Semantic Web for interoperable food safety legislation data: A case study Carlos Enrique Pintor 1 , Carlos Francisco Ragout 1 , Diego Torres 1,2 , and Alejandro Fernandez 1,3 1 LIFIA, Facultad de Inform´atica, UNLP, Calle 50 y 120, La Plata, Argentina. 2 Depto CyT, Universidad Nacional de Quilmes. Roque Saenz Pe˜ na 352, Bernal, Argentina. 3 Comisi´ on de Investigaciones Cient´ ıficas de la Provincia de Buenos Aires, La Plata, Argentina. Abstract. Food safety legislation plays a central role in regulating the levels of chemicals used in agriculture practices in order to prevent po- tential risks to consumers’ health within a certain region or country. Public Health organizations publish these regulations as recommenda- tions on allowed quantities of chemicals residues for different types of crops. These documents pose a major challenge for automatic processing as their format is not normalized nor the terminology used is uniform in any way. Semantic Web technology tools offer a solution as these docu- ments may be published as linked data which would allow computers to process them automatically, so that further analysis and interoperabil- ity would be possible. In this paper we introduce MRL-O, an ontology for describing data on allowed levels of residues present in commodities of agricultural origin. MRL-O serves as a standardized framework for sharing interoperable data and to provide tracking metadata about its sources and transformation processes. We also describe a step-by-step procedure to obtain MRL-O linked data from real non-normalized docu- ments. Also, we applied this procedure on data published by Argentina and Brazil with promising results. Consequently, we argue that the pro- posed ontology is sufficient to model the domain of MRL regulation and serves as the basis for tools that support interoperability in this domain. Keywords: Maximum Residue Limits, Agriculture, Health, Regulation, Semantic Web, Linked Open Data 1 Introduction Agrochemical substances and its derivatives are used throughout agricultural processes to prevent and control the presence of pests. As a result the products obtained from these practices may contain certain levels of chemical residues potentially harmful to human health. A mechanism to monitor and control the maximum concentration of pesticide residues (MRL) in food commodities is therefore required [7]. Governments and Health Organizations determine and 75 Short Papers of the 9th Conference on Cloud Computing Conference, Big Data & Emerging Topics