Detection of Radioactive Material from RDF Incineration Ashes at Chugai?s Fuji-Gotemba Research Laboratories

August 19, 2011 (Tokyo) - As a part of its contribution to the local community, Fuji-Gotemba Research Laboratories located in Gotemba City, Shizuoka Prefecture of Chugai Pharmaceutical Co., Ltd. [Head Office: Chuo-ku, Tokyo; President: Osamu Nagayama (hereafter, “Chugai”)] purchases RDF chips (solid fuel made from non-industrial wastes), from the local RDF center operated by Gotemba City, Oyama Kouiki Gyousei Kumiai (hereafter, “Kumiai”). These chips are incinerated by the Laboratory’s RDF dedicated steam boilers (hereafter, “RDF boilers”) to use the steam power as a source of energy consumed within the Laboratory. Chugai has been informed by the Kumiai that although the value is significantly lower than the reference value, radioactive cesium has been detected from the incinerated ash of RDF chips.
After radioactive cesium (cesium-134 and -137) was detected in high concentration in fly ash emitted from a non-industrial waste incineration plant in Tokyo in June this year, the Government of Japan required local governments in 15 prefectures, including Shizuoka Prefecture to measure the level of radioactive cesium in incinerated ash generated from non-industrial waste incineration plants.
To respond to the requirement, in July, the Kumiai made a voluntarily analysis of incinerated ash emitted from the RDF boilers of Chugai’s Fuji-Gotemba Research Laboratories, a major consumer of RDF chips. As a result, radioactive cesium was detected from the incinerated ash of RDF chips at a level far below the reference value set out for soils used for land disposal, which is 8,000 Bq/kg or below.
Currently, the RDF boilers are not in operation and Chugai is in discussion with the Kumiai regarding the future utilization of these boilers.
 ?Measurement Data?                                           ?Bq/Kg?





Total for Cs

Incinerated ash




Fly ash




?Specimen sampled on: July 8?



- RDF (Refuse Derived Fuel): a type of solid fuel made from household waste, crashed, dried and compacted after adding lime, etc.
- Fly ash means ash contained in emission gas collected by filters.
- Incinerated ash and fly ash with cesium concentration of 8,000 Bq/kg or below may be disposed by reclamation at the final disposal place. (Notice from the Ministry of Environment dated June 28, 2011 titled ‘Measurement and Temporary Handling of Incinerated Ash at Non-Industrial Waste Incineration Plants’)
- Indices on intake limitation of vegetables, crops, meat, eggs, fishes and other foods:
Cesium concentration of 500 Bq/kg or below (Pharmaceutical and Food Safety Bureau, MHLW dated March17, 2011)


Posted: August 2011

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