Following the devastating earthquake and tsunami, Japan is now facing a nuclear crisis with the failure of several nuclear power plants. Because of the potential impact on health, some basic knowledge of radiation and its effects on the human body will be helpful. This handout also provides information on what to do in a nuclear emergency. FACTS ABOUT RADIATIONWhat is Radiation?Atoms are the basic building blocks of all matter. Some atoms contain excess energy, and tend to seeka more stable state by emitting this energy as radiation. While most types of radiation cannot bedirectly felt, light and heat are common forms of radiation that we can directly experience.Radiation is not new and is not limited to nuclear power plants. Our environment contains manysources of radiation. Some of these are natural: the Sun, radioactive rocks and metals, etc.; whereasothers are artificial: X-ray machines and microwave ovens, to name a few. Nuclear power plants useradiation to convert water to steam, which then drives turbines to generate electricity.Contamination & Radiation“Radioactive contamination” refers to the unwanted or unintended presence of radioactive substanceson ordinary material. Food, water, or air is considered to be contaminated if it contains more ordifferent types of radioactive material than would normally be present. Our bodies naturally containtrace amounts of the radioactive elements potassium-40, carbon-14 and tritium (hydrogen-3).However, we are not considered to be contaminated because these elements exist within us naturally.On the other hand, the presence of iodine-131 in food, air or water may be indicative of contaminationfrom leakage of radioactive material. The radiation from contaminants may be harmful if the levels arehigh enough and the exposure lasts long enough.How contamination occursRadioactive particles released into the air can be inhaled just by breathing normally; these particlescould fall on fruits, vegetables or grains which then enter the food chain. Dairy cows and goats couldalso eat contaminated grass and pass it along the food chain to humans. Contaminated water (fallingas radioactive rain, or pooling in open catchment areas) can similarly enter the water cycle and beingested. More information can be found here: http://www.bt.cdc.gov/radiation/contamination.asp
IN A NUCLEAR EMERGENCYPeople may be exposed to radioactivity released during an accident in the following ways:o By direct radiation exposure from the source (irradiation)o By breathing in radioactive dust (inhalation)o By exposure from radioactive materials carried in the air and deposited on surfaces (contact)o By eating and drinking food and water contaminated with radioactive materials (ingestion)The potential health effects of exposure to radiation are dependent on various factors such as theabsorbed dose (amount of energy deposited in the body), the ability of the radiation to harm humantissue, and which organs are affected. Radiation sickness, typically manifesting as nausea and vomiting,generally follows an acute, large exposure. Symptoms tend to appear sooner and become more severeas the dosage/exposure of radiation increases, and this is associated with a poorer chance of survival.Early symptoms of radiation sickness Mild exposure Moderate Severe exposure Very severe exposure exposureNausea and vomiting Within 6 hours Within 2 hours Within 1 hour Within 10 minutesDiarrhea -- Within 8 hours Within 3 hours Within 1 hourHeadache -- Within 24 hours Within 4 hours Within 2 hoursFever -- Within 3 hours Within 1 hour Within 1 hourLater symptoms of radiation sicknessDizziness and -- -- Within 1 week ImmediatedisorientationWeakness, fatigue Within 4 weeks Within 1-4 weeks Within 1 week ImmediateHair loss, bloody vomit -- Within 1-4 weeks Within 1 week Immediateand stools, infections,poor wound healing,low blood pressureSecondary Source: Adapted from "Bushberg JT. Radiation exposure and contamination. The Merck Manuals: The MerckManual for Healthcare Professionals" and "Upton AC. Radiation injury. In: Goldman L, et al., eds. Cecil Medicine. 23rd ed.Philadelphia, Pa.: Saunders Elsevier; 2007." (The table should be used for indicative/general reference only. When in doubt, seek medical advice.)
Exposure to doses less than that which cause serious radiation sickness can still cause long-term healthproblems; if the exposure is prolonged, there is also a possibility of cancer developing, as thecumulative effects of radiation cause increasing cell damage and genetic mutations. More informationon Acute Radiation Syndrome (ARS) is available here: http://www.bt.cdc.gov/radiation/ars.aspWhat to do in an emergency In the event of an accident involving the possible release of radioactive material, the following actions may be taken to reduce exposure. Remember - keep calm. Panic is the greatest enemy in any emergency. A list of items to consider preparing can be found here: http://www.bt.cdc.gov/radiation/shelter.asp Sheltering - This provides protection from inhalation of, and contact with, radioactive material. Stay indoors. Close all doors and windows. Turn off all air conditioners, ventilation fans, furnaces, and close off sources of air intake. If you must go outdoors, cover your nose and mouth with a handkerchief or mask. If you have been outside, remove all outer clothing (i.e. coats, coveralls, hats, gloves and shoes) before coming in. Put the items you were wearing in a plastic bag, seal it shut, and store it out of the way. Shower immediately, if possible. Put your food in covered containers or in the refrigerator. Do not use the telephone unless absolutely necessary (to avoid straining communication networks). Keep a radio (preferably a hand-powered one, or have spare batteries) with you, tuned to local stations for updates. Do not evacuate unless instructed to. Evacuation - Evacuation reduces exposure by removing people from the affected area. Emergency response officials will tell you if it is necessary to leave your home. Gather clothing and essential items. Check your house to see that all water taps, faucets, lights, the gas supply and appliances are turned off. Close and lock your windows, and lock your door behind you. If you own pets, place them inside with stored food and water if you are not taking them along. Drive safely, keeping all car windows and external air vents closed. Offer to take nearby friends and neighbors who may need a ride. Follow the official evacuation route and other instructions given.
Stable iodine tablets - Radioactive iodine is one of the products that could be released in a serious nuclear power plant accident. Potassium iodide (KI) is a non-radioactive form of iodine that may be taken as tablets. By pre-loading the body with non-radioactive KI, less radioactive iodine will be absorbed by the thyroid gland. KI, however, is only effective against exposure to radioactive iodine and only protects the thyroid gland. KI is not an anti-radiation pill and does not protect against any other form of radiation. It is considered a supplemental protective measure, secondary to sheltering or evacuation. It should only be taken at the direction of public health officials. For more information on KI, please refer to: http://www.bt.cdc.gov/radiation/ki.asp Food - Radioactive material deposited on soil or grass can find its way into food through crops and animals. Consume food and water supplies which you have stocked previously (i.e. before the accident). Keep food in covered containers or in the refrigerator. Do not drink tap water. Unless told to do otherwise: Do not consume locally produced milk or vegetables Do not drink water exposed to the outdoors Do not slaughter animals Do not process or distribute food products Do not fish, hunt or gather mushrooms or other forest foodsSeek medical treatment immediately for any unusual symptoms, such as nausea and vomiting that may be related to radiation exposure. Human Dynamic Contact Details Hong Kong Head Office 10/F, Knutsford 10, Knutsford Terrace Tsim Sha Tsui, HONG KONG Tel: (852) 28543727 | Fax: (852) 25424668 Email: firstname.lastname@example.org | URL: www.humandynamic.com
References: Federal Emergency Management Agency (FEMA): http://www.fema.gov/hazard/nuclear/index.shtm Radiation sickness-overview. University of Maryland Medical Center. http://www.umm.edu/ency/article/000026.htm Raditation sickness – Symptoms. Mayo Clinic. http://www.mayoclinic.com/health/radiation-sickness/DS00432/DSECTION=symptoms Radiation sickness, MedlinePlus Medical Encyclopedia. http://www.nlm.nih.gov/medlineplus/ency/article/000026.htm Emergency Preparedness for a Nuclear Power Station Problem: o Denver: http://www.denvernc.com/nuclear.htm o Orange County: http://san-clemente.org/sc/Inf/EmergencyPlan/WelcomeEmerPlanning/WhitePages_Eva c_2009.pdf o San Luis Obispo County: http://www.slocounty.ca.gov/OES/NPPInfo.htm Nuclear emergencies – Information for the Public: http://www.hpa.org.uk/web/HPAwebFile/HPAweb_C/1272031417941 CDC: http://www.bt.cdc.gov/radiation/factsheets.asp International Atomic Energy Agency: http://www.iaea.org/; http://www-naweb.iaea.org/nafa/about-nafa/index.html