Monitoring of environmental working conditions is very important for many industrial sectors, especially, when poisonous or toxic organic solvents are used in production. In this work we present filled elastomer-nanostructured carbon based film as a promising material for nonselective gas indicator. The material is made by dispersing nanostructured carbon into the natural polyisoprene raw rubber matrix and vulcanizing afterwards. When the concentration of conductive filler is close to the percolation threshold such composite exhibits sharp changes of its electrical resistance when exposed to certain organic solvent vapor. The absorbed vapor causes the matrix to swell and increases the tunneling gaps between conductive filler particles, thus increasing the electrical resistance of the composite. Similar changes on electrical resistivity are observed due to mechanical interaction on composite, such as strain or external pressure. Thick film samples by thickness of 1 mm and 200 microns with embedded brass foil electrodes were made to compare their sensitivity to toluone vapor. All samples were weared-in by multi cyclic pre-straining using universal material testing machine. It was found out that decreasing the sample thickness leads to up to 5 times increased vapor sensitivity. This means although, that effective exposure time can be shortened up to 5 times for similar exposure conditions. The sensing intensity is compared and conclusions are made.