(Facts checked) Man-made nuclear radiation evokes both fascination
and fear.
The nuclear disasters at Chernobyl and Fukushima are good examples of this.
While the meltdown at the Chernobyl power plant caused thousands of nearby residents
to flee their homes in 1986, tourists now flock to the area after watching the HBO series
Chernobyl 33 years later.
Eight years after a large earthquake and tsunami caused a nuclear meltdown at the Fukushima
Daiichi plant, some Fukushima evacuees face an uneasy homecoming marked by mistrust of
government officials and worry whenever their dosimeters detect spikes in radiation.
The Fukushima nuclear disaster has also been the subject of several films, including the
documentaries Nuclear Nation and Fukushima: A Nuclear Story, and a new film is in the
works called Fukushima 50.
Now another place made radioactive by man has attracted media attention.
A Newsweek article recently reported that “some of the Marshall Islands [. . .] have
radiation levels higher than Fukushima and Chernobyl, according to scientists.”
The Marshall Islands in the Pacific Ocean might seem like a tropical paradise, but it
is far from pristine.
Some of the northern Marshall Islands were part of the Pacific Proving Grounds, and the
United States conducted 67 nuclear weapons tests there from 1946 to 1958.
Enewetak Atoll in the Marshall Islands was the testing site of the world’s first hydrogen
bomb in 1952, and the 15-megaton Castle Bravo hydrogen bomb test occurred on Bikini Atoll
in 1954.
The Castle Bravo test resulted in the evacuation of 167 Bikini islanders, who thought their
evacuation was temporary, and a little over 200 Marshallese were exposed to radioactive
fallout in nearby atolls.
The US government has spent millions of dollars to compensate those displaced and injured
by the nuclear testing.
It has also attempted to clean up the radioactive waste left behind by these nuclear tests,
but a study recently published in the Proceedings of the National Academy of Sciences (PNAS)
shows the US government still has a lot more work to do.
For this study, Columbia University researchers measured the external gamma radiation found
in 9 islands in 4 atolls of the northern Marshall Islands affected by nuclear weapons testing.
They took measurements in several islands in the Bikini and Enewetak atolls because
these atolls “were used as ground zero for the tests.”
They also checked gamma radiation levels in islands in Rongelap and Utirik atolls because
they were “affected by radioactive fallout from the largest nuclear test the United States
has ever conducted, the Bravo test held March 1, 1954.”
Most of the measurements were taken in 2015, but additional measurements were made in trips
to these areas in 2017 and 2018.
The results are given in millirems per year (mrem/y), which is a measurement of the dose
equivalent.
The US Nuclear Regulatory Commission (USNRC) states that the “dose equivalent (or effective
dose) combines the amount of radiation absorbed and the medical effects of that type of radiation.”
The USNRC adds that “units for dose equivalent are the roentgen equivalent man (rem) and
sievert (Sv), and biological dose equivalents are commonly measured in 1/1000th of a rem
(known as a millirem or mrem).”
The researchers found that external gamma radiation was highest on Bikini Island in
Bikini Atoll and Naen Island in Rongelap Atoll.
They took a total of 185 measurements on Bikini Island.
In 2015, the lowest and highest external gamma radiation measurements on Bikini Island were
11 mrem/y (0.11 mSv/y) and 648 mrem/y (6.48 mSv/y), and these values did not change after
additional measurements were taken in 2017 and 2018.
However, the mean “for the full data set increased slightly,” rising from 184 mrem/y
to 191 mrem/y.
On Naen Island, they took only 18 measurements.
The researchers reported that “measured values ranged from 34 to 543 mrem/y” or
0.34-5.43 mSv/y.
They added that “Naen has the highest average external gamma radiation levels of all of
the islands we have visited during 3 trips to the northern Marshall Islands (2015, 2017,
and 2018).”
However, they also noted that “large sections of the island were not measured, causing some
uncertainty in the interpolation to those areas.”
To get an idea of just how much radiation is still in the Marshall Islands, we’ll
compare it to radiation from a common radiation source.
According to the CDC, the “typical dose from a chest x-ray” is .01 rem or 10 millirems.
This means that if you were to visit Bikini Island, you would receive about as much radiation
as you would get from one chest x-ray on the low end to about 64 chest x-rays on the high
end.
The mean or average amount of radiation you would receive would be equivalent to about
18 to 19 chest x-rays.
On Naen Island, you would receive radiation that is equivalent to about 3 to 54 chest
x-rays.
The high end figure of 648 mrem/y of gamma radiation on Bikini Island is slightly higher
than the average dose of radiation people living in the US are exposed to each year,
which the CDC states is 0.62 rem or 620 millirems per year, while the high end figure of 543
mrem/y of gamma radiation on Naen Island is slightly lower than this average dose.
While researchers describe the gamma radiation levels found in some parts of the Marshall
Islands as “much higher than those found around the Chernobyl and Fukushima nuclear
accidents” according to one source, this observation is only partially accurate.
Some of the measurements taken in the Marshall Islands are indeed higher than some of the
radiation levels measured at Fukushima.
A 2019 Scientific American article about Fukushima states that “radiation [ . . . ] in some
places continues to measure at least 5 millisieverts (mSv) a year beyond natural background radiation,”
which is equivalent to 500 mrem/y.
But some areas in Fukushima are still more radioactive than the Marshall Islands.
Scientific American reports that “in certain spots, radioactivity is as high as 20mSv”
or 2000 mrem/y.
This level happens to be what one source describes as the yearly limit for occupational exposure
set by the International Commission on Radiological Protection (ICRP).
Like Fukushima and the Marshall Islands, the radiation measurements taken around Chernobyl
vary widely.
According to an infographic from a 2019 BBC news article, current radiation levels in
the Chernobyl exclusion zone range from 0 - 12.07+ microsieverts per hour.
Some parts of Bikini and Naen islands do have more radiation than some of the low radiation
areas in the Chernobyl exclusion zone, such as those with a radiation level of 0.02 microSv/hour
or 17.52 mrem/y.
However, even the highest radiation levels measured on Bikini and Naen islands of 648
mrem/y and 543 mrem/y are no match for a hot spot in the Chernobyl exclusion zone with
a radiation level of 12.07 microSv/hour, which is 10,573 mrem/year.
This amount of radiation is equivalent to the radiation you would receive from about
1057 chest x-rays.
While this is a large amount of radiation, it would take much higher doses of radiation
to cause serious negative biological effects.
According to the CDC, 50 rem (50,000 millirems) of radiation “causes damage to blood cells,”
while 100 rem (100,000 millirems) is the “lowest dose that could cause acute radiation syndrome.”
[show infographic]
Being more radioactive than some parts of Fukushima and Chernobyl is not something positive
to brag about.
And there is more bad news.
Columbia University researchers also measured the concentrations of several radioisotopes
in soil samples taken in the Marshall Islands, including americium-241 (241Am), plutonium-238
(238Pu), 239,240Pu, and cesium-137 (137Cs).
Despite the fact that more than 60 years have passed since nuclear testing ended, researchers
found high concentrations of cesium-137, which is a major source of gamma radiation.
Cesium-137 concentrations were highest in soil samples taken from Enjebi, Runit, Bikini,
and Naen islands.
The researchers observed that a few Naen samples, 1 Enjebi sample, and 1 Runit sample were “all
above” a Japanese Food Sanitation Law limit for cesium-134 and cesium-137 in agricultural
soils.
They also state that these “concentrations are also all above concentrations found in
soil near the Chernobyl power plant less than 10 years after the accident.”
The Marshallese have already experienced firsthand some of the serious negative health effects
of cesium-137.
The EPA states that “external exposure to large amounts of Cs-137 can cause burns, acute
radiation sickness and even death.”
A medical report by Jacob Robbins of the National Institutes of Health and William H. Adams
of Brookhaven National Laboratory documents some of these symptoms in those living in
close proximity to the Castle Bravo test in 1954.
It states that “on Rongelap, about two-thirds of the people developed anorexia and nausea
and one-tenth had vomiting and diarrhea.”
In addition, it describes how “skin burns appeared after 12-14 days in about 90% of
the Rongelap inhabitants, with ulcerations in 15%.”
According to the EPA, internal exposure to cesium-137 produces another effect that the
Marshallese are too familiar with -- increased cancer risk.
In 2010, the National Cancer Institute published a study about the cancer risk for Marshall
Islands residents exposed to radioactive fallout from US nuclear weapons tests.
The authors of the study “estimate that as much as 1.6% of all cancers (about 170
cancers) among those alive between 1948 and 1970 might be attributable to radiation exposures
resulting from nuclear testing fallout.”
Their estimates for people living in Rongelap are much higher because they were exposed
to higher levels of radiation: “For the 82 people who lived on Rongelap atoll, the
authors projected 55% of all cancers might be attributed to fallout exposure.”
A Washington Post article sums up the cancer situation in the Marshall Islands by stating
that “everyone seems to have a relative whose cancer falls on the Energy Department’s
list of ailments traceable to radiation.”
Cesium-37 has a half-life of about 30 years, so people living in the Marshall Islands today
are not being exposed to as much radiation as those who were alive during the time the
tests were conducted.
However, according to Live Science, the “levels on Bikini and Naen islands were so high, they
surpassed the maximum exposure limit that the United States and the Republic of the
Marshall Islands agreed to in the 1990s.”
This limit is 100 millirems per year.
This amount is less than the average dose people in the US receive from naturally occurring
background radiation, which the CDC states is 310 mrem per year.
The results of this study may affect plans to repopulate these islands.
The Columbia University researchers made some recommendations based on these results.
One of them is that “given the lifestyle of people living on remote atolls, it appears
to us that clean-up of Naen, and possibly other northern Rongelap Atoll islands, would
be needed before full atoll resettlement can be envisioned.”
Another recommendation is that “the radiation levels on Bikini Island, which served as the
primary island for habitation on the atoll, before and in the aftermath of the testing,
are too high for relocation to Bikini.”
Newsweek recently reported that Bikini Island is still off-limits to residents because the
radiation is still over the maximum limit: “The average value of background gamma radiation
levels on Bikini was found to be nearly double that limit.
This means residents will not be able to return to Bikini.”
Residents have mixed reactions to the idea of returning to their island homes that are
more radioactive than some parts of Fukushima and Chernobyl.
Some Marshallese, such as 90-year-old Lirok Joash from Bikini island, dream of going back
even though it is not a realistic dream.
In an interview with Aljazeera America, she expressed her ideas in her native language,
so her grandson Alson Kelen translates her words.
“She is trying to say she would like to die and be buried on her homeland,” Kelen
explains, adding: “You and I know that it’s not possible.”
Others who have relocated to other islands or countries never want to return.
The Guardian interviewed one of these “exiles.”
“I won’t move there,” said Evelyn Ralpho-Jeadrik of her home atoll, Rongelap, which was engulfed
in fallout from Bravo and evacuated two days after the test.
“I do not believe it’s safe and I don’t want to put my children at risk.”
And then there are others who focus not on the idea of returning but on other significant
damage caused by being forced to leave in the first place.
One of them is Lani Kramer, a councilwoman in Bikini’s local government.
In an interview with the Guardian, she said, “It is not just their homes that have been
lost, [. . . ] but an entire swathe of the islands’ culture.”
She adds, “As a result of being displaced we’ve lost our cultural heritage – our
traditional customs and skills, which for thousands of years were passed down from generation
to generation.”
Would you visit the Marshall Islands, Fukushima, or Chernobyl, or would the radiation keep
you away?
Let us know in the comments!
Also, be sure to check out our other video Chernobyl Suicide Squad - 3 Men Who Prevented
Even Worse Nuclear Disaster!
Thanks for watching, and, as always, don’t forget to like, share, and subscribe.
See you next time!