Both of these are capable of doing damage to tissues. However, K is not very radioactive, having a half-life of 1. What is the actual risk of eating a banana? A banana contains about mg of potassium, and when eaten exposes the consumer to about 0. For comparison, a chest x-ray delivers 10 mrem. In other words, for death to ensue, a million times a thousand, or a billion, bananas would have to be consumed.
And that would have to be at one sitting. Quite a challenge. But what about the risk of eating bananas over a lifetime? Cumulative damage? Some potassium is always taken in via the diet, and some is always excreted, meaning that there is no buildup of radioactive potassium.
So, while bananas are indeed radioactive, the dose of radioactivity they deliver does not pose a risk. It also gives you four mrem per year. The song says diamonds are a girl's best friend, but they' re also a radiation source of up to 0. Some, like Zircon, are naturally radioactive, while others are bombarded with neutrons to enhance their color. Even where you live can cause the Geiger counter to click. Aberdeen , Scotland is famous as the Granite City and all the radionuclides expose the inhabitants to mrem per year.
If you live in a brick house, that's 1. But the worst in our homes is radon gas, which seeps out of the earth and collects in basement areas to give the residents a whopping mrem per year. If you have an old television or computer monitor, you might want to swap it for a flat screen. That will save you 1 mrem per year in X-rays.
Oddly enough, the one thing you would think would be a major source of radiation isn't. Most home smoke detectors use a particle of radioactive americium to ionize smoke particles. Total dosage? A miserly 0. A much larger source of radiation is the person sleeping next to you. Lying there sweating and breathing, they expose you to 2 mrem per year.
If that make you want to sleep on the couch, remember that you emit 40 mrem per year. If you have ceramic caps or false teeth, add another 0. Travel broadens the mind, but it also ups the radiation doses. Every security scan is worth 0. So far, so scary, but how to put all of this into perspective? As we said, it's estimated Americans are on average exposed to a total of mrem per year.
To give a point of comparison, a lump of uranium would give you a dose of 1, mrem per year. That's over twice normal exposure, but uranium is mainly an alpha emitter with some weak gamma rays thrown in, so you'd have to carry it in your pocket full time to be at risk. According to Professor Gerry Thomas , a radiation expert from the Department of Surgery and Cancer at Imperial College London, radiation is something much less to be feared than is popularly believed.
If you measured radiation levels in Aberdeen, which is built on granite, there would be higher background levels of radiation than in Fukushima. According to the NRC, a 3 mrem dose increases the chances of premature death by one in a million. That's equivalent to breathing New York City air for two days, riding a motorcycle for one mile, riding in a car for miles, eating 40 tablespoons of peanut butter at once, eating 10 charbroiled steaks, or smoking one cigarette. Even famous catastrophes have turned out to be less disastrous than thought from a radiation perspective.
Thomas says that being exposed to the direct radiation of the Hiroshima explosion was less dangerous than being obese. As for the worst nuclear disaster in history at Chernobyl in , though 43 people died as a direct result of the accident, 4, others exposed have shown no ill effects. In addition, the surrounding area has been turned into a wildlife preserve and, though the radioactive fallout has certainly affected the flora and fauna, some experts note the overall effect is less than that of a forest fire or chemical pollutants with none of the feared mutations resulting in little more than animal stillbirths.
Part of the problem with assessing the effects of radiation is that while extreme cases like nuclear weapon attacks, or accidents like Chernobyl or Fukushima lend themselves to straightforward analysis, small doses are much harder to study. This is because large doses of radiation produce obvious symptoms and prognoses, but small doses soon descend into an ocean of complicated causes and effects.
Taking a hypothetical example, someone is exposed to a small dose of radiation, then later on develops cancer. Did the radiation cause it? Did it increase the likelihood of cancer? If so, by how much? Or was the cancer due to smoking, diet, occupational hazards, heredity, congenital defects, or a combination of these? Did the radiation make this worse or did it have no effect at all?
Because there are so many possible causes and the human body has a limited ability to recover from radiation, these are very hard questions to answer. Because of these uncertainties, scientists since the s have adopted the no safe minimum dose standard. Since there aren't enough people exposed to harmful levels of radiation and no way to create a control group, the most conservative approach was taken, which was to extrapolate backwards from the severe cases at Hiroshima and Nagasaki based on the assumption that no dose of radiation, however small, was safe.
The world has come a long way from a century ago when almost nothing was known about radiation. That was a time when radium was used to make luminous watch dials and eventually sparked a major scandal when the women who painted the radioactive solution on the watch hands came down with radiation poisoning from ingesting the paint. It was also a time when radium was looked up as a miracle cure and all manner of nostrums, from "radium" inhalers to "radium" water, could be bought over the counter.
Today, we have a better grasp of what everyday radiation involves. We have a better understanding of how much surrounds us on a daily basis and the risks involved. But it isn't a recipe for complacency. Rather, it's one for education and continued vigilance. Radiation is not the mysterious force of science fiction, but it's still very dangerous. But the most important thing is to keep a sense of perspective. True, radiation is all around us, but the hazards it poses to our lives are so slight it can't be measured with any certainty.
And there many other hazards that are more immediate. Let's put it this way. Don't worry about dying of radiation poisoning from eating too many bananas — you'd have to eat at a sitting to do yourself harm, and you'd be dead of potassium poisoning or indigestion long before the radiation hurt you. If you are curious as to what your annual radiation dose might be, the NRC has a calculator here.
LOG IN. Menu HOME. Search Query Submit Search. By David Szondy. Facebook Twitter Flipboard LinkedIn. Radiation may be frightening, but we live with a surprising amount of natural radiation every day. View 8 Images. A plug of highly enriched uranium. A surprising number of foods are naturally radioactive. Potatoes also contain radioactive isotopes. Uranium gives uranium glass, also known as Bohemian glass, its distinct color.
The Chernobyl reactor being fitted with its new containment dome. Tags Science Education Radiation. David Szondy. David Szondy is a freelance journalist, playwright, and general scribbler based in Seattle, Washington. A retired field archaeologist and university lecturer, he has a background in the history of science, technology, and medicine with a particular emphasis on aerospace, military, and cybernetic subjects.
In addition, he is the author of a number of websites, four award-winning plays, a novel that has thankfully vanished from history, reviews, scholarly works ranging from industrial archaeology to law, and has worked as a feature writer for several international magazines.
The irradiated food does not come into contact with radioactive materials, and food irradiation does not make food radioactive. Learn more about Food Irradiation. In the case of a radiological event, there may be situations in which an animal ingests materials that contain radioactivity. For example, if radioactive materials are found in water, some fish may ingest them, which, in turn, could be eaten by a human as part of their diet. To ensure the protection of the public, the U.
Food and Drug Administration FDA tests food in the United States for contaminants, including radiation, and sets strict limits and restrictions on foods imported from other countries. Natural radiation in food does not require any special actions because the radiation levels are extremely low. The FDA oversees the safety of many consumer products, including most foods, drugs, vaccines, cosmetics and tobacco products. This oversight extends to ensuring the safety of these imported products as well.
Human Foods This webpage provides an overview of requirements for foods imported into the United States. Recalls, Outbreaks and Emergencies This webpage provides links to resources about food recalls, emergencies or import alerts. Natural Radioactivity in Food: Experts Discuss Harmonizing International Standards This webpage provides information about harmonizing international guidance regarding acceptable levels of natural radioactivity levels in food.
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