The Banana Equivalent Dose of catastrophic nuclear accidents

The 'Nuclear for Climate' lobby group recently attended the United Nations' COP23 climate conference armed with bananas, in order to make specious comparisons between radiation exposures from eating bananas and routine emissions from nuclear power plants.

One of the reasons the comparison is specious is that some exposures are voluntary, others aren't. Australian academic Prof. Barry Brook said in the aftermath of the Fukushima disaster: "People don't understand that they live in an environment that is awash with radiation and they make decisions every day which affect their radiation dose - they hop on an airplane or eat a banana or sit close to the TV.'' True - but people choose to hop on an airplane or eat a banana or sit close to the TV, whereas radiation doses from nuclear plants and nuclear accidents are usually involuntary.

Another reason why the comparison made by 'Nuclear for Climate' is specious is that it ignores spikes in radioactive emissions during reactor refueling. Radiation biologist Dr Ian Fairlie notes that when nuclear reactors are refueled, a 12-hour spike in radioactive emissions exposes local people to levels of radioactivity up to 500 times greater than during normal operation. The spikes may explain infant leukemia increases near nuclear plants − but operators provide no warnings and take no measures to reduce exposures.

The comparison between bananas and nuclear power plants also ignores the spike in emissions and radiation doses following catastrophic accidents. So, what's the Banana Equivalent Dose (yes, that's a thing) of the Chernobyl and Fukushima disasters?

According to the International Atomic Energy Agency (IAEA), the collective effective dose from Chernobyl was 600,000 person-Sieverts. The UN Scientific Committee on the Effects of Atomic Radiation estimates radiation exposure from the Fukushima disaster at 48,000person-Sieverts.

Combined, exposure from Chernobyl and Fukushima is estimated at 648,000 person-Sieverts. Exposure from eating a banana is estimated at between 0.09-2.3 microSieverts. Let's use a figure of 0.1 microSievert per banana. Thus, exposure from Chernobyl and Fukushima equates to 6,480,000,000,000 Banana Equivalent Doses - that's 6.48 trillion bananas or, if you prefer, 6.48 terabananas or 6,480 gigabananas.

End-to-end, that many 15-cm (6-inch) bananas would stretch 972 million kilometres - far enough to reach the sun 6.5 times over, or the moon 2,529 times over.

Potassium cycle

Another reason the comparison made by 'Nuclear for Climate' is specious is explained by Dr Gordon Edwards from the Canadian Coalition for Nuclear Responsibility:

"[T]he body already has a lot of "natural" potassium including K-40 [which is unavoidable], and any new "natural" potassium ingested is balanced by eliminating a comparable amount of "natural" potassium to maintain the "homeostasis" of the body. In other words the body's own mechanisms will not allow for a net increase in potassium levels – and therefore will not allow for an increase in K-40 content in the body.

"Here's what the Oak Ridge Associated Universities has to say; (ORAU was founded in 1946 as the Oak Ridge Institute of Nuclear Studies.): 'The human body maintains relatively tight homeostatic control over potassium levels. This means that the consumption of foods containing large amounts of potassium will not increase the body's potassium content. As such, eating foods like bananas does not increase your annual radiation dose. If someone ingested potassium that had been enriched in K-40, that would be another story.'

"The same argument does not work for radioactive caesium, or for any of the radioactive pollutants given off by a nuclear power plant, because most of these materials do not exist in nature at all – and those that do exist in nature are not subject to the same homeostatic mechanism that the body uses to control potassium levels. Consequently any foodstuffs or beverages containing radioactive caesium or other man-made radioactive pollutants will cause an additional annual dose of ionizing radiation to the person so exposed."

Likewise, Linda Gunter explained in a 16 November 2017 article:

"At the COP23 Climate Talks currently underway in Bonn, a group calling itself Nuclear for Climate, wants you to slip on their false banana propaganda and fall for their nonsensically unscientific notion that bananas are actually more dangerous than nuclear power plants! I am not making this up. Here is the picture.

"The oxymoronic Nuclear for Climate people are handing out bananas complete with a sticker that reads: "This normal, every-day banana is more radioactive than living near a nuclear power plant for one year." ...

"If you smell something rotten in this banana business, you are right. So let's peel off the propaganda right now. In short, when you eat a banana, your body's level of potassium-40 doesn't increase. You just get rid of some excess potassium-40. The net dose of a banana is zero.

"To explain in more detail, the tiny radiation exposure due to eating a banana lasts only for a few hours after ingestion, namely the time it takes for the normal potassium content of the body to be regulated by the kidneys. Since our bodies are under homeostatic control, the body's level of potassium-40 doesn't increase after eating a banana. The body just gets rid of some excess potassium-40.

"The banana bashers don't want you to know this and instead try to pretend that the potassium in bananas is the same as the genuinely dangerous man-made radionuclides ‒ such as cesium-137 and strontium-90 ‒ that are released into our environment from nuclear power facilities, from atomic bomb tests and from accidents like Fukushima and Chernobyl.

"These radioactive elements, unlike the potassium-40 in bananas, are mistaken by the human body for more familiar elements. For example, ingested radioactive strontium-90 replaces stable calcium, and ingested radioactive cesium-137 replaces stable potassium. These nuclides can lodge in bones and muscles and irradiate people from within. This is internal radiation and can lead to very serious, long-lasting and trans-generational health impacts."

An unfortunate incident in Goiania, Brazil in September 1987 illustrates the hazards of cesium-137, a fission product. Two people stole a radiotherapy source from a disused medical clinic. A security guard did not show up to work that day; he went instead to the cinema to see 'Herbie Goes Bananas'. The radiotherapy source contained 93 grams of cesium-137. It was sold to a junkyard dealer. Many people were exposed to the radioactive cesium and they spread the contamination to other sites within and beyond the town. At least four people died from exposure to the radiation source and, according to the IAEA, "many others" suffered radiation injuries. Those injured included eight patients who required surgical debridments, amputation of the digital extremities and plastic skin grafts. The incident was rated Level 5 ('Accident with Off Site Risk') on the 7-point International Nuclear Event Scale.

Terrorists don't arm themselves with bananas

There is a long history of nuclear power plants being used directly and indirectly in support of nuclear weapons programs. Bananas are of no interest to nuclear weapons proliferators. There's no Treaty on the Non-Proliferation of Bananas, no Comprehensive Test Banana Treaty, no Anti-Banana Missile Treaty. Kim Jong-un and Donald Trump aren't threatening each other with bananas; not yet, at least.

Nuclear historian Paul Langley notes that terrorists don't arm themselves with bananas:

"The potassium cycle in humans is no excuse for nuclear authorities anywhere on the planet to claim any benefit or natural precedent for the marketing of nuclear industry emissions contaminated food.

"The fission products are not nutrients. Do not eat them. The nuclear industry promises to keep its radioactive sources sealed. When the industry invariably fails in this undertaking, it turns around and claims that the residue of its pollution is like a banana. Crap. The residue is like the residue of a rad weapon. Fact. It's the same stuff. Terrorists do not attempt to arm themselves with bananas. They are not dangerous.

"Radio Strontium, Radio Iodine, Radio cesium have NO PLACE in food. Nuke is not clean, it is not green and it relies on lies it has concocted over decades. ... The more the nuclear industry claims eating plutonium, strontium, cesium, iodine and other fuel and fission products is OK because bananas exist and because the potassium is a needed nutrient, the more I consider them to be blatant liars."