SILICOAT · Industrial implementation of processes to render RCS safer in manufacturing processes

In 1997, the International Agency for Research on Cancer (IARC) classified Respirable Crystalline Silica (RCS) in the form of quartz or crystobalite from occupational sources as carcinogenic for humans (category 1). Crystalline silica is an essential raw material for the production of virtually all the goods of everyday life. As a consequence, there can be significant amounts of RCS in the environments of many manufacture processes. Hence, a vast number of European workers are potentially exposed to RCS at their workplace. The ceramics industry is particularly concerned, since its products (heavy clay products, floor and wall tiles, sanitary ware, tableware, etc.) are based on silicates. The relevant bodies used in the manufacture of these products include considerable amounts of quartz, which is indispensable for the manufacturing process.The formal adoption of the IARC evaluation in Europe will strongly affect the way the products containing crystalline silica are produced, labelled, packed, marketed and disposed. These measures will clearly entail significant costs and influence the competitiveness of the companies, especially of the SMEs. However, there are evidences that the toxicity of the quartz can be practically nullified by certain substances. The mechanism by which these substances act seem to be related with the saturation of the silanol groups in the surface of the RCS particles, by “coating” them. Although some of the above treatments were known for years, they are not industrially used up to date. The main objective of the present project is the industrial implementation of these treatments in the ceramic manufacturing processes, thus transforming the quartz-containing raw materials into intrinsically safe products. The characteristics of the ceramic companies and their manufacturing processes made them especially suitable candidates. Furthermore, the experience gained in these industries will help in developing general-purpose treatments.