Background Prolonged inhalation of crystalline silica particles can cause lung inflammation and the lung disease known as silicosis. Total European usage of crystalline silica (i.e. quartz and crystobalite) is measured in thousands of millions of tonnes per annum. It is used in many manufacturing industries such as the cement, ceramics, steel, glass, mineral wool, aggregates, mortar and concrete sectors. Hence, a vast number of European workers, around four million (European Trade Union Confederation, 2007), are potentially exposed to Respirable Crystalline Silica (RCS) in the workplace. Although it is not possible to substitute crystalline silica in many of the sectors where it is used, it is possible to nullify its toxicity by treating it with certain substances. Objectives The main objective of the SILIFE project is to produce commercial quartz powders that have very little or zero RCS toxicity. This new coating technology would be replicable in any industry that uses separate dry quartz powders as raw materials. Specifically, the project aims to: Design a pilot plant for the treatment of commercial quartz powders that has the capacity to treat 500 000 kg of quartz per year (considering 8 000 working hours/year); and Demonstrate that the treated powders exhibit much less toxicity than the untreated quartz. (The treated quartzes will be demonstrated in the manufacturing processes of five quartz end-users belonging to other sectors than ceramics.)Expected results: 75% reduction RCS toxicity of quartz treated in the pilot plant in comparison with untreated quartz; Identification of at least two treatments for the above reduction in quartz toxicity, whose associated treatment costs amount to less than €0.025/kg; and Production of around 10 000 kg of treated quartzes for the end-users to test in their manufacturing processes.