A number of our diagnostic and life science research products function by using small amounts of radioactivity that can be detected in trace amounts, providing unique information to clinicians and researchers. Radioactivity is also used in our therapeutic products to treat diseases such as prostate cancer and relieve pain in bone metastases. This is closely regulated in the countries in which we operate. The regulatory controls cover transport, packaging, handling, storage and use of radioisotopes and the management of residues from the production process.

We also provide advice and training to our customers on safe handling of radioactive materials. At our sites in Kjeller, Norway and Amersham, UK we also recycle radioactive generators returned from our customers.

Emissions to air and wastewater discharges
Manufacturing of radioactive material does involve the controlled release of radioactivity to the environment. The radioisotopes we use have half-lives ranging from several hours or less to thousands of years. The half-life is the time for the amount of radioactivity to fall by 50%. Most of our radioactive releases have short half-lives, reaching background radiation levels within a few months. Background radiation is present in all parts of the environment and is composed of radioactivity from naturally occuring sources such as cosmic rays, rocks, soil and foodstuffs. An additional small amount of background radiation derives from man-made sources. In the UK, the average background radiation level is around 2,600µSv (See Performance - Health and safety: Radioactivity).

All of our emissions and discharges are governed by permits from regulatory authorities and in 2000 and 2001 we complied with these in full. In cooperation with regulators, we are pursuing programmes to reduce radioactive discharges.

In 2001 Arlington Heights in the US completed the construction of a new treatment plant for wastewater containing radioactivity. This has led to a 95% reduction in the total radioactivity discharged to sewer and a 91% reduction in the average concentration of radioactivity in wastewater in 2001.

Disposal and decommissioning
In 2000 and 2001, most of the solid radioactive waste that we generated was classified as very low level or low level radioactive waste. This waste was disposed of at third-party sites licensed by national governments.

Any intermediate level radioactive waste is stored in purpose built facilities on our sites, until government approved repositories become available. These facilities are built for waste generated only on our sites and are designed to hold radioactive materials safely and securely. We also store some materials with a relatively short half-life in our facilities to enable them to decay to a level that enables disposal off-site.

In the UK, we started a major programme in the late 1990s to safely store or dispose of approximately 800 cubic metres of mixed radioactive waste that had been originally destined for disposal at sea. The option of sea disposal was withdrawn after the UK Government adopted international treaties to ban this. We have sorted through the contents of the majority of the concrete lined sea drums containing the waste and repackaged it for either storage at our facilities or disposal at third-party sites. So far, this has resulted in an 8:1 reduction in the volume of waste stored. To continue this work, a purpose built plant has been constructed at our decommissioning facility at Harwell, which was approved by the Nuclear Installations Inspectorate in early 2002.

The amount of waste disposed off-site is dependent on the proportion that we store on-site and also our decommissioning and refurbishment activities. We aim to decommission redundant plant and equipment as soon as practicable (See Graph 10).

Principal sites manufacturing radioactive materials
Site location	Isotopes used in products
Germany Braunschweig	I-131 Tl-201	Cancer therapy Medical diagnosis
UK Amersham	I-125, Sr-89 P-32, P-33, S-35 TL-201, Ga-67, In-111, Mo-99/Tc-99m	Cancer therapy Life science research Medical diagnosis
Cardiff	H-3, C-14	Life science research
US Arlington Heights	I-125 TL-201, I-123, In-111	Cancer therapy Medical diagnosis
South Plainfield	TL-201, Sr-82/Rb-82	Medical diagnosis
Japan Chiba	F-18, GA-67, I-123, Xe-133, Mo-99/Tc-99m, Rb-81/Kr-81m	Medical diagnosis
Hyogo	F-18, I-123, I-125, In-111, MO-99/Tc-99m, Rb-81/Kr-81m, TL-201	Medical diagnosis
Netherlands Eindhoven	I-123, Rb-81/Kr-81m	Medical diagnosis
Norway Kjeller	I-131 MO-99/Tc-99m	Cancer therapy Medical diagnosis
Italy Saluggia	I-131 I-123, I-125, GA-67, TL-201, MO 99/Tc-99m	Cancer therapy Medical diagnosis