Functional group analysis of cigarette butts in beach sand and their association with microplastics: Bocagrande Beach, Cartagena, Colombia - Claudia Díaz-Mendoza; Javier Mouthon-Bello; Camilo M. Botero; Juan Valdelamar Villegas; Leonardo Gutiérrez; Keydis Martinez-Villadiego (PLoS ONE, 2026)