The Fukushima radiation dose is not something we should be worried about from a public health standpoint.

In short;

1L of Fukushima water is equivalent to 13 bananas or 2 Brazil nuts.

— Me, 2021

And;

If you drank 2L of Fukushima water a day, you would increase your annual radiation dose by about 15%. You would do worse by moving to Cornwall. In Cornwall the annual natural radiation dose is more than three times the UK average.

— Me, 2021

And finally;

If all the radioactivity in the entire Fukushima inventory were ingested by a single person, this person would have a 50% chance of surviving and living the rest of his life with an elevated risk of cancer.

— Me, 2021

Discharge of radioactive water

Since the 2011 Fukushima Daiichi nuclear disaster, the nuclear plant has accumulated 1.25 million tonnes of waste water, stored in 1,061 tanks on the land of the nuclear plant. According to the Friends of the Earth, strong critics of the water release plan on April 13, 2021, the government plans to release a quantity of water containing 22 trillion becquerels of tritium per year into the ocean. A Becquerel (Bq) is a measure of ‘radio-activity’.

A Becquerel (Bq) means that in a given substance, 1 atom is splitting each second.

When each of these radioactive atoms split, they release a ray of radiation. If a ray of radiation is absorbed by a human, it will deposit its energy in the body and damage the DNA in certain cells.

The amount of damage this radioactivity can cause in humans is related to the energy released by the radiation ray when it is absorbed, the type of radiation ray (Alpha, Beta or Gamma) and the human organ which it is absorbed into as some are more vulnerable than others. This measure of radiation damage is known as the ’effective dose’ and measured in a unit called Sieverts (Sv). It takes 4.5 Sv to give someone a 50% chance of dying within 30 days. This is known as the LD50.

You calculate the effective dose, by times-ing the radioactivity (22 TBq) by the dose per unit radioactivity (between 22 and 23 Sv/TBq, as defined by the United States Environmental Protection Agency (EPA) in 1982). So, if all of this dose were somehow were ingested by humans, each year the total ingested dose would equal between 1 and 10 Sieverts. Let’s take the central value, say 5 Sv.

A Sievert (Sv) is a measure radiation dose accounting for the effectiveness of the type of radiation and organ. More than 4.5 Sv is required to probably die within 30 days.

So, even if all this radioactivity were ingested by a single person, this person would have a 50% chance of surviving and living the rest of his life with an elevated risk of cancer.

But no one can drink thousands of tonnes of water, and this water is so diluted before discharging it into the sea, and again diluted in the sea itself. In fact, it is so dilute even before it reaches the sea that is it would not be considered radioactive under any normal circumstance. According to the Japan Times in 2018 There was about 850,000 tons of water in total (with a concentration of 60,000 Bq/L of tritium in the most radioactive water). This means that the average radioactivity concentration is only 1.32 μSv/L.

We know that there is about 0.1 μSv per Banana. In fact, this is a standard measurement. Therefore, 1L of tritiated water is equivalent to 13 bananas.

Eating Brazil Nuts however is far more radioactive. For example , they contain Radium (Ra-228) at a concentration of 0.18mSv/kg (180μSv/kg). Therefore, 1L of tritiated water is Equivalent to 7g grams of Brazil nuts. Which is approximately 2 Brazil nuts.

1L of Fukushima water is equivalent to 13 bananas or 2 Brazil nuts.

— Me, 2021

The average human drinks 700L/year. Therefore, even if you directly attached your home water pipes to the discharge, you likely get a dose of less than 1 mSv. In the average year, the average person receives 7mSv. So, it would increase your annual dose by about 15%.

If you drank 2L of Fukushima water a day, you would increase your annual radiation dose by about 15%. You would do worse by moving to Cornwall. In Cornwall the annual natural radiation dose is 7.8 mSv which is more than three times the UK average.

— Me, 2021

Review of Spurious Fallout-Cancer claims

Lets read the [WHO’s review of cancer report in 2013]((https://www.who.int/mediacentre/news/releases/2013/fukushima_report_20130228/en/) This assesses the estimated first year doses and makes an estimate of the much lower predicted lifetime doses. It predicts that for populations living in the most affected areas there is a:

  • 70% higher risk of developing thyroid cancer for girls exposed as infants (I.e. under 1-year-old) (the risk has risen from a lifetime risk of 0.75% to 1.25%), 
  • a 7% higher risk of leukaemia in males exposed as infants, (the risk has risen from a lifetime risk of 0.7% to 0.75%),
  • a 6% higher risk of breast cancer in females exposed as infants and; 
  • a 4% higher risk, overall, of developing solid cancers for females.

Most affected were locations within Fukushima prefecture (outside the 20 km evacuation zone) where doses were likely to be among the highest of those received by the general population;

This includes:

  • Namie Town — 2010 Population 20,905
  • Iitate Village — 2010 Population 6,209

For a Total 2010 Population of 27,114.

Applying the national average age distribution of 55,000 <1-year-olds in a population of 127.8 million, you discover that this 0.4% of the population and hence 110 infant girls and 110 infant boys.

So according to this prediction if you apply the percentage cancer risks in the exposed population, discover: 

  • For the infants girls there is now a 15.4% chance that at least one of them will get thyroid cancer in their lifetime rather than a 9.1% chance. Thyroid cancer has a 98% survival rate;
  • a 7% higher risk of leukaemia in males exposed as infants;
  • a 6% higher risk of breast cancer in females exposed as infants and;
  • a 4% higher risk, overall, of developing solid cancers for females.

Now for the doses. And when reading this, the average radiation dose for a normal human being, like you, on planet earth is: 7mSv per year.

Even for the most affected in Namie town, they estimated them to have only received average first year organ doses of between 21 and 27mSv,approximately half the US radiation worker limit. Lifetime average doses for these organs in subsequent years were predicted as less than 0.1mSv. 

Medical Radiography Doses are frequently given to children without public controversy. In fact, medical radiography doubles the annual radiation exposure of the population as a whole.

  • A Positron Emission Tomography-Computed Tomography(PET-CT) Whole Body Protocol provides a dose of 22.7mSv.
  • A Spinal CT scan provides 8.8mSv.
  • A Chest CT is 6.1mSv
  • An Upper GI Study or a Barium Enema are 6mSv each.
  • A simple chest X-Ray is 0.1mSv.
  • A dental x-ray is 0.005mSv

The Fukushima radiation dose is not something we should be worried about from a public health standpoint.

TODO

Compare cancer risk from:

  • silica dust in building industry
  • air pollution