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
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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
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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
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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
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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.
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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
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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
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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
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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
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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
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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
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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
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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
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SPEAKERS' PAPERS
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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.
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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
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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.
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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.
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- 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?
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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.
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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
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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.
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-- 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)
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-- 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
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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
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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
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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.
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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.
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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
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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.
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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.
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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.
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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.
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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.
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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.
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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
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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
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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.
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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.
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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
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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
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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
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requires a high degree of organization in the responsible agency in the planning, operating and
control of the response effort.
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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].
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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.
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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:
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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,
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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.
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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
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[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
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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
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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.
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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
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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.
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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
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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.
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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.
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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)
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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
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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.
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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.
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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.
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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.
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SUBMITTED PAPERS
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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
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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.
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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.
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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.
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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
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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.
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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
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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.
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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).
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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.
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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.
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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.
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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?
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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.
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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
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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
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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.
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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.
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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.
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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
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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).
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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.
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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.
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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.
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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.
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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.
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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.
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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
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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.
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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.
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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
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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.
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APPENDICES
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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.
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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.
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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
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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.
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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.
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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
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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.
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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
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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
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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.
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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.
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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).
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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
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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.
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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
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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.
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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
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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
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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
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