Luc Hornstra is a scientific researcher in microbiology in the Microbial Water Quality & Health team. He works on the optimisation of water treatment processes with the aim of rendering pathogenic microorganisms harmless. Over the last few years, Luc has conducted research on the treatment of water by, among others, soil aquifer treatment, (membrane) filtration and disinfection, such as UV and chlorine dioxide. For soil aquifer treatment, for instance, he determined the removal rates of viruses and bacteria during transport for both the saturated and unsaturated zones. In addition, Luc is working on a new method which uses viruses that are naturally present in water to determine the virus removal rates of treatment processes. Another of his important fields of research is antimicrobial resistance in the urban watercycle. For this research Luc is involved in the development of new techniques to detect and characterise antibiotics and resistance genes in the watercycle, and to establish the effect of water treatment processes on antimicrobial resistance. Within the European ANSWER project, Luc is supervising a doctoral student who is studying antimicrobial resistance in the environment. Luc is also involved in research into determining and influencing the microbial quality of water used in the horticultural sector.