United States Air And EPA 520/1-89-032 Environmental Protection Radiation September 1989 Agency (ANR-459) &EPA Protective Action Guides For Accidentally Contaminated Water And Food Proceedings Of A Workshop Held In Washington, DC September 1989 \ ------- PROTECTIVE ACTION GUIDES FOR ACCIDENTALLY CONTAMINATED WATER AND FOOD PROCEEDINGS OF A WORKSHOP HELD IN WASHINGTON, D C SEPTEMBER 1989 Office of Radiation Programs U.S. Environmental Protection Agency Washington, D C 20460 ------- PROCEEDINGS OF A WORKSHOP ON PROTECTIVE ACTION GUIDES FOR ACCIDENTALLY CONTAMINATED WATER AND FOOD CONTENTS Page Introduction to Workshop 1 List of Workshop Participants and Working Group Assignments 3 Workshop Agenda 11 Speakers' Papers 13 Overview of Workshop Objectives, by Joe E. Logsdon 15 Experience in Exercise Evaluations, by George E. Bickerton 19 Existing Ingestion Guidance: Problems and Recommendations, by Robert Mooney, Gordon L. Ziegler, and Donald S. Peterson 27 Concerns for the Human Element in Implementing Protective Action Guides, by Aby Mohseni, Aileen Jeffries, and Paul Fedorchak 35 Problems Related to Public Perceptions of Radiological Emergency Planning and Response, by Margaret A. Reilly 43 International Commerce and the Chernobyl Experience, by Ronald (Skip) Engel, Victor Randecker, and Wesley Johnson 47 International Guidance Activities, by Allan C.B. Richardson 55 Economic Criteria for Implementing PAGs for Food, by Byron M. Bunger .... 61 Submitted Papers 69 Issues Regarding the U.S. F.DA. Protective Action Guidelines and Derived Response Levels for Human Food and Animal Feed, by Bruce Denney 71 Concerns in Assessing Radiological Releases to a Major Estuary, by Leslie P. Foldesi 73 111 ------- The Ingestion Pathway Comments and Issues, by Lawrence J. McDonnell .... 75 Implications of the Chernobyl Accident for Protective Action Guidance, by Charles W. Miller, Andrea J. Pepper 77 PAGS - Public Perception and Acceptance, by Robert M. Quillin 81 New Jersey's Experience with Implementing Protective Action Guides During the 1988 Salem Ingestion Pathway Exercise, by Duncan White 83 Working Group Summaries 87 Working Group One For what Protective Actions and Situations are Ingestion PAGs Needed? 89 Working Group Two What Considerations should be Evaluated in the Process of Selecting PAG Values for Ingestion Pathways? 93 Working Group Three What Considerations are Important for the Development of Guidance for Protection from Contaminated Water? 99 Working Group Four What Guidance is Needed to Support Implementation of PAGs for Ingestion Exposure Pathways? 103 Appendices 109 A Proposed FAO/WHO Levels for Radionuclide Contamination of Food in International Trade Following an Accidental Nuclear Release Ill B. Accident in the Southern Urals on 29 September, 1957, by B.V. Nikipelov, G.N. Romanov, L.A. Buldakov, N.S. Babaev, Yu.B. Kholina and E.I. Mikerin 119 IV ------- INTRODUCTION The Workshop on Protective Action Guides for Accidentally Contaminated Water and Food was designed for those who have experience in planning for and responding to ingestion exposure scenarios. The objective was to identify and discuss all of the issues, problems, relevant experiences, and research that should be considered in the development of Protective Action Guides (PAGs) for water and food. The workshop was not designed to produce consensus conclusions or recommendations, but rather provide a forum for discussion of problems, debate of solutions, and exchange of ideas. The workshop consisted of two plenary sessions and one working group session. This first plenary session consisted of a variety of speakers with State and Federal perspectives on the issues and it provided background information for the working group sessions. The second plenary session consisted of presentations and discussions from the working groups, which met in sessions to address four different issues. The workshop proved to be very helpful for those responsible for developing PAGs for the ingestion exposure pathways. The Environmental Protection Agency (EPA), the Department of Agriculture (USDA) and the Conference of Radiation Control Program Directors (CRCPD) were cosponsors of this event. The planning committee for the workshop consisted of Aubrey Godwin from the CRCPD, George Bickerton and Ronald (Skip) Engel from USDA, and Allan Richardson and Joe Logsdon from EPA. They were responsible for the organization of the workshop and the selection of key participants, speakers, and session leaders. Cheryl Malina from EPA had primary responsibility for executing the plans of the workshop. In addition to participants from the sponsoring organizations, representatives from the Health Physics Society, the Food and Drug Administration (FDA), the Department of Energy (DOE), the Nuclear Regulatory Commission (NRC), and the Federal Emergency Management Agency (FEMA) were in attendance. This workshop addressed the roles and responsibilities for the development of PAGs. EPA has the responsibility for development of PAGs, except in the case of PAGs for food for which the responsibility is shared with FDA. EPA participated in the development of the recommendations on PAGs for food and animal feed that FDA published in 1982, which are under revision. In the absence of PAGs specifically for water, past practice has been for EPA to provide ad. hoc. guidance when needed. EPA will be developing guidance for drinking water during the next fiscal year and, therefore, one of the working groups at the workshop was devoted to considering issues related to PAGs for water. It has not yet been determined whether PAGs for drinking water should be separate or included with those for food. These issues were discussed at the workshop and the recommendations included in this proceedings document will be used a resource in the development of PAGs for the ingestion pathway. For more information or additional copies of this document contact Joe E. Logsdon, at the Guides and Criteria Branch, Office of Radiation Programs, EPA, 401 M Street, S.W. (ANR-460), Washington, D.C. 20460, (202) 475-9620. ------- WORKSHOP ON PROTECTIVE ACTION GUIDES FOR ACCIDENTALLY ACCIDENTALLY CONTAMINATED WATER AND FOOD PARTICIPANTS Mr. William Belanger Radiation Representative U.S. Environmental Protection Agency ~ Region 841 Chestnut Street (3AH14) Philadelphia, PA 19107 (215) 597-4084 Mr. George Bickerton Director, Office of Emergency Planning Food Safety and Inspection Service U.S. Department of Agriculture, Room 2940-S 14th and Independence Streets, S.W. Washington, D.C. 20250 (202) 475-3683 Mr. Byron Bunger Economist Economics and Control Engineering Branch Office of Radiation Programs U.S. Environmental Protection Agency 401 M Street, S.W. (ANR-461) Washington, D.C. 20460 (202) 475-9644 Mr. Bruce Burnett (Observer) Senior Engineer Food and Drug Administration (HFZ-60) 5600 Fishers Lane Rockville, MD 20857 (301) 443-2850 Mr. Robert Conley Emergency Programs Specialist Office of Emergency Planning Food Safety and Inspection Service U.S. Department of Agriculture 14th and Independence Streets, S.W. Washington, D.C. 20250 (202) 475-3683 Mr. William C. Cunningham (Observer) Research Chemist Food and Drug Administration (HFF-426) 5600 Fishers Lane Rockville, MD 20857 (301) 975-6271 Mr. Lawrence B. Czech Assistant Director for Technical Services New York State Emergency Management Office State Campus Building, No. 22 Albany, NY 12226-5000 (518) 457-8909 Mr. Bruce Denney Health Physicist Minnesota Department of Health 717 S.E. Delaware Street P.O. Box 9441 Minneapolis, MN 55440 (612) 623-5350 Mr. Doug Collins Chief, Emergency Preparedness and Radiation Protection Branch Nuclear Regulatory Commission 101 Marietta Street Atlanta, GA 30323 (404) 331-5584 FTS 242-5584 Dr. Ronald E. (Skip) Engel Assistant to the Administrator International Scientific Liaison Food Safety and Inspection Service U.S. Department of Agriculture 14th and Independence Streets, S.W. - Room 3165 Washington, D.C. 20250 (202) 447-2326 ------- Mr. Leslie Foldesi Director, Bureau of Radiological Health Virginia Department of Health 109 Governor Street Richmond, VA 23219 (804) 786-5932 Mr. S.W. Felix Fong Chief, Nuclear Facility and Environmental Radiation Surveillance Section North Carolina Division of Radiation Protection Department of Human Resources .701 Barbour Drive Raleigh, NC 27603 (919) 733-4283 Mr. Aubrey Godwin Director, Radiological Health Branch Alabama Department of Public Health State Office Building - Room 510 434 Monroe Street Montgomery, AL 36130-1701 (205) 261-5315 Mr. Charles W. High Emergency Planning Coordinator Bureau of Radiation Protection Pennsylvania Department of Environmental Resourc P.O. Box 2063 Harrisburg, PA 17120 (717) 787-3479 Mr. Joe Keller Fellow Scientist Idaho National Engineering Lab P.O. Box 4000 Idaho Falls, ID 83403 (208) 526-2123 Mr. Joe Logsdon Certified Health Physicist Guides and Criteria Branch Office of Radiation Programs U.S. Environmental Protection Agency 401 M Street, S.W. (ANR-460) Washington, D.C. 20460 (202) 475-9620 Mr. Bernis O. Hannah Director, Emergency Planning and Environmental Monitoring Section Radiological Health Branch Alabama Department of Public Health State Office Building ~ Room 510 434 Monroe Street Montgomery, AL 36130-1701 (205) 242-5315 Mr. Thomas Heim (Conference Management Support) Associate ICF Incorporated 9300 Lee Highway, #446 Fairfax, VA 22031 (703) 934-3791 Ms. Cheryl Malina Emergency Programs Specialist Guides and Criteria Branch Office of Radiation Programs U.S. Environmental Protection Agency 401 M Street, S.W. (ANR-460) Washington, D.C. 20460 (202) 475-9620 Mr. Dave McCormack Battelle P.O. Box 999 Mail Stop K3-54 Richland, WA 99352 (509) 375-2429 ------- Mr. Lawrence McDonnell Staff Scientist State of Wisconsin Radiation Protection Council 5708 Odana Road Madison, WI 53719 (608) 273-6437 Mr. Robert Mooney Head, Environmental Radiation Section Division of Radiation Protection Department of Health (MS LE-13) Olympia, WA 98504 (206) 586-3303 Mr. Thomas McKenna Incident Response Branch Nuclear Regulatory Commission Washington, D.C 20555 (301) 492-4184 Mr. Gary W. McNutt Radiological Health Analyst Missouri Department of Health P.O. Box 570 1730 E. Elm Street Jefferson City, MO 65109 (314) 751-6083 Mr. Charles W. Miller Chief, Division of Planning and Analysis Illinois Department of Nuclear Safety 1035 Outer Park Drive Springfield, IL 62704 (217) 785-9889 Mr. Michael H. Mobley Director, Division of Radiological Health 150 9th Avenue, North Nashville, TN 37219-5404 (615) 741-7812 Mr. Aby Mohseni Division of Radiation Protection Department of Health (MS LE-13) 217 Pine Street, Suite 220 Seattle, WA 98101-1549 (206) 464-7274 Mr. T. Pearce O'Kelly Director, Division of Electronic Products Bureau of Radiological Health South Carolina Department of Health and Environmental Control 2600 Bull Street Columbia, S.C. 29201 (803) 734-4700 Ms. Andrea J. Pepper Emergency Planning Section Head Illinois Department of Nuclear Safety 1035 Outer Park Drive Springfield, IL 62704 (217) 785-9890 Mr. Robert M. Quillin Director, Radiation Control Division Colorado Department of Health 4210 East llth Avenue Denver, CO 80220 (303) 331-8480 Mr. Victor Randecker Environmental Engineer Food Safety and Inspection Service U.S. Department of Agriculture 300 12th Street, S.W. Room 402 Washington, D.C. 20250 (202) 447-2428 ------- Mr. Thomas Reavey Environmental Scientist Guides and Criteria Branch Office of Radiation Programs U.S. Environmental Protection Agency 401 M Street, S.W. (ANR-460) Washington, D.C. 20460 (202) 475-9620 Ms. Margaret A. Reilly Chief, Division of Environmental Radiation Bureau of Radiation Protection Pennsylvania Department of Environmental Resources P.O. Box 2063 Harrisburg, PA 17120 (717) 787-3479 Mr. Allan Richardson Chief, Guides and Criteria Branch Office of Radiation Programs U.S. Environmental Protection Agency 401 M Street, S.W. (ANR-460) Washington, D.C. 20460 (202) 475-9620 Dr. Karim Rimawi Bureau of Environmental Radiation Protection New York State Department of Health Two University Place Albany, NY 12203 (518) 458-6461 Mr. Dave Rohrer Health Physicist Office of Safety, Policy and Standards U.S. Department of Energy (EH352) Washington, D.C. 20545 (301) 353-5609 Mr. Robert J. Schell Nuclear Engineer Specialist State of Maine Radiation Control Program State House Station 10 Augusta, ME 04333 (207) 289-5676 Mr. Gail Schmidt (Observer) Certified Health Physicist Food and Drug Administration 10025 Lloyd Road Potomac, MD 20854 (301) 424-3151 Dr. Bernard Shleien Representative, Health Physics Society Scinta Inc. 2421 Homestead Drive Silver Spring, MD 20902 (301) 593-9478 Mr. Peter Stang Health Physicist Office of Emergency Planning Food and Safety Inspection Service U.S. Department of Agriculture Washington, D.C. 20250 Mr. Marlow Stangler Emergency Management Specialist Federal Emergency Management Agency 500 C Street, S.W. Washington, D.C. 20472 (202) 646-2856 Mr. Stephen Stasolla Section Supervisor New Jersey Department of Environmental Protection Bureau of Nuclear Engineering (CN-415) Trenton, NJ 08625 (609) 987-2032 ------- Mr. Allan C. Tapert Bureau of Environmental Health Office of Radiation Control Cooper Building, Capitol Square P.O. Box 637 Dover, DE 19903 (302) 736-4731 Ms. E. Archer Taylor (Conference Management Support) Associate ICF Incorporated 9300 Lee Highway Fairfax, VA 22031 (703) 934-3168 Mr. Kenneth L. Travis Chairman State and Federal Legislation Committee Health Physics Society 8123 Truro Court Springfield, VA 22152 (703) 644-5655 Mr. Duncan White Health Physicist Bureau of Nuclear Engineering (CN-415) New Jersey Department of Environmental Protection Trenton, NJ 08625 (609) 987-2032 Mr. Vern Wingert Emergency Management Specialist Federal Emergency Management Agency 500 C Street, S.W. Washington, D.C. 20472 (202) 646-2872 ------- WORKSHOP ON PROTECTIVE ACTION GUIDES FOR ACCIDENTALLY CONTAMINATED WATER AND FOOD WORKING GROUP ASSIGNMENTS WORKING GROUP I Bruce Denney: Chairman George Bickerton Bruce Burnett Douglas Collins Lawrence Czech Skip Engel Lawrence McDonnell Pearce O'Kelly Allan Richardson Dave Rohrer WORKING GROUP U Charles Miller: Chairman Byron Bunger Joe Logsdon Gary McNutt Robert Quillin Karim Rimawi Bernard Schleien Gail Schmidt Peter Stang Kenneth Travis WORKING GROUP HI Michael Mobley: Chairman George Brown Leslie Foldesi Aubrey Godwin Charles High Dave McCormack Thomas McKenna Aby Mohseni Thomas Reavey Margaret Reilly Allan Tapert WORKING GROUP IV Duncan White: Chairman William Belanger William Cunningham Felix Fong Robert Mooney Andrea Pepper Robert Schell Marlow Stangler Stephen Stasolla Vern Wingert ------- WORKSHOP ON PROTECTIVE ACTION GUIDES FOR ACCIDENTALLY CONTAMINATED WATER AND FOOD Pan American Health Organization 525 Twenty-Third Street N.W. Washington, DC September 13-14, 1989 AGENDA Workshop Objective The principal objective was to identify and discuss issues that require consideration in the development of recommendations to protect the public from accidentally contaminated water and food. It was not expected at this workshop that issues would be resolved or guidance developed. September 13, 1989 Plenary Session 8:30 to 8:45 Registration (ICF) 8:45 to 9:00 Welcome and Introduction ~ Aubrey Godwin, CRCPD 9:00 to 9:20 Overview of Workshop Objectives ~ Joe E. Logsdon 9:20 to 9:40 Experience in Exercise Evaluations - George E. Bickerton, USDA 9:40 to 10:00 Existing Ingestion Guidance: Problems and Recommendations - Robert Mooney, State of Washington 10:00 to 10:20 Concerns for the Human Element in Implementing Protective Action Guides ~ Aby Mohseni, State of Washington 10:20 to 10:40 Break 10:40 to 11:00 Problems Related to Public Perceptions of Radiological Emergency Planning and Response - Margaret A. Reilly, State of Pennsylvania 11:00 to 11:20 International Commerce and the Chernobyl Experience ~ Ronald (Skip) Engel, USDA 11 ------- AGENDA (continued) 11:20 to 11:40 International Guidance Activities -- Allan C.B. Richardson, EPA 11:40 to 12:00 International Activities on Criteria for Food -- William Cunningham, FDA 12:00 to 1:10 Lunch 1:10 to 1:30 Cost of Implementing PAGs for Food - Byron M. Hunger, EPA 1:30 to 1:45 Review of Issues Raised in Presentations -- George E. Bickerton, USDA Working Group Session 1:45 to 2:00 Organization of Working Groups - Joe E. Logsdon, EPA 2:00 to 5:00 Working Group Discussions and Preparation of Summary Reports September 14, 1989 9:00 to 9:30 Working Groups Meet to Organize Presentations Plenary Session 9:30 to 10:30 Working Groups One and Three Presentations and Audience Participation; Moderator - Joe E. Logsdon, EPA 10:30 to 11:00 Break 11:00 to 12:00 Working Groups Two and Four Presentations and Audience Participation; Moderator - George E. Bickerton, USDA 12:00 to 1:30 Lunch 1:30 to 3:00 Audience Discussion and Review of the Most Important Issues - Aubrey Godwin, CRCPD 3:00 to 3:30 Closing Remarks and Adjournment -- Allan C.B. Richardson, EPA 12 ------- SPEAKERS' PAPERS ------- Overview of the Workshop Joe E. Logsdon Office of Radiation Programs US Environmental Protection Agency Washington, DC Introduction: Welcome to the Workshop on Protective Action Guides for Accidentally Contaminated Water and Food. The organizers have put forth considerable effort to bring it all together, and I believe it will prove invaluable to the Federal agencies responsible for developing Protective Action Guides (PAG) for the ingestion exposure pathways. I hope the other participants will also benefit from the discussions. This will be a presentation of the reasons for and the objectives of the workshop and our plans for its operation and the use of its product. Participants and Roles: The Environmental Protection Agency (EPA), the Department of Agriculture (USDA) and the Conference of Radiation Control Program Directors (CRCPD) are cosponsors of this workshop. Our planning committee for the workshop consisted of Aubrey Godwin from the CRCPD, George Bickerton and Ronald (Skip) Engel from USDA and Allan Richardson and myself from EPA. We were responsible for the organization of the workshop and the selection of key participants, speakers, and session leaders. Cheryl Malina from EPA has been primarily responsible for making everything happen as planned. In addition to participants from the sponsoring organizations, we - have representatives from the Health Physics Society, the Food and Drug Administration (FDA), the Department of Energy (DOE), the Nuclear Regulatory Commission (NRC), and the Federal Emergency Management Agency (FEMA). We attempted to hold the number of participants to a level that could function effectively as a workshop and, therefore, had to reject many requests for attendance. EPA has the responsibility for development of PAGs except in the case of PAGs for food, the responsibility is shared with FDA. EPA participated in the development of the recommendations on PAGs for food and animal feed that FDA published in 1982. However, we had some remaining problems with them and were never able to get internal concurrence to publish them in the Manual of Protective Action Guides and Protective Actions for Nuclear Incidents (PAG manual) as requested by FDA. FDA is now in the process of revising their 1982 recommendations and we want to make every effort to assure that when their revisions are complete, we can concur and publish them in the PAG manual as EPA recommendations. Since USDA and States have the major role in the implementation of PAGs for water and food, we plan to closely coordinate the development process with them. 15 ------- In the absence of PAGs specifically for water, past practice has been for EPA to provide ad. hoc. guidance when needed. We recognize that this is not satisfactory guidance for use in developing radiological emergency response plans. EPA will be developing guidance for drinking water during the next fiscal year and, therefore, we have devoted one of the working groups at this workshop to consider issues related to PAGs for water. It has not yet been determined whether PAGs for drinking water should be separate or included with those for food. This is an issue appropriate for discussion at this workshop. Workshop Objectives: This Workshop is designed as a forum for those who have experience in planning for and responding to ingestion exposure scenarios. The objective is to identify and discuss all of the issues, problems, relevant experiences, and needed or ongoing research that should be considered in the development of PAGs for water and food. We do not expect the workshop to produce consensus conclusions or recommendations. However, this does not preclude individuals from expressing opinions or making recommendations for consideration by the Federal agencies responsible for establishing guidance. It also does not prevent the presentation of consensus opinions if they develop, but we are not asking participants to spend their time trying to -each consensus. Although the Federal agencies will not be able to resolve all of the identified issues and problems to everyone's satisfaction, I expect that they will have at least considered them carefully and will be prepared to explain why they chose a particular approach or solution. This process should significantly reduce the need for changes to drafts of the guidance based on reviewer comments. Format for the Workshop: As you can see by the Agenda, the workshop consists of two plenary sessions and one working group session. This first plenary session will provide background information that may stimulate you to identify issues or problems that require discussion by the working groups. Each presentation in this session is scheduled for 15 minutes with an additional 5 minutes for questions. Although there is an overall constraint on time, I plan to be somewhat flexible with regard to individual presentations. In other words, we don't want to miss important information because of a time constraint, but on the other hand please don't feel obligated to use up the allotted time for presentations. If questions and discussions tend to be lengthy, they will be deferred to the appropriate working group in the next session. Working Groups: Each person has been assigned to one of the four working groups that will convene this afternoon. Each group will be addressing a different subject. Many of the participants have prepared papers for use by the working groups. We have reviewed them and attempted to sort them with regard to the appropriate group. Each working group will have set of the most relevant papers for their group and the Chairman will have a complete set. Some papers were relevant to more than one group and duplicates of these have been included for the additional group participants. This process should reduce the need for working group members to review nonrelevant papers. In most cases, authors papers have been assigned to the group that should 16 ------- have the most interest in his/her paper. I will provide additional information on the operation of the working groups at the time of their formation. Use of Workshop Results: The proceedings of the workshop will include an introduction followed by the papers that were presented in the plenary session and those that were prepared for use by the working groups. It will also include summaries prepared by the four working groups based on their discussions. The document will then be distributed to all of the attendees plus other interested parties. Most importantly, we plan to use it as a resource in the development of PAGs for the ingestion pathway. Thank you for coming. If you have any questions about the workshop, either now or later, please let me know. 17 ------- Experience in Exercise Evaluations George E. Bickerton Office of Emergency Planning Food Safety and Inspection Service United States Department of Agriculture Good morning. It's a real pleasure being here today. I have been asked to discuss our experience in exercise evaluations. USDA is unique among Federal agencies in the way we are organized to carry out our Radiological Emergency Response Program. All Radiological Assistance Committee functions have been centralized at Headquarters in the Food Safety and Inspection Service, Office of Emergency Planning, the staff which I head up. This means that all State and local radiological emergency response plans are reviewed by my staff, and all exercises that require USDA evaluators are provided evaluators from my office. This has resulted in a continuity and consistency in plan reviews and exercise evaluations that could not be achieved in a decentralized approach. It has also proved to be quite cost effective. The State and local governments in our opinion have come a long way in planning and exercising the plume exposure pathway. Most problems related to Alert and Notification, Sheltering and Evacuation have been resolved. As we begin the 6 year Ingestion Exposure Pathway exercise cycle, it appears we still have work to do. Let's begin by looking at some general areas of concern: Ingestion Exposure Pathway Plans Some States have not completed or even begun to make the ingestion related revisions to the State and local Radiological Emergency Preparedness Plans. The concern appears to center around cost, questions of format and questions of content. Basic guidance is provided in NUREG-0654 FEMA REP-1 and FEMA Guidance Memorandum GM IN-1. Without the plan we have a problem. A well defined plan is necessary for an effective emergency response and exercises are evaluated based on the plans. 19 ------- - Another problem relates to the Agricultural Brochure which has not yet been published. Since States will be required to provide site specific information and distribute the brochure within 120 days after it is on the street, this has posed another concern to the States. Ingestion Exposure Pathway Exercises - The plan must be exercised out to 50 miles instead of the 10 miles required for plume pathway exercises. This requires increased funding and often involves additional towns, cities, counties and adjacent States. - An unclear perspective of the role Federal Agencies could play in providing guidance and assistance during the postemergency phase, particularly FEMA, EPA, USDA, and HHS. Closely related is the failure to recognize that regulatory functions are being performed simultaneously with the emergency functions and good communications between these groups of officials is essential. - The ingestion response requires the involvement of additional response personnel who may need training in emergency response. For example, some agriculture and public health officials whose expertise is required, may not be familiar with the emergency response roles and interfaces among the various participants. The overlap and interrelationship among recovery and reentry issues that may arise during an ingestion exercise. For example, will farmers be treated as emergency workers for reentry purposes or how will this be handled? The preparation of consistent and appropriate public information. This includes the agriculture brochure issue mentioned earlier. How will information be disseminated during the postemergency phase? Has use of the Cooperative Extension System been considered? - The issue of the FEMA Exercise Evaluation Methodology (EEM). Some planners and evaluators have complained that the questions are vague and not all inclusive. Sensitivity to potential lawsuits if ingestion pathway issues are not handled timely and responsibly. (Consumers, farmers, food processors, and distributors). We have also observed the following issues being raised as major concerns during Ingestion Exposure Pathway exercises and in many cases appropriate answers and/or responses are not formulated: - Proper sampling team composition, equipment, and sampling protocol. Damage assessment of the agricultural community in both the intermediate and long term and the overall impact on the State. - Public perception within the State and adjoining States regarding tourism, agriculture, food, and restaurants, and the resulting economic impact. Reimbursement and indemnification issues. Who pays for what? How does the Price Anderson Act work and what is covered by the American Nuclear Insurers? 20 ------- Embargoes - What State agencies are responsible for initiating embargoes and who enforces them? What role do Federal agencies play? Disposal of waste - Who has the regulatory authority and responsibility for clean up and reclamation? (This is not usually addressed.) Rumor control for ingestion pathway concerns, specifically with regard to drinking milk and water and eating food. The process for determining if food products are safe. The FDA guidance dated October 22, 1982, gives response levels for only the milk pathway while setting Protective Action Guides for food in general. The draft FEMA document REP-13 gives guidance for water and non-dairy foods. The importance of harmonization in the PAGs developed for food by EPA, FDA, and FSIS cannot be overemphasized. It is also important that the States concur with the levels established by the Federal guidance. Without agreement on action levels, interstate commerce of food and milk would be seriously disrupted. This occurred in Europe following the accident at Chernobyl. Lacking harmonization, each country established their own "safe" levels. As a result, movement of foods across borders in much of Eastern and Western Europe was virtually impossible. Scenario development that provides for realistic tasking of response personnel out to 50 miles. Establishing a clear time advance from the plume phase to the ingestion phase of the exercise with sufficient time, specifically one full day, for ingestion pathway exercise play. The need for continuity, particularly during Ingestion exercises. To the extent possible, both players and evaluators should be trained and experienced. We believe that an effective approach to assisting States in planning and executing ingestion pathway exercises should include: Meetings among Federal, State, county, and utility officials 6 months to a year prior to the exercise to discuss issues to be included in ingestion exercises. This has occurred in New Jersey (Artificial Island), Pennsylvania (TMI), and Virginia (Surry and North Anna). More Federal player participation at the regional level in required exercises. Plans are being formulated for this type of participation at the Byron NPS exercise in Illinois during December 1989. Continue with the jointly sponsored USDA-FEMA Workshops which address Federal response with an emphasis on agriculture and public health issues. 21 ------- In summary, the ingestion exercises should not be viewed as being for the benefit of USD A, FEMA, or other Federal evaluators, but rather an opportunity to provide experience and training for State and local responders. Solving intermediate and long range ingestion issues for the local area should be the primary goal. Until those problems are solved, the implementation of PAGs will be extremely difficult. OBSERVATIONS CONCERNING INGESTION EXPOSURE PATHWAY EXERCISES IN-1 provides overall Ingestion Exposure Pathway guidance for: plans and ~ exercises emphasis is on three pathways: ~ milk -- other foods water Key Issues in IN-1 are: ~ Public Information ~ Protective Response -- Exercise & Drills Three key things must be demonstrated in an effective Ingestion Exposure Pathway exercise: -- The formulation of: - Preventive PARs - Actions to prevent or reduce contamination of milk and food products (continue stored feed) Emergency PARs Actions taken by public officials to isolate food to prevent its introduction into commerce and to determine whether condemnation or other disposition is appropriate Embargo - How decisions are made based on known releases, dose projections, laboratory analysis, and verification. This could be accomplished through establishing: -- Sampling priorities (milk, soil, vegetation, feed, and water) -- Mobilizing and deploying sampling teams. (Agriculture, Health and Environmental Protection) - Develop sampling plans that at a minimum describe: - How sample is received, processed, and results are forwarded to decision maker - Timeliness - System is according to State plan -- Appropriate Laboratory Support -- Labs must be active players during exercise - Operations and procedures for measuring and analyzing samples must be demonstrated - Must have good data to make decisions -- Monitoring teams must be alerted, mobilized, activated and deployed out to 50 miles (check for "hot" spots) -- Demonstrate implementation of decisions 22 ------- USDA has participated in numerous Ingestion Exposure Pathway exercises. The key recommendation my staff asked me to make was: -- Exercises are not for the benefit of USDA, FEMA or other Federal evaluators, but are to provide experience and training for State and local responders. - What issues should you be discussing to get the most out of the exercise? What would be useful to you? Big investment. Get the maximum out of it. Responders need to think in terms of intermediate and long-term solution to various and complex problems and ~ Consider what is important in local area - Hash out all the "what if issues as time permits -- Get key officials involved in the exercise play in EOC -- Keep in mind that the recovery and reentry phase will overlap the ingestion phase Based on our observations from State exercises, we believe the following issues may warrant consideration in Ingestion Exposure Pathway exercises: Dairies - Remove lactating animals from pasture and provide them with protective feed and water (everyone does this). The following are also important and sometimes overlooked. -- Interdiction of milk shipments to keep trucks out What if milk has already been picked up? What do you do with the truck? Diversion of fluid milk (if this is considered a viable option). -- Storage of dairy products. If you make the decision it is safe to use, what provisions have you made to assure the public will use it? Regulatory and Enforcement Actions ~ Quarantine eliminate agriculture products. ~ Embargo prevent the movement of products (Decisions based on facts). - Access Control Points - For agriculture products, need instructions for police as to what is expected of them. Agriculture Worker Exposure Control -- Provide dosimetry/TLDs. -- Advise farmers to wear outer clothing that covers all portions of the body, similar to what would be worn when applying pesticides. For example, gloves, boots or shoe covers and coveralls or long sleeved shirts and long pants. - Wear a protective mask or place a folded (preferably dampened) cloth over your mouth and nose when working outside to prevent inhalation of radioactive materials. -- Allow controlled re-entry into evacuated area to perform vital tasks such as milking cows or feeding livestock. - Restrict farming activities that are dust producing to prevent of contamination. Do not plant, cultivate land, or harvest. Do not move animals within close distance of house. Emergency Instructions and Public Information -- Instruct the agricultural community on exposure prevention, control and decontamination. -- Issue recommendations to restaurant operators, food transporters, distributors and processors. 23 ------- -- Advise consumers on safe products. - Public Information/News releases that are timely, coordinated, consistent, credible and reliable. Brief media in an accurate, coordinated and timely manner regarding control of contaminated food products. -- The transportation of agricultural products may be disrupted and/or rerouted -- Public perception of State and county areas and local products may be altered: GA - Vidalia Onions, WI - Dairy State, NJ- Garden State. - Key Information officials must be involved to be sure information released is timely and clear. -- Use of Cooperative Extension System. Operational Considerations -- Coordinate decisions with adjacent States (especially in regard to evacuation and traffic control) -- Decision making should be consistent among state(s)/counties. (Key point, particularly if several jurisdictions are involved.) -- Federal Support to State/local governments - When will it be requested? - Response levels - What are you using how were they derived? -- HOC staff, field & lab teams involved in ingestion measures (ability to communicate with all locations). Food and Feed Considerations Food for schools/congregate care centers/special faculties may need to be located and procured. Provide for the transport and availability of safe drinking water, food or feed. Fish and Marine Life Migratory Birds & Wild Game Fish Farms Hunting & other considerations Fresh Water Salt Water Domestic Animals & Their Products Honey Bees Decontamination -- Washing animals -- Equipment, houses, buildings and food processing establishments (Don't forget the plow and tractor in the field) How? (Firemen have been used to wash food processing plants) -- Land - options and appropriate option for the specific situation -- Don't forget to wash food and hands before eating Disposal Exposed livestock and poultry - when and how - Other contaminated product - criteria (example - truckloads of produce-lettuce, watermelons, etc. that have been interdicted) General Consequences Considerations -- Health & Social Impact -- Return - resettlement - relocation -- Psychological distress from accident (this could occur early) 24 ------- -- Demand for Social Services, such as food stamps, counseling, follow-up medical treatment, extended temporary lodging -- Environmental Impact -- Long range impact of contaminants on agriculture (may need to alternate food crops, plant fiber crops such as trees or cotton, or idle the soil) - Impact on water ponds, lakes and rivers, streams, reservoirs, (drinking water supplies and irrigation) ~ Economic Impact - Long and Short Term -- Damage Assessment to Agricultural Community Cost of lost business - restaurants, food stores & markets ~ Cost of clean-up and recovery to agriculture - Indemnification Programs -- Federal - Price Anderson Act - American Nuclear Insurers Lawsuits - Key thing is to size up cost of recovery to agriculture - immediate & long term and together develop a solution. - Political Impact -- Constraints Pressures Verification of measured levels for both preventive & emergency protective actions and a consideration of the health, economic & social impacts of such actions. Don't create a bigger problem with solutions. Scheduling Exercises - Separate day for Ingestion Exposure Pathway exercise ~ season variation (for different growing seasons) Don't schedule when adverse weather conditions (simulate) - Consider holding with adjacent State(s) when feasible - Consider feasibility of Statewide exercise when multiple plants are involved (Labor intensive for State and Federal evaluators) INGESTION PATHWAY PLAN CONSIDERATIONS Can be separate plan, part of existing plan or a separate annex (Opinion). If not integrated in plume plan, is easier to find - Be sure it is workable and doable Plan should contain as a minimum - Statement of Intent - Concept of Operation - Protective Responses State PAGs Preventive and Emergency PAR Is for milk, food, water and animal feed. Sampling plan Monitoring data and analysis - Public Information 25 ------- Rumor control Brochures Radio and TV prescripted messages -- Federal Resources Availability - Food Chain Information Annex Food establishments Milk Processors Retail foods listings Land use data More specific guidance in IN-1 26 ------- Existing Ingestion Guidance: Problems and Recommendations Robert R. Mooney Gordon L. Ziegler Donald S. Peterson Environmental Radiation Section Division of Radiation Protection State of Washington I. Introduction Washington State has been developing plans and procedures for responding to nuclear accidents since the early 1970s. A key part of this process has been formulating a method for calculating ingestion pathway concentration guides (CGs). Such a method must be both technically sound and easy to use. This process has been slow and frustrating. However, much technical headway has been made in recent years, and hopefully the experience of the State of Washington will provide useful insight to problems with the existing guidance. Several recommendations are offered on ways to deal with these problems. In January 1986, the state held an ingestion pathway exercise which required the determination of allowed concentrations of isotopes for various foods, based upon reactor source term and field data. Objectives of the exercise were not met because of the complexity of the necessary calculations. A major problem was that the allowed concentrations had to be computed for each isotope and each food group, given assumptions on the average diet. To solve problems identified during that exercise, Washington developed, by March 1986, partitioned CGs. These CGs apportioned doses from each food group for an assumed mix of radionuclides expected to result from a reactor accident. This effort was therefore in place just in time for actual use during the Chernobyl fallout episode in May 1986. This technique was refined and described in a later report (Ref. 1) and presented at the 1987 annual meeting of the Health Physics Society. Realizing the technical weaknesses which still existed and a need to simplify the numbers for decision makers, Washington State has been developing computer methods to quickly calculate, from an accident specific relative mix of isotopes, CGs which allow a single radionuclide concentration for all food groups. This latest approach allows constant CGs for different periods of time following the accident, instead of peak CGs, which are good only for a short time after the accident. Washington's new computer model is consistent with informal guidance received in 1988 from FDA (Ref. 2). An important change of philosophy made in this process was to establish CGs which define foods that may be marketed, whereas current CGs define food which must be 27 ------- interdicted. The concept of food (contaminated with radioactivity) being consumed by the public creates a totally different mindset from the concept of contaminated food being embargoed. This experience has led us to identify a number of problems with existing federal ingestion guidance, as well as some recommendations for resolving these problems. The lead federal agencies responsible for radiation protection guidance are to be commended for convening this workshop and addressing these issues. n. Problems In Using Existing Ingestion Guidance 1. The occurrence of this workshop highlights the worst problem with existing federal protective action guides (PAGs): the guidance is still not official. For over 14 years the Environmental Protection Agency (EPA) has been developing PAGs for nuclear incidents (Ref. 3). The PAG manual is still in draft form. Still existing are such basic issues as: * how many PAGs there should be for ingestion, * whether or not there should be a separate thyroid PAG, * whether PAGs should be two-tiered or one-tiered, * what time period the PAGs should cover, * what technical data is needed for implementation, * what computer models should be used, etc. 2. The guidance which exists in draft form is missing key sections. 3. Three federal agencies, EPA, FDA, and FEMA, do not agree on one set of guidance. Each agency uses different approaches and terminology, leading to conflicts for the States in trying to follow federal guidance. 4. There is no agreement on dose conversion factors (especially for the limiting infant). Those used now (Ref. 4) are outdated and do not follow ICRP 26/30 methodology (Ref. 5, 6). No lead federal agency has published dose conversion factors according to the ICRP 26/30 methodology for any isotope for the critical age group of infant. States are therefore forced to use estimates of dose conversion factors from other countries which have generated DCFs for all age groups using the ICRP methodology (Ref. 7). As an example of how serious this problem is, in units of nanoSieverts per Bequerel, the infant whole body dose conversion factors for Strontium- 90 vary from 15 (Ref. 7) to 1,270 (Ref. 4). 5. There is no agreement on diet factors for the different age groups nor agreement on the definitions of the different age groups. The NRC uses four age groups: adult, teen, child, and infant (Ref. 4). Informal FDA guidance (Ref. 2) and international guidance (Ref. 7, 8) uses three age groups: adult, child, and infant. Total diet estimates for each age group vary considerably (Ref. 4, 8-13). For example, the total average diet for an adult varies from 325 (Ref. 10) to 1689 (Ref. 13) kilograms per year, depending upon the reference. 6. No federal guidance provides for a rapid computer methodology for calculating CGs. Any set of CGs are source term dependant. Precalculated CGs tend to be overly conservative. 28 ------- Ideally CGs would be calculated soon after the accident using the actual mix of isotopes found in the environment. 7. Disagreement on thyroid doses versus whole body doses provides an unnecessary complication. The EPA draft guidance provides for a thyroid PAG 3 times higher than the whole body PAG. International guidance and informal FDA guidance provides for a thyroid PAG 10 times higher than the whole body PAG. Washington State has found that having a separate thyroid PAG severely complicates the calculation of Concentration Guides. 8. Existing federal guidance on CGs uses the peak dose model for interdictions. There are several serious problems with this interdiction model. Two of the biggest ones are: a. Peak CGs are good for only the very short term, say the first day of the accident After the first day, decay curves must be used for each isotope, or the public will be overexposed if the same CGs are used for successive days and weeks after the accident. Peak CGs raise questions as how to market interdicted foodstuffs as the radioactivity decays. There are serious difficulties in establishing relaxation levels. Because of the decay and weathering assumptions inherent in a peak CG, the appropriate relaxation levels would decrease with time. This results in serious inequities between producers inside the restricted area versus those outside the restricted area. b. Existing peak CGs are made unnecessarily complicated and inconsistent by the use of weathering terms. Both decay and weathering are considered to find the very peak that could be allowed at the time of the accident, which, if decayed and weathered down with time, will give the person the applicable PAG. Produce is not corrected for weathering, whereas leafy vegetables are. Therefore leafy vegetables are allowed a higher peak CG than produce. How can the difference be explained to a reporter or the general public? 9. Federal ingestion guidance has yet to incorporate the lessons learned from the Chernobyl experience (Ref. 2). 10. The two-tiered PAG system (preventive and emergency) is confusing, inconvenient, and unnecessarily complex. The above points are just some of the problems Washington has experienced in trying to implement existing federal guidance. Below we offer several recommendations for resolving these problems. III. Recommendations The following recommendations are based on the underlying precept that implementation of the PAGs should be as simple as possible. This is particularly important since the decision- making process must be understandable and usable to those from various responding state and federal agencies as well as the general public. These groups will seldom have technical backgrounds. 29 ------- 1. Establish a maximum allowable dose (PAG) for the ingestion pathway. 2. State the ingestion PAG as a single value, not as a range of values. For political reasons, the States are forced to use the lowest number in the range anyway. 3. Discontinue the thyroid PAG and go solely with a committed effective dose equivalent PAG. Considering the uncertainties between health effects and the dose associated with these low levels of radiation exposure, the thyroid dose savings from a separate thyroid PAG does not merit the added complexity in computations and decision making. With little added health risk, the calculations and decision making are made much simpler. 4. For simplicity of computation and administration, it would be prudent to have first year PAGs only. Planning should only occur for the first year. 5. Develop only one PAG for ingestion (both food and water), not a separate PAG for drinking water. 6. Have the same PAG apply to home grown produce as well as commercially marketed foodstuffs. 7. Special categories of food, such as herbs and spices, should be allowed 10 times the concentration of food and water. 8. Special populations, such as hospitals, prisons, schools, etc., should have the same (and not higher) ingestion PAGs as the general public. 9. Aim for maximum cooperation with international agencies to have uniform guidance with all countries. Since the Chernobyl accident, the State of Washington has issued 47 certificates required to export state food products out of the U.S. If the U.S. federal guidance is not in harmony with international guidance, U.S. food exports may suffer. 10. The lead federal agencies should leave this workshop with a commitment to establish common dose conversion factors by September 1990. These dose conversion factors must include the infant since that age group becomes a limiting factor. 11. The lead federal agencies should establish common total average diet mass per year per individual (at least for the limiting infant) by September 1990. This includes water as well as food. The average meat, cereal, fruit, and produce diets for a one year old infant are not zero (Ref. 13). Several early diet estimates of infants listed only milk and water (Ref. 4). The lead federal agencies should not make this same mistake in arriving at new unified diet factors. If a separate PAG is adopted for water or for any other diet fraction, then the diets must be broken down by pathway. 12. To avoid problems with weathering terms, and to obtain CGs that are good for a specific period of time following an accident, constant (straight-line) CGs should be calculated instead of peak CGs. When the constant CGs are partitioned according to isotope, the weathering 30 ------- terms disappear as variables in the calculations. Only physical decay matters in the relative mix of isotopes (assuming all isotopes weather equally). 13. EPA, FDA, FEMA, and USDA should go beyond PAG guidance. They should propose uniform Concentration Guides. Or, they should develop a single computer code to calculate CGs from the actual mixes of isotopes found in the environment following the accident 14. Uniform Concentration Guides and/or the computer code should incorporate the post- Chernobyl international guidance (see Ref. 2). 15. States with experience in ingestion CG modeling should have input to the federal formulation of the PAGs and associated computer codes. 16. The PAGs and associated computer code(s) should be officially proposed in the Federal Register by September 1990. 17. The PAGs and associated computer code(s) should be finally adopted by September 1991. The State of Washington hopes these recommendations are useful and will be considered and adopted. They are offered to correct and simplify existing technical problems with federal guidance which is neither definitive nor official. Any guidance for the ingestion pathway should adhere to the following principles: * it should be technically sound but as simple as possible so decision-makers and the public understand the process. * it should not be stymied by technical differences which, in the larger picture are quite minor (e.g. what should the thyroid to whole body ratio be?) compared with large uncertainties which already exist (e.g. uncertainties in dose/response, dose projection modeling). * there needs to be a commitment by the lead federal agencies to generate, with state input, a comprehensive, consistent and coherent set of guidelines which has been lacking for so long. * this commitment must be given high priority so that the aggressive schedule proposed above is met. 31 ------- REFERENCES 1. ZffiGLER, G; JEFFERIES, A.; PETERSON, D.; MOONEY, R.; MOHSENI, A. Draft recommendations for ingestion pathway response levels for radiation accidents. Department of Social and Health Services. Office of Radiation Protection. November 14, 1986. Olympia, Washington. 2. SCHMIDT, G. Impact of Chernobyl on ingestion pathway guidance. Center for Devices and Radiological Health. Food and Drug Administration. May 1988. Washington, D.C. 3. ENVIRONMENTAL PROTECTION AGENCY. Office of Radiation Programs. Environmental Analysis Division. Manual of protective action guides and protective actions for nuclear incidents. EPA-520/1 -75-001. September 1975. Washington, D.C. 4. U.S. NUCLEAR REGULATORY COMMISSION. Calculation of annual doses to man from routine releases of reactor effluents for the purpose of evaluating compliance with 10 CFR part 50, Appendix I. Regulatory Guide 1.109, Revision 1.1977. Washington, D.C.: U.S. Government Printing Office. 5. INTERNATIONAL COMMISSION ON RADIATION PROTECTION. Recommendations of the international commission on radiological protection. ICRP Publication 26. Annals of the ICRP. Volume I, No. 3. 1977. Oxford: Pergamon Press. 6. INTERNATIONAL COMMISSION ON RADIATION PROTECTION. Limits for intakes of radionuclides by workers. ICRP Publication 30. Annals of ICRP. Volumes 2-8, 1979- 1982. Oxford: Pergamon Press. 7. NATIONAL RADIOLOGICAL PROTECTION BOARD. Committed doses to selected organs and committed effective doses from intakes of radionuclides. NRPB-GS7. August 1987. Chilton, Didcot, Oxfordshire, England. 8. INTERNATIONAL ATOMIC ENERGY AGENCY. Derived intervention levels for application in controlling radiation doses to the public in the event of a nuclear accident or radiological emergency. Safety Series No. 81. 1986. p. 63. Vienna: IAEA 9. WORLD HEALTH ORGANIZATION-GENEVA. Derived intervention levels for radionuclides in food. Guidelines for application after widespread radioactive contamination resulting from a major radiation accident. 1988. Albany, NY: WHO Publications Center. 10. UNITED STATES DEPARTMENT OF AGRICULTURE. Nationwide Food Consumption Survey-Continuing Survey of Food Intakes by Individuals. Low-income women 19-50 years and their children 1-5 years, 1 day. NFCS CSFTI Report No. 85-2. 1985. 11. U.S. DEPARTMENT OF HEALTH EDUCATION AND WELFARE. Public Health Service. Radiological Health Handbook. Revised Edition. January 1970. p.216-217. Washington, D.C. Government Printing Office. 32 ------- 12. NUCLEON LECTERN ASSOCIATES. The Health Physics and Radiological Health Handbook. 1984. p. 208. Olney, MD. 13. U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES. Public Health Service. Bureau of Radiological Health. Background for protective action recommendations: Accidental radioactive contamination of food and animal feeds. HHS Publication FDA 82- 81%. August 1982. Rockville, MD: U.S. Government Printing Office. 33 ------- Concerns for the Human Element in Implementing Protective Action Guidelines (PAGs) Aby Mohseni Aileen Jeffries Paul Fedorchak Department of Health Reactor Safety Section State of Washington Introduction Washington State has tested implementation of current ingestion PAGs at several drills and exercises. This testing has shown that protective action decisions cannot be based on computed projected doses (due to many assumptions involved). And so we recommend an alternative, simpler methodology based on the concentration of radionuclides in foods. Simplifying the process helps us to avoid confusing the public and to avoid problems that foster unintended public response. The purpose of the present paper is to describe three such problems, propose tentative solutions, and request federal assistance in arriving at a final resolution. The problems are as follows: Following a known release of radioactive material from a nuclear plant... 1) Should we prevent food from reaching the market until its safety can be determined or allow food into the market until its danger is verified? 2) Should a decision to prevent food from reaching the market be based on plant status (coupled with limited environmental measurements) alone or should it await laboratory analysis of samples taken after the release? 3) Should we continue using the current two-tier (Preventive - Emergency) PAG structure or abandon it in favor of a system which replaces the PAG concept with a simpler Allowable Concentration Level (ACL) system? The first problem is the main issue of the present paper, with the other two being more accurately characterized as subsets of that problem. A background summary is presented below, along with our solutions. 35 ------- Background Following Chernobyl, there was widespread loss of control over food management in Europe. This situation, characterized as chaotic (1), focused world attention on the need to develop better guidance, and resulted in more resources being made available to the responsible federal agencies. Recently, numerous drills at nuclear power plants, in addition to the Chernobyl disaster have raised concerns about the "human element" involved in the implementation of ingestion PAGs. During an emergency, people need to believe they can control their exposure to potential danger. Fostering this sense of control is the single most important issue in preventing panic and ensuring cooperation of the general public. To this end, the importance of consistency amongst various state, local and federal officials cannot be overemphasized. If the decision makers from various jurisdictions are not clear, decisive and responsive enough, in terms of telling people what they need to do to ensure safety, public confidence in their ability to handle the crisis may be severely hampered. Faced with mixed messages, the public will be likely to act in the most conservative way, and this could cause large unnecessary economic losses. For this reason, compromises and reasonable simplifications in the developrnen of the PAGs and other guidance should be made in order to achieve consistency. The guidance should be technically sound, simple to follow, and leave little room for on-the-spot interpretations that could undermine consistency. Yet at the same time, it cannot be so specific as to be impossible to implement It has been observed that when faced with confusing and unimplementable guidance, there is a tendency for public officials to overreact. This would be especially true when it comes to radiation. Unfortunately, during crises, leaders often emerge into the spotlight by proving their commitment to their citizenry's welfare through concerned (over)reaction. Statement of the Main Problem Last fall, during extensive two-day exercises, we identified the following conflicting "human" elements that must be addressed when formulating PAGs: maintaining public confidence that the market place has uncontaminated food - maintaining the confidence of the agricultural sector that the state will act to minimize their economic losses. The conflicting nature of the above elements came to light during a drill at WNP-2. Below is a description of the issue, and our preferred solution to it. There are no precedents for this situation; however, two incidents in the Northwest last year - The Alar Scare and Exxon Oil Spill provide some insight into the implications of the alternative solutions presented below. 36 ------- Policy Issue following Reactor Accidents The scenario for a drill at WNP-2 involved a severe accident at a nuclear reactor that released a large quantity of radioactive material to the environment through an airborne plume. This material was deposited on the ground as the plume passed over and caused agricultural areas below the path of the plume to be contaminated. The area of contamination was determined from computer models which estimated the path of the plume and from ground measurements of radioactive contamination made by field teams. The State policy maintains that to assure public health is protected, it is necessary to embargo crops from all areas suspected of contamination until laboratory results of crop samples are available to demonstrate that the crops are not contaminated, or contamination is below allowable limits. An alternative policy advocated by a federal agency is to not embargo any crops until laboratory results are available to prove that the crops are contaminated beyond the allowable limits. The reason for this action is argued to be that a State embargo of crops from a large suspected area may cause large unnecessary economic losses. The embargoed crops are delayed in their access to market and thus lose all or part of their value. The State may be held liable for these losses. The argument continues that the intervention levels are ultra-conservative, and that the levels of radioactive contamination at which the crops are excluded from commerce would represent only a small health hazard if consumed for several days following an accident. Thus, if an individual were to consume a few contaminated items for the short period of time following the accident before laboratory results were available, the health effect would be insignificant. The Washington State policy maintains that we cannot, even for short duration, allow foods contaminated above federal guideline levels into the marketplace for the following reasons. First, public health and safety must have the highest priority above considerations of economic liability. Second, economic losses from a limited, temporary embargo would not be excessive. Third and finally, the economic consequences of not enforcing a precautionary embargo would be much graver and more far reaching than the alternative, as the appearance of a few contaminated agricultural products in the market could cause consumers to panic and refuse to buy any Washington State products. The basis for these three arguments is developed below. 1. Public health is the priority. The protection of the public health and safety is the prime mandate of the public health officials. No policy which places public health and safety as a secondary factor is acceptable. If untested and contaminated food goes to the market it might have any level of contamination. Hot spots within a deposition area may have contamination tens of times higher than the allowed levels. Were the State to release foods potentially contaminated beyond the intervention level, not only would the health effects have to be accounted for, but it could also result in a severe loss of public confidence and trust. 2. Immediate embargo costs are not excessive. 37 ------- The alternative policy argues that costs of embargo could amount to billions of dollars. In fact, the costs for holding crops 48 hours in an agriculturally rich area as Eastern Washington are probably less than $100,000. An upper limit for the losses resulting from holding the agricultural products indicated in the drill scenario would be $260,000. In the context of a multibillion dollar reactor accident, these costs are not excessive. (These costs are derived from data provide by the Yakima and Grant County extension agents, and staff from the Washington State Department of Agriculture). 3. Public values safe agricultural products. The public is extremely sensitive to contamination by radioactive material. If the public suspected that Washington food was contaminated, all Washington products would suffer. It would take years to re-establish credibility in the State's agriculture. The situation could cause a market panic that would cost far more than the proposed embargo. Where the public is concerned, the perception of safety is just as important as the actual safety. That is, not only must we ensure safety, we must also ensure the public's belief in it. Any waivering by the state will cause the public and agricultural sector to doubt their authority. As public officials, we may find ourselves in the very difficult position of trying to make reasonable judgements that are not overly conservative, in the face of heightened public sensitivity. Public Reaction to Alar in Apples For an excellent precedent of what can happen when the public is given a reason to suspect the safety of food in the marketplace we have only to recall the recent "Alar scare." In the Alar case, the public was "informed" by the popular television show 60 Minutes that apple growers were still using a chemical Alar - on their apples even though it was known to cause cancer in children. Within days we learned that the "evidence" for the alleged cancer link was provided by a study that had already been identified by the scientific community as being seriously flawed. And in the weeks to follow, hundreds of scientists came out supporting Alar's safety, and criticizing the way the danger had been misrepresented by the media. But all this was lost on the public. Equating Alar with cancer, they stopped buying apple products. Apple growers, unable to wait for the scientific message to trickle through the buying public, acted to cut their losses by announcing that they would no longer use Alar. Although this action was a marketing strategy, the public took it as an admission of guilt; an acknowledgement that Alar was indeed dangerous. And who could blame them. Faced with conflicting information, it was better to err on the side of safety. Err on the side of safety is what the public will do if contaminated food is discovered in Washington's markets. With Alar, even as the danger itself was being scientifically refuted, the public still pulled away. With radioactive contamination, we won't even have that luxury. The economic impact of a "few contaminated food items" could quickly snowball. Besides the direct costs of a turn away from Washington food products, there would be the costs of mass testing for 38 ------- contamination, the legal liability to individuals and fanners, and ambiguous health effects. The phrase "Grown in Washington" would take on a whole new meaning. The main difference between the two above-stated positions can be summed up in the following way. The federal agency is worried about immediate, direct economic losses from a "precautionary" food embargo, while the State's concerns focus on the more long-term consequences associated with the loss of trust in Washington's food products and its public officials, if contaminated food was discovered in the marketplace. Alaska, wrestling with similar immediate versus long-term consequences in the wake of the Exxon oil spill, adopted a "zero tolerance" policy to keep fish contaminated or even suspected of contamination from reaching the market. Although one would expect this decision to anger the fishermen, it appears that they are generally supportive of it. The (zero tolerance) policy has the support of most fishermen, who believe it would be better to lose an entire season than to have the market crash and cost them their livelihoods for several years." (2). Satellite Issues At the present time a two-tiered system is used for ingestion Protective Actions: Preventive PAGs and Emergency PAGs. This structure requires a fairly complicated decision process. The concept of PAG, namely projecting the dose to the public from the ingestion of contaminated food and using this as the criterion to intervene, has not proven to be practical. Variability of such parameters as the public diet, dose conversion factors and source terms, does not allow consistency and uniformity of decisions during accidents. The decision process could be made simpler. The triggering event could be better defined; and the contamination levels could be made more acceptable to the public. A one-tiered allowable concentration level structure should be adopted instead of the current PAG concept. Contamination levels, sanctioned by the FDA, should be set as with other food contaminants, such as pesticides or other chemicals, at allowed concentration levels (ACL's). These levels should apply to any radioactive contamination, at any time, resulting from any accidental occurrence. They should be conservatively calculated to eliminate the need for additivity due to contamination by more than one radionuclide. Accident Scenario and Recommendations The immediate state and local response to a severe reactor accident will set the tone for public confidence in what follows. If one postulates a severe reactor accident, the immediate response would focus on protecting the public from exposure to the plume. The regulatory position for this phase has been shifting towards making protective actions based primarily on plant status; partly because of the urgency present in the plume phase and partly due to uncertainties associated with dose projection techniques. Parameters such as the reactor vessel water level, reactor coolant system pressure and temperature, radiation levels inside containment and containment status will drive the offsite protective actions. The field measurements will be used 39 ------- to confirm or deny the presence of radionuclides, and help characterize their release and atmospheric dispersion. During the plume phase, plant parameters coupled with offsite measurements should determine the magnitude of noble gases in the release and detect the presence of the radio-iodines and the radio-cesiums. Even in the absence of the urgency inherent in the plume phase, this information could and should be used as soon as it becomes available, to determine ingestion protective actions intended to prevent or reduce the contamination of foodstuff, e.g., placing cattle on stored feed. This action should not await laboratory analysis results confirming the contamination of pasture beyond the preventive PAGs. In fact there may be no need for a preventive PAG at this phase; a two-tiered PAG system is too complicated and unnecessary. The fact that a nuclear plant has experienced an accident of sufficient severity to be classified as a General Emergency coupled with valid plant information that the release is either unfiltered or unmonitored should be enough to warrant protective measures intended to reduce or prevent the contamination of foodstuff. Computerized atmospheric dispersion models can be used to project deposition of radionuclides. Harvestable crops in areas where projected deposition levels equal or exceed the allowable limits should be embargoed. In other words, when a General Emergency is dec'..red at a plant and there is reason to suspect that radio-iodines and other particulates may have been released into the environment, agricultural products potentially contaminated should not be allowed into the market place until an adequate sampling system and laboratory analysis sufficiently characterize the deposition and radio-nuclide concentrations in those products. As noted earlier, an "allowable concentration level" (ACL), rather than an emergency PAG, should become the criterion for retaining or lifting the protective embargo. The embargo can be lifted, modified or continued when an adequate sampling program sufficiently characterizes the radionuclide concentrations in the embargoed crops; this leads to another issue, namely the statistical significance and the adequacy of the sampling program. There are currently no federal guidelines on the statistical requirements and sampling program adequacy for the States to follow. As a result, major decisions have sometimes been made by public officials during federal evaluated drills without the use of sound and comprehensive sampling criteria. Federal guidance is needed in this area so that the sampling criteria used by different States and jurisdictions to impose or relax ingestion protective actions are compatible. Federal guidance to the State and local governments should include statistical analysis requirements, sampling methodologies and strategies, sample counting and levels of precision. Recommendations Based on the above the following specific recommendations are made for severe reactor accidents: 1. To eliminate the confusing Preventive PAG in a two-tier system the following Protective Actions should be taken based on plant conditions. These actions will ensure that no contaminated food products reach the market. 40 ------- Embargo harvestable crops in a potentially contaminated area until an adequate and statistically sound sampling program characterizes the radionuclide concentrations in those crops. This action could be tied to the declaration of a General Emergency and confirmation of an unmonitored or unfiltered release. Place cattle on stored feed at General Emergency outside the 10 mile Emergency Planning Zone in areas expected to be contaminated. No such actions are recommended within the 10 mile zone until the threat to the pubb'c from plume exposure is removed. 2. To move away from the PAG concept to a more practical decision-making tool that can be used in any radioactively contaminated food (regardless of source), and to ensure consistency among all jurisdictions, we should adopt a one-tier allowable concentration level (ACL) system. These ACLs should be developed for food and water by radio- nuclide based on the acceptable risk concept. The presence of radio-nuclides below these levels in food products would constitute an acceptable public dose. This would be a set of fixed (non-peak) regulatory levels which would permit marketing. The contamination of food products by radioactive material should not be treated any differently from chemical contaminants such as pesticides. The selection of these ACLs should no longer be based on the assumption that a severe reactor accident will not occur more than once in a lifetime (3). Once a set of ACLs are developed, public officials should move away from expressing PAGs or projected doses, and instead focus on allowed concentration limits. 3. Assumptions used in the calculation of these ACLs should be conservative enough to avoid the need for additivity due to contamination by more than one radionuclide. (A reasonable number would be to calculate the ACLs to correspond to 1 mSv (0.1 rem) per critical isotope.) 4. Expand the list of isotopes of concern (currently light-water-reactor source term dependent) to include weapons accident source terms, i.e., Pu isotopes. 5. Federal guidance to the State and local governments should include statistical analysis requirements, sampling methodologies and strategies, sample counting and levels of precision. REFERENCES 1. SCHMIDT, G.D. Impact of Chernobyl on Ingestion Pathway Guidance, Aug 1988. 2. BORRELLI, Troubled Waters, The Amicus Journal, 11(3), pg 14, Summer 1989. 3. 47FR47073, Oct 1982. 41 ------- Problems Related to Public Perceptions of Radiological Emergency Planning and Response Margaret A. Reilly Pennsylvania DER/Bureau of Radiation Protection To the best of my knowledge, no organized scientific study has been made of the basis for public fears surrounding radiation accidents or of radiation in general. This presentation makes no pretence of being such. What is offered here should be construed as food for thought or perhaps a light snack. Over the last 15 years a few opportunities for observation of public reaction to radiation crises have presented themselves in Pennsylvania. These events were the fallout of Chinese weapon test debris in the fall of 1976, the accident at Three Mile Island in March of 1979, and the accident at Chernobyl in April of 1986. The whole problem really began in 1945. In early August of 1945, the atomic age was born into public perception, literally in a blaze of glory, with the detonation of a nuclear weapon at Hiroshima. That spectacular start, followed by a decade of veiled secrecy surrounding weapons technology and surrounding the infancy of the peaceful uses of atomic energy, worked wonders to instill a sense of fear and suspicion in the mind of the public. Although historically warfare has been largely responsible for driving technology, the nuclear branch on the tree of technology probably took a different twist. It would be handy if radiation smelled bad. Then we would not have the public perception problem. Of course we would all be doing something else for a living anyway. A really fundamental problem here is the matter that the average individual cannot gather his own information with which to make a decision, radiation being undetectable by the human senses. He must generally depend on a faceless bureaucrat to tell him what to do. He has, in effect, surrendered control to somebody he doesn't know. Control is right up there after air, water, food and shelter in human priorities. This would seem to suggest that if the bureaucrat were endowed with a face, that some element of trust would ensue. This appears to be the case, witness the success of Harold Denton of USNRC as the single spokesman during the accident at Three Mile Island. The case may, however, not be universally true. There is reason to suspect that the spokesman must be someone that the individual doesn't know personally, a prophet from another village. That side of the coin goes something like this: I, as an ordinary person, don't know anything about radiation. You are my friend or relative or neighbor or coworker, and you are a lot like me. You don't know 43 ------- anything about radiation, either. Nobody knows. But if you do know, it must be because you are in league with the industry. Come to think of it, you do talk a lot like THEM. This knowledge aspect of the problem has a few corollaries. One is the notion that, after all, this judgement is being made by a government worker, and we all know that those folks are ignorant. No one in his right mind would cede control to a government worker. (This is especially true in government towns where many people are government workers, who know how government workers are.) Another knowledge corollary is found among technical professionals who are not radiation specialists. If the average radiation specialist were to think back to their high school and college science courses which were not specifically radiation oriented courses, in few, if any instances, did the course work ever get around to the radiation and radioactivity chapter in the back of the book. So one frequently encounters technical professionals who feel compelled to express views on radiation issues in a convincing way in the eyes of the non-technocrat, while never having made it to the back of the book. After all, if someone is a chemist, physicist, engineer, or physician, he should know about this. In the specific case of foodborne radioactive contamination two public per,,sption phenomena have been observed to date. The first is the perceived relative radiotoxicity of domestic versus imported contamination. The ratio appears to approximate ten to one, domestic to imported. The value could be higher than that. Far more concern was expressed over an intermittent 20 or so pCi/liter 1-131 in milk from a few close farms after the accident at TMI, than concern over widespread contamination to 1000 pCi/liter throughout the northeast United States after the Chinese episode in 1976. The same comparison holds for public response to the accident at Chernobyl in 1986. This resulted in widespread milk contamination up to 50 pCi/liter over a two week period, at least in Pennsylvania. Two possible reasons for this perception have been identified. One reason could be the ease of avoidance of a local problem such as was encountered at TMI. As the sign in the Safeway in Bethesda said: "We don't sell Pennsylvania milk". It would be a bit much to believe such a sign for the weeks following the Chinese episode or Chernobyl, which would then have to read: "We don't sell northern hemisphere milk". The other possible reason for this relative toxicity ratio is something akin to the old control problem. If the problem is from "over there", there is not much that the government could do about it. On the other hand, if the problem is from "over here", somebody allowed it to happen; the utility and government being the somebodies. In this case it is a lot easier to get the ear of the somebodies. The second public perception phenomenon relating to foodborne contamination is the relative toxicity ratio between uptake resulting from ingestion versus uptake resulting from inhalation. It appears that ingestion is the greater concern. This may have something to do with control, again, in that it regardless of one's confidence in the faceless bureaucrat, one can choose not to consume suspect commodities. Choosing not to breathe is less an option. In the course of the accident at Three Mile Island a major fraction of the population from the surrounding area engaged in a voluntary spontaneous evacuation. This was in spite of the fact that an evacuation of the general public was never recommended or ordered. People did not seem 44 ------- to care whether they lived downwind or not; they just left. This observation coupled with actual wind conditions on the first day gave rise to a revised philosophy of protective action implementation in Pennsylvania. During the first day of the accident the wind direction changed from 30 degrees to 270 degrees. Since downwind could, in effect, be everywhere, and people were very likely to leave regardless of where the affected area was, the policy of a 360 degree protective action area was established, extending out to 10 miles. (If everyone is going to leave anyway, it is best we plan around that.) The policy remains in effect. The basis for the spontaneous evacuation probably include a large dose of control, i.e. since I can't independently assess the problem for myself, I can at least control my risk by getting out of the area. The situation was exacerbated by the dearth of information from sources perceived to be reliable. In this case no news was bad news. In addition many people evacuated because they expected that a forced evacuation would be ordered and they wanted to beat the rush. Another public perception which prevails in times of normal operations as well as during radiation crises is that of unlimited government resources to meet their individual demands. One area perceived to be inexhaustible is that of field monitoring capability combined with radioanalytic capacity. This notion is frequently shared by people in high places in government especially from agencies which are not charged with doing the monitoring. It is also shared by the news media. People will demand that specific data be available for their county or town or neighborhood, yea verily for their house; even if their house is at the other end of the state. After all, if measurements were not taken there, "nobody knows if the plume didn't sneak over there". People will want the contents of their swimming pool analyzed. High ranking government officials will have beef livers, broilers, eggs and other non-traditional things sent to the lab for analysis. Federal agencies will call at two in the morning looking for updated milk data, evidently with the expectation that cows should be milked every four hours, or perhaps that a catheter be installed with a line running from utter to analyzer. This perception of inexhaustible sampling and analytic capacity can be addressed up front by stipulating in the plan the agency which will control this function. Another enormous help can be the data from an extensive inplace environmental monitoring program, especially with respect to TLDs. Some of the public and news media demand can probably be eliminated by early and frequent news releases covering the extent of monitoring and the results. It is important to include a representative sampling from areas known not to have been visited by the plume. Negative data is at least as valuable as positive data. The important thing here is to portray that "somebody knows". CONCLUSIONS To be forewarned is to be forearmed. Some of the observations presented here are probably right and some are probably wrong. Radiation crises being the rare occurrences they are, we do not have the data base for generating scholarly quantitative reports. Suffice it to say, however, that one should be prepared for people to behave in what they believe to be their own best interests; to keep control of their lives. The more information they have upon which to base their decision, the better. The information must be accurate and, above all, timely. The information should be delivered by a single spokesman of high perceived credibility. To do this 45 ------- requires a high degree of organization in the responsible agency in the planning, operating and control of the response effort. 46 ------- The Role of the United States Food Safety and Inspection Service After the Chernobyl Accident Ronald E. Engel Victor Randecker Wesley Johnson Food Safety and Inspection Service United States Department of Agriculture The Food Safety and Inspection Service (FSIS) of the United States Department of Agriculture (USDA) inspects domestic and imported meat and poultry food products to assure the public that they are safe, wholesome, not economically adulterated and properly labeled. The Service also monitors the activities of meat and poultry plants and related activities in allied industries, and establishes standards and approves labels for meat and poultry products. As part of its responsibility, shortly after the Chernobyl accident occurred, FSIS developed a plan to assess this accident's impact on domestically produced and imported meat and poultry. The events leading to the accident at the Chernobyl plant began on Friday morning, April 25, 1986, entered a stage of crisis with an explosion at 1:23 a.m. on April 26, and over the subsequent week to 10 days released the largest quantity of radioactive material ever freed in one technological accident [1]. The distribution of radioactive materials from Chernobyl occurred in the following manner [2]: After 2 days the lower-level particles (surface to 1.5 km) moved towards Scandinavia. After 4 days the lower-level cloud was still over Scandinavia with parts moving into Western Europe. Mid-level (1.5 4.5 km) was moving toward the Mid-East and upper level (4.5 - 8 km) was moving toward Siberia. After 6 days the upper-level cloud was approaching Japan. After 10 days part of the upper-level cloud was over the U.S. The Chernobyl fallout was transmitted through the troposphere, and fell out in a relatively short period. In contrast, the bulk of weapons testing fallout came down through the stratosphere, where aerosols have residence times of 1 to 5 years [1]. 47 ------- The accident at Chernobyl demonstrated that accidental releases of radioactive substances into the environment can contaminate large geographical areas. The possibility, although improbable, of future accidental releases cannot be ruled out; therefore it is incumbent on the international community to be prepared to measure environmental radioactivity in the event of an accident. One aspect of being prepared after any nuclear accident where radioactivity is released into the environment, public health authorities must introduce measures to restrict the radiation doses received by members of the public to minimize the risks of adverse effects. Measures must be taken to minimize the incorporation of radionuclides into food produced in areas where there is ground contamination. Control measures over food could exist for months or even years. In addition to the predicted physical health consequences of irradiation, considerable psychological effects may constitute a significant public health and political problem. The level .of anxiety generated by the possible contamination of food or the environment may not be related to the level of exposure. Psychological stress or even hysteria may be exhibited where radiation is low or insignificant. These effects can be attributed to: 1. The association of nuclear accidents with the explosion of a nuclear bomb; 2. The inability of the human senses to detect ionizing radiation; and 3. Inadequate and often conflicting information concerning the accident. A^equate planning for dealing with the potential emotional and psychological problems is an essential component of emergency preparedness [3]. Most authorities agree that the single most important aspect of emergency response is the communication system. Experience has shown that when any major accident occurs - not just those involving radioactivity - the normal communication system is usually not adequate, and therefore a reliable, alternative system of communication for emergencies will be needed and must be available. [3] An advisory group of multidisciplinary technical experts, which is organized in advance can make decisions and communicate with local professionals to substantially minimize radiation contamination of populations and their food, feed, and water supplies. Pre-planned communications will enhance evaluations of the exposure pathways during all three phases of a nuclear accident to more adequately apply the proper protective measures. In evaluating any disaster situation, including those involving radiation and radioactive materials, it is important to place the specific situation in perspective to other risks. Actions taken to control radioactively contaminated foods should be appropriate to the likely risk. Special care must be taken to assure that counter-measures do not result in new and greater risks. If certain food products are to be removed from the market because of low level radioactive contamination e.g., well within the safe standards established by the international community, it is important that the nutritional status of the population is not thereby compromised. Although preliminary monitoring results will become available soon after an accident, they will be difficult to evaluate fully. Initially, monitoring will be directed towards identifying higher levels of contamination in order to specify areas in which further countermeasures will need to be considered. It is important for monitoring to be undertaken well outside the areas of concern to provide data to the responsible authorities to take the appropriate actions. 48 ------- Three phases of a nuclear accident have been identified. The early, intermediate, and late or recovery phases are generally accepted as being common to all nuclear accident scenarios. Although these phases cannot be represented by precise periods, and may overlap, they provide a useful framework within which one can intervene with countermeasures. The actual countermeasures used in a specific situation depend on the level of radioactive contamination, the availability of radionuclides in the contamination, and intervention levels used for the different food products. Derived intervention levels can be determined (once intervention levels of dose have been set) from knowledge of physiological and metabolic processes in human beings, of the distribution of radionuclides in the body after intake, and of the resulting radiation doses to various body organs [4]. After the Chernobyl accident FSIS and the Food and Drug Administration (FDA) met to establish intervention levels for food, because derived intervention levels for meat and poultry in the United States had never been officially adopted. The FSIS derived intervention levels for meat and poultry were established by using the FDA's "Accidental Radioactive Contamination of Human Food and Animal Feeds; Recommendations for State and Local Agencies" [5]. At that time, FSIS and FDA agreed that meat and poultry could be separated from food items under FDA's regulatory control with respect to potential food contamination from the radioactive fallout. Meat and poultry composed a readily discernible and easily segregated subset of all food items. The radionuclide intervention levels that were established were based on a 5 mSv projected dose commitment to the whole body, bone marrow, or any organ other than the thyroid. This intervention level was based, in part, upon the expectation that the major contributors of radiation to imported meat and poultry will be cesium-134 (half-life of 2.1 years) and cesium-137 (half-life of 30 years). In addition, it was not expected that iodine-131 (half-life of 8 days) would contribute radioactive levels of any practical concern. The calculation of the intervention level took into consideration the total intake of activity from radionuclides and the average daily consumption of meat and poultry. In calculating this response level, FSIS used data for U.S. consumption of meat and poultry which represented 13 percent of total food intake. Other derived intervention levels, such as the one developed by WHO, use the total average daily consumption of all foods [4]. This information was not available to FSIS at the time of the accident. On May 16, 1986, FSIS officially set a total cesium (cesium-134 plus cesium-137) intervention level of 2,775 Becquerels per kilogram (Bq/kg) and 56 Bq/kg of iodine-131 for meat and poultry. On May 28, 1986, FSIS began collecting samples of meat and poultry products imported into the U.S. from 14 European countries. The criteria for selecting samples included the best available information concerning the geographic distribution of the fallout, types of products being imported and the level of contamination of the products as determined by scintillation survey instruments used by FSIS inspectors at the seven ports of entry. The samples were collected in response to significant readings on the instruments and subsequently sent to the laboratory. Initially, the following five radionuclides were measured in the laboratory. Cesium-134, Cesium-137, Strontium-89, Strontium-90, and Iodine-131. By October of 1986, 366 of 815 samples exceeded background levels for total cesium. Iodine and strontium results were not practically distinguishable from background radiation levels. However, only, five countries had any samples with results greater than 37 Bq/kg for total cesium: 49 ------- Belgium, Hungary, Poland, Romania, and Sweden. Only Romania had values greater than 185 Bq/kg, with the highest reading of 794 Bq/kg. The sample data collected and information on agricultural practices in the exporting countries indicated that the occurrence of these two cesium radionuclides in meat and poultry may continue for an extended period. Six months following the release of radioactivity, FSIS determined that the intervention level of 2,775 Bq/kg needed to be reassessed. The FDA 1982 guidelines are for short-term protective actions in an accident resulting in radioactive contamination of human food or animal feeds, and not for long-term, continuous exposure applications [5]. They state that the duration of the recommended protective actions should not exceed 1 or 2 months. However, evaluating the public health consequences of food contamination, even on a preliminary basis, requires a period of some length following the accident to assess or reassess all the available pertinent information. These protective action guides consider the types of contamination which might occur after such an event, the half-lives of resulting radioactive substances, and the biological pathways for human exposure. The FSIS initial intervention level of 2,775 Bq/kg for total cesium was established at one-tenth of the emergency Protective Action Guides (PAGs) [5]. in specific situations, and where justified, lower projected doses than the PAGs can be established. Another \nportant consideration in establishing the FSIS intervention level was that the FDA guidelines did not consider perceived risks in developing the PAG values. Such risks involve a high degree of subjectivity and could cast doubt on the validity of the scientific evaluations. In the opinion of FSIS, protective actions had to address the nature of the situation, the availability of resources, and the impact of these actions. The FDA guidelines provided FSIS, by virtue of its immediate knowledge of its operations, the basis for developing intervention levels to meet the particular needs of the Agency. Therefore FSIS determined that the initial intervention level of 2775 Bq/kg needed to be lowered to meet the criteria of good public health practices. Since the 2775 Bq/kg intervention level was established using the emergency PAG, it therefore seemed appropriate to employ a more conservative margin of safety of two orders of magnitude, i.e., 100, relative to the emergency PAGs. This yielded a new intervention level for total cesium of 277 Bq/kg. However, the Agency obtained some preliminary data from a 1986 study that indicated a lower rate of meat consumption in the United States [6]. Consequently, a lower consumption rate resulted in a higher intervention level. In October 1986 FSIS adopted a 370 Bq/kg response level for total cesium to harmonize U.S. intervention levels for all food items. The highest total cesium levels had occurred by April 1987, for each of the 14 European countries [7]. However, on June 3, 1987 a sample of beef extract from Brazil was taken by an FSIS inspector who noticed, on routine inspection, that a large container of beef extract caused an unusually high reading on his scintillation survey instrument. An adequate sample for analysis was sent to the laboratory. The sample contained 481 Bq/kg and 168 Bq/kg of cesium 137 and 134, respectively. The total cesium of 649 Bq/kg, exceeded the FSIS response level of 370 Bq/kg. The cesium 137/134 ratio of 2.86, indicated a strong probability that the beef used in the product was from Chernobyl contaminated animals [7]. The Brazilian plant that produced the beef extract, 50 ------- stated that the meat used to produce the extract may have been imported from three European countries: Poland, Ireland, or Denmark. Based on the result of this sample, FSIS started a sampling program to determine the cesium levels in: 1) all non-distributed Brazilian beef extract products in the U.S., 2) all Brazilian beef extract entering the U.S., and 3) all products exported to the U.S. by the Brazilian plant Two out of the 60 beef extract samples exceeded the FSIS 370 Bq/kg intervention level. Subsequently, the contaminated product was prevented from entering U.S. commerce. A total of 122 samples of Brazilian beef products were taken during a four month period. In August 1987, FSIS stopped routine sampling of Brazilian product Thereafter, samples were collected only when the inspector obtained a significant response on the scintillation survey instrument Since all of these samples contained relatively low levels of cesium 134 and 137, a definite response of the instrument was in all probability due to the presence potassium 40, which is concentrated in beef extract. By October 1988, most of the samples contained cesium levels that were indistinguishable from background. Therefore, FSIS discontinued taking samples of product from European countries exporting meat and poultry products to the U.S. The Agency determined that any public health benefit of continuing the program was offset by cost consideration and resources that could be reprogrammed to other high priority areas. In total, FSIS analyzed 6195 samples of imported meat products from 14 European countries. 3701 samples of the 6195 were above background [Table I]. The highest values found were not necessarily from those countries with the largest number of samples above background. In summary, the following actions were taken by FSIS after the Chernobyl accident: Set a realistic intervention level using United States interim protective action guidelines (PAGs). Calculated the intervention levels by using both the maximum intake of radionuclide activity allowed and food consumption data. Monitored, sampled, and tested imported meat and poultry products for five radionuclides. Periodically assessed and revised the intervention levels based on good public health practices Continued to evaluate and assess the ongoing regulatory activities. Subsequent to these actions, "Derived Intervention Levels for Radionuclides in Food" was published by the World Health Organization [4]. Also a joint FAO/WHO recommendation to the Codex Alimentarius Commission to control foods in international trade that have been accidentally contaminated with radionuclides may soon help harmonization of intervention levels. The goal is to provide a system that can be uniformly and simply applied by government authorities and yet one that achieves a level of public health protection to the individual that is more than adequate in the event of a nuclear accident". [8] Codex represents a worldwide search for compromise and consensus based on science. Food Safety Officials have been instrumental in setting many of these guidelines; they supervise radiological monitoring of much of the food in international trade and food consumed in each nation; and they will continue to be more important in orchestrating new activities for the benefit of all nations. 51 ------- TABLE I: EUROPEAN SAMPLES ANALYZED FOR CESIUM 134 AND 137 COUNTRY NUMBER OF RESULTS ABOVE HIGHEST TOTAL NAME SAMPLES BACKGROUND CESIUM Bq/kg* BELGIUM 224 177 51 (9/86) CZECHOSLOVAKIA 63 59 42(1/87) DENMARK 1820 348 26 (3/*87) FINLAND 274 241 71 (1/87) FRANCE 239 15 <1 (1/87) GERMANY 57 20 7(3/87) HUNGARY 307 269 3 (4/87) NETHERLANDS 99 20 5 (11/86) POLAND 849 749 115 (8/86) ROMANIA 1425 1376 1043 (10/86) SWEDEN 571 229 83 (10/86) SWITZERLAND 68 36 165 (12/86) YUGOSLAVIA 188 157 86(3/87) TOTAL 6195 3701 Note: Numbers may change slightly pending final audit of data. * Total cesium is the sum of cesium -134 and cesium -137. ACKNOWLEDGEMENTS We thank Edith E. Kennard, Office of the Administrator and Kathryn L. Kimble-Day, Office of the Deputy Administrator for Science for their technical assistance in the preparation and editing of this paper. REFERENCES [1] HOHENEMSER, G, DEICHER, M., ERNST, A., HOFSASS, H., LINDNER, G., RECKNAGEL, E., Environment, Vol. 28 (1986) (5) :6 [2] EDWARDS, M., Chernobyl-one year after; National Geographic Magazine, Vol. 171 (1987) (5):633 [3] Nuclear Power -Accidental releases-practical guidance for public health action, WORLD HEALTH ORGANIZATION Regional Publications, European series No. 21:12,33 (1987). [4] Derived .Intervention Levels for Radionuclides in Food, WORLD HEALTH ORGANIZATION (1988) p. 13. 52 ------- [5] FDA, Accidental Radioactive Contamination of Human Food and Animal Feeds; Recommendations for State and Local Agencies. Fed. Reg. 47:47073. (1982) [6] BREIDENSTEIN, B., WILLIAMS, J., Contribution of Red Meat to the U.S. Diet, National Livestock and Meat Board. Chicago, IL.(1987). [7] ENGEL, R, RANDECKER, V., FRANKS, W., Lessons Learned From Chernobyl: Public Health Aspects; Journal of the Association of Food and Drug Officials, Vol 52 (1988) (1):15. [8] FAO, CODEX COMMITTEE ON FOOD ADDITIVES AND CONTAMINANTS (21st Session, The Hague, Netherlands) , Proposed FAO/WHO levels for Radionuclide contamination of Food in International Trade (1989). 53 ------- International Guidance Activities Allan C.B. Richardson Office of Radiation Programs US Environmental Protection Agency Washington, DC My charge today is to review international guidance activities on principles for setting Protective Action Guides (PAGs). It's really quite a simple task. There is only one set of guidance in existence now; that guidance is currently under revision; and we don't have the results yet. The principal group involved in generating this guidance is the International Commission on Radiation Protection (ICRP). Contributing groups include the International Atomic Energy Agency (IAEA) and the Nuclear Energy Agency (NEA) - which represents the European Community, primarily, and is part of the Organization for Economic Cooperation and Development (OECD). In the case of PAGs for food, there are some complicating factors; other agencies enter the picture - the World Health Organization (WHO), the Food and Agriculture Organization (FAO), and the Codex Alimentarius have been mentioned several times today. Skip Engel discussed that subset of considerations in an earlier paper. Here, instead of those more complex issues, we will focus on the basic principles upon which all PAGs are based. We need a common set of basic principles because we need to get to the bottom line (PAGs) in an unequivocal way that everybody understands. Let me give you an example of how equivocal some international organizations have been, on this question of PAGs, in the recent past. An unnamed international health agency, just a very few years ago, right after Chernobyl, set out to produce PAGs. They stated their intentions as two objectives. The first was: "... to set [Protective Action Guides], below which the introduction of control measures cannot be justified on the grounds of protecting health." But, they went on to recognize, control measures could still be introduced for other reasons, as health is not the sole criterion for decisionmaking. This first part of their objectives can be paraphrased as, "We will set a level below which you don't need to do anything, but you might do something anyway." The second objective was, "The [PAGs) will represent levels above which control measures should be considered, but not necessarily introduced." I would paraphrase this as saying: "We will set a level above which you should consider doing something, but you might do nothing anyway." I don't know how anybody could derive decisive action based on that set of objectives. International principles for setting PAGs are contained in two key documents that contain identical statements. One is Publication Number 40 of the ICRP, which was issued in 1985. The title is "Protection of the Public in the Event of Major Radiation Accidents, Principles for 55 ------- Planning." The other is the IAEA's Safety Series Publication Number 72, also issued in 1985, written by many of the same authors and titled, "Principles for Establishing Intervention Levels." The principles that were set forth in these documents were identical, were incomplete, and they are, unfortunately, the only principles that are now in effect, while proposed revisions go through one draft after another. There are several such draft revisions that are of significance. The most important is that of the ICRP. The basic guidance that applies to most planned exposure to radiation is ICRP Publication 26. That document has been under revision by the Commission for a number of years, and the new version will, for the first time, include recommendations for emergency response. They are now getting close to closure, and I think it should be a very much improved and useful document. But it isn't finished yet. Such guidance doesn't get developed in a vacuum, and there have been a couple of parallel efforts which have provided significant input to the ICRP, which is essentially a behind-closed-doors effort. These other efforts are more open. One of these is being carried out within the IAEA, which has convened annual meetings of national experts for a number of years in Vienna, to generate a replacement for Safety Series No. 72, mentioned earlier. There is a meeting scheduled this December to complete this effort; and, hopefully, we will reach closure at that meeting on at least the basic principles. The Nuclear Energy Agency (NEA) has also been at work. It has convened a group of experts from member nations that have been developing recommendations. There is an overlap between the ICRP, the IAEA, and the NEA groups, and they are all headed in the same direction. By this time next year, with luck we will have international agreement on the basic principles, and both the ICRP and the IAEA will have published their new reports. With that as a preamble, we can move to the principles themselves. These are shown in Figure 1, which lists the basic considerations for selecting PAGs. What should we expect the set of principles to say? It is fairly obvious, I think. First, avoid unreasonable risks of acute and long-term health effects. Next, avoid additional health risk when it is cost effective to do so; and finally, the risk from the protective action must be less than the radiation risk avoided. You certainly do not want to do anything which causes more harm than good. Figure 1 Basis for Selecting PAGs Avoid unreasonable risks of: Acute health effects Long-term health effects, and Avoid additional health risks when it is cost-effective to do so; but, The risk from the protective action must be less than the radiation risk avoided. 56 ------- In a little more sophisticated formulation, the NEA, in its review of the principles for deriving PAGs, has put together a chart showing their basic objectives. This is given in Figure 2, and shows how the ICRP 26 principles for normal situations translate into the accident situation. This transition from principles for normal situations is something, by the way, that has been resisted for a long time; the tendency has been to treat accidents as unique. Under ICRP 26 - that is, for normal radiation protection when you have a source that is under control and you are really deciding how much control you want to exercise -- there are three principles. They are called justification, optimization, and limitation (or constraints on individual risk). Justification is something which has usually already taken place before radiation protection people get involved - like the decision to have nuclear power or not. Optimization is, basically, making the choice of the best buy for the money in control. It's what we call ALARA The optimization process results in regulations like 40 CFR 190, the 25-millirem EPA standard that the nuclear industry operates under for normal releases. We all know the dose limits for limitation of individual risk. They are well established. The dose limits referred to here are the overall limits; for example, in the United States it is our 500 millirem Federal Radiation Protection Guide. Figure 2 NEA (April, 1989) Justification Optimization Constraints on total individual risk Normal case Source under control Justification of a practice Choice of the "best" option for control Dose limits for workers and for the public Accident Source out of control Justification of a protective measure Choice of the "right" intervention level Radiological risk and risk from protective measures kept below unacceptable levels Now, when you consider the accident situation, some interesting changes take place. You're no longer justifying the practice ~ the existence of the source ~ what you are justifying is the imposition of a protective measure. The source is already there. So the justification requirement becomes much more real. It's the determination that taking the protective action will do you some good. Optimization really remains the same - it's a question of where you get the greatest protection for the effort, including the cost. But there is a subtle difference. In the case of a source that is being controlled, you are usually looking at a discrete set of control options, e.g. what type of control of iodine releases do you install, or how much holdup of noble gases. Whereas, in the case of protective action you are really looking at the choice of the level 57 ------- of radiation exposure at which you introduce the protective action. This is a continuous range, not a set of discrete options. Finally, we must consider constraints on total individual risk. In the normal case, specified dose limits exist, e.g. the ICRP's current dose limits are 100 millirems for chronic exposure, and 500 millirems for non-recurring planned exposures. In the case of an accident, there are no numbers. In the international guidance under development, that will remain the case. What will emerge is a recognition that individual countries will have to make decisions about what level of protection they want to provide people, as an upper bound to risk under accident situations. But, it is not something on which numerical international guidance will be offered. Figure 3 shows the existing international principles, as they have been set down in ICRP-40. It is kind of a mess, really. The first principle is an example of limitation; it corresponds to the third principle on Figure 2. It is an upper limit on risk, but it only applies to nonstochastic effects. That is, there is no recognition of the need to provide an upper bound on health effects from stochastic effects in the existing international guidance. That is one of the things that needs to be fixed. Figure 3 ICRP40 Principles for planning intervention in the event of an accident: (a) Serious nonstochastic effects should be avoided by the introduction of countermeasures to limit individual dose to levels below the thresholds for these effects. (b) The risk from stochastic effects should be limited by introducing countermeasures which achieve a positive net benefit to the individuals exposed. This can be accomplished by comparing the reduction in individual dose, and therefore individual risk, that would follow the introduction of a counter-measure with the increase in individual risk resulting from the introduction that countermeasure. (c) The overall incidence of stochastic effects should be limited, as far as reasonably practicable, by reducing the collective dose equivalent This source-related assessment may be carried out by cost benefit analysis techniques and would be similar to a process of optimization in that the cost of a decrease in the health detriment in the affected population is balanced against the cost of further countermeasures. 58 ------- The second principle in ICRP-40 is the most difficult one to analyze. It actually is a requirement for justification of a protective action. What it really says is, "Don't do it if it isn't going to do more good than harm." The word "stochastic" is misleading here, because it implies that stochastic effects have been limited. They have not. This is a justification requirement, but not well expressed because it leaves out the costs implied by the protective action. And finally, the last principle is expressed correctly. It is a requirement for optimization, or ALARA. It is the only one that is expressed clearly and completely in the existing guidance. Figure 4 shows last year's draft of new principles prepared by an expert group for the IAEA. It is much clearer. There are three principles: justification, optimization, and limitation of the risk to individuals. The third principle adds to the old ICRP-40 statement the phrase " the level of total radiation exposure of individuals should be maintained below that which is regarded as unacceptable for stochastic effects . .." This level is not defined, and it's left to each country to decide what it's going to do. Figure 4 IAEA DRAFT REVISION OF PUBLICATION 72 (11/88) PRINCIPLES FOR ESTABLISHING INTERVENTION LEVELS Intervention should be justified (i.e. the particular action should do more good than harm for the group of people it will affect). The protection of the population should be optimized (i.e. the particular action should be implemented at the level which will produce the most good). The risks to individuals should be constrained below unacceptable levels (i.e. the level of total radiation exposure to individuals should be maintained below that which is regarded as unacceptable for stochastic effects, and below that which serious non-stochastic health effects could occur). Figure 5 shows what EPA has done in its revised draft revision of the PAG manual; it is essentially identical to the principles in Figure 4. We have tried to choose words that would be clearer. The first two principles here deal with the limitation of risk to individuals; they deal separately with nonstochastic and stochastic effects. They should be considered together as limitation of individual risk. The third principle is a requirement for ALARA, and the fourth one is a requirement that the protective action be justified, i.e., that it do more good than harm. 59 ------- 1. Acute effects on health (those that would be observable within a short period of time and which have a dose threshold below which such effects are not likely to occur) should be avoided. 2. The risk of delayed effects on health (primarily cancer and genetic effects for which linear nonthreshold relationships to dose are assumed) should not exceed upper bounds that are judged to be adequately protective of public health under emergency conditions, and are reasonably achievable. 3. PAGs should not be higher than justified on the basis of optimization of cost and the collective risk of effects on health. That is, any reduction of risk to public health avoidable at acceptable cost should be carried out. 4. Regardless of the above principles, the risk to health from a protective action should not itself exceed the risk to health from the dose that would be avoided. This summarizes the current state of advice on how to set PAGs. I would like to make two additional; points. One minor and one major. The minor one is that none of these sets of principles requires that the PAGs be expressed in terms of rems, or sieverts. They may be expressed in terms of any kind of indicator of exposure that is useful for deciding when to introduce a protective action. The second, and major point, is that I think we really need a fourth principle to be added to the three we have been discussing. That is to keep PAGs as simple as possible. This is essential so that political decision makers can go about the vital business of providing protection of the public without having to make complicated radiological health judgements that it is unreasonable to assume they are trained to carry out. 60 ------- Economic Criteria for Implementing PAGs for Food Byron Bunger Office of Radiation Programs U.S. Environmental Protection Agency In the case of an airborne release from a nuclear power reactor, agricultural land in the fallout zone may be contaminated with radioactivity. If the foods produced from this land are sufficiently contaminated that they pose a risk to consumers, public authorities can intervene on the basis of Protective Action Guides (PAGs) to prevent their entry into commerce. The limiting factor for selecting the PAG is the protection of public health. Once an acceptable level of risk has been determined, economic considerations can be introduced to determine whether the benefits of a lower PAG justify the additional costs. This is an investigation into the costs and benefits of the interdiction of specific foods representative of the broad spectrum of those produced in the U.S. The Costs of Intervention The types of food and the amounts of production interdicted determine the social costs of intervention. The amounts of production evaluated here range from minimums of a few units of production to maximums equaling the production of the largest producing States for each food. The Table shows the eleven foods evaluated, the State with the largest production of each, and the proportion of national production produced by that State (JF-89) . The social cost of interdiction is measured as deadweight loss. This is the loss to the consumers of the food that is not recaptured by its producers. The loss to consumers is reduced food availability and increased price for that portion of the food still available. The loss to consumers due to increased price for the food still available is returned to its producers with no net loss to society. Deadweight loss is the additional loss experienced by consumers which is not returned to producers. 61 ------- TABLE: CROPS AND SIZES OF INTERDICTION CROP 100% INTERDICTION STATE PERCENT BEEF EGGS CHICKEN TOMATOES MILK SWEET CORN LETTUCE SOYBEANS ORANGES SNAP BEANS WHEAT TX CA AR FL WI FL CA IL FL WI KS 13.3 12.0 16.4 48.9 17.6 30.5 71.7 163 30.5 35.5 17.6 The crosshatched area ABCD in Figure 1 demonstrates the deadweight loss for a representative situation. It is assumed that only one year's production is lost because of the intervention Caused by the reactor accident and, therefore, that farmers whose production is not affected by the accident are not able to respond to the accident by increasing their output. Therefore, the supply functions for the before and after accident situations are vertical and labeled. SI and S2 respectively. The loss in production is represented by the horizontal distance between SI and S2 (i.e. AB). Figure 1 DEADWEIGHT LOSS SI QUANTITY (MILLIONS OF POUNDS) 62 ------- The height of the line AD represents the price that would have been paid for the food had there been no intervention, but, more importantly for this analysis, it represents the loss to society due to the first few units of food production withdrawn because of the intervention. This loss to society is measured as marginal cost or the cost on a per unit basis. Similarly, BC represents the price paid for the food after the intervention and also represents the marginal cost to society for the last few units of production withdrawn. Some social costs of intervention, such as the destruction of foods and the value of health effects associated with the interdiction itself, are ignored here. They would be small in comparison to the other costs of interdiction and would have no appreciable impact on this analysis. The marginal costs of intervention, based on data for 1983 through 1985, are shown in Figure 2 (JF-89). The costs for three cases are shown: a small intervention (representative of AD in Figure 1), a large intervention equaling the production of largest producing state (representative of BC in Figure 1) and an intermediate intervention representing 10% of the production of the largest producing state. These are labeled as: minimum interdiction, 100% interdiction, and 10% interdiction respectively. Figure 2 COSTS & BENEFITS OF INTERDICTION ffl 0.0 1008 INTERDICTION 10* INTERDICTION MIN INTERDICTION 63 ------- The Benefits of Intervention In the following discussion of exposures experienced by consumers of the radioactively contaminated agricultural production, dose values are understood to represent the 50 year committed effective dose equivalent to the consumers. Since consumption takes place after all processing is completed and the foods have been marketed and delivered to the consumers, some radioactive decay will have taken place. This decay is assumed to be taken into account. The World Health Organization estimate of the average yearly intake of food is 600kg, which is equivalent to 1320 pounds (WH-88). If the PAG is expressed as a uniform dose from each unit weight of food intake, regardless of the type of food, a one rem per year dose (for example) is equivalent to a 1/1320 (=0.00076) rem dose from each pound of food consumed. EPA has published a guideline establishing the value of a statistical life. The value is expressed as a range, from a low of $400,000 to a high of $7,000,000 per life, expressed in 1982 dollars (EP-82). This is equivalent to a range from $490,000 to $8,580,000 per statistical life expressed in 1988 dollars, when adjusted by the consumer price index (CE-89). This range for the value of life is intended to be used only as a guide. The preferred method for using this guide is in terms of an implied value of life. In evaluating the implied value of life the net cost of a regulatory alternative is divided by the number of statistical lives saved and the result compared to this range. An alternative with an implied value of life falling within this range is judged to be reasonable. An alternative with an implied value of life exceeding the upper end of this range may be unreasonably stringent (and costly) and, perhaps, should be removed from consideration. An alternative with an implied value of life falling below the lower end of this range may not be stringent enough and, perhaps, also should be removed from consideration. Since this investigation addresses situations believed to be representative of those that may occur in the future rather than actual events, specific alternative interdictions are not evaluated. Therefore, the actual costs of interdictions are not compared to the value of life. Instead, representative interdictions are used to determine the exposure levels needed to justify their costs in terms of avoided risk. This is done in a cost-benefit framework. To do this, "rem equivalent costs" are determined. They are derived from the value of life and are expressed in units of dollars per pound-rem. The following calculations are to determine the range of "rem equivalent cost". It is assumed that the dose to risk conversion factor is 0.0004 deaths per rem in all cases (EP-89). Based on the lower end of the range of values of a statistical life, the value of a rem is (0.0004 deaths/rem) ($490,000/death) = $196/rem. Assuming the average annual intake of food is 1320 pounds, (1/1320) (196) = $0.148/pound-rem is the "rem equivalent cost". This means that, for a value of statistical life assumed to equal $490,000 and a risk of death per rem of 0.0004, the value of one rem is $196. This value, when translated to an annual diet, is equivalent to $0.148 per pound of food ingested. 64 ------- A similar calculation for the upper end of the range of values of a statistical life gives a "rem equivalent cost" of (1/1320) (0.0004) (8,580,000) = $160/pound-rem. These calculations establish the range for the "rem equivalent cost". The two extremes of this range are the bases for the two axes on the right side the Figure 2. These axes are scaled in dollars per pound, but are delineated in rems. They represent the marginal cost of consuming contaminated foods and are directly comparable to the marginal costs of interdiction shown on the left axis in the figure. Costs and Benefits Compared The two costs, the cost to potential consumers of the foods in terms of risk from exposure to radiation and the cost of interdiction, are tradeoffs, either one or the other is incurred for any unit of contaminated food. The objective of the cost benefit analysis is to identify the level of contamination (the PAG) that minimizes total cost to society. This is the level where the marginal cost and marginal benefit of interdiction are equal. (In this case the benefit is the risk avoided by not consuming the contaminated food.) Food contaminated above the PAG is interdicted because the marginal cost of withdrawal from the market is less than the monetary value placed on the incremental risk from its consumption, and food contaminated below the PAG is allowed to enter commerce because the marginal cost of withdrawal from the market exceeds the monetary value placed on the incremental risk from its consumption. The methodology used here makes it possible to identify the dose level where marginal costs equal marginal benefits although the total benefits of interdiction are not known, because the actual level of contamination is not knowable in the absence of an actual release. Note that consumers' payments for the foods if they were to enter commerce would not be social costs because they exactly balance the receipts of sellers, the net cost to society would be zero. In the discussion that follows it will be shown that value of life criteria can be helpful in establishing the PAG for interdicting foods. Figure 2 is used to determine the range of dose levels implied by the costs of intervention. For example, consider beef. Interdicting even a small portion of the beef producing industry would incur a marginal cost of $0.73 per pound of beef removed from the market. This is the minimum cost of intervention. The exposure levels equivalent to this cost range from 0.28 to 4.9 rem, depending on the value of a statistical life. For example: 0.73/(( 1/1320) (0.0004) (8,580,000)) = 0.28. Based on the upper end of this range (with a value of life equal $490,000), interdiction of beef is required if the exposure level exceeds 4.9 rems because to not interdict is to imply a value of life lower than $490,000. Based on the lower end of this range, interdiction is not to be carried out at levels below 0.28 rems because to do so implies a value of life greater than $8,580,000. In summary, when applying the value of life criteria to the interdiction of beef, where interdiction costs $0.73 per pound: interdiction should not take place where contamination levels are below 0.28 rem and should take place where contamination levels are above 4.9 rem. 65 ------- Interdiction may, or may not, take place when the contamination level is between 0.28 and 4.9 rems, depending on factors other than cost that may affect the decision. The proceeding discussion addresses the question whether any interdiction should be undertaken. In cases where it is undertaken, the size Of the interdiction must be determined. The 10% and 100% interdiction costs provide some insight into the relationship between the size of the interdiction and its cost. The upper end of the range of cost, 100% of the largest state's production, is chosen as a reasonable upper limit to the production interdicted because it is unlikely that an airborne release from a nuclear reactor would contaminate a larger area. The marginal cost of interdicting as much beef as produced in Texas is $1.04 per pound. The rem equivalents range from 0.40 to 7.0 rem. This means that an expenditure of $1.04 per pound to interdict beef can be justified, on value of life criteria, for exposure levels as low as 0.40 rem. A decision to interdict production equal that of Texas, if the marginal exposure level were below 0.4 rem, would imply a value of life greater than $8,580,000. On the other hand, a decision to not interdict production equal that of the State of Texas, if the marginal exposure level were above 7.0 rems, would imply a value of life less than $490,000. Establishing PAGs Reasoning similar to that employed above can be used in evaluating possible PAGs. The difference in reasoning is that the rem level is selected; then the range of costs that would justify that rem level, based on the value of life, is determined. Continuing with the example of beef, consider a 0.5 rem PAG. Any costs falling within the range $0.074 to $1.30 per pound can justifiably be spent interdicting beef contaminated at 0.5 rem. For example: (1/1320) (.0004) (490,000) (0.5) = 0.074. The interpretation is similar to that developed above for rem equivalent cost: to be unwilling to spend as much as $0.074 per pound to interdict foods contaminated at 0.5 rem is to undervalue life and to spend more than $1.30 per pound is to overvalue life. Lines representing these two costs are shown on Figure 2. Since the costs of intervention start at $0.73 per pound for the first few pounds of beef removed from commerce, beef could be interdicted if contaminated at or above 0.5 rem. The upper end of this range exceeds the cost of interdicting production equal that of Texas. Therefore, economic considerations do not impose limitations on a 0.5 rem PAG for beef. The objective in establishing the ingestion PAG for food is to set a single value which is applicable to all categories of food, rather than for just one category such as beef. The reasoning in evaluating a PAG for all food is the same as that used for beef. Again, consider a 0.5 rem PAG. As determined above, costs ranging from $0.074 to $1.30 per pound can justifiably be expended interdicting foods contaminated at this level. Inspection of Figure 2 shows that $1.30 per pound exceeds the costs of interdicting the maximum state's production for all foods investigated. Therefore, production exceeding that of the maximum producing state for each food can justifiably be interdicted if contaminated at 0.5 rem or above. The full range of costs of intervening most of the foods shown fall within this range. The reasoning for these foods is the same as that for beef. 66 ------- The marginal costs of interdicting small portions of wheat production falls below $0.074 and the marginal cost of interdicting production as large as that for Kansas is only slightly above $0.074. This is interpreted to mean that very large quantities of wheat can justifiably be interdicted if contaminated at 0.5 rem or above. This should not cause a problem because it is unlikely that the areas of contamination would be this large. It also means that the PAG for wheat could be established at a level below 0.5 rem. The highest possible PAG with a range of justifiable costs encompassing the cost of interdicting a small portion of wheat production is 0.378 rem. Justifiable costs for this exposure level range from $0.056 to $0.984. Note that this range does not extend high enough to cover the cost of interdicting as much beef as produced in Texas. Clearly there is no PAG with a range of justifiable costs encompassing the full range of expenditures required to perform all the interdictions shown in Figure 2. Therefore no single PAG has all the properties judged to be desirable under the value of Ufe criteria. A PAG equal to or below 0.5 rem is attractive from a public health perspective. Such a PAG could be selected for reasons unrelated to economics, or the consideration of the value of life. However, this discussion has shown that a PAG equal 0.5 rem has many desirable properties from an economics perspective. The costs of interdiction can be expected to rise dramatically as the PAG is lowered. Therefore, very low PAGs may be unreasonably costly and not justifiable based on the value of Ufe. This is an investigation of the costs of interdicting eleven foods believed to represent the broad range of those produced in the United States. The only changes that could result from investigating a broader range of foods would be to increase the range of costs of interdiction. Unless some foods not investigated have costs of interdiction much higher or lower than the costs investigated here, no change in these conclusions is expected. REFERENCES CE-89 COUNCIL OF ECONOMIC ADVISORS. Economic Report of the President, January 1989, Table B-58. EP-82 U.S. ENVIRONMENTAL PROTECTION AGENCY. Guidelines for Performing Regulatory Impact Analysis, EPA-230-01-84-003, December 1983. EP-89 U.S. ENVIRONMENTAL PROTECTION AGENCY. Draft Environmental Impact Statement for Proposed NESHAPS for Radionuclides, Volume 1, EPA-520/1-89-005, February 1989, Table 6-27. JF-89 JACK FAUCETT ASSOCIATES, Cost of Implementing Ingestion PAGs, Draft Final Report, August 1989. WH-88 WORLD HEALTH ORGANIZATION, Derived Intervention Levels for Food, 1988. 67 ------- SUBMITTED PAPERS ------- Issues Regarding the U.S. F.D.A. Protective Action Guidelines and Derived Response Levels for Human Food and Animal Feed Bruce Denney Environmental Monitoring and Emergency Planning Unit Radiation Control Section Minnesota Department of Health A review of the Food and Drug Administration's (FDA) rationale and methods for determining protective action guidelines (PAGs) and derived response levels (DRLs) (FDAa82, FDAb82) for human food and animal feed reveals the presence of ambiguous and contradictory information that should be clarified in order to improve the usefulness of the guidance. The differences in the criteria used to determine the Preventative and Emergency PAGs and DRLs, for example, are striking. The Preventative PAGs (and DRLs) are based on accepted health physics principles, e.g. risk factors, avoidance of fetal health effects, agricultural models, etc. The Emergency PAGs (and DRLs), however, are based solely on a traditional safety factor of ten. This difference in rationale becomes more conspicuous when the protective actions for these PAGs are compared: preventative protective actions involve low impact actions, e.g. removal of cattle from pasture, storage to allow for radioactive decay, etc., while emergency protective actions involve high impact actions e.g. isolating and condemning food products. These differences result in a contradiction: high impact actions, which may cause considerable problems and loss of income for farmers and food processors, are based on non-technical premises ("tradition"), while the low impact actions, which may only result in minor inconveniences to farmers and food processors, are based on solid scientific principles. Justifying or explaining these differences to farmers or to the media may be very difficult. Clearly there exists a need to review the basis and rationale upon which the Emergency PAGs and DRLs were derived in order to provide a more scientific explanation for their choice and use. In the FDA guidance (FDAa82), references are also made to ALARA and to the use of low-impact actions at doses lower than the PAGs. Although the FDA accepts and endorses the concept of keeping doses as low as reasonably achievable, the FDA does not support its use "under emergency conditions". In another part of the guidance, however, the FDA describes the concentrations at which the cost of implementing a protective action equals the risk avoided by (i.e., benefit of) the action. These concentrations are fractions of the DRLs, which suggests, as 71 ------- the guidance itself states, that it may be "appropriate to implement low-impact protective actions at projected radiation doses less than those specified in the guides". The resulting implication is that ALARA principles may indeed play an important role in ingestion pathway planning. The FDA should, therefore, re-evaluate its position on ALARA and should estimate the concentrations of radionuclides in human food and animal feed below which protective actions are unnecessary based on ALARA principles and cost/benefit evaluations. Finally, to determine if the PAGs for milk are being exceeded when mixtures of radionuclides are present, DRLs must be derived for radionuclides other than those currently in the guidance (i.e., 1-131, Cs-134, Cs-137, Sr-89, Sr-90). Such data already exists for more than thirty other radionuclides for water, produce, and leafy foodstuffs in the Federal Emergency Management Agency document entitled "Guidance on Offsite Emergency Radiation Measurement Systems, Phase 3, Water and Non-Dairy Food Pathway" (FEMA88). In conclusion, the basis and principles upon which the protective action guides and derived response levels for the ingestion pathway were created need to be re-evaluated to ensure that the guidance is technically valid and practical to implement. In addition, efforts should be made to improve the applicability of the guidance by including DRLs for other radionuclides which may be present in milk. REFERENCES FDAa82 Food and Drug Administration, "Accidental Radioactive. Contamination of Human Food and Animal Feeds; Recommendations for State and Local Agencies", Federal Register. VoL 47, No. 205, Friday, October 22, 1982, p. 47043. FDAb82 Food and Drug Administration, "Background for Protective Action Recommendations: Accidental Radioactive Contamination of Food and Animal Feeds", August 1982, FDA 82-8196. FEMA88 Federal Emergency Management Agency, "Guidance on Offsite Emergency Radiation Measurement Systems, Phase 3 Water and Non-Dairy Food Pathway" (Draft), October 1988, FEMA-REP-13. 72 ------- Concerns in Assessing Radiological Releases to a Major Estuary Leslie P. Foldesi Virginia Department of Health Bureau of Radiological Health In the State of Virginia, the James River flows into the Chesapeake Bay and from the mouth of the James River to the fall line the river is under the influence of tidal forces. There are several centers of commerce along the river including an international port of call at the mouth of the James. Associated with the centers of commerce are potential sources of radioactive materials for being released to the river. Two hundred miles inland, the Babcock & Wilcox nuclear fuels processing plants are situated along-side the James River, which has been known to flood its banks quickly in the mountainous regions of Virginia. Storage tanks have been swept downstream from this facility in a previous flood. Fortunately, the tanks were not destroyed. Another source of a possible release is the Surry Nuclear Power Station located on the James River about fifty miles from the Chesapeake Bay. In the cities of Norfolk and Newport News, shipyards are fueling and defueling the Navy's nuclear powered fleet. In addition, many of the Navy's ships are carrying nuclear weapons. These activities may also result in an inadvertent release. In assessing the radiological release from any one of the previously mentioned activities, it is obvious that dilution of the material released into the river is a major factor in dose assessment, as well as the fact that the water is brackish and not suitable as a source of potable water. However, dilution in this case may not be the simple solution. We also have to remember that this estuary is under tidal effects, which means that the materials may not be going out to sea to be further diluted as quickly as we would like to think. It may be possible that the material will be carried up river as far as the fall line and deposited, or deposited along the river's banks. From Virginia's experience with the pesticide, Kepone, materials may be deposited along the estuary and enter the food chain thereby necessitating the limitation of taking shellfish and commercial, recreational fishing. A major problem in assessing the environmental impact is determining what isotopes and in what forms will be taken up in species of commercial interest or those species that would otherwise contribute to man's exposure. 73 ------- Even though water in the lower James River is brackish, there may be uses for the water that have not been considered before, such as use by desalinization plants. Currently, the City of Virginia Beach has difficulty maintaining an adequate supply of water and there has been some discussion of building desalinization plants. If such a plant were in operation, the health physicist would have to consider the consequences of the material being concentrated and the problems associated with disposal of resins or contamination of the equipment. Most ships distill water while at sea and probably the still would not be operating while in port; however, the brackish water is used for fire fighting and many prove to be a source of contamination on the piers, unless an advisory was issued. At the mouth of the James River is located a major beach resort and in the event of a major release its business would suffer if the radiological conditions were not assessed and communicated effectively to the public promptly. I would like to conclude this discussion by stating that citizens in states surrounding the Chesapeake Bay have become very sensitive to the environment of the Bay and that they no longer tolerate rivers being used as sewers. As health physicists we also need to be sensitive to these issues and be mindful that estuaries are more complicated than a direct sewer drain to the ocean for wastes even though the discharges may be accidental. 74 ------- The Ingestion Pathway Comments and Issues Lawrence J. McDonnell Radiation Protection Council State of Wisconsin The Ingestion Pathway and its recent emphasis on planning for nuclear power plant emergencies has created activity at all levels of government. Federal Emergency Management Agency (FEMA) guidelines have been developed and there has been an urgency placed on implementing these guides and planning standards at all levels of government. This global approach has led to confusion and in some cases rapid development of public brochures at the state level. These brochures are meant to educate the public in the need for protective action in the ingestion pathway. Some forethought on the planning process and the integration of the protective action guidelines seems in order. Some issues that should be addressed are listed below: Suggested consideration of issues to facilitate the planning process: * Review existing technical specifications of nuclear power plants requiring environmental monitoring. This should provide at least the baseline sampling of food products for site specific plants. * Review state monitoring/analysis of sampling programs and NRC contracts to states for radiological monitoring of nuclear power facilities. * Encourage each state to involve food producers at an early date in the planning development Such producer associations as the Dairy Associations, Marketing Boards, and Cooperatives are valuable resources in implementing plans because they represent the affected economic impacted parties. * Involve and educate the agricultural extension agencies in the planning process so they can inform the public through their usual points of contact. * Set up principle agency responsibilities in existing state specific framework. For example, the farm or food producers normally are familiar with their extension agents. Use this relationship to help the affected producers understand the protective actions that will be implemented in case of severe nuclear power plant accidents. * Recognize that the disaster services agencies are lead agencies for implementing evacuation procedures but may have no experience in relating to food production or farming practices 75 ------- in the area. Agriculture extension agents and their communication networks may be the primary notification and implementation method used in protecting the food pathways. Integrate planning activities so that conflicts and confusion can be avoided. For instance, the requirements for monitoring the population in the EPZ require that 20% of the evacuated population require monitoring for contamination at reception centers located about 15 miles from the plant. Existing Food and Drug Administration (FDA) guides for protection of dairy products to 50 miles would indicate contamination of microcurie amounts of iodine and cesium at a reception center located 15 miles from the plant. This dilemma has been ignored in the planning process and makes one question the approach of the issuance of stand alone guides by the federal agencies. Emergency workers should be considered the same as the general public. If samples are gathered by emergency workers at locations (50-100 miles) from the affected area, it does not seem sensible to imply by protective dress that the population in those areas may be contaminated. The protective measures for these workers should be comparable to the risk that is involved. Standard Procedures and Analysis: One of the most difficult problems in assessing the radiological impacts for real events such as Three Mile Island has been interpreting the data. Often, the data is either incorrect or the errors are unknown. This leads to difficulty in taking correct protective action and loss of confidence in the entire emergency response system. The total emergency response program must include the federal resources at the outset. It is unreasonable to assume that the state should duplicate the federal resources in meeting the federal guidelines. 76 ------- Implications of the Chernobyl Accident for Protective Action Guidance Charles W. Miller Andrea J. Pepper Division of Planning and Analysis Office of Nuclear Facility Safety Illinois Department of Nuclear Safety The accident that occurred at Unit 4 of the nuclear power station at Chernobyl in the Union of Soviet Socialist Republics on April 26, 1986, was the worst accident in the history of nuclear power. Thirty-one workers and emergency personnel died and more than 200 site personnel were hospitalized as a result of this event Approximately 135,000 persons within 30 km around the reactor were evacuated, and radioactive debris was spread throughout the Northern Hemisphere. There was much public concern generated around the world, and an increased risk of fatal cancer in the world's population is possible as a result of exposure to Chernobyl fallout (USNRC, 1987a). Since the time the Chernobyl accident occurred, many authoritative studies have been published, e.g. USNRC, 1987a. In these studies, differences in design between commercial U.S. reactors and the RBMK pressure-tube reactor at Chernobyl have been emphasized, e.g. USNRC, 1987b. While significant differences in design do exist between these reactors, we believe there are still significant lessons to be learned from the Chernobyl accident for U.S. reactors. The purpose of this paper is to summarize some of the major lessons to be learned related to protective action guidance. The Illinois Department of Nuclear Safety (DDNS) has identified three areas related to protective action guidance for food and water where implications can be drawn from Chernobyl for the U.S.: (1) uniformity of Protective Action Guides (PAGs), (2) incompleteness of U.S. PAGs, and (3) international communications. Following the Chernobyl accident, a variety of protective actions were undertaken by various nations. Furthermore, these actions were initiated, modified, and terminated at different times in different places and, in some instances, were applied on a local or regional basis rather than a national basis (Goldman et al, 1987). One result of this differing application of PAGs was the generation of considerable confusion among decision-makers and the public, between and within countries, regarding appropriate levels of response. For example, one country may have considered a product acceptable for consumption while another country reported that the same level of contamination in the same product was too high for consumption. An accident in the U.S. could lead to similar discrepancies between States, and between the U.S. and other nations. Therefore, more emphasis must be given to both interstate and international 77 ------- cooperation in the development of PAGs. These guides should be developed using similar contamination action levels and applying consistent dose assessment methodologies. We recognize, however, that in the U.S. each State is responsible for protecting the health and safety of its citizens. Therefore, some differences between PAGs for different States may exist. Through workshops such as this one, though, the federal government can supply leadership to minimize differences in PAGs both within the U.S. and between the U.S. and other nations. PAGs have been developed in the U.S. for both the plume pathway (USEPA 1989) and for the food pathway (USDA 1982). However, the PAGs for the food pathway, which were developed by the Food and Drug Administration, specifically do not cover drinking water because drinking water standards fall within the Environmental Protection Agency's (EPA) area of responsibility. The EPA has not issued PAGs for drinking water, but it did issue response levels for radioactivity in finished drinking water during the Three Mile Island accident (USFDA 1983). During the aftermath of the Chernobyl accident, PAGs for drinking water sources were applied, e.g. in the Soviet Union (USSR, 1986). The EPA should move quickly to provide the States with practical guidance for drinking water. This workshop is designed to be a step in that direction, but it is only the first step. When this workshop is finished, EPA must use the information gained from this meeting to move forward with this guidance. As mentioned earlier, radioactive debris from the Chernobyl accident was spread throughout the Northern Hemisphere. Small, but measurable, quantities of fallout were even found in Illinois. Measurements of environmental concentrations and estimates of dose were made by many different organizations in many different places. One very noticeable difference in these values was the units used to report them. The U.S. continues to use traditional units of measurement for radiation quantities, e.g. 7 curies for amount of radioactivity and rems for dose, while most of the rest of the world appears to be adopting the new SI units of measurement, e.g. becquerels for amount of radioactivity and sieverts for dose. This difference has the potential for creating great confusion when radiological information is exchanged across international borders. We, like many U.S. health physicists, do not like some aspects of the SI system. It appears, however, that our objections have not been heard in the international community, and that SI units are here to stay. If that is the case, EPA should take the lead to help the U.S. move to SI units. All future PAG values, including those that result from this workshop and its subsequent proceedings, should be published in both traditional and SI units. All States and other federal agencies should also begin moving to SI units. One outcome of the Chernobyl accident has been a renewed commitment to international cooperation in the area of reactor safety and accident notification. Adoption of a universally-accepted set of radiation measuring units will enhance this process. There is one other area where the Chernobyl accident can be of assistance in utilizing PAGs. Mathematical models are an integral part of the PAG implementation process. For example, intervention levels for radionuclide concentrations in food and water are derived from PAG dose limits using environmental transport and dosimetry models. The process of testing model predictions with suitable data is known as model validation. The extensive amount of data developed from monitoring Chernobyl fallout provides an independent data set that can be used to test, or validate, the models used in dose assessment, including those used with PAGs (Richmond et al, 1988). International programs are being developed to test models using Chernobyl data, e.g., Hoffman and Doming, 1988. U.S. participation and support for these efforts, however, has been minimal. EPA and possibly other agencies of the federal government, should take the lead to increase U.S. 78 ------- participation in these model validation efforts. The information gained from this effort should be reflected in federal guidance and shared with the States in a timely fashion. Although significantly different in design from the Soviet RBMK, release rates similar to the Chernobyl accident have been postulated for U.S. reactors (USAEC, 1975). As a result, it is important that persons and organizations responsible for protecting the public in the event of a severe reactor accident learn as much as possible from the Chernobyl experience. The preceding paragraphs summarize some of the lessons related to water and food chain contamination that we believe can be learned from Chernobyl. Through participation in this workshop, as well as other activities, IDNS is actively seeking to apply all the knowledge we can gain from Chernobyl to protecting the health and safety of the citizens of Illinois. REFERENCES 1. GOLDMAN, M., CATLIN, R.J., ANSPAUGH, L., CUDDIHY, R.G., DAVIS, W.E., FABRIKANT, J.I., HULL, A.P., LANGE, R., ROBERTSON, D., SCHLENKER, R., AND WARMAN, E. 1987. "Health and Environmental Consequences of the Chernobyl Nuclear Power Plant Accident." DOE/ER-0332. 2. HOFFMAN, P.O., AND DEMING, E.J. 1988. The Use of Chernobyl Data for Model Validation" in "Proceedings of the ANS Topical Meeting on Emergency Response - Planning, Technologies, and Implementation," Charleston, South Carolina, September 26-28. CONF-880913. 3. RICHMOND, C.R., HOFFMAN, P.O., BLAYLOCK, E.G., ECKERMAN, K.F., LESSLIE, P.A., MILLER, C.W., NG, Y.C., AND TILL, I.E. 1988. "The Potential Use of Chernobyl Fallout Data to Test and Evaluate the Predictions of Environmental Radiological Assessment Models." ORNL-6466. 4. U.S. ENVIRONMENTAL PROTECTION AGENCY. 1989. "Manual of Protective Action Guides and Protective Actions for Nuclear Incidents." EPA/520/1-75-001 (Draft). 5. U.S. FOOD AND DRUG ADMINISTRATION. 1982. "Accidental Radioactive Contamination of Human Foods and Animal Feeds." Federal Register, Vol. 47, No. 205, pp. 47073-47083. 6. U.S. FOOD AND DRUG ADMINISTRATION. 1983. "Preparedness and Response in Radiation Accidents." FDA 83-8211. 7. U.S. NUCLEAR REGULATORY COMMISSION. 1987a. "Report on the Accident at the Chernobyl Nuclear Power Station." NUREG1250, Rev. 1. 8. U.S. NUCLEAR REGULATORY COMMISSION. 1987b. "Implications of the Accident at Chernobyl for Safety Regulation at Commercial Nuclear Power Plants in the United States." NUREG-1251 (Draft for Comment). 79 ------- 9. U.S.S.R. STATE COMMITTEE ON THE UTILIZATION OF ATOMIC ENERGY. 1986. "The Accident at the Chernobyl Nuclear Power Plant and Its Consequences." International Atomic Energy Agency. 10. U.S. ATOMIC ENERGY COMMISSION. 1975. "Reactor Safety Study: An Assessment of Risks in U.S. Commercial Nuclear Power Plants." WASH-1400. 80 ------- PAGS - Public Perception and Acceptance Robert M. Quillin Radiation Control Division Colorado Department of Health While Protective Action Guides or PAGs have been a part of the lexicon of the radiation protection field for several decades, the concept of accepting higher levels of risk under certain situations has not received adequate scrutiny by the general public, the media or elected officials. Consequently there is a question as to how implementation of PAGs would be perceived by the above groups in the event that such implementation became necessary. A personal case in point involves the response of an executive in the food industry. When the concept of selling a food product meeting the PAGs was explained his response was, "we won't sell a contaminated product, we would dump the unprocessed raw food. Our industry image is that of a natural unadulterated food". While this may be an isolated view, there is a need to determine what is the perception and consequently what would be the response if PAGs were implemented today. If the response was negative by anyone of the three groups listed previously, then there is an obvious need for a program to assure receptiveness by those concerned. However, this may face formidable obstacles. This is because the terms radiation and radioactive have gained generally negative word associations, e.g. "deadly" radiation and radioactive "desert". The former term was recently heard in a taped presentation at a Museum of Natural History on a completely unrelated subject. The latter term was part of a recent article heading in the Wall Street Journal. Incidentally the article was discussing television. Thus beyond the scientific issues of setting PAGs and the administrative and procedural issues of implementing PAGs there is the issue of society's understanding and acceptance of PAGs. Particularly, how can such understanding and acceptance be achieved in a situation which is associated with an actual or perceived radiation emergency? These are not questions that radiation or agricultural scientists can answer alone. These are questions requiring the additional input of social scientists. These are questions that also require the sponsorship of more than one particular discipline, agency or organization. This is to achieve a broader perspective and understanding of the issue and to stimulate creative ways of making PAGs work effectively if the need ever arises for their actual use. While PAGs may have a sound technical base, this is not sufficient alone to assure that they will work in today's sociopolitical environment. 81 ------- New Jersey's Experience with Implementing Protective Action Guides During the 1988 Salem Ingestion Pathway Exercise Duncan White New Jersey Department of Environmental Protection Introduction On November 30 and December 1, 1988, the New Jersey Department of Environmental Protection (DEP) and three other State agencies (Health, Agriculture and State Police) participated in the ingestion pathway portion of the 1988 Salem Nuclear Generating Station Emergency Exercise. The purpose of this phase of the exercise was to demonstrate the ingestion pathway components of the State's Radiological Emergency Response Plan (RERP) to the Federal Emergency Management Agency (FEMA). The intent of this paper is to provide a summary of difficulties and some lessons learned in implementing the DEP's ingestion pathway Protective Action Guides (PAGs) during the exercise as well as during the preparation of a total population dose estimate (TPDE). Summary of 1988 Ingestion Pathway Exercise The first day of the ingestion pathway exercise was concerned with evaluation of deposition measurements, selection and prioritization of sampling locations for foodstuffs, and the demonstration of sampling procedures. A majority of these activities were conducted at the DEP's Forward Command Post (FCP) located 11 miles east of the reactor site. Second day activities were conducted at the Department's decision-making location, the Technical Assessment Center (TAG) , located at DEP offices in West Trenton. The TAC's functions included: a. Screening analyzed samples based on either Environmental Protection Agency's (EPA) or Food and Drug Administration (FDA) preventive and emergency PAGs (response levels). b. Isolating and/or condemning foodstuffs on a municipal level using the attached decision-making criteria. c. Determining the fraction of PAGs using radionuclide concentrations. d. Making recommendations to the State Police on areas to be isolated and/or condemned for foodstuffs. e. Placing farm animals in the contaminated area on stored feed. 83 ------- In addition to the decision-making activities during the exercise, DEP submitted to FEMA a report that demonstrated the DEP's ability to estimate the total population dose for the scenario developed for the exercise. Problems Encountered Implementing PAGs The implementation of PAGs during the ingestion pathway exercise and their subsequent re-evaluation during the preparation of the TPDE raised a number of issues where additional guidance in the RERP would have made decision-making at the FCP and the TAG easier. A summary of these issues is presented below. 1. Sampling of Contaminated Foodstuffs a. What is a representative sample? b. How many samples are needed to adequately evaluate a property? A municipality? c. To make a protective action decision, should each type of crop be sampled? Each group of crops (i.e. leafy vegetables and produce)? A representative crop from each group? d. How should non-agricultural foodstuffs such as hunting and migratory birds be handled? Lessons Learned For ease of implementing PAGs, DEP used one sample from each crop group to either isolate or impound all foodstuffs for a municipality. The sample used in the decision-making process was usually taken in the area of highest deposition concentration and consequently represented a conservative sample. Although hunting (especially deer) can be controlled at weigh-in stations, the control of migratory birds is more complicated due to the large migratory range (entire Eastern Coast). 2. Application of Individual Radionuclide Response Levels a. What de-minimis level should be used? b. Should the thyroid continue to be treated as a critical organ or integrated into a whole body dose? c. Only during the TPDE evaluation was DEP able to better quantify radionuclide intake by age groups. Should the most sensitive portion of the population be used to evaluate ingestion or should all age groups be considered? Lessons Learned The DEP accepted EPA/FDA Position on these issues, but feels that future guidance must address these. 3. Implementation of PAGs a. What is the appropriate target population for contaminated foodstuffs? b. What and how much data is needed from the field sampling teams? 84 ------- c. Should doses from other phases of the exercise (plume and deposition) be included during decision-making for ingestion PAGs? Lessons Learned The target population was assumed to be the municipality where the crop was grown or harvested. There was no easy means to determine the distribution of these crops to market due to the proximity of large population centers (i.e. Philadelphia and New York). In addition, there are a large number of truck farms with multiple crops which influences the effective implementation of the PAGs. There was a tendency to use one short-lived radionuclide (i.e. 1-131) and one of two long-lived radionuclide (either Co-60 or Sr-90) in determining PAGs for foodstuffs. Due to the time constraints during the exercise, it was later discovered during the TPDE that some initial decisions were erroneous because other radionuclides were not included or were more restrictive. 85 ------- Decision Criteria For Recommended Ingestion Pathway Protective Actions Contaminating Event Potentially Contaminated Food, Milk, Water > 1-131 Emergency Response Level Field Monitoring OX for NorMl Use < 1-131 Preventive Response Level > 1-131 Preventive and <1-131 Emergency Response Levels Other Long-Li ved Radionuclides SUH<1 Isolate Food fron Market, Store for frantitative and Qualitative Analysis Divert for Use in Manufactured Products Concentration of Muclide ft Preventive Response Level A Concentration of Muclide B Preventive Response Level B Concentration of Muclide C Preventive Response Level C ------- WORKING GROUP SUMMARIES ------- SUMMARY REPORT OF WORKING GROUP ONE Chairman: Bruce Denney, Minnesota ISSUE: For what protective actions and situations are ingestion PAGs needed? 1. What are the problems and benefits of having different PAGs for emergency and non-emergency accident conditions? Likewise for near-field and far-field conditions with respect to time and distance from the accident location. After much discussion regarding what this question really asked, it was determined that the words "need for food" should have been added after the "non-emergency". So the question really referred whether or not there is a need to have different PAGs for accidents in which there is a normal uncontaminated supply of food and for accidents in which there is a shortage of these foodstuffs. The group concluded that PAGs (protective action guidelines) should address "normal" accidents, i.e. those in which there are foodstuffs available. Modifiers or multipliers of some sort should be applied to other specific situations. In terms of defining what the PAGs should be, many group members believed that a single numbered approach would be easier to use than the present two-tiered Preventative-Emergency approach and that such a system would be more in line with what is happening on the international level. In addition, mention was made of using a system of derived intervention levels, e.g. that are present in the CODEX document, instead of dose levels. With regard to far- and near-field situations, many opinions were expressed regarding what they really are. Is near-field for the ingestion pathway the 50 mile EPZ or the country from which the contamination originates from? Is far-field anything greater than 750 miles away or is it a neighboring country affected by the fallout? In any case, the group decided that the same PAGs or derived intervention levels should apply to either situation - near- or far-field. Lastly, in terms of the time factor, it was determined that one year was the appropriate amount of time that the PAGs should be applicable. After one year, long term guidance involving lower PAGs or models incorporating planned exposures should be incorporated. 2. Which types of conservatisms are appropriate and which are not appropriate for consideration in the development of PAGs? Which conservatisms may be best relegated to derived response levels or other guidance? The workshop group decided that the conservatisms used in the development of the PAGs and DILs (derived intervention levels) should be the same. Factors such as age dependent DCFs (dose conversion factors), diet, pertinent radionuclides and pathways were discussed. It was agreed that agreeing on the proper conservatisms was a very difficult task - but that 89 ------- somewhere along the line, it must be done. Many of the group members felt that the PAGs should be based on doses to standard man and that there are enough conservative assumptions built into standard man DCFs, that use of the DCFs would also protect more sensitive population segments, e.g. infants. Use of such a PAG would only involve calculating the dose for adults and eliminate the need to also calculate doses for infants. Other discussions also demonstrated that many people have differing ideas as to what PAGs really are. Are they doses? concentrations? guides? or guidelines? Are PAGs and PARs (protective action recommendations) separate entities or are they part and parcel of the same thing? Some members expressed a concern that the definition and use of this term should be clarified in the guidance and that some other term, e.g. intervention level, etc., might be a better term to use. Lastly, it was expressed that PAGs and DILs may be of little practical use, since State governors are often the ultimate decision makers in the States, and are free to change PARs based on political, economic or other considerations. Perhaps there is a need for adjacent States and countries to have memorandums of understanding to agree upon the PAGs and PARs that they will use in case of an accident. 3. What type of guidance is needed regarding cumulative dose? What are the problems and benefits of this type of guidance? After some discussion it was decided that the term cumulative dose referred to the sum of the plume dose, re-entry-relocation dose, and ingestion-dose - not the collective or population dose. It as the view of most of the group that there is no need to sum these doses and that each one should be treated independently of the others. This is further addressed in a later question. 4. Which protective actions for the ingestion pathway need specific PAGs? Discussions within the work group indicated that there are three groups of protective actions that may or may not need PAGs: 1) High impact protective actions, e.g. embargoing, in which concentrations or doses are greater than the interdiction levels or PAGs (e.g. DILs = CODEX criteria), need protection actions. 2) Long term protective actions, e.g. seedling, liming soil, etc., need protection actions. 3) Low-impact preemptive or precautionary protective actions, e.g. puting animals on stored feed, may not need PAGs because they're done for ALARA purposes. 90 ------- 5. What are the problems and benefits of having a specific PAG for each protective action? There are a wide variety of radiological situations that may justify the development of PA specific PAGs. The use of such multiple PAGs, however, may actually hinder PA decision making processes due to the increased complexities and time involved in manipulating and assessing the PAGs. To minimize these potential problems, it may be best to establish a smaller number of PA/PAG combinations that would be applicable to many different accident scenarios. 6. What problems should be addressed in developing separate PAGs for water and food? A major problem in developing PAGs is that guidance appropriate for specific accident scenarios, e.g. nuclear power plant accidents, may not be appropriate for other types of nuclear-related accidents. This process is further complicated by the existence of many jurisdictional divisions within the federal government, each of which has its own authorities and methods of doing business, etc. Although it may be "cleaner" to keep agency guidance separate, the development of uniform PAGs applicable to all radiological accident situations may be more effective. With respect to PAGs for water and food, for example, the working group decided that there is a need to develop a PAG for water for emergency conditions and that this PAG should be similar to the PAG for food under similar conditions. Another consideration brought up in the group is that if all water treatments can lower concentrations to levels less than the 4 millirem per year limit, why bother with an emergency water PAG? 7. What environmental conditions differentiate between emergency and non-emergency accident conditions for ingestion exposure pathways? This question was not discussed by the working group. 8. What problems should be addressed in the development of separate PAGs for home produced or collected food and drinking water as compared to food and drinking water in commerce? The working group decided that the PAGs for both situations should be the same, but that the protective actions for these groups may be different. For example, commercial apple growers may need to clean their apples in a manner different than the homeowner with a few apple trees should take. It was also decided that it may be necessary to identify special population groups that may require special PARs. The best means of identifying these groups is by using local agricultural agents. 91 ------- 9. What problems should be addressed regarding the relationship of ingestion PAGs to other categories of PAGs? The question refers to summing plume, recovery and ingestion doses together. The working group decided that this is not appropriate during the emergency phase or first year, but that there may be a benefit for establishing such a dose limit for long term exposure. This should be addressed in future recovery guidance. In addition, concern was expressed regarding the confusion or dilemmas that conflicting or incompatible federal guidance may create. An example of this is the FEMA requirement for decontaminating 20% of the 10 mile EPZ population at relocation centers which may be located only 15 to 20 miles from the affected plant. If these centers are in areas which are considered to be contaminated because of ingestion pathway concerns, the surrounding groundshine may inhibit decontamination efforts by masking the contamination on the evacuees themselves. In addition, there may be little merit in decontaminating evacuees when they may become recontaminated as they exit the decontamination facility. Clearly there is a need for federal agencies, States, etc., to confer and consult with each other so that consistent and coordinated guidance will be produced. To make this guidr^ce work, of course, concurrence must be reached by all of the agencies involved. 10. When should ingestion PAGs be replaced by limits for population exposure under normal conditions? What problems should be addressed regarding this topic? The working group obtained clarification on this question and determined that the question was not one of using the population doses as a basis for initiating PARs, but rather by deleting the word "population" from the sentence - was a question regarding how long PAGs should be applicable. This was determined to be one year, after which the limits of exposure should become more in line with the limits for normal operations. 11. What problems should be addressed with regard to special categories of foods and special population groups? The working group decided that special foods and population groups should be treated as exceptions to the general PAG guidance and that such cases may merit individual PAs. Questions were raised regarding the point at which these PAs should be applied - i.e. during processing; at end point of consumption; etc. This needs further evaluation. 92 ------- SUMMARY REPORT OF WORKING GROUP TWO Chairman: Charles W. Miller, Illinois ISSUE: What considerations should be evaluated in the process of selecting PAG values for ingestion pathways? This Working Group addressed the issue "What considerations should be evaluated in the process of selecting PAG values for ingestion pathways?". During its deliberations, the Working Group considered nine questions, eight developed by EPA staff prior to the meeting and one based on discussions during the first half-day of the Workshop. Each of these questions is listed below, followed by a summary of the Working Group's conclusions about that topic. 1. The basic principles for selecting all PAG values can be summarized as: Avoid unreasonable risk of radiation induced health effects, and avoid additional health risk when it is cost effective to do so; but the risk from the protective action itself must be less than the radiation risk avoided. What problems may be encountered in applying these principles to ingestion PAGs? Are additional principles needed? The first principle listed involves the idea of setting a PAG on the basis of health risk. This principle is the chief driving mechanism in the process. Health professionals often state that this principle should be the only principle for setting health related standards. Standards are actually based on "acceptable risk", however, rather than just pure health risL The second principle listed is difficult to implement and a source of great controversy. It may be implicitly involved in the "acceptable risk" decision, however, even when its explicit inclusion is vehemently avoided, i.e., there are limits to what society will pay to lower the risk. The third principle is more of an implementation problem than a PAG-setting problem. Basically, it says there are exceptions to every rule. Often, this principle is not quantifiable, and it is subjective rather than objective. For example, following the Chernobyl accident, Sweden raised the allowed limit for radioactivity in reindeer because their original PAG would have caused unacceptable societal costs to Laplanders. The Working Group also suggests that a fourth principle be added to the list: The PAG system developed should be as simple as possible. For example, one should not develop different PAG guidance for different phases of the accident. An overly complicated PAG system will only lead to confusion for both those officials 93 ------- who must apply the PAG and those members of the general public who must ultimately implement any protective action recommendation. 2. What problems are introduced or avoided by the use of fixed value PAGs as opposed to ranges of values? Where ranges of PAGs are used, confusion, indecision, and disagreement may result when deciding which PAG to use. There is, in many cases, a tendency to accept the lower, more conservative number as the predominant PAG. There may be justification for ranges of PAGs, such as socio-economic reasons; but if ranges are used, plans should stress when and how the ranges are to be used. Single PAG values are much easier to implement and, in most cases, will result in fewer problems than a range of PAGs. Even when single values are used, they may be adjusted according to circumstances which may warrant changes. In summary, we recommend that PAGs be based on dose and be single fixed values. 3. What problems should be addressed regarding harmonization of PAG values between States and between countries in the selection of PAG values? Are the problems different where commerce is the issue? Units? The only way of achieving protection without falling into the "zero risk" trap is to have credibility. Therefore, it is essential that everything reasonable be done to give any PAG credibility. Some of the things needed to achieve credibility are: Scientifically supportable. Accepted by the States. Accepted by all other relevant governmental jurisdictions. Preferably accepted by other countries. A single value (rather than a range). Costs must be considered, and the costs expended must be reasonable (neither too high nor too low). EPA can play an important role in helping to achieve credibility. It speaks with a single voice, is authoritative, and speaks for the whole nation. Nevertheless, in order to establish a credible PAG, the EPA must: Work with the States in establishing the PAG (or, perhaps, with CRCPD or a subcommittee of CRCPD). 94 ------- Demonstrate a good faith effort in dealing with the concerns of the States and with other public interest groups (although generally it will not be possible to completely satisfy each State or public interest group). Credibility and harmonization between States is the best way of impeding political interference by State governors. EPA is probably the best agency to work towards harmonization between countries. It must be recognized that harmonization between countries will be much more difficult to achieve than harmonization between States because of variation in level of economic development, cultural values, and perception of risk. There is no agency or body that speaks for the whole world in a way similar to the role played by EPA for the nation. PAG values should probably be expressed in international units. This is especially important in achieving harmony between countries. 4. What social/political problems should be addressed in the selection of PAG values for ingestion pathways? The social/political problems which are faced in the use of PAGs are related to the need to communicate with the public and decision makers in simple, direct language which will be accepted by those groups. This presents the difficulty of the use of terms which are understood by the public and decision makers (e.g., safe levels) versus terms which are used in radiological health (e.g., comparative risks). In addition to communication issues, there is a need for consistency with other similar guides or standards. The terminology used should be the same. In the international community the terminology used is Becquerel and Sievert. It is recommended that PAGs should be stated in the same terms for consistency and ease of comparison. Compatibility of standards is a key to acceptance, as is simplicity and consistency. 5. What problems need consideration in selecting PAGs for particular exposure pathways and population groups? The iodine-milk-infant pathway is considered a critical exposure pathway. Differences between the diets of the general population and infants may also need to be considered, as an infant's diet is predominantly milk. A standard U.S. diet should be established. This will allow all to know the basis for PAGs, and everyone will have the same guidance. The guidance needs to thoroughly explain the assumptions and data supporting derivation of PAGs. In going from dose to Derived Intervention Levels (DILs), the rationale/reasoning for this conversion must be carefully explained. 95 ------- The group suggests using a single dose PAG for all ages of the general population; do not establish an infant-only PAG. Also, during an emergency, the same number should be used for milk and water. EPA should emphasize that the PAG is a generic calculation for decision making only, not an indicator of actual dose to a person. It is the responsibility of States and local governments to apply PAGs to special population groups under their jurisdictions. 6. What problems require evaluation with respect to selection of PAG values to apply to different types of accidents (e.g., accidents involving primarily beta-gamma emitting nuclides versus those involving primarily alpha emitting nuclides)? In applying these PAGs to DILs, if the peak concentration value is used, more information needs to be developed on weathering, root uptake, and other factors that affect the projected human intake. If a constant concentration is used, this problem should not be there. 7. What problems should be evaluated regarding a change in the dose quantity from c' jmiited dose equivalent (CDE) to committed effective dose equivalent (CEDE) with special limitations to the thyroid in terms of committed dose equivalent? There will be public perception that government is pushing the limit up if we do not have a separate limit for the thyroid. International recommendations have separate limits for organs. To ignore them will require justification. Mixing CEDE with CDE is contrary to the proposed principle of simplification. The factor of 3 difference between the .03 weighting factor for thyroid and the international limitation of 10 times the CEDE value for organs may not be significant if other uncertainties are considered. 8. What problems are created or solved by considering the cost of specific protective actions? Cost is usually implicitly considered in most health or protective actions. The difficulty is the explicit consideration of cost because it has numerous (and almost inherent) uncertainties in the calculations. Those factors used (and assumed) can be calculated by many individuals or groups, resulting in continuing controversy. Cost should be analyzed as part of the evaluation on whether achieving the proposed level is reasonable. If cost is used explicitly in developing dose or derived levels for specific foods or food actions, this will likely result in different levels and destroy the simplicity of the guidance. It will then be difficult to explain why higher levels are allowed in certain cases. 96 ------- In conclusion, a basic cost analysis should show the acceptability of the levels selected or other factors (i.e., acceptable risk). That is, such selected values should be used unless the cost analysis shows that the cost of achieving such levels is unreasonable. 9. Should there be separate PAGs for food and water? The group suggests one number for water and milk. (This will help with public perception.) Water and milk should be generally considered as food. EPA should take into consideration how this one PAG number impacts both the adult and child. 97 ------- SUMMARY REPORT OF WORKING GROUP THREE Chairman: Michael Mobley, Tennessee ISSUE: What considerations are important for the development of guidance for protection from contaminated water? Herein is provided a narrative of the conclusions reached by Work Group 3, which was tasked with the problem: What considerations are important for the development of guidance for protection from contaminated water? The Group was chaired by Michael Mobley (TN) with Charles High (PA) as the scribe. The narrative is driven to some extent, by the example topics provided in the guidance to the Work Groups. 1. What problems should be evaluated regarding the allotment of a portion of the ingestion PAG to drinking water as opposed to having separate PAGs? The group response to the question went beyond the scope of the question and addressed a proposed fundamental philosophy for the entire ingestion PAG issue. Several axioms or boundary conditions apply to the philosophy. a. The PAG is an effective whole body equivalent dose commitment. b. The PAG for ingestion should be considered separately from those for plume exposure and for reentry and relocation. c. The PAG for ingestion should include anything that is put into the mouth and swallowed; i.e. food and water considerations are combined rather than assigned separate and distinct PAGs. d. The practical expression of the PAG should be in terms of concentration (pCi/1 or pCi/kg) of each specific radionuclide likely to be encountered. This concentration should be called the Interdiction Level. e. The Interdiction Level is applicable at any stage in the food/water processing for consumption; from raw to packaged. f. The term "interdiction" means that reaching or exceeding that concentration requires a conscious decision. It does not mean condemnation. g. Where a mix of isotopes is observed in a sample, the sum of the fractional Interdiction Levels shall not exceed unity. 99 ------- h. Compliance should be determined by radioassay. Protective Actions, however, are not necessarily contingent on radioassay. i. Consideration could be given to parceling the PAG into three compartments; for example, water, solid food, and milk based on model diets according to relative consumption rates (liters per day or kilograms per day), and using the most sensitive group for each vector. j. If only one vector is contaminated, say milk, the entire PAG may be used for that vector. 2. What exposure pathways from contaminated water other than drinking water are likely to be a problem? a. Given the system described above, problems should be minimized, since water is water. See also items 6, 7, and 8. 3. What problems may be caused by surface runoff? What types of guidance would be appropriate? a. Occurrence of runoff should require additional monitoring to assess consequential changes in water concentrations and isotopic mix. Then apply principles in topic 1, above. 4. What situations or special population groups may cause specific exposure problems that require guidance? a. The combined PAG is driven by the most sensitive group for each vector. Also since the Interdiction Level applies to any level in the process, most food fetishes will be indirectly addressed. No guidance is needed for the short term, say, the first year. 5. What monitoring problems need evaluation and resolution? a. Calibration sources shall be NBS traceable. b. The chain of custody for samples should be established. c. The Lower Limit of Detection (LLD) for each analytic method should be defined mathematically. d. The required value of the LLD should be established for each nuclide, and perhaps each vector if the PAG is to be allocated among water, food and milk. For example, should the LLD be 0.1 of the Interdiction Level, or should it be 0.05? e. A protocol for sampling priorities should be developed; i.e. what do you grab first. 100 ------- f. A protocol for analytic considerations should be developed, a sort of triage. This is due to the fact that the lab capacity for through put will be the constrictor in the process. 6. What problems, solvable by guidance, are related to contaminated water (non-drinking water) under accident conditions? a. Consideration of drinking water for livestock and water for irrigation are beyond the scope of this discussion. 7. What problems or benefits should be evaluated regarding water treatment facilities? a. Two problems are the disposal of flock and other water treatment wastes, and the disposal of sewage sludge. The resolution of the problem will require some method of determining the point at which these wastes will require special treatment, and by whom. b. Some thought should be given to the limiting concentration, if any, for the use of water for sanitary purposes and for fire protection. 8. What problems are related to the weathering of water systems? How do they relate to the type of system? a. Turnover rate must be considered along with the body of water in question with rivers of concern for shorter periods, and reservoirs for longer time frames. b. Guidance is needed for the selection of a removal coefficient or its derivation based on decay, weathering, and turnover. 9. What problems can legally be solved by dilution? a. It is customary to blend water to achieve desirable water quality. b. Deliberate dilution of food for the purpose of lowering a contaminant concentration is not an acceptable practice, according to FDA rules. 101 ------- SUMMARY REPORT OF WORKING GROUP FOUR Chairman: Duncan White, New Jersey ISSUE: What guidance is needed to support implementation of PAGs for ingestion exposure pathways? Summary This report summarizes the discussions of Working Group 4 at the "Workshop on Protective Action Guides for Accidentally Contaminated Water and Food". The Working Group discussed the guidance needed to support implementation of Protective Action Guides (PAGs) for the ingestion exposure pathway. The group expressed concerned that any derived response levels (DRLs) that were developed for contaminated foodstuffs should be as simple as possible and uniformly implementable. This concern resulted in the group recommending guidance which would serve as the basis for developing DRLs per radionuclide per given food group. The Working Group envisioned the PAGs implemented as a single set of DRLs based on the entire diet being contaminated for the maximum exposed group in the population. It was felt that PAGs based on DRLs derived in this manner would provide sufficient protection to the entire population. Since the DRLs were derived for the most critical group in the population, there should be no need for different DRLs for special population groups. The remainder of the paper summarizes the Working Group's discussions and/or consensus on the 11 topic areas identified for this issue. Discussion of Topic Areas 1. What problems or benefits are associated with the categorization of DCFs and DRLs for nuclides into two or three values for the purpose of simplification? How do these problems relate to special population groups? The Working Group felt that dose conversion factors (DCF) and particularly DRLs used for the implementation of ingestion PAGs should be as simple as possible. In the course of the group's discussion of this topic, a number of issues were identified and discussed. a. PAGs should apply to all nuclear accidents, although it was recognized that the greatest application of the PAGs would be nuclear power plant accidents due to the radionuclides involved and area impacted. b. The methodology for implementing PAGs should be provided to the States so that their implementation would be uniform and consistent. Specific examples would include sampling protocols, analytical procedures, DCFs and food intake factors. c. Under current guidance, direct measurements of the foodstuffs in question are needed in order for the authorities to interdict and remove the contaminated foodstuffs from the market. The group agreed that the authorities should be able to interdict foodstuffs 103 ------- without any measurements because it would provide more time to evaluate the impact of the accident Likewise, there should be no geographic limitation on interdiction. Decision- makers need the flexibility to look at the overall seriousness of the situation and balance potential losses. d. International guidance should be considered during the development of guidance for the U.S. e. PAGs should be expressed as whole body dose equivalent. f. The discussion of applying PAGs to special population groups lead to the consensus that the DRLs should be structured around the most critical group in the population. If this is done, there would be an added level of safety for the rest of the population and no other special group needs consideration. The group identified as the critical group for nuclear accidents impacting the ingestion pathway were farmers because they had the highest potential of any group in the general population for consuming home-grown foodstuffs. 2. What problems or benefits are associated with assuming that the entire diet is contaminated for purposes of conservatism and simplification? This issue is a continuation of the critical group approach discussed in the previous section. Since the local fanners would probably have the largest portion of their diet from food and water taken directly from contaminated areas, assuming that their entire diet is contaminated, would provide sufficient protection to the remainder of the population. Assuming that the critical population's entire diet is contaminated does raise a number of important issues. a. Assuming that the entire diet is contaminated makes the calculation of DRLs simpler. A single DRL per radionuclide per foodstuff could be determined. If multiple nuclides are involved for a single foodstuff, their sum should not be greater than unity. b. The risk of assuming that the entire diet is contaminated is a DRL that is too conservative because of the assumptions introduced. Examples of conservatisms introduced would include: assuming that the entire diet is contaminated, use of peak radionuclide concentrations instead of average concentrations and protection from stochastic effects based on the population versus an individual. The best way to limit the overly conservative nature of the DRLs would be the evaluation of several scenarios with the range of diets expected in the population. This would provide an assessment of what is likely to really happen instead of the worst case. This type of evaluation is analogous to Reactor Safety Study (WASH-1400). c. Not everyone has the same diet. The single DRL determined for a particular food stuff may not offer the level of protection intended because it may have been derived based on a particular mix of foods. In these cases, the DRL could be used as a screening level until a site-specific dose assessment is performed. 104 ------- 3. What implementation problems are associated with having different PAG values for emergency response and for food in commerce under accident conditions ? The Working Group recommended that only one set of PAGs be used for all foodstuffs. The system with two tiers of PAGs, one for emergency conditions and a second one for commerce or preventive situations could not be implemented. The lower or preventive PAGs would become the only guidance utilized. The food with radionuclide concentrations between the two tier levels would not be utilized because of its acquired label. With the one tier system, there is sufficient protection to the population because if the maximally exposed individual meets the DRL, then the rest of the population should meet the PAG. 4. What should be done to increase public comprehension and improve communication with the public regarding radiological emergency response planning and guidelines? In order to improve the public's comprehension of radiological emergency response planning and guidelines, the group identified two courses of action. The first would be the creation of a document that is prepared for non-technical people such as reporters and political officials. Secondly, intervenor groups and the public should be briefed on the basic concepts and how the DRLs were derived. 5. What problems can be solved by evaluating the effectiveness of specific protective actions? The best place to evaluate the effectiveness of the PAGs would be in the marketplace at the wholesale level. At this point, if there are still radionuclide concentrations in excess of the DRL, then interdiction would be more effective than at the retail level. The group felt that a de-minimis criterion is needed to stop testing foodstuffs on an emergency basis. It would serve as a benchmark for the transition from emergency to routine monitoring. In the laboratory, this would have practical implications since the level of analytical sensitivity is different for emergency samples compared to the routine samples. With regard to estimating the total population dose, the existence of a de-minimis level would limit the extent of the assessment. 6. What implementation problems have been experienced with regard to specific protective actions? What evaluations or guidance is needed regarding these problems? As discussed above, the use of two tier system is not practical and should not be recommended in federal guidance. For example, there is little chance food processors would accept milk with radionuclide concentrations between the preventive and emergency PAG to make cheese or ice cream. This highly unworkable scenario and ones like it should not be endorsed or suggested in the guidance. The use of a single tier system eliminates these types of problems. The development of PAG guidance should look at reasonable scenarios such as power plants and transportation accidents. The nuclear war/general disaster scenario is not appropriate. 105 ------- The final implementation problem discussed by the group was the lack of federal consensus in this area. Without such consensus, conflicting guidance from two different agencies will result in implementation problems for those affected, namely the States. Conflicting guidance also contributes to a credibility problem for public officials during the emergency. 7. What problems have been experienced in the application of DCFs or DRLs that require special evaluation or guidance? The discussion of current federal guidance (such as FEMA REP-13) lead the group to conclude that although the PAGs for foodstuffs in this document are workable, the evaluation process is cumbersome and requires a good deal of training to be used effectively. A better approach to implementing the PAGs for contaminated foodstuffs would be a system of pass or fail. The use of individual nuclide specific limits for each foodstuff eliminates much of the need for special guidance. The implementation of the PAG guidance endorsed by the group would require a significant amount of evaluation and assessment before the DRLs are determined. If this .vork is performed prior to any accident and incorporated into the appropriate emergency plans, then the implementation should not be too difficult. 8. What problems regarding disposal of contaminated water or food require special evaluation or guidance? The group did not see any particular problems for disposing of contaminated foodstuffs. The contaminated foodstuffs should be put back on the ground where they originally came from. This is no different than the current protocol used for wash water from decontamination operations. The long term disposal issue becomes the contaminated soil. This soil could be allowed to decay, plowed under or treated as low level radioactive waste where it would be dug up and disposed of in a licensed facility. 9. What problems have been experienced in the implementation of ingestion PAGs for special population groups? The issue of special population groups was discussed in the first sections. If the single nuclide specific limits for each foodstuff is implemented as discussed, there would be no concern for special population groups because the DRL would provide sufficient protection. If the special population group's food source became contaminated, then an alternative food source could be substituted to prevent a food shortage. If the diet of the special population group deviates far from the basis of the DRLs, (Eskimos instead of the farmer) then a diet 106 ------- specific assessment would be needed to determine acceptable DRLs to meet the PAG. As indicated above, until this assessment is performed, the original DRLs could be used for screening. 10. What problems arise from implementation of relocation and food restrictions simultaneously under separate PAGs? The implementation of relocation and ingestion PAGs simultaneously would not present any problems for most of the population because they will be well below the single set of DRLs proposed for contaminated foodstuffs. The portion of the population not relocated would be potentially exposed to the contaminated foodstuffs and would be subject to the ingestion PAGs. There could be special restrictions on certain members (assume most sensitive) of the relocated population if no locally grown food is available. In this case, the change in diet may require reassessment of the DRLs, not the PAG. As long as the ingestion DRLs are met, the population should have sufficient protection. 11. What problems are associated with the long-term management of food production on contaminated land? What evaluations or guides are needed to resolve these problems? The long term management of contaminated foodstuff would consist of the continued measurement of foods and comparison of those results to the single tier DRLs. Return to routine monitoring of food when de-minimis levels are reached. Depending on the time of year of the accident and the type of crops grown in the contaminated areas, monitoring of foodstuffs could continue for a few years. There may be a need for special studies and sampling of the soil to determine suitability for agriculture. Surface water sources may also require further evaluation to determine their suitability for irrigation, recreation or drinking. Long term studies of radionuclides trapped in river, lake or estuary sediments may also be needed. Any of these studies would provide information needed to make decision on the use, access or need for additional remedial measures. 107 ------- APPENDICES ------- Appendix A Proposed FAO/WHO Levels for Radionuclide Contamination of Food in International Trade Following an Accidental Nuclear Release I. Purpose 1. The aim of this document is to provide to the Codex Alimentarius Commission joint FAO/WHO recommendations to control foods in international trade that have been accidentally contaminated with radionuclides. The goal is to provide a system that can be uniformly and simply applied by government authorities and yet one that achieves a level of public health protection to the individual that is more than adequate in the event of a nuclear accident 2. The levels proposed are based on very conservative assumptions and are intended to be used as values below which no food control restrictions need to be applied. Measured values above these levels are not necessarily of public health concern but should alert the competent food control authorities for the need to assess the potential health detriment II. Background 3. Following the April 1986 Chernobyl, USSR nuclear reactor accident, large amounts of radionuclides were released into the atmosphere and carried by weather patterns prevailing at that time for many thousands of kilometers through Europe and the Northern Hemisphere. At the time of the Chernobyl accident there was a definite lack of comprehensive international guidance on radionuclide contamination and authorities responsible for agriculture, environment, health and trade were unable to take uniform action to control radionuclide contaminated food and feed. Differences between countries on acceptable levels of contamination of food led to confusion and disruption of trade. 4. Compared with background radiation from natural and man-made sources that existed before the Chernobyl accident, exposure to X-rays for medical purposes and other types of radiation exposure, radiation protection experts pointed out that exposure to Chernobyl-related radionuclide contamination would add only a small increment to pre-Chernobyl levels of exposure. Due to the known carcinogenic and mutagenic effects of radiation and varying estimates of increased rates of cancer from Chernobyl-related contamination, many consumers were not reassured by these statements. 5. For about four to six weeks after the Chernobyl accident confusion existed about whether or not to let children play outside, whether or not to plough under leafy green vegetables exposed to heavy fallout and whether or not interdiction of local and international shipments of foods and other agricultural products was warranted. Most countries that were directly affected by radioactive fallout from Chernobyl took significantly different and usually less restrictive approaches to control the levels of radionuclide contamination in food than those countries that were not directly affected. Ill ------- 6. Following the widespread confusion and concern that existed after the Chernobyl accident, FAO, WHO and IAEA took action to provide additional guidance to member countries on appropriate responses to nuclear accidents. Other bodies such as the Organization for Economic Cooperation and Development (OECD) and the Commission of European Communities (CEC) also took action to provide guidance to their member countries. The International Commission on Radiation Protection (ICRP) also undertook to review its previous guidance on nuclear accident responses. 7. Shortly after the Chernobyl accident, the Director-General of FAO called on the FAO Secretariat, working in close collaboration with WHO and IAEA, to develop limits for radionuclide contamination for foods in trade which could be accepted by the FAO/WHO Codex Alimentarius Commission and utilized by FAO and WHO member countries to assure orderly trade in foods in the event of accidental contamination with radionuclides. The FAO Secretariat commenced this work through preparation of papers examining various aspects of the problem, which were reviewed by the December 1986 FAO Expert Consultation on Recommended Limits for Radionuclide Contamination of Foods. This Consultation included food control, radiation protection, and safety experts from several countries. The recommendations of the FAO Expert Consultation were transmitted by the FAO Director-General in January 1987 to all FAO member countries, all United Nations agencies and to all other known interested parties so that the FAO recommendations could be used as interim guidance in controlling foods in international commerce until all consult? ^ons and final recommendations were available from FAO, WHO and IAEA. 8. The FAO Expert Consultation Report and recommendations were introduced into the Codex Alimentarius Commission approval and recommendation process by requesting the Codex Committee on Food Additives and Contaminants (CCFA) to consider the FAO report in its March 1987 meeting, prior to the June-July 1987 Session of the Codex Alimentarius Commission (CAC). The CCFA reviewed and generally endorsed the FAO Expert Consultation report, commended FAO on its rapid action, and requested FAO and WHO to convene a Codex Working Group prior to or during the June-July CAC Session so that Codex member countries could include appropriate expertise in their delegations to consider the FAO Report in depth before any action by the CAC. A Working Group was scheduled as requested by CCFA to meet during the CAC session but was subsequently cancelled at the request of WHO which suggested postponing the CAC review until after WHO had completed its work on developing guideline values. The June-July 17th Session of the CAC took note of the CCFA recommendations, commended FAO for providing the only available international recommendations for radionuclide contamination in foods in trade and urged speedy completion of the WHO work so that a joint FAO/WHO approach could be reviewed for approval by the CAC Executive Committee in its July 1988 session. 9. The FAO December 1986 Expert Consultation utilized food control principles to uniformly allocate the total amount of radioactivity from a dose of 5 millisieverts (5 mSv) over 100% of the food consumed. The FAO Expert Group assumed that all foods would be contaminated and utilized the most sensitive population group and body tissue in making its recommendations. On this basis, the group recommended interim international radioactivity action levels in foods which were considerably lower than those recommended by other groups. The FAO interim values were not signiflcantly different from some national levels and those adopted by the Commission of European Communities (CEC) soon after the Chernobyl accident. 112 ------- 10. In assessments of acceptable contamination levels made by WHO, IAEA, OECD and the European Community Article 31 group in 1986-1987, approaches tended to concentrate on radiation protection and safety principles rather than food control and food law procedures. The dose level of 5 mSv was accepted by most groups as a basis for calculation. However, differences of assumptions about the percentage of food supply that might be contaminated and about which dose conversion factor should be used usually resulted in higher contamination levels than the FAO interim levels. 11. During late 1986 and 1987 WHO engaged several consultants and held a preliminary meeting in April 1987 to prepare the WHO recommended health-related approach to radionuclide contamination in foods. In September 1987, WHO held an expert consultation in Geneva and also invited participation of FAO, OECD, IAEA, ICRP and the Commission of the European Communities (CEC). The WHO Expert Consultation provided a methodology and guideline values which could be used by national authorities as a basic for setting their own levels. The reference level of dose was accepted as 5 mSv and food consumption was normalized to a hypothetical intake of 550 kg/y. The potentially contaminating radionuch'des were divided into two main classes, the actinides such as Plutonium 239 and all others such as Caesium 137. Only food groups that were consumed in quantities greater than 20 kg/y were used in the calculation of the guideline values, and special values for infants were developed. Additivity of radionuclides contaminating one or more food groups was accommodated. These values, while assisting member states to develop their own levels, were considered too complex and unsuitable for application to international trade in food. 12. In January 1988, the WHO Executive Board urged the Director-General to continue to cooperate with FAO in developing uniform recommendations on maximum levels regarding radionuclides in food moving in international trade for consideration and adoption by the Codex Alimentarius Commission. 13. The principles applied to the control of contamination of foods moving in international trade are similar to those used in national food control legislation. These have been successfully applied by the Codex Alimentarius Commission in making recommendations about environmental contaminants such as lead, cadmium and mercury in food, and are the basis for current work on the establishment of guideline levels for aflatoxins. These food protection principles are based on the utilization of safety factors which assure the consumer of wide margins of safety beyond the basic levels derived from known health and toxicology research data. At the same time they provide national food control authorities with simple and uniform levels which can be applied to all foods moving in trade, whatever their origin, and whatever their destination in the distribution chain after clearance by control officials. 14. In most countries, national food law prohibits sale or shipment of food contaminated with poisonous or deleterious substances. However, it is recognized that certain low levels of contaminants are unavoidably present in food and maximum levels for their occurrence have to be set to protect the safety of food supplies to all consumers. In arriving at a contaminant level, toxicological data on test animals are reviewed, and a series of conservative assumptions and safety factors are applied in setting the contamination level to be used for regulatory food control purposes. If a no-effect level has been demonstrated in controlled animal feeding tests, that level is the departure point for applying conservative assumptions and safety factors to arrive at a much lower contamination level for foods for human consumption. For contaminants such as radionuclides or 113 ------- mycotoxins where a no-effect level cannot be established, additional considerations are applied in setting contaminant levels which acknowledge the impossibility of avoiding all inadvertent contamination of foods with these substances. 15. The FAO Expert Consultation in December 1986 recommended interim limits for radionuclides in food. At that time, these were regarded as interim levels which would probably need revision at a later date as a result of the experience gained from the Chernobyl accident. It is recognized that both the FAO and WHO guideline values require specific knowledge of the profile of contamination and are not necessarily applicable to the control of future unknown accidental contamination through existing food control legislation. 16. It is therefore necessary to develop values that can be readily applied to future accidents under existing food control legislation. HI. Derivation of Values 17. On examination, the approaches of WHO and FAO, and indeed of other organizations, are basically similar. They all assume a reference level of dose (usually 5 mSv) a total average food consumption rate, a dose per unit intake factor for various radionuclides and a patterr of food consumption, and calculate the levels by the following formula: RLD Level = m x d where RLD = Reference Level of Dose (Sv) m = mass of food consumed (kg) d = dose per unit intake factor (Sv/Bq) 18. Controlling radionuclide contamination of foods moving in international trade requires simple, uniform and easily applied values. This approach is one that can be uniformly applied by government authorities and yet one that achieves a level of public health protection to individuals that is considered more that adequate in the event of a nuclear accident. 19. In making these joint FAO/WHO recommendations the following assumptions have been made in calculating the levels: 1. 5 mSv has been adopted as the reference level of dose for an accident. This value, for most radionuclides, is the committed effective dose equivalent resulting from ingestion in the first year after an accident. Owing to the extremely conservative assumptions adopted, it is most unlikely that the application of the following levels will result in a dose to an individual greater than a small fraction of 1 mSv. 2. 550 kg of food is consumed in a year, all of which is contaminated. 114 ------- 3. Dose per unit intake factors for the radionuclides of concern (1311, 137Cs, 134Cs, 90Sr, and 239Pu) can be conveniently divided into three classes and applied to the general population: (a) those with a dose per unit intake of 10~6 Sv/Bq such as 239Pu and other actinides; (b) those with a dose per unit intake factor of 10~7 Sv/Bq such as 90Sr and other beta emmitters; and (c) those with a dose per unit intake factor of Itt8 Sv/Bq such as 134Q, 137Cs, and 1311. 20. Applying these assumptions to the above formula, the level for the general population for the radionuclides in the 10"5 Sv/Bq group would be: 5 x IP'3 = 909 Bq/kg 550 X which can then be rounded to 1000 Bq/kg. For the actinides this value would be 10 Bq/kg, as the dose per unit intake factor is 100 times larger, and for the radionuclides in the 10"7 Sv/Bq class (such as 90Sr), it would be 100 Bq/kg. 21. It is recognized that the sensitivity of infants may pose a problem if the dose conversion factor for the general population were applied to them indiscriminately. WHO, in its document Derived Intervention Levels for Radionuclides in Food7, proposed separate guidelines for infants. The values were based on an infant consumption of milk of 275 L/y and the specific dose conversion factors for infants for 90Sr, 1311, and 137Cs. The resulting WHO Guidelines values were: 90Sr 160 Bq/L 1311* 1600 Bq/L 137Cs 1800 Bq/L * The value for 1311 was based on a dose of 50 mSv to the thyroid and a mean life of ingested 1311 of 11.5 days. ^-Derived Intervention Levels for Radionuclides in Food. Guidelines for application after widespread radioactive contamination resulting from a major radiation accident. WHO, Geneva, 1988. 115 ------- 22. However, the dose per unit intake factors for infants ingesting alpha-emitting actinides have recently been revised upward and as a prudent measure, a dose per unit intake factor of 10~5 Sv/Bq for these radionuclides has been applied to infants consuming milk and infant foods. 23. To reflect the infant's sensitivity, 1311 has been assigned a dose per unit intake factor of 10"7 Sv/Bq, putting it in the same class as 90Sr. 24. For infant foods and milk the application of these dose per unit intake factors results in a level of 1 Bq/kg for the alpha emitters of the actinide series and any other radionuclide with a dose per unit intake factor of 10'5 Sv/Bq, and 100 Bq/kg for 90Sr and 1311 or any other radionuclides assigned a dose per unit intake of 10"7 Sv/Bq. 25. By infant foods is meant a food prepared specifically for consumption by infants in the first year of life. Such foods are packaged and identified as being for this purpose. 26. The proposed levels are tabulated below: FOODS DESTINED FOR GENERAL CONSUMPTION DOSE PER UNIT INTAKE FACTOR (Sv/Bq) W6 io-7 10-* REPRESENTATIVE RADIONUCLIDES 241Am, 239Pu 90Sr 1311, 134Cs, 137CS LEVEL (Bq/kg) 10 100 1000 27. For infant foods and milk a dose per unit intake factor of 10~5 Sv/Bq is used instead of the W6 Sv/Bq value and 1311 is assigned to the 10~7 Sv/Bq class of radionuclides. MILK AND INFANT FOODS DOSE PER UNIT REPRESENTATIVE LEVEL INTAKE FACTOR RADIONUCLIDES (Bq/kg) (Sv/Bq) 1(T5 241Am, 239Pu 1 Iff7 1311, 90Sr 100 10'8 134Cs, 137Cs 1000 NOTES: As the proposed levels have extensive conservative assumptions built in, there is no need to add contributions between dose per unit intake groups, and each of the three groups should be 116 ------- treated independently. However, the activity of the accidentally contaminating radionuclides within a dose per unit intake group should be added together if more than one radionuclide is present Thus, the 1000 Bq/kg level for the IGr8 Sv/Bq dose per unit intake group is the total activity of all contaminants assigned to that group. For example, following a power reactor accident, 134Cs and 137Cs could be contaminants of food, and the 1000 Bq/kg refers to the summed activity of both these radionuch'des. 28. The levels suggested are designed to be applied only to radionuclides contaminating food moving in international trade following an accident and not to the naturally occurring radionuclides which have always been present in the diet. 29. Both FAO and WHO have called attention in their expert meeting reports to special consideration which might apply to certain classes of food which are consumed in small quantities, such as spices. Some of these foods grown in areas affected by the Chernobyl accident fall-out contained high levels of radionuclides following the accident. Because they represent a very small percentage of total diets and hence would be very small additions to the total dose, application of the suggested levels to products of this type may be unnecessarily restrictive. FAO and WHO are aware that policies vary at present in different countries regarding such classes of food and suggest that further Codex Alimentarius Commission consideration should be given to a more uniform approach to harmonize international trade practices for minor dietary components, no matter what the contamination may be. 30. These levels are intended to be applied to food prepared for consumption. They would be unnecessarily restrictive if applied to dried or concentrated foods prior to dilution or reconstitution. Further Codex Alimentarius Commission consideration should be given to the policy to be adopted when dealing with any contaminant of such foods. 31. By an accident is meant a situation where the uncontrolled release of radionuclides to the environment results in contamination of food offered in international trade. 117 ------- Appendix B Official translation from Russian Accident in the Southern Urals on 29 September 1957 by B.V. Nikipelov, G.N. Romanov, L.A. Buldakov, N.S. Babaev, Yu.B. Kholina and E.I. Mikerin To a very great extent, the negative attitude towards nuclear power which has arisen in certain sectors of our population can be explained by the inadequate information that has been provided concerning the activities of nuclear fuel cycle facilities. This involves questions relating to the construction of new nuclear power plants, and also a comparison of their effects on the environment with those of more traditional industrial undertakings such as thermal power stations, chemical enterprises and metallurgical plants. We are concerned here, furthermore, with information on accidents that have occurred in plants belonging to the nuclear industry and the consequences of those accidents. In the years immediately following the Second World War a military installation was set up in the southern Urals to produce a completely new type of weapon, nuclear weapons in fact, which were needed to strengthen the defensive capacity of our country. With a truly heroic and superhuman effort on the part of the Soviet people, under extremely difficult conditions including conditions which had a deleterious effect on the health of the staff this nuclear shield was created. During the first few years of operation no experience was available with facilities of this kind, and problems affecting the environment and the health of personnel had not yet been studied in a scientific manner. As a consequence, certain parts of the territory surrounding the facility were contaminated during the 1950s. Very serious radioactive contamination resulted from an accident which occurred on 29 September 1957. Owing to a fault in the cooling system used for the concrete tanks containing highly active nitrate-acetate wastes, a chemical explosion occurred in these materials and radioactive fission products were released into the atmosphere and subsequently scattered and deposited in parts of the Chelyabinsk, Sverdlovsk and Tyumensk provinces. The radioactivity released amounted altogether to about 2 million Curies (1 Ci = 3.7 x W10 Bq; the Chernobyl accident released 50 million Ci). The composition of the material released is indicated in Table 1. For the area with a 90Sr contamination density of 0.1 Ci/km2 (double the level of global fallout), the maximum length of the deposition track under the radioactive plume formed reached 300 km; for 90Sr contamination density of 2 Ci/km2 it reached 105 km, with a width of 8-9 km. The area density distribution is shown in Table 2. The presence of gamma emitters among the contaminating nuclides was responsible for the external irradiation of the population and the environment. During the initial period the dose rate 119 ------- was about 150 /iR/h (1 R = 2.58 x 10 coulomb/kg) in the area with a 90Sr contamination density of 1 Ci/km2 Owing to radioactive decay of the short-lived nuclides, contamination levels and gamma dose rates in the area of the accident fell off fairly rapidly during the first few years after formation of the cloud track (see Table 3), and subsequently the radiation situation was governed entirely by the presence of strontium-90 and its rate of radioactive decay. The exposure of the population in the contaminated territory was due in the first instance to external irradiation from the soil and from objects in their dwellings including their own clothing and also to internal irradiation due to the consumption of contaminated food and drinking water and inhalation of activity at the time when the cloud was being formed. Subsequently (after half a year to a year) internal exposure from contaminated food was predominant. The radiation protection measures adopted for the population were as follows: Evacuation of the population; Decontamination of some portions of the agricultural land; Monitoring of contaminated levels in agricultural products and rejection of produce with activity levels exceeding the accepted norms; Limitations imposed on the utilization of contaminated land; and Reorganization of agriculture and forestry, with the creation of specialized state farms and forestry enterprises operating in accordance with the special recommendations worked out in the light of the accident. The dynamics of the evacuation exercise for persons living in regions with a 90Sr contamination density above 2 Ci/km2 are shown in Table 4. In the immediate aftermath of the accident - that is, within 7 to 10 days six hundred persons were evacuated from the settlements in the most severely affected area; and about ten thousand persons were evacuated in the 18 months following the accident. Altogether 10,180 persons were evacuated. Maximum average exposure doses preceding evacuation reached 17 rem in external exposure and 52 rem in effective dose equivalent (150 rem to the gastrointestinal tract). Decontamination consisted mainly in ploughing under the surface layers of agricultural land. In 1958 and 1959 about 20,000 hectares of land at the head end of the cloud track were ploughed under in the usual way and in 1960-1961 deep ploughing was carried out on 6200 hectares of land, in the course of which the contaminated surface layers were turned under to a depth of more than 50cm. A regime for limiting the use of contaminated areas and the access of the population to such areas was introduced immediately after the accident at the head end of the cloud track, and after completion of the evacuation in 1959 this regime was extended to the entire region with a 90Sr contamination density in excess of 2 Ci/km2; this region was then subjected to special sanitary 120 ------- protection regulations. Subsequently, in 1962, this zone was reduced to 220 km2, with a maximum 90Sr contamination density of 100 Ci/km2 at the far end. The rest of the territory was returned to agricultural use. In 1958, 59,000 ha were removed from agricultural use in Chelyabinsk province and 47,000 ha in Sverdlovsk province. Beginning in 1961, these lands were gradually returned to agriculture. In Chelyabinsk six special state farms were set up, and in the Sverdlovsk region three such farms; in the latter region, agricultural production was restored in 1961. In Chelyabinsk province the restoration of lands to agricultural use was virtually completed by 1978, and by now 40,000 ha out of a total of 59,000 have been returned to agriculture. The work of the specialized state farms is carried out in accordance with special scientific and political regulations developed for the purpose7 and is concentrated primarily on the production of meat as a product with minimum 90Sr levels by comparison with other foodstuffs. For economic reasons the specialized state farms do yield other products as well, but where contaminated lands amount to 10-15% of the total agricultural land available to the farms, this land is used exclusively for the production of cattle and pig fodder. Levels of contamination of meat and milk on the specialized state farms of Chelyabinsk province are shown in Table 5. The effectiveness of this agricultural system, evaluated on the basis of the reduction in 90Sr levels brought about in the produce of the specialized state farms by comparison with the levels in "unregulated" agricultural produce, amounts to factors of 2-7 for meat production and 3-4 for milk. However, these figures cannot be applied to the produce of individual farms. Non-evacuated population continued to live in areas with an average maximum 90Sr contamination density of around 1 Ci/km2. The main exposure pathway for these people after the initial period following the accident was ingestion of strontium-90 with food, in particular milk (as much as 60-80%); strontium-90 is deposited in the skeleton, with consequent irradiation of bone and red bone marrow. After thirty years, the daily intake of strontium-90 with food by these members of the population had dropped by a factor of 1300 in comparison with the initial period of the accident, and by a factor of 200 compared with 1958. This was due to the fact that strontium-90 concentrations in milk and other products fell off more quickly than would be expected from the isotope's decay rate (by factors of as much as 110 over thirty years) owing to physico-chemical processes which transformed the strontium in the soil, as well as other natural processes. The annual limit on intake of strontium-90 for a limited sector of the public, namely 0.32 /xCi/year under NRB-76/87 [the 1987 radiation safety standards] was exceeded at a contamination density of 1 Ci/km2 over the first four years following the accident. At present the annual strontium-90 intake for members of the population living in areas with a contamination density of 1 Ci/km2 averages 3% of the permissible annual intake, the largest value being 12% in one settlement. 1The relevant recommendations were formulated by experts of the Experimental Station set up by the USSR Ministry of Medium Mechanical Engineering in 1958 to study the consequences of the accident. This work was carried out in co-operation with the local branch of the Institute of Biophysics of the USSR Ministry of Health. 121 ------- After thirty years in areas with a maximum average 90Sr contamination density of 1 Ci/km2, the effective dose equivalent was 1.2 rem, of which about 2.5 rem affected the red bone marrow and about 8 rem the bone. If we take a dose limit of 0.5 rem per year for exposure of the red bone marrow, the aggregate exposure over thirty years was 2.5: (0.5 x 30) = 0.17 of the permissible limit under NRB-76/87. This evaluation could well be increased by a factor of two, however, in view of the uncertainties in the formation of irradiation pathways. In addition to studying matters of health and safety and the ecological situation that had arisen in the areas affected by the radioactive cloud, special medical brigades performed therapeutic and diagnostic tasks among the local population and carried out a public information campaign aimed at ensuring the best possible approach to radiation hygiene. This latter campaign consisted largely of propaganda for personal hygiene aimed at preventing the uptake of radionuclides in human beings, confiscation of foodstuffs contaminated beyond acceptable levels and in the replacement of those foodstuffs by pure uncontaminated products. In the first stage of the accident an effort was made to interrupt the food chain at the fodder-growing and stock-raising level: this was during the autumn and winter. Interruption of the food chain at the soil-fodder-crop-growing level was carried out in a second stage, during the spring and summer of the following year when radionuclides were reaching living organisms with the new harvest. The main steps taken at this stage were deep ploughing of the radionuclides and careful monitoring of fodder and of food for human conr ^mption. Deep ploughing-under of the soil was started in the late autumn of 1957, but was carried out to a large extent in the summer of 1958. This was a measure which reduced the gamma dose by a factor of ten. These should not be considered as radical measures. Although they made it possible to reduce the uptake of radioactive materials by human beings by a factor of more than ten, the radiation burden to internal organs was reduced by no more than a factor of two. This was due to the composition of the radionuclide mixture in the fallout from the accident. Other clean-up measures also proved to be inadequately effective, especially as decontamination, owing to the special geographical characteristics of the region, produced comparatively poor results. Medical surveillance of the population was carried out in the following manner. The zone affected by radioactive contamination was mapped out and the population living in that zone was transferred, stage by stage, to localities free of radioactive contamination (see Table 4). In all the inhabitants of the region - those who were resettled and also those who lived on the boundary of the resettlement zone, i.e. the region with contamination levels lower than 1 Ci/km2 (90Sr), and persons living further from the boundary of the contaminated zone a number of health indicators were studied: these included general physical state, blood formation (haemopoiesis), neurological status, the development of children, the condition of new-born infants and their physical development, the development of allergies, the condition of the gastrointestinal tract, the incidence of infectious illnesses, and infant mortality. During the first three years after the accident these studies were carried out once a year and in the subsequent period once every ten years. The investigations are continuing at the present time with a view to finding any malignant tumours that have developed as well as other similar afflictions, and to establishing the causes of death among persons who spent a short time in either the contaminated region or in control areas. 122 ------- These dynamic population studies have revealed the following. During the first three years the resettled population and groups living in the area with 90Sr contamination levels above 2 Ci/km2 (see Table 6) exhibited no excess over control groups of specific symptoms such as radiation sickness in any of its forms, nor were there any instances of bone marrow depression or any organic neurological changes or cases of allergy development. There was, further, no manifestation of any increased frequency of vegetative-vascular disorders, myocardial infarction, hypertonic states or any similar disorders. Furthermore, although in 21% of the persons investigated - out of a total of more than 5000 individuals at certain times - a reduction in the leukocyte count in the peripheral blood was found on one occasion, there was rarely any reduction in the thrombocyte count and equally rarely any functional neurological disorders. The external gamma dose among this group of people amounted to anywhere from 0.7 to 17 rem, and the effective dose equivalent to 2.3-52 rem. The main dose, for example, was three to four times greater than the permissible effective dose equivalent to the gastrointestinal tract during the first year owing to the presence of "non-absorbable" radionuclides in the fallout mixture. Special attention has been given to what is the most strongly indicative and most sensitive criterion of both the health and safety situation and the ecological state of the environment, a criterion which reacts rapidly to radiation - namely infant mortality, i.e. deaths among children aged less than one year. The investigations were conducted among the inhabitants of areas affected by the cloud, among persons living in areas with a 90Sr soil contamination density of less than 1 Ci/km2 (control group number 1) and among persons living in regions remote from the boundaries of the cloud track (control group number 2). As can be seen from Table 7, even against the background of very high infant mortality in those years, it was not possible to detect any aggravating influence of enhanced radiation levels on this indicator. A certain excess of infant mortality in the second control group was due to high frequencies of pneumonia and disease of the newborn. As we know, the theoretical assumption that anomalies may often occur in the offspring of irradiated parents has given rise to a great deal of apprehension. Investigations aimed at clarifying this effect were carried out in the period 1980-1987, i.e. at a time when the radiation doses received as a result of the accident were bound to have had their full effect not only on the first but on the second generation of persons subject to the action of radiation. The resultant data are presented in Table 8. This information, based as it is on a large volume of data, appears to confirm that the radiation levels we have been discussing have no effect on the appearance of congenital defects, or on mortality from such defects, in individuals irradiated in the first and second generations following an accidental release of radioactive fission products. Investigators all over the world have been particularly interested in the development of malignant tumours as a result of exposure to ionizing radiation at any and all doses. The idea that such tumour formation is possible relies on the hypothesis of a linear development of cancerous growths which has no threshold. However, an analysis of the incidence of such disease, and of the causes and levels of mortality from malignant neoplasms, carried out over decades, has indicated no significant difference between irradiated and unirradiated populations as far as the incidence of such illness and the structure and level of mortality are concerned (see Table 9). 123 ------- Table 9 encompasses mortality levels from all types of cancer. It will be seen, in the first place, that there are no differences in mortality depending on the place of residence of the persons concerned. Secondly, with time, in the USSR as in the world as a whole, and also in areas affected by the radioactive cloud, mortality from malignant tumours is increasing the consequence of a general worsening of the ecological situation in the world. The role of radioactive contamination and doses of ionizing radiation against the generally unfavourable background is so small as to be scarcely detectable. The radiation levels built up following the events of 1957 are well below the limit which, in the light of all the realistic factual evidence available to us, could be considered as significant - in other words below a dose of 50 rem. Even this level, in terms of effective dose equivalent, was received by only a limited number of people (see Table 4), and in this population no meaningful deviations in the structure of illness have been detected up until now. The scientific investigations which have been carried out since 1957 on the territory affected by the radioactive cloud in the Urals have yielded data of fundamental theoretical and practical importance: Information relating to the spatial and temporal distribution of radionuclides in terrestrial and aqueous ecosystems, and to the behaviour of radionuclides in the food chains of land and water animals; Information relating to the dynamics of formation of the radioactive cloud, the time required for the plume to become established, the stability of the plume, its redistribution in space and time, and so on; The paths by which dose burdens to man, natural organisms and communities were formed in the acute period and in the longer term; Biochemical and biophysical turnover of radionuclides; The biological effects of radiation observed in natural organisms and in members of the population; Forecasts of root and non-root uptake of radionuclides in crops and livestock, and measures to reduce the levels of radioactive contamination; and Organization of safe and rational methods applicable to agriculture, forestry, water bodies, and fish and game culture in the areas affected by radioactive contamination. Possibilities for the reorientation of public and individual farm production. Arrangements permitting agricultural production without the necessity of any special agrotechnical or zootechnical measures in areas with the following degrees of radioactive contamination: 5 Ci/km2 - grain, hay, natural grasses; up to 10 Ci/km2 - milk, seed grasses, silage crops; up to 25 Ci/km2 beef, root plants; up to 50 Ci/km2 - fodder grain crops; and up to 100 Ci/km2 - pork, potatoes, fodder grain crops for processing, seed grasses, seed grains. The scientific investigations carried out from 1957 onwards made it possible to establish a reliable long-term prognosis for the development of the radiation situation following the Chernobyl 124 ------- accident, to predict the biological effects of the accident on various elements of the environment, to develop practical recommendations for reducing the negative consequences of the Chernobyl accident on agriculture, forestry, and on land- and water-based wildlife in the parts of the Ukraine affected by radiation and also in parts of the Gomel' and Mogilev provinces of the Byelorussian SSR. The work of the radioecologists in the Urals is being continued in this direction. The experience obtained in managing the radioecological and radiation-hygiene consequences of the Chelyabinsk and Chernobyl accidents has been used in the preparation of a "Guide to the Planning and Implementation of Measures Designed to Reduce the Negative Radiological and Radioecological Consequences of Accidents Going Beyond the Design Basis Accident and Involving Releases of Radioactivity to the Environment", which, once it has been approved by the state regulatory bodies, will be used when necessary by undertakings in the nuclear and nuclear power industries. 125 ------- Table 1 Radionuclide 89Sr 90Sr 4- 90Y 95Zr + 95Nb 106Ru + 106Rh 137Cs 144Ce + 144Pr 147Pm 155Eu 239,240Pu Characteristics of the radionuclide mixture released in the Contribution to Half-life Type of total activity radiation of the mixture, emitted traces 51 d ft, T 5.4 28.6 y /3 24.9 65 d 0, T 3.7 1 y ft, 7 0.036 30 y 0, T 66 284 d 0, 7 traces 2.6 y /3, T traces 5 y /J, T traces - a Table 2 Area and population of the contaminated region Density of radioactive contamination, Area of the Ci/km2 (90Sr) region, km2 > 0.1 including: > 2 > 100 > 15,000 1,000 120 accident Nature of radiological hazard Internal irradiation (skeleton) External irradiation External External and External Population of the region (x 103) ~ 270 10 2.1 internal 126 ------- Table 3 Dynamics of the radiation situation Time after accident, years 0 1 3 10 25 Contamination density Gross activity (relative units) 1 0.34 0.10 0.043 0.029 90Sr, Ci/km2 0.027 0.026 0.025 0.021 0.014 Table 4 Gamma dose rate (relative units based on initial value) 1 5.6 x 10'2 8.2 x lO'3 9.8 x 10-* 3.8 x 10-* Dynamics of population evacuation and of exposure dose to the population before evacuation Population group and size (x 103) I: 0.60 II: 0.28 III: 2.0 IV: 4.2 V: 3.1 Total: 10.18 [*] Average contam- ination density, Ci/km2 (90Sr) 500 65 18 8.9 3.3 Time required for evacuation, days exposure 7-10 250 250 330 670 Average dose received up to evacuation, rem External Effective dose eq. 17 14 3.9 1.9 0.68 52 44 12 5.6 2.3 [*] Following the Chernobyl accident 115,000 persons were evacuated. 127 ------- Table 5 90Sr concentrations in the meat and milk of cattle during the period 1965-1988 Indicator 1965- 1970 1971- 1975 1976- 1980 1981- 1985 1986- 1988 Meat (beef) 1. Specialized state farms Observed concentration, pCiykg Normalized (permissible) concentration, (pCi/kg)/(Ci/km2) Milk Observed concentration, pCi/L Normalized concentration, (pCi/L)/(Ci/km2) 2. Privately held cattle Observed concentration, pCi/L Normalized concentration, (PCi/L)/(Ci/km2) 0.59 12 0.45 6.8 33 32 210 220 0.27 3.7 28 23 110 110 0.097 1.8 18 15 140 150 12 12 130 140 128 ------- Table 6 Observed changes in the health of individuals living in areas with a contamination density of 2 Ci/km2 (by comparison with control groups) Syndrome Frequency of occurrence (% of patients investigated) Radiation sickness (all forms) Bone marrow depression Reduced leukocyte count in blood Reduced thrombocyte count Functional neurological disturbances Organic neurological changes Allergy development None observed None observed 21 A few cases A few cases None observed None observed Table 7 Mortality among infants aged < 1 year per 1000 births in areas affected by the plume Causes of mortality All causes Nutritional disorders Pneumonia Infectious illnesses Disease of the newborn Plume track 27.7 15.2 1.7 1.6 8.7 Control No. 1 31.4 12.2 3.1 2.3 13.8 Control No. 2 38.6 5.1 16.1 3.0 14.5 129 ------- Table 8 Mortality of newborn infants with innate developmental defects (per 1000 live births) In the whole of the In Chelyabinsk In Sverdlovsk affected zone, including province province the plume track 0.95 +/- 0.08 1.0 +/- 0.08 1.1 +/- 0.07 Table 9 Mortality due to malignant neoplasms (per 100,000 inhabitants) In the whole of Period of the affected zone, In Chelyabinsk In .Sverdlovsk research including the province province plume track 1970-1980 145.8 146.6 1980-1987 160.7 167.6 159.4 130 ------- |