Radiological monitoring of the French environment is one of IRSN's permanent tasks as part of public policy on nuclear safety and radiological protection. It helps to guarantee the best possible protection for the population.
Carried out in Polynesia since 1962, this monitoring focuses on seven islands (Tahiti, Maupiti, Hao, Rangiroa, Hiva Oa, Mangareva and Tubuai) which are representative of the five archipelagoes. It consists in taking monthly samples of various kinds from the different environmental compartments (air, water, soil, food, etc.) with which the population may be in contact.
Regarding food, the samples analyzed are representative of the diet of Polynesians living in the five archipelagoes of the region and are taken from the marine environment of the open sea, the lagoon environment and the terrestrial environment.
Almost all samples are measured at the IRSN Laboratory for the Study and Monitoring of the Environment, based in Vairao on the island of Tahiti, plus a few samples at the IRSN Orsay Laboratory. The year 2011 was marked by the Fukushima nuclear accident, which occurred on March 11. Within this context, IRSN stepped up its monitoring activities in French Polynesia and was able to confirm the absence of radiological impact in New Caledonia and Polynesia. This report does not include all the data and results relating to the accident, but provides a summary for the year 2011.
As in recent years, levels of radioactivity, which fell steadily as of 1974 when French atmospheric nuclear weapons testing came to an end, were stable and very low in 2011. The residual radioactivity is mainly due to cesium 137. In terms of additional dose, this artificial and residual radioactivity is lower than 5 microsieverts per year. This corresponds to less than 0.5% of exposure due to natural radioactivity in Polynesia (approximately 1000 microsieverts per year).
More information :
Download the report IRSN PRP-ENV/SESURE/2013-08 « 2011 report on radioactivity monitoring in French Polynesia »