Objective: To analyze the self-reported knowledge and behavior on the disposal of medicines. Method: A cross-sectional study with data collected through a questionnaire in May 2017, in the city of Picos-PI, with a sample of 153 residences. Results: Regarding the selfreported knowledge, 139 (90.8%) stated that they had knowledge about environmental risk, 144 (94.1%) reported having no knowledge of the appropriat...