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Gustavo Massera Autoridad Regulatoria Nuclear Argentina

Gustavo Massera Autoridad Regulatoria Nuclear Argentina. Introduction. In the aftermath of a nuclear or radiological accident much attention is focused on radionuclide contamination of food, and water trough related standards including operational intervention level. Set of recommendations.

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Gustavo Massera Autoridad Regulatoria Nuclear Argentina

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  1. Gustavo Massera Autoridad Regulatoria Nuclear Argentina

  2. Introduction In the aftermath of a nuclear or radiological accident much attention is focused on radionuclide contamination of food, and water trough related standards including operational intervention level

  3. Set of recommendations • Several international standards relating to radionuclides in food and drinking water from different IOs • Guideline values differ for each exposure circumstance • Several set of values exist in use • Reasons, value deriving criteria and circumstances for their application are not always clear

  4. Codex Alimentarius Revisión • In March 2012 theCodexCommitteeonContaminats in foods (CCCF) proposedthe revisión of theCodexGuidelinelevels of radionuclides in foodtradedinternationallyfollowing a nuclear or radiological emergency existing in theCodex General Standard for Contaminants and Toxins in Food and Feed (CODEX STAN 193-1995). • Forthepurposeitwasnotedtheimportance of involvingthe International AtomicEnergyAgency and otherrelevantorganizations.

  5. Radiation Safety Standards Committee (RASSC) Proposal • The issue was discussed at the 2012 mid-year Radiation Safety Standards Committee (RASSC) meeting when existing problems to interpret and apply the guidance were apparent from the experience following the Fukushima nuclear accident. • From the floor discussion during the meeting it was accepted the convenience that an inter-agency Working Group would best deal with the revision work on the existing guidance

  6. Inter-Agency Working Group • The inter-agency W G was established by the IAEA Secretary with representatives of the Secretariat of the Codex Alimentarius Commission, the Food and Agriculture Organization (FAO), the International Atomic Energy Agency (IAEA), the World Health Organization (WHO), the Nuclear Energy Agency (NEA/OECD), and the European Commission (EC), with the International Commission on Radiological Protection (ICRP) as an observer. • Meetings where held during 2013 including experts consultants

  7. ToR of the WG • The terms of reference for the WG was established as follows: • Summarize the current international standards for radioactivity in food and water for human consumption • Document examples of national standards • Identifies possible missinterpretation and/or gaps in the existing international standards • Proposes steps that need to be taken by the IOs to facilitate the recognition, understanding and implementation of the international standards.

  8. Concept of Exposure Situations • In terms of the degree of control available on the source of radiation and the expected durantion time three different exposure situation are introduced by ICRP designated as, • Planned, • Emergency and • Existing

  9. Planned exposure situation, currently regulated activities that may continue for long periods of time

  10. Emergency exposure situation, may apply on for days or months until control of the situation is regained and the resulting radiological hazards completely characterized Nuclear accident Emergency

  11. Existing exposure situations, (Post emergency) further protection action are taken to protect people living in contaminated areas based on careful assessment of the conditions. Affected territory Exposure control for resetlement Remediation

  12. IAEA Guidance • The criteria applied in its guidance and requirements by IAEA is compatible with reference levels within a range of 20 to 100 mSv acute exposure or 1 to 20mSv per year dose reference level values introduced by ICRP in Publication 103, (2007) for emergency and existing exposure situations respectively. • Main IAEA publications considered, • General Safety Guide GS-G-2 on “Criteria for use in preparedness and response for a nuclear or radiological emergency”, IAEA, (2002) under revision. • General Safety Requirement Part 3 “International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources”, IAEA, (2014)

  13. IAEA Guidance • Provides operational criteria to be used for prompt initiation of protective actions for acute and prolonged per year for all pathways that applies to radionuclides (e.g. restricting the consumption of food, milk and water). Calculated on the basis of dose criteria of 10 mSv per year for ingestion on the conservative assumption that: • All of the food, milk and drinking water are initially contaminated and are consumed throughout the full year • The most restrictive age dependent dose conversion factors and ingestion rate (i.e. for infants) are used, hence all age groups are covered.

  14. Summary IAEA Guidance

  15. World Health OrganizationGuidance for drinking water • Guidelinesfordrinkingwaterquality - 4thedition, Chapter 9, WHO, (2011) - do notapplytoemergencyexposuresituations. • Therecommendedlevels are forprolongedexposure of thepublicforwhich case it consideres prudenttokeep individual dosecontributionfromdrinkingwaterbelow 0.1 mSV per year. Regardless of theoriging (plannedorexistingexposuresituations) of contaminatingradionuclides.

  16. Summary WHO guidance for drinking water

  17. Codex: GLs for International Trade • Codex General Standard for Contaminants and Toxins in Food and Feed (CODEX STAN 193-1995) provides Guideline Levels for Radionuclides in Foods Contaminated Following a Nuclear or Radiological Emergency • For international trade destined for human consumption

  18. Codex Criteria • Generic intervention exemption level: 1 mSv/y for ingestion. • Activity concentrations are derived assuming 10% of the diet is imported food, all of which is contaminated (i.e., import to production factor (IPF) of 0.1). • Levels may be increased by a factor of 10 for food consumed in small quantities

  19. Radioniclides in the Codex GLs • Radionuclides (20 in total) included in the GLs are important for uptake into the food chain. These radionuclides are usually contained in nuclear installations or used in radiation sources in large ammounts that could be accidentally or intencionally released and significantly contribute to food contamination • Due to infant sensitivity, radionuclides are separated in two categories “infant food” and “other food” • Radionuclides from natural origin are excluded from consideration. Their contribution only amounts from few tens to hundreds microsivert per year.

  20. Summary Codex GLs

  21. Exposure assessment • The mean fraction of major foodstuff imported by all countries worldwide is in the order of 0.1 (FAO) • GLs are derived to ensure that the mean annual internal dose of the population from consumption of foods imported from affected countries will not exceed 1 mSv in a year • If GLs are exceeded, national governments shall decide whether and under what circumstances the food should be distributed Examples of dosecalculation Adults: Dose =1000Bq/kg . 550kg/y . 1.3 10-5mSv/Bq . 0.1= 0.7 mSv/y Infants: Dose =1000Bq/kg . 200kg/y . 1.3 10-5mSv/Bq . 0.1= 0.7 mSv/y

  22. Choice of applicable international standard for food and drinking water Affected Countries (contaminated local food) International trade of food Codex Guideline Levels Emergency exposure situation Existing exposure situation GSG-2 operational intervention levels for food and drinking water No guidance for food in affected country WHO guidelines for drinking water

  23. Conclusions from the WG • No major gaps in international standards on radionuclides in food and water were found by the WG • A number of areas were identified where steps could be taken to improve understanding and implementation • There are still some technicall issues to be solved, such as stage of food production and guidance value for water in existing exposure situation

  24. Codex Technical Issues Recommended to be Resolved • The stage of food production to which the guidelines applies • The period of time the GL should apply in food trade following a nuclear or radiological accident • The identification of internationally validated methods of analysis for radionuclides in food • The development of sampling plans to enhance the implementation of the Codex GLs

  25. Other Key Recommendations • Member States are encouraged to ensure that appropriate coordination across all relevant Government bodies is established to ensure proper standards will be effectively implemented. • IO s with a role in developing standards, to considerer helpful to users that all operational criteria be derived according to the protection needs of the most vulnerable groups and so generate just one value for the entire population. • WHO should consider its guideline levels in the existing exposure situation (post-emergency) in terms of moving to a common dose criterion for ingestion (food and drinking water) of 1mSv

  26. Actions by RASSC • RASSC in its 35th meeting in November 2013 discuss the paper and concluded that while there are no major gaps in existing international standards, better harmonization of standards would be desirable given the disparities among MS for implementation. • It was also recognized the complexity of the matter and the need to address different instances such as accident state, neighboring affected state and other states in a consistent manner, and the extent of the time for their application. • The proposal for drafting of TEC-DOC followed the discussion of the paper from WG

  27. Conclusions and Action by the CCCF • From the feed back and conclusion provided by the WG to the CCCF it was decided to maintain discontued the work on the development of guidance to facilitate interpretation of the WG results and recommendations in view to start future work on radionuclides content in food as necessary.

  28. Many thanks Autoridad Regulatoria Nuclear Av. del Libertador 8250 (C1429BNP) Ciudad Autónoma de Buenos Aires, ARGENTINA Tel.: (+54) (011) 6323-1770 Fax: (+54) (011) 6323-1771/1798 http:// www.arn.gob.ar Mail: info@arn.gob.ar

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