# Sustainability in Italian Ceramic Tile Production: Evaluation of the Environmental Impact
## 1 Introduction  
Sustainability has recently become a very popular topic and is currently relevant, strongly changing the environmental, economic, and social vision of the world. The concept of sustainability emerged during the late 1980s as a consequence of important debates at global level; it was defined as the development of the existing society which would be able to preserve the needs of future generations [1]. In this context, the whole industrial manufacture, energy production and consumption had to comply with rigorous legislations, so as to reduce their impact on the environment and consequently on the society, providing, thus, a more sustainable economic development. Construction materials is one of the biggest industrial sectors, and in recent years a lot of actions have been implemented to improve the sustainability in this field. Over the last two decades, strong innovations have been introduced in the construction materials production and in the assessment of the environmental impact of new constructions and architectures [2]. Global issues, such as urban heat island effect, city overpopulation and uncontrolled level of greenhouse gas emissions, have pushed the building sector to find alternative and innovative solutions [3; 4; 5; 6]. Together with concrete, steel, glass and wood, ceramic is one of the most used building materials. Ceramics are inorganic and non-metallic materials mostly employed in buildings as wall, floor, and roof tiles or in mosaics. In addition, due to the low production costs, high physical and chemical properties, biocompatibility and their peculiar aesthetical features, ceramic materials are also used to produce tableware, sanitaryware, artistic sculptures, etc. However, in the building sector, ceramic tiles are industrial products characterized by the largest production and relevant economical value. Focusing on ceramic tiles, amongst the world competitors, the Italian industry is deeply involved in the environmental impact assessment and its efforts constantly aim at the improvement of the sustainability of the production processes [7; 8]. In addition, the ceramic tile industry is of great importance for the Italian economy and society; the economic impact of this sector consisted of revenue of almost 5 billion euro in 2018 [9]. In the same year, Italy was rated as the sixth world ceramic tile producer, as the second in Europe, with 416 million square meters of manufactured tiles (79% of that assigned to export) [10]. The two biggest European ceramic clusters are located in Spain and Italy, respectively in the Castellon (Valencia) and Sassuolo (Modena) districts. Due to the extremely high concentration of productive plants in those regions, the quality of air has been constantly monitored and a strong awareness toward the environmental impact of the production processes has surely increased in recent years. A wide number of scientific studies and analytical surveys have been carried out in order to evaluate the air quality and study the meteorological events affecting the pollution levels in those areas [11; 12; 13]. The Sassuolo district expands over the Modena and Reggio-Emilia provinces and supplies over 80% of the whole Italian ceramic tiles production. In 1978, the influence of pollutant emissions was correlated to the pollutant concentration profiles recorded at ground level, thanks to extensive research on the climatic condition of the territory [14]. These studies allowed the quantification of the pollutant emission limits for an optimized compliance to the environmental quality standards of that period. Since then, air quality of the Italian district has been constantly monitored [7; 15; 16; 17]. In particular, the control of the emission flows and the improvement of the existing limits have been carried out through the updating of the Ceramic BRef (Best Available Techniques Reference Document) [18].