After a diploma in industrial chemistry in 1964 at the E. Molinari Technical High School in Milano, he wins a fellowship at the Mario Negri Institute for Pharmacological Research were he works through 1973 at the Laboratory of Biochemical Pharmacology in the field of drug metabolism and analytical chemistry. In 1974 after obtaining a degree in Biological Sciences at the University of Milano he joins the Institute of Lipid Research, Baylor College of Medicine in Houston USA as Visiting Assistant Professor in Biochemistry were he works on the development of mass spectrometry based methodologies for the detection of toxic compounds. In 1975 he joins as permanent staff member the Laboratory of Mass Spectromety at the Mario Negri Institute in Milano were he develops new quantitative techniques for the trace analysis of xenobiotics. In 1976 he is involved as coordinator of a group of research in the risk assessment activities following the dioxin accident at Seveso; two years later he leads the new Laboratory of Environmental Pharmacology and Toxicology at the Mario Negri Institute in Milano with research interests devoted to the study the presence of xenobiotics in the environment and their effects on biological systems. During the following 10 years the laboratory grows to a staff of more than 30 research personnel with research activities ranging from the development of sophisticated analytical techniques to identify and monitor the presence of pollutants of emerging concern, such as persistent halogenated compounds, to the use of molecular tools to identify biomarkers of exposure and effect in the general population and their application in epidemiology studies and risk assessment. In 1997 Dr. Fanelli is nominated Head of the Department of Environmental Health Science at the Mario Negri Institute were he is coordinating the research activities of 4 laboratories and 2 units ( Analytical Biochemistry, Environmental Chemistry and Toxicology, Mass Spectrometry, Food Toxicology, ) working on different aspects of the effect of environmental toxic compound on animal and human health. Dr. Fanelli has been a coordinator of national(National Research Council) and international (NATO) research projects and was a partner of projects of the 5th and 6th Framework programs (EU). He has been Temporary Advisor of the World Health Organization for the problem of dioxin incinerator emissions. Dr. Fanelli is author of more than 300 scientific papers published in peer reviewed international journals and organizer of international symposiums in the field of environmental risk. He is a Member of the National Consulting Board for Plant Products Authorization Dr. Fanelli has also been appointed in the past to the “Scientific panel of environmental pollutants in the food chain “ at the European Food Safety Authority (EFSA). He is an Eurotox Registered Toxicologist.