2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/68132A contamination in a 3-manifold is an object interpolating between the contact structure and the lamination. Contaminations seem to provide a link between 3-dimensional contact geometry and the classical topology of 3-manifolds, as described in a separate paper. In this paper we deal with contaminations carried by branched surfaces, giving a sufficient condition for a branched surface to carry a pure contamination.19 pages 9 figuresGeometric TopologySymplectic Geometry57M50, 53D10text