During her 1 month stay, Dr Perrine Mangion performed the extraction and isotopic analyses of N and O in nitrates from groundwater and river water samples from La Réunion to identify the origin of the nitrate contamination. She worked in collaboration with Natacha Brion, Florian Deman and David Vertraeten. Perrine plans to develop the use of isotopic tools in environmental studies in La Réunion, and for that purpose a new collaboration will be established with AMGC.