Background Chemical seed dressing pesticides are currently used to protect the crop yield and quality from seed-borne diseases. It has been estimated that in 2001, Sweden alone accounted for 68.9 tons of chemical seed dressing pesticides used for cereal cropping, while in Europe as a whole the quantity is approximately 2000 tons annually. The use of these chemicals causes environmental problems, some of which have an impact on human health. More specifically, the problems affect people employed in the seed industry and in farming, birds are contaminated when picking up seeds in the fields, soil and groundwater is also contaminated and there is a need to treat leftover seeds as chemical waste. The EU has expressed concern, in the 6th Environment Action Plan, about the use of pesticides, and has drawn up a thematic strategy on the sustainable use of pesticides. There is thus a strong and clearly identified need for a new method of sanitizing seeds from diseases which also ensures the production of cereal seed free from undesired additives and which is environmentally sustainable. Objectives The objective of the project was to develop and demonstrate a full-scale thermal treatment of cereal seeds, thus reducing the use of chemicals in agriculture. This was to be achieved essentially by processing cereal seeds in humid air in carefully controlled conditions to control the pathogens. The new method was to be based on previous research and development work carried out at the laboratory scale. The project was to construct a prototype treatment plant. It would consist of treatment and cooling devices, sensing system, system control software, power supply and seed transportation equipment. The project would then test the results of the treatment method; develop a thorough quality control system as well as maintenance procedures and services. Finally, certification of the method was to be obtained in compliance with the Council Directive 66/402/EEC. Furthermore, the project aimed to construct a full-scale seed treatment plant with a capacity exceeding 200 tons per day. One treatment plant was expected to reduce the use of chemical seed treatment chemicals by some 2.5 tons of the active ingredients per year, which is close to 4% of the use of these chemicals in Sweden. The certification and demonstration was expected to lead to an extensive spread of the method in the EU. Immediate benefits would be an end to the exposure of farmers to the chemicals and the leftover treated seed would no longer be problematic waste. Results The ThermoSeed treatment process developed is a combination of steam and heat applied to seeds without any chemicals, presenting a clean and effective production method. Initially, in the project, an intermediate system was developed and installed, which was run under commercial conditions. The equipment assembled a large variety of components from several manufacturers. The treatment parameters were tested as well as the mechanical characteristics of the process. After evaluation by sampling, testing, and quality control, the full-scale processing system was developed, having a treatment capacity exceeding 200 tons per day. The treatment process is very effective and has a low energy consumption.. The ThermoSeed concept has been approved by the Swedish Seed Testing and Certification Institute (now a part of the Swedish Board of Agriculture) as an equivalently effective alternative to chemical seed treatment, The full-scale treatment system was installed in Skara, Sweden and has been operational since September 2005. The project partners are actively promoting further applications of the system. This project has been selected as one of the 21 "Best" LIFE Environment projects in 2005-2006