Moruroa and Marutea Sud

[Ramona]

The current events in Japan inspired me to look at published studies about the effects of the Tschernobyl desaster. While doing that I stumbled over a recent article about the cancer rates due to French nuclear testing in the Gambiers. One Figure showed the location of two test sites, Mururoa and Fangataufa, which were heavily contaminated in the course of underground and atmospheric nuclear weapon tests during 1966-96. What struck me was the close location to Marutea Sud. I read about the unusually large pearls that can be cultured in oysters from that location and obviously wondered whether contamination of these waters could have influenced the ecosystems in that region.

In particular since fallout from the tests resulted in sometimes high contamination of places such as Samoa and Tahiti. It seems there is still radioactive fission products leeching into the ocean in quite significant amounts. Those would accumulate in the food chain and likely induce genetic changes over time. This, in turn, could influence the fitness of some organisms (positively or negatively) and result in changes to the ecosystem. It seems the French went to great lengths to suppress any testing of people or the environment. At least I could not find much scientifically sound published information. Does anybody know of significant changes in the ecosystem in that region and could that explain why Robert Wan?s oysters are bigger than in other places? I could only find hints that ciguatera is endemic now on Moruroa, but nothing on other organisms. Also, does anybody have more information on the effect on health of the workers or the general population?

My reading materials:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2965871/

http://books.google.com/books?id=hA...&resnum=6&ved=0CDUQ6AEwBQ#v=onepage&q&f=false

http://www.wsws.org/articles/2004/jan2004/poly-j07.shtml

http://www.cyberplace.org.nz/peace/nukenviro.html

 

[effisk]

There is no doubt that the nuclear tests have had an impact on the fauna and flora of the two atolls; I am however unsure they could have had an impact of the size of pearls harvested in Marutea Sud. Where did you read that oysters in Marutea Sud are bigger than in other places?

Marutea Sud is a few hundred kilometers to the East of Fangataufa and Moruroa.
The currents are from East to West in this part of the globe. And the major winds are either from the South or the East and North-East.
The Windward islands (including Tahiti), Leeward islands (to the West of the Windward Islands) and Samoa are all to the West of the Tuamotu.
The impact of released radioactivity is probably lower in Marutea Sud than in the Cook Islands.

I believe the beautiful pearls of Marutea Sud have more to do with the fact that it is the largest and one of the first pearl farms developed by Robert Wan, the largest producer of Tahitian pearls; they've had the time and budget to improve their techniques compared to smaller and more recent operations.

This being said, the French authorities have always said that the underground tests did not release much radioactivity in the air as the explosions vitrified the rocks, thus preventing the radioactivity to be released. I don't know if this is true or not, but what I know is that the ground under Moruroa is in bad condition and could collapse at any moment, creating a small tsunami and releasing more radioactivity.

 

[GemGeek]

We talked about this once, a long time ago, but you bring up some interesting points.

And Effisk, I hope Moruroa doesn't collapse. More things to worry about...

 

[Ramona]

Effisk:
I was thinking along the lines that radiation may have eliminated a parasite or spurred the growth of the oysters favorite food, since plant species generally have undergone a series of genome duplications during evolution and might be quite resistant to radiation. However, forget about it. I stumbled over a report dating from 1962 by the South Pacific Commission of Fisheries. This must have been the beginning of their interest in pearl culture. Marutea Sud was pointed out in the report for its specific arrangement of the lagoon and its big oysters. Based on this report, I would have gone straight there to culture my pearls.
Wan himself refers to oyster size being the reason for the big pearls he can culture. He also pointed out in an article I read that the lagoon is rich in plankton.

There were some tests done in 1987 and 1996 that showed that radiation was venting from the reef in large quantities. I could not find much reported in recent times. But it appears we saw the same reports that part of the atoll is subsiding and there are fears that it might collapse:

http://www.radioaustralia.net.au/pacbeat/stories/201103/s3164050.htm

GemGeek: You are right. I just saw the earlier discussions on this site about the same topic. Makes me feel less crazy. Thank you.

 

[effisk]

There were some tests done in 1987 and 1996 that showed that radiation was venting from the reef in large quantities. I could not find much reported in recent times. But it appears we saw the same reports that part of the atoll is subsiding and there are fears that it might collapse:

http://www.radioaustralia.net.au/pacbeat/stories/201103/s3164050.htm

The atoll made the news in France a couple of months ago. The tsunami and radiation issues were discussed. There is a tower in Moruroa where people can take refuge in case of a tsunami. There is a siren in Tureia to let them know a tsunami's coming, but no tower. The atoll is no more than 6 meters at its highest. Luckily the town of Fakamaru it at the northernmost tip of the island, opposite Moruroa, but studies estimate that even that part of the atoll could be partially submerged. (google maps)

 

[Josh]

Thyroid sickness rates in Polynesia are totally off the charts as are radiation related types of cancer. Anyone who has lived in Tahiti will tell you as much. I think that being a child on Ahe atoll where our farm (Kamoka) is is probably related to the hyperthyroidism I have had to contend with.
As for the testing making pearls bigger, who knows? The problem for humans I think was surely airborne. If you look at a map you can see that Moruroa is upwind of the trades that sweep Polynesia practically year round. Pretty incredible really.

I just went back in to the archives and found that old thread from 2007 about big pearls coming from Marutea and my own comment about how I didn't think radiation affected the oysters. Less than six months after that post I came down with hyperthyroidism. Also, since then I have had news of more people passing away in Tahiti from various types of cancers allegedly due to radiation exposure over 30 years ago (NOT implying that it is still an exposure issue today).

Apologies for the dark post. I'll be back to butterflies and rainbows shortly.