Uncontrolled release of radioactive effluents into the public sewerage system

On 2nd August 2013, ASN was informed by the Haut-Lévêque hospital in Pessac that an abnormal level of radioactivity had been discovered in a wastewater drain pipe. Investigations showed that radioactive effluents from the vectorised internal radiotherapy rooms were being discharged directly into the public sewerage network instead of being routed to the radioactive decay tanks, between August 2012 and 27th July 2013, owing to a piping connection error. The connection had been defective since works were carried out in August 2012.

As soon as this contamination was discovered, the hospital suspended the treatments, until the piping had been correctly repaired. This was completed on 9th August 2013.

In response to an ASN request of 21st November 2013, the hospital stated on 13th February 2014 that the total activity released was estimated at 244 gigabecquerels (GBq) of iodine 131. According to the hospital, the doses received by the hospital staff working in the sector affected did not exceed 1 millisievert (mSv), which is the annual dose limit admissible for a member of the public.

ASN observes that this incident occurred, even though two other events concerning the storage of radioactive effluents had been notified to ASN by the same hospital in April and August 2012. These two events were examined by ASN, which conducted an inspection of the hospital’s nuclear medicine department in August 2012. It in particular raised the problem of the ageing of the radioactive effluent drainage pipes. ASN requested that all the radioactive effluent collection and decay systems be secured.

Location: Bordeaux university hospital
Event date: Fri, 02-08-2013
Nuclear event report
Legenda & explanation