Pollution of air and water are major concerns both at domestic and European Union level. With the aim in view to preserve and improve water quality, the European Community has adopted a water framework directive (WFD). Its objective is to achieve a good ecological and chemical status of waters by 2015. In this context, research in metrology has been engaged at INERIS in order to detect pollutants such as heavy metals {both in ionic or particulate forms}. Though they were not cited in the directive since they are considered as emerging pollutants, nanoparticles are an object of concern whose detection should be made possible as well. The constraints imposed by regulations and the emergence of new pollutants, emphasize the need to develop an instrument allowing in-situ and real-time elemental identification and mass concentration determination of particles suspended in water. Environmental monitoring and surveillance of pollutants in particulate form possibly released in waste waters by industries involved in nanoparticle manufacturing and processing are two telling examples of applications of such instrumental development. The LIBS (Laser-Induced Breakdown Spectroscopy) technique was retained to tackle such issue.