Samut Prakan nuclear accident
The Samut Prakan nuclear accident happened in Thailand in February 2000 . The release of ionizing radiation from a disused medical cobalt 60 radiation device killed at least three people and more than a thousand were exposed to increased radiation exposure. The area of a scrap yard in Samut Prakan (about 20 kilometers as the crow flies from Bangkok city center) was mainly affected .
Accident and its discovery
The event was triggered by several radiation sources that came from radiation therapy devices and had been illegally stored by a company in an unprotected parking lot in Bangkok since October 1999. The actual accident occurred when scrap collectors took one of these sources into their possession, took it to a junkyard and there broke open the protective covering so that the materials ( lead , steel ) could be sold separately.
The written warning attached to the housing of the radiation source - which, however, was not written in Thai - as well as the presence of the radiation warning sign on the casing was not heeded by the scrap collector, the junkyard worker or the junkyard owner, possibly the people Meaning not known either.
In the days that followed, all those involved developed the typical symptoms of high radiation exposure : malaise, loss of appetite, diarrhea, sunburn-like skin damage, and finally large, open wounds and hair loss. Despite these complaints, the scrap collectors only sought medical help in a nearby hospital more than a week after the radiation source was opened. The doctors working there again only correctly interpreted the present clinical pictures as radiation sickness after a few days , after the employees of the junkyard also came to the hospital with similar symptoms. A total of ten people from the vicinity of the scrap collectors were exposed to particularly strong radiation from the opened cobalt 60 source.
In the meantime, 17 days had passed since the spring was uncovered and it had been showered with scrap in the poorly organized heap of material in the junkyard. After the competent authority was informed of the presumption that there must be an unprotected radiation source in the living environment of the patient, the search for the source and preparations for recovery began immediately.
Salvage
Measurements carried out at the scrap yard showed very high radiation values: At the entrance to the scrap yard, about seven meters from the source, the value was 50 mSv / h . Directly at the scrap heap with the open source, the measurements showed up to 10 Sv / h. (For comparison: liquidators who were used to clean up the reactor roof during the Chernobyl disaster received a dose of about 200 mSv, which corresponds to 12 Sv / h, within about a minute. It was right next to the open source in the junkyard thus the radiation - but limited to a relatively small area - at a level comparable to that in Chernobyl.)
An evacuation was initially considered by the responsible authorities, but then discarded in order not to cause panic. Only a shut-off for the dose range above 0.3 mSv / h was made, which corresponded to a radius of about ten meters around the junkyard.
Rapid recovery and securing of the cobalt-60 source was made more difficult by the fact that on the one hand the exact location of the source was not known and the work was still hampered by large quantities of other scrap that was stored unsorted on the area. In addition, the emergency services involved were poorly equipped with regard to rescue technology and protective equipment. That is why unconventional means were used: For example, a fluorescent plate was used to localize the radiation source in the junkyard , which was mounted on the tip of a long bamboo stick. During work at night, the position of the source could be successfully determined, as the plate near the radiation source was made to glow. To do this, however, one had to wait until there was no more annoying moonlight. The source could finally be separated from the remaining scrap and secured in a lead container.
A total of 52 people were deployed in the rescue work. The highest radiation exposure received for people from this group was 32 mSv.
Consequences and effects of the accident
The people living in the vicinity of the junkyard were exposed to radiation levels within a period of about three weeks that exceeded the radiation naturally occurring in the environment many times over. At the time of the accident, 1,872 people were living within 100 meters of the junkyard. A group of 258 people lived within 50 meters of the junkyard, including five pregnant women. One of these women decided to have an abortion because of the accident .
The radiation exposure of the ten directly involved (scrap collector and dealer, junkyard worker and relatives of these people) was enormous: subsequent calculations resulted in four whole-body doses of around 2 Gy , for two other individuals the values were between 2 Gy and 6 Gy and the the remaining four people suffered loads of more than 6 Gy. The equivalent dose for the different cohorts of people was thus - since it was a matter of gamma ray exposure - around 2 Sv , 2 Sv to 6 Sv and more than 6 Sv. Of the last four involved, two 18 and 20 year old male employees of the junkyard owner, as well as her husband, died within eight weeks.
After several years of litigation, a Thai court sentenced the company responsible for the illegal storage of radiation sources ( Kamol Sukosol Electric Co Ltd ) to pay compensation totaling 640,276 baht . Divided into the twelve radiation victims suing in this process, this results in a total compensation of around 1,300 euros each .
Consequences on an international level
This and similar accidents led the IAEA to develop the new additional warning symbol for dangerous radioactive substances , which was specially designed so that even uneducated groups of people (e.g. children, illiterate people ) can correctly interpret the symbols.
See also
Web links and sources
- Detailed report of the IAEA (English; PDF file; 1.06 MB)
Individual evidence
- ↑ Bangkok Post: Radiation victims lose compensation , October 21, 2009