USA * KEYWORDS: Contamination - Domestic animals - Emergencies - Radioactivity - Surveillance - United States of America.

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1 Rev. sci. tech. Off. int. Epiz., 1988, 7 (1), USA * Summary: The United States Department of Agriculture has prepared contingency plans in the event of radioactive contamination. Ways of dealing with farm animals (including poultry) and farmland exposed to radiation are discussed. KEYWORDS: Contamination - Domestic animals - Emergencies - Radioactivity - Surveillance - United States of America. The purpose of this paper is to describe US planning efforts concerning the agricultural community in the event of an incident at a fixed nuclear facility, specifically at a commercial nuclear power plant. In addition, it describes what support the US Department of Agriculture (USDA) can provide in the event of a radiological emergency. US PLANNING EFFORTS In the United States, State and local governments have the primary responsibility for protecting the public during a radiological release. State and local jurisdictions and operators of nuclear facilities have compatible radiological emergency response plans which have been coordinated and tested on a biennial basis. Most State and local governments do not have massive emergency response capabilities. Therefore, Federal Departments and Agencies are prepared to assist in the event that there is a potential for significant consequences or in the event that incidents extend beyond several hours. Accordingly, the USDA has developed an extensive Radiological Emergency Response Plan which is periodically tested during exercises and drills and modified as necessary. The USDA plan provides for assistance to State and local governments in two major areas: developing agricultural protective measures and assessing damage. USDA CAPABILITIES During a radiological emergency, the USDA can provide the following support to assist in reducing the impact of a radiological incident on the agricultural community: Animal and Plant Health Inspection Service, P.O. Box 96464, Washington DC , USA.

2 160 Information and assistance to farmers The Department has for many years maintained an extensive information dissemination program in all States. This system can be redirected quickly to communicate radiological emergency information to the agricultural community. Ingestion pathway sampling Local USDA personnel are available to assist the States in agricultural sampling of milk, water, crops, soil, etc. Certification of farmers USDA personnel can also assist State agricultural officials in certifying farmers as emergency workers so that they can gain access to evacuated areas in order to care for livestock. Livestock feed assistance The USDA has a network of nationwide offices that can identify locations of uncontaminated feed through listings which they maintain. Assistance in minimizing food contamination The USDA works closely with other Federal Agencies and State agricultural representatives in developing protective action recommendations and in disseminating information to the agricultural community on the effects of radiation on the food chain. Advice on the disposition of exposed livestock and poultry The USDA has experienced, professional personnel in the area of veterinary medicine who can provide valuable assistance to State and local governments on the disposition of contaminated livestock and poultry. Damage assessment Information on damage to crops, soil, livestock, poultry and processing facilities would be incorporated into a damage assessment report for use in determining the type of assistance needed. Indemnification During an emergency, the US Congress may grant supplemental funds for indemnification based on the severity of the accident. THE INGESTION PATHWAY The USDA response efforts are concentrated on the ingestion exposure pathway, which generally takes into consideration areas within a 50-mile radius of a fixed nuclear facility. The ingestion exposure pathway is affected by the deposition of radionuclides on crops, other vegetation, bodies of surface water, and ground surfaces. Contamination in the ingestion pathway may remain as a long-term problem since the radionuclides in the soil are taken up by vegetation, including vegetables, fruit trees, grain and forage, or by livestock feeding on contaminated pasture. Variation

3 in deposition and uptake within the ingestion pathway may necessitate detailed field testing and tailored protective actions over the long term. These protective actions may require modification of the food production, processing and distribution cycle. The three primary ingestion pathways are milk, other foods, and water. 161 GUIDELINES FOR PROTECTIVE ACTION The US Food and Drug Administration (FDA), Department of Health and Human Services, has published guidelines to determine whether levels of projected radiation doses warrant protective actions with respect to human food and animal feed. The FDA guidelines recommend two levels of protective response: - Preventive protective actions: Protective actions to prevent or reduce contamination of milk and food. The FDA preventive protective action guides are 150 msv to the thyroid and 50 msv to the whole body and other organs. - Emergency protective actions: Actions taken by public officials to isolate food in order to prevent its introduction into commerce and to determine whether condemnation or other dispositions are appropriate. The FDA emergency protective action guides are 1,500 msv to the thyroid and 500 msv to the whole body and other organs. PROTECTIVE ACTIONS IN AGRICULTURE The decision in favor of preventive measures for the ingestion pathway emergency planning zone should only be taken on the basis of verified measurements of deposition or contamination of foods. Following is a list of suggested protective actions that should be considered by emergency responders relative to agricultural products, soil and water: Milk Remove all lactating dairy animals from pasture and place them on uncontaminated feed and water. Meat and meat products If levels of cesium in milk approach the preventive protective action guide response level, provide for surveillance and protective actions such as placing meat animals on uncontaminated feed and water. Poultry and poultry products Monitor poultry if they are raised out-of-doors, especially if they are used for egg production. If poultry live indoors and are fed stored rations, contamination is unlikely. Fruits and vegetables Wash, brush, scrub or peel fruits and vegetables to remove surface contamination.

4 162 Grains Permit grain to grow to maturity, with subsequent milling and polishing to remove most of the remaining radioactive contamination. Soil Should soil problems occur, implement proper soil management procedures such as the following to reduce contamination: - Idling. Idling may be necessary in some cases. In a worst-case situation, however, removal and proper disposal of soil would be more appropriate. - Alternating types of crops. Alternating types of crops may be beneficial in some situations. Crops which contribute little or no radioactive material to the human diet could be substituted for other food crops. For example, fiber crops, such as cotton and flax, might be substituted for fruit and vegetable crops. - Deep plowing. Deep plowing may keep radioactive substances below the plant root zone as they decay. - Liming. Liming may be done to limit absorption of specific radioactive substances by the crops. Water Cover open wells, rain barrels, and tanks to prevent contamination of water supplies. For storage containers filled by runoff from roofs or other surface drain fields, the filler pipe should be disconnected to prevent contaminants from being washed into the storage container. Unless soils are highly permeable, contaminants deposited on the ground will normally travel very slowly into aquifer. Radionuclides may, however, be released directly into surface water bodies and into ground water. Streams and lake currents can transport these radionuclides many miles in a few hours. There are some additional considerations that the USDA incorporates into planning efforts for the agricultural community following a nuclear incident. These include: - Notifying food processors, distributors and farmers of protective actions. - Initiating embargoes, if appropriate. - Using site-specific information for decision making. - Being sensitive to the public. - Deciding if farmers can re-enter contaminated areas. In selecting appropriate protective actions, emergency responders must take into account the amount and type of radionuclides present, the urgency of the situation, the feasibility and utility of the action, and the direct impact on agriculture and the food supply. The consequence of the actions taken should not result in a greater problem than the one being prevented. EDUCATION AND INFORMATION In the United States, emergency planners make provisions for dealing with the informational needs specific to farmers and other participants in the food production

5 process. Recommendations for farmers and food processors are available. Fact sheets have been developed summarizing recommended protective actions for applicable agricultural industries including those of milk, livestock and crops produced for human consumption. The USDA has prepared a booklet for use by the agricultural community as part of the overall information program. Effective rumor control is also a necessary part of providing timely and accurate public information. 163 CHERNOBYL EXPERIENCE During the incident at Chernobyl in the Soviet Union, the USDA provided survey meters, probes and film badges for import inspectors at the ports of entry for monitoring incoming food products from affected countries. Action levels set for meat and poultry products were 55 Bq/kg for 1-131, and 2,775 Bq/kg for Cs-134 plus Cs-137. The level for Cs-134 plus Cs-137 was subsequently lowered to 370 Bq/kg. Samples were also randomly taken and sent to laboratories for further analysis. If contamination exceeded the action levels, the product was not accepted. RECENT FINDINGS Studies on the effects of radiation on livestock conducted by US researchers suggest that farm livestock show no measurable effects from being exposed to radiation unless the level is greatly in excess of the natural background levels. In addition, other research suggests that: - Lactating farm animals tend to be more sensitive and are a primary concern where radioactive material has been ingested. - One of the most effective ways of protecting livestock during and after a nuclear incident would be to place animals on stored feed and covered water or move livestock to uncontaminated pastures. In addition, the washing and rinsing of farm animals would remove most, if not all, of the contamination on surface areas. - Swine animals tend to have the most efficient systems of any traditional farm animal in terms of withstanding and repairing any damage after radiation exposure. - Severe exposure to radiation will temporarily reduce the productivity of most livestock, but the long-term effects on these animals would be small. - Livestock are good screens for humans against undesirable radioactive materials entering human diets; with the exception of the radioisotopes of iodine in milk, very little fission-produced radioactivity would be expected to be transferred through the food chain in livestock products to humans. Considering this fact and the protective action guides that have been developed by the FDA, products which have been exposed to low levels of radioactive material (assuming the product has not been contaminated during processing) should be relatively safe for human consumption. - Poultry are able to withstand the effects of radiation exposure better than any other traditional farm animals. In fact, the nature of the poultry industry in the United States generally reduces the effects of nuclear radiation on both birds and their products. For example, poultry are generally fed covered feed and water and are housed in coops. This alone would reduce the exposure to radioactive contamination quite significantly. In addition, the natural covering of feathers tends to reduce further the actual exposure these animals may receive from a nuclear release.

6 164 - Meat and poultry products which are covered (e.g. packaged, canned, or jarred) will be safe unless exposed to contaminated air or water. Generally, washing of these closed containers will render these meat and poultry products safe to eat. - To date, nuclear power plant incidents (release of radioactive materials) which have occurred within the United States have not caused any consequential damage to livestock, poultry or their products. CONCLUSION In the United States, coordinated emergency response plans prepared by Federal, State and local governments have been completed and are tested and updated periodically for every commercial nuclear power plant. Agriculture planning is a significant part of these plans. The combination of plans and periodic exercises has resulted in a system which can efficiently and effectively respond to a radiological emergency in all segments of the community, including the agricultural community. ÉTATS-UNIS D'AMÉRIQUE. * * * Résumé : Le Département de l'agriculture des Etats-Unis a préparé des plans d'urgence pour faire face à l'éventualité d'une contamination radioactive. Les mesures prévues pour les animaux d'élevage (y Compris les volailles) et les terres agricoles exposés aux radiations sont présentées. MOTS-CLÉS : Animaux domestiques - Contamination - Etats-Unis d'amérique - Radioactivité - Situations d'urgence - Surveillance. ESTADOS UNIDOS DE AMÉRICA. * * * Resumen: El Ministerio de Agricultura de los Estados Unidos ha preparado planes de emergencia para hacer frente a una posible contaminación radiactiva. Se presentan las medidas previstas para los animales de cría (incluidas las aves de corral) y las tierras agrícolas expuestos a las radiaciones. PALABRAS CLAVE: Animales domésticos - Contaminación - Estados Unidos de América - Radiactividad - Situaciones de emergencia - Vigilancia.