Guarding Against Radiation
Every single day of our lives, we are exposed to both environmental and man-made radiation.
Protecting ourselves from the effects of radiation exposure should not only be considered a matter of life or death in the event of a nuclear disaster. Every time we go to the doctor for an X-ray, every time we use our cellular phones and computers, every time we go out under the sun, we expose ourselves to different kinds of ionizing and non-ionizing radiation.
We are exposed to low levels of radiation from different sources every single day. Background radiation may be natural (from cosmic rays and naturally occurring environmental radioactive isotopes) or artificial (from our cellular phones, microwave ovens, medical equipment, and radiation produced by nuclear power stations and nuclear weapons use).
And considering that the growing body of evidence shows that the effects of radiation exposure are cumulative so that it does not matter anymore how small the exposure is, we must seriously endeavor to do what we can to protect our body from DNA damage.
Types of Radiation
Ionizing Radiation
“Radiation is often categorized as either ionizing or non-ionizing depending on the energy of the radiated particles.” ( Source: wikipedia.org )
Ionization occurs when electrons are knocked off of atoms and molecules, thereby creating ions.
Ionizing radiation has an energy signature that is high enough to cause ionization, as well as break chemical bonds. Ionizing radiation is known to cause greater biological harm because the process of ionization directly damages DNA, increasing the risk of cancer and genetic damage.
We are constantly exposed to radioactive materials that are naturally present in our environment and which are classified as ionizing radiation. The concentrations are often small enough that special instruments, such as a Geiger counter, are needed to detect them.
The greatest health risks, however, are posed by ionizing radiation produced by man-made technologies, such as certain medical equipment and nuclear weapons and reactors.
In addition to being at high risk for cancer and genetic damage, exposure to high doses of ionizing radiation causes acute radiation syndrome (ARS), which is characterized by “skin burns, hair loss, internal organ failure, and death.” ( Source: wikipedia.org )
Ultraviolet radiation, x-ray, and cosmic radiation are the most common examples of ionizing radiation.
Non-Ionizing Radiation
Non-ionizing radiation has a lower energy and longer wavelength signature. Unlike ionizing radiation, non-ionizing radiation does not have enough energy to knock off electrons (causing ionization).
Biological damage from non-ionizing radiation only occurs when the “intensity is high enough to cause excessive heating.” The browning of food during broiling is a good example of how tissue reacts to the excessive heat of infrared radiation, a type of non-ionizing radiation. ( Source: wikipedia.org – Radiation )
Certain types of non-ionizing radiation, however, still have the capability to break chemical bonds and, therefore, cause biological damage even when they don’t have enough energy to cause ionization.
Ultraviolet light (the lower part of the ultraviolet radiation spectrum), visible light, infrared light, radio waves, and microwave are the most common examples of non-ionizing radiation.
The Science
In terms of lifetime, daily exposure, is there such a thing as a safe threshold for radiation exposure?
Now and then, we hear or read reports about the health risks associated with radiation exposure from some source or another. Guidelines for radiation safety have been established for exposure to radioactive substances delivered in high doses over a short period of time (acute) and exposure to radiation in low doses over an extended period (chronic).
However, both are based only on findings from studies and actual events involving acute radiation exposure.
Little is known about the actual health risks associated with chronic exposure to background radiation, and much less about the combined and cumulative harmful effects of background and artificial radiation.
How Much Radiation is Safe?
Even if you lived inside a lead house, there is no way to avoid background radiation.
Natural sources of radiation include cosmic rays, the air, the earth’s crust, building materials, and even food. And then there are the artificial radiation sources that increase the amount of background radiation humans are exposed to. The largest contribution of artificial radiation comes from medical equipment. Other sources include nuclear weapons use and the radioactive wastes produced by nuclear power stations.
The total radiation exposure from all natural sources averages to 0.3 cGy (centigray; gray is the SI unit for absorbed dose of radiation) per person, per year. (http://web.mit.edu/newsoffice/2012/prolonged-radiation-exposure-0515.html)
According to the Environmental Protection Agency’s website page on Radiation Protection ( www.epa.gov ), the type or severity of health effect caused by radiation exposure is influenced by the duration and amount of exposure.
Low-level radiation exposure over a long period of time (chronic exposure) causes stochastic health effects, such as cancer and DNA mutations. High-level radiation exposure over a short period of time (acute exposure) causes non-stochastic health effects, such as radiation poisoning/radiation sickness and radiation burns.
Given the conditions of exposure that lead to non-stochastic health effects, determining the thresholds at which varying levels of damage are caused is relatively straightforward.
“Safe” exposure thresholds for radiation sources that lead to stochastic health effects, on the other hand, can be tricky to identify because most of these sources emit radiation levels that are less than natural background radiation levels and, thus, are difficult to detect and measure.
With regards to stochastic health effects, the EPA presupposes on the side of caution that an increase in radiation exposure will also increase health risks.
To protect the public from exposure to all radiation sources, the EPA has set an exposure limit of under 100 mrem for any specific source, which is far below levels of exposure that are known to cause non-stochastic health effects. Health physicists have set an exposure limit from all sources other than background radiation of about 100 mrem per year.
Chernobyl Dispersion
Fukushima Dispersion
Certain Short-Term Levels Are Safe?
There are other experts, however, who believe that at certain levels, radiation exposure is safe and any health effects are only short-term, even when the exposure occurs over a long period.
Until recently, there have been no studies that measured the long-term effects of low-dose, sustained radiation exposure. On the other hand, there have been plenty of real-world data from past nuclear disasters, as well as from scientific studies, that show the serious effects of high-dose radiation delivered all at once.
Until recently, there have been no studies that measured the long-term effects of low-dose, sustained radiation exposure.
A new study from the Massachusetts Institute of Technology (MIT) was the first to test the widely accepted assumption that prolonged and sustained exposure to low-dose radiation can cause genetic damage. ( http://web.mit.edu )
The researchers, led by Bevin Engelward and Jacquelyn Yanch, used radioactive iodine to expose mice to a total dose of 10.5 cGy spread out over a period of five weeks; this dose is 400 times more than background radiation levels and the radioactive iodine emitted radiation similar to that produced by Japan’s Fukushima reactor when it exploded.
Background radiation already causes spontaneous DNA damage, but effective DNA repair systems fix this damage within the cells in a timely manner. At the end of five weeks, the researchers found no DNA damage in the mice. And they believe that even if the radiation exposure continued past five weeks, the said radiation amount will still not cause any significant DNA damage that can’t be fixed by the existing DNA repair systems.
Doug Boreham, a medical physics and applied radiation sciences professor at McMaster University, comments on the findings: “Now, it’s believed that all radiation is bad for you, and any time you get a little bit of radiation, it adds up and your risk of cancer goes up. There’s now evidence building that that is not the case.” ( http://web.mit.edu )
Estimates for radiation safety involving low-dose radiation exposure over a long period of time had been arrived at using data from acute radiation exposures. Guidelines for evacuation during a nuclear accident and to establish safe radiation levels in the workplace, for example, are based on these estimates.
According to current U.S. regulations, in the event of a nuclear accident, residents should be evacuated when radiation levels in their area increase to eight times more than background levels. ( http://web.mit.edu )
The study findings indicate that these estimates, while erring on the side of caution, are too conservative. These radiation safety guidelines for artificial radiation exposure ensure that exposure is kept to a minimum so that health effects are also minimized.
No Such Thing As Safe Levels Of Radiation
In fact, many medical experts believe that there is no such thing as safe levels of radiation exposure. Which side do you want to error on?
One study, The Biological Effects of Ionizing Radiation, conducted by the National Academy of Sciences arrived at the conclusion that “radiation is a direct linear relationship [of] dose to damage, and that every dose of radiation has the potential to cause cancers.” ( http://environment.about.com )
Some medical experts, however, believe that no matter how small the level of exposure is, damage to health from regular and prolonged exposure is cumulative; this means the adverse effects build up over time and the risks progress from insignificant to serious.
Citing the Chernobyl nuclear disaster as a case in point, radiation expert Dr. Jeff Patterson, former president of Physicians for Social Responsibility, said, during a panel discussion at the National Press Club in D.C. last March 2011 following the nuclear disaster in Japan, that even 25 years after Chernobyl, many people are still eating mushrooms that are high in radioactive Cesium and animals are still not safe to be slaughtered for food for the same reason. “And so this does, indeed, go on and on. It’s one thing to say in a brief picture that there’s no damage. It’s another thing to look at this over 60 or 70 or 100 years, which is the time length we have to follow this.” ( http://environment.about.com )
How to Mitigate the Effects of Radiation
Healthy eating is one of the most effective ways that we can mitigate the harmful biological effects of radiation exposure.
So what foods should we load up on to protect us from harmful radiation and get rid of radioactive residues?
Foods rich in Beta Carotene. Loading up on green, leafy vegetables and red, orange, and yellow fruits and vegetables will help boost our immune system and protect tissues from damage caused by radiation exposure.
Foods high in Pectin. Pectin is a type of polysaccharide (carbohydrate) found in the cell walls of plants. Pectin has the ability to bind to other compounds, including radioactive residues, in the bloodstream and tissues and expel them from the body through the urine and/or feces. Organic apples, plums, guavas, oranges, and other citrus fruits are rich in pectin.
Foods rich in Chlorophyll. Spirulina, alfalfa, chlorella, and many leafy greens are chlorophyll-rich foods. The antioxidants in chlorophyll are especially effective in getting rid of free radicals, decreasing radiation toxicity, and neutralizing/detoxifying poisonous substances, such as cadmium, uranium, lead, mercury, and copper.
Foods rich in Minerals. High concentrations of potassium and calcium are extremely beneficial to the thyroid gland, which is often severely affected by radiation exposure of any kind. Fish and poultry, as well as bananas, raisins, figs, potatoes, nuts, and seeds should always be a diet staple. Other mineral-rich foods are tomatoes, squash, lima beans, beets, and avocados.
Seaweeds. Seaweeds are loaded with sodium alginate and iodine, both of which significantly reduce the absorption of radioactive substances by the body and help in their elimination, thereby protecting the body from radiation poisoning.
Foods high in Nucleotides. Great options include anchovies, sardines, and other whole fish; nucleotides help reinforce the integrity of our DNA.
Other foods that we should always include in our diet to help fight the effects of radiation exposure include healthy oils, fermented foods, probiotics, foods rich in phytonutrients, and garlic.
Are There Safe Levels Of Radiation?
Perhaps, in a pristine environment, one that has remained untouched by modern man and his technologies, and one whose naturally existing radiation we have already adapted to over the millions of years of our evolution.
These days, however, there is no escaping the harmful radiation that is of our own making. But with a commitment to healthful living, specifically through healthful eating, it is still possible to guard against the dangers of radiation. Θ
