Simpler radioactive wastewater processing

The BioChroma process provides what is reportedly not only a more flexible means than traditional “delay and decay” systems of dealing with this “by-product” of medical treatment, but also one that requires less plant space, affords less risk of leakage or cross-contamination, and is easier to install.

While undergoing nuclear medicine therapy using 131I radioisotope in hospital, patients generate wastewater containing a considerable amount of radioactivity. Thus, contamination can reach levels of as high as 90% of the radioactive dose administered to the patient, depending on the type of therapy the patient underwent.1,2 Given its radioactive half-life of 8.02070 days, there is a significant risk of 131I radioisotope accumulation after its discharge into the sewer network (through sanitary wastewater) and into the environment. Therefore, it is advisable to collect this effluent in a separate system for treatment prior to final discharge to the municipal sewer.3–8 In spite of the clear scientific evidence of the severe contamination of this specific type of wastewater, a harmonised legal framework has still not been devised for all member states of the European Union. A survey conducted by the Radiological Protection Institute of Ireland clearly spotlights the discrepancies existing among methods for managing radioactively contaminated effluents. The survey examined 13 countries, six of which stipulate the installation of wastewater treatment systems (Table 1); three of which permit the wastewater to be discharged directly following dilution (Table 2), and four of which permit both options (Table 3), depending on the specific conditions of the respective sanitary system.9 Delay and decay (natural decomposition of the isotope) is the most commonly used technical method of abating 131I, but it is frequently criticised as being complex and very expensive.9–12 While searching for alternatives to this proven, but somewhat old-fashioned, technology, an alternative method called BioChroma was developed. This paper describes the technology and presents, as an example, a system that was installed and commissioned in mid-2008 in a nuclear medicine therapy facility with 12 beds in Stuttgart (Germany).

Patented, biological system