Disclosed is a monitoring system for collecting and/or transdermally rediffusing air containing environmental contaminants. The inventive monitoring system generally includes at least one diffusion collector and/or an equilibrium diffuser. The diffusion collector is provided with at least three layers, i.e. an adhesive layer that is in direct contact with the skin of a living being, a barrier layer, and a collecting layer on the exterior face of the monitoring system. The equilibrium diffuser includes an adhesive layer and a collecting layer. The collecting layers and the adhesive layers of the two components of the monitoring system are preferably made of the same material and have the same dimensions.