ray WHO portable water dose/yr Rain/Jeju I-131 dose/yr Rain/Jeju Cs-137 dose/yr Airborne/Seoul Cs-137 dose/yr Airborne/Seoul I-131 dose/yr (msv) 15

16 Impacts to Korean Marine Env.(1) Radioactivities in Seawater 137 Cs concentration in Seawater ( ~ ) : ND ~ 4.77 mbq/l Year No. of samples 134 Cs (mbq/kg) 137 Cs (mbq/kg) ND ND ~ ND ~ ND ND ~ ~6 81 ND ND ~ 4.77 Avg. Concentration in Seawater (1996 ~ 2010) Cs : ND Cs : ND 7.00 mbq/l 16

17 Impacts to Korean Marine Env.(2) Radioactivities in Fish 137 Cs concentration in Fish ( ~ ) : ND ~ 2.43 Bq/kg Year Number of samples 134 Cs (Bq/kg) 137 Cs (Bq/kg) 40 K (Bq/kg) ND ND ~ ~ ND ~ 1.72 ND ~ ~ ND ND ~ ~ ~6 35 ND ND ~ ND ~ 98.5 Avg. Concentration in Fish (1996 ~ 2010) Cs : ND Cs : ND ~ Bq/kg 17

18 Understanding of Fukushima Disaster by Korean Public

19 RADIOACTIVE MATERIALS ~ ~ iltl~it L.t.2[ ~ JJ-'1 - ~!f.-&239, AU<e-137-f: 'd±9t '!l~ct ~- llti\- t"iltll. ~n'1!oaa1 7J~o~. -i<a~oj. ~~ ~ ~~~137 -~~~91~) 19 19

20 Misunderstanding & Truth Westerlies KMA 4/1 (D+21) Radioactivity Rain 4/6 (D+26) 20

21 Background information on the perception of radiation risk by the Korean public after Interest of the public in radiation risk has been significantly heightened - Public began to buy radiation detectors and started to measure radiation levels in their nearby living environment such as schools, super market, playground etc. - Through the well-developed SNS, during the year of 2011, several anti-nuclear Web communities of general public such as ChildSave and KnowLive.Net have been formulated and continue to work very actively and to lead the public opinion. 21

22 Background information on the perception of radiation risk by the Korean public after 3.11 Post-nuclear Professors Association ( 11.11) Anti-nuclear MD Association ( 12.1) No-nuclear Lawyers Association ( 12.2) Foundation of Green Party ( 12.3) No-NUKE Schools Association ( 12.6) MP Study Group for No-nuclear Energy ( 12.2/6) MP Study Group for No-NUKE to Children ( 12.7) 22

23 Summary: Perception of radiation risk by the Korean public after 3.11 Concerns about the risk at low doses is very much present and amplified among the population. Experts tried to mitigate health concern and - failed to find ways to discuss about the tolerability of radiation risk and risk comparison, and to inform the public of scientific knowledge on risk. Some tried to enlarge health concern and - Anti-nuclear NGOs strengthened their activities with some political intention; - Ghost stories (unfounded rumor) were quickly and widely spread through SNS. Loss of trust in Governmental measures Loss of credibility in Government-based experts 23

24 RP Issues in Korea after F: Practices

25 1. Public road contaminated with Cs-137 (November 2011) Road Contamination Cs-137 detected in roads < Seoul > 25

26 2. Wall paper manufactured with high Th (December 2011) Wall Paper Manufactured intentionally with high contents of natural radionuclides (U-238, Th-232) < Wall paper in a house > 26

27 3. Kitchen utensil contaminated with Co-60 (January 2012) Kitchen utensil Co-60 contaminated in a plate rack 27

28 4. Failure of isolation of I-131 therapy patient (January 2012) I-131 patient I-131 administered thyroid cancer patient released out of hospital ( 12.1) 28

29 29

30 OID~E ~1.11~ *~~ ~HQII ~~~ 8-!f-1 : %, ~\:1 ~i! Ql~l 2013\:18~ 9~ 10~ 12~ 2:5r ~20"'"'''"''''''''"'"' D 201~s-w ~R Oi~ ~H ~~ ~ 12!! 2.~0i

31 RP Issues in Korea after F: Principles Q. What is safe level?

32 Is it safe, if it s under the limit? (No-NUKE Blog, Aug. 10, 2013) Since, the Cs-137 limit for fish in Korea is 370 Bq, 0.1 is under the limit and 369 Bq is also under the limit. While the Cs-137 limit in Japan is 100 Bq. It can t be said safe, though it s under the limit. It s better to reduce the exposure as much as possible, since medical health standard tells that exposure is directly proportional to cancer fatality. Limit doesn t mean safe medically. Limit is not the value with medical background. Medical experts speak conclusively There is no safe exposure. 32

33 Can t we say it s safe, unless the dose becomes zero? There is no safe radiation dose, since the research results and the textbook in medical school tell that as the exposure increases, the cancer incidence also increases. There is a direct correlation between the increase of radiation dose, though it s a tiny, and the increase of the number of cancer patients. No matter how small the dose is, nobody can affirm that there is no health effect from the dose. 33

34 Isn t the limit too high? The Cs-137 limit for fish in Korea is crazily high. This is equivalent to the activity level in sea water in front of the FDNPS site. The limit shall be reduced. One hundredth of 370 Bq/kg would be appropriate. the activity level in all shorefish is less than 1 Bq. IPPNW, a Nobel prize laureate, suggests that 8 Bq/kg for adult and 4 Bq/kg for children as the limit. Germany already accepted this limit. Comparing with the Korean limit, these values are extremely low. 34

35 < What is safe level? > In the public debates hosted by news media, a few MDs in the occupational and environmental medicine area argued that there is no safe level in radiation exposure due to LNT model. In the case of cancer, epidemiological and experimental studies provide evidence of radiation risk albeit with uncertainties at doses about 100 msv or less. (ICRP 103, para. 62) 35

36 < What is safe level? > Linear Non-Threshold (LNT) Hypothesis (Stochastic Effects Limits of knowledge) Cancer Fatality 5%/Sv For most tumour types in experimental animals and in man a significant increase in risk is only detectable at doses above about 100 mgy. UNSCEAR 2000 Doses where cancers have been observed Doses of relevance in radiation protection 100 msv 36

37 Cancer incidence 10%/Sv FIGURE PS-4 In a lifetime, approximately 42 (solid circles) of 100 people will be diagnosed with cancer (calculated from Table 12-4 of this report). Calculations in this report suggest that approximately one cancer (star) per 100 people could result from a single exposure to 0.1 Sv of low-let radiation above background. 37

38 Individual dose level Unacceptable risk Tolerable risk Dose limit Dose constraint Optimisation process ALARA level Courtesy of Ms. Ann McGarry, ICRP C4 38

39 Scientific understanding is that 100 msv is the borderline between safe and unsafe food and feed. Public and political understanding is that any level is a borderline between safe and unsafe food and feed. 39

40 RP Issues in Korea after F - Summary - 1. Non-expertise experts were the sources of the confusion and misperception on the radiation risk by the public (i.e. excessive concern on the risk of low doses), especially in a country where no cultural background of discussion & debate exists. 2. Strong need to disseminate the correct information about the harms of the ionizing radiation and the knowledge of how much the low doses can be harmful to the health (LNT) 1) Need to re-consider the value of public dose limit & the use of the terminology limit in describing the radiation dose level 2) Need to describe the RP principles in easiest way 40

41 Conclusion

42 Current Situations in Korea 1. Failure in communication with the public about the magnitude of radiation risk and its tolerability 2. Loss of trust in government and its experts 3. Weak base of radiation protection specialists 4. Strongly increased voices of anti-nuclear groups 42

43 Suggestions for the Future of Korea Continuous Strengthening of National Human and Material Infrastructure for Radioactivity Analysis Improvement of Reliability of Radioactivity Measurement and Analysis Secure of Radioactivity Analysis Capability for possible similar scale NPP accident Recognition of Big Gap between the True and Perceived Level of Radiation Risk and its Resolution Openness of All Radiation Safety Related Information to the Public in More Active Ways and Means including SNS Development of Measures for Clearer and Easier Communication on Radiation Risk Strong Governmental Support for All Radiation Risk Communication Efforts by Experts Strengthening of Governmental Control Tower for Radiation Safety Establishment of Integrated System for Rapid and Coordinated Government Response Continuous Strengthening of the Role and Function of Nuclear Safety and Security Commission as Governmental Control Tower for Radiation Safety 43

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45 Conclusion I have spoken to you of earthly things and you do not believe; how then will you believe if I speak of heavenly things? (John 3:12) Society of Distrust Society of Trust 45

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