Radioactive strontium found in Yokohama, 250 km from Fukushima plant

YOKOHAMA (Kyodo) — Radioactive strontium exceeding normal quantities has been detected in sediment from atop an apartment building in Yokohama, some 250 kilometers from the damaged Fukushima Daiichi nuclear power plant, city officials said Wednesday.

While the discovery of 195 becquerels of strontium 90 in the rooftop sediment has fueled concerns that leaked radiation may have spread further than the government had expected, the officials said the city office is carefully examining where the material came from.

This is the first time strontium at a concentration of over 100 becquerels per kilogram has been found beyond 100 km from the Fukushima plant. The strontium 90 was detected in Yokohama, south of Tokyo, by a private agency that conducted the test upon the request of a resident.

Strontium 90, with a half-life of 29 years, has been detected at concentrations roughly between 10 to 20 becquerels at various places across Japan prior to the nuclear crisis triggered by the March 11 earthquake and tsunami.

After learning about the findings, the Yokohama city is now investigating soil samples collected from areas near the building, the officials said. Meanwhile, the science ministry said it is still uncertain whether the strontium had come from the Fukushima nuclear accident.

“Radioactive substances tend to accumulate in sediments and so we still don’t know whether the substance found in this test had come from the nuclear accident,” an official of the Ministry of Education, Culture, Sports, Science and Technology said.

The ministry has detected radioactive strontium at various locations in Fukushima and Miyagi prefectures within 100 km from the crippled plant in earlier investigations following the accident.

If inhaled or ingested, strontium tends to accumulate in bones just like calcium. It is believed to cause bone cancer and leukemia.

Kyodo Press, October 12, 2011
http://mdn.mainichi.jp/mdnnews/national/archive/news/2011/10/12/20111012p2g00m0dm111000c.html

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Radiation Dose Limit for Fukushima Plant Workers to Be Lowered

Tokyo, Oct. 14 (Jiji Press)—The Japanese health ministry will lower its accumulative radiation dose limit for workers at the crippled Fukushima No. 1 nuclear power station in early November, officials said Friday.

The limit was lifted to 250 millisieverts after the nuclear accident caused by the March 11 disaster, but it will be brought back to 100 millisieverts.

The current exceptional limit will continue to be applied to existing workers there as well as newcomers engaging in emergency operations, such as the repair of reactor-cooling and water-decontaminating facilities if they break down.

Such emergency operations will unlikely be needed, a health ministry official said.

Jiji Press, October 14, 2011
http://jen.jiji.com/jc/eng?g=eco&k=2011101401012

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Fukushima Pref. starts thyroid exams for children

FUKUSHIMA (Kyodo) — The prefectural government of Fukushima on Sunday started ultrasonic thyroid examinations for children aged up to 18 when the nuclear crisis at the Fukushima Daiichi power plant began in March.

In a move almost without precedent in the world, around 360,000 children in the prefecture will be examined at the Fukushima Medical University.

Parents in Fukushima have shown concern over the issue as many children suffered thyroid cancer after the 1986 Chernobyl disaster.

The local government plans to at first examine 4,908 children living close to the nuclear power plant, and then to complete the whole process by March 2014, officials said.

The children will go through follow-up exams every two years until they turn 20. After that, the checkups will be conducted every five years over the person’s lifetime.

Detailed exams will be conducted if any pathological lesions are detected.

Kydo Press, October 9, 2011
http://mdn.mainichi.jp/mdnnews/national/archive/news/2011/10/09/20111009p2g00m0dm016000c.html

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New safety rules for workers near N-plant

The health ministry will lay down a set of rules aimed at protecting the health of personnel working to decontaminate areas around the Fukushima No. 1 nuclear power plant, ministry officials said Friday.

The rules will require such workers to have their radiation levels tested and oblige them to wear protective masks.

The new regulations, to be incorporated into the Industrial Safety and Health Law, are designed to protect the health of workers engaged in such tasks as open-air decontamination and the disposal of radioactive waste in the vicinity of Tokyo Electric Power Co.’s crippled facility, according to the Health, Labor and Welfare Ministry.

The current rules only cover personnel working inside nuclear power facilities. Starting in January, however, full-fledged efforts will be made to decontaminate radiation-polluted areas and dispose of radiation-contaminated sludge and debris. The ministry will soon start working out the details of the new rules, with a view to enforcing them in January, the officials said.

It is envisaged that they will be applied in areas near the nuclear plant where annual accumulated levels of exposure to radiation from outside the body are 5 millisieverts or higher.

Under the new rules, workers will be obliged to wear dosimeters and masks, and employers will be legally bound to educate workers about how to minimize exposure from outside the body.

Yomiuri Shimbun , October 8, 2011
http://www.yomiuri.co.jp/dy/national/T111007004633.htm

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