Concentration of cadmium in tobacco cigarette brands traded in Guayaquil, Ecuador. Revista Científica Ciencias Naturales y Ambientales, [S. l.], v. 14, n. 1, 2020. DOI: 10.53591/cna.v14i1.1286. Disponível em: https://revistas.ug.edu.ec/index.php/cna/article/view/1543. Acesso em: 5 dec. 2025.