[Microbial colonization of moistered bitumen and high-grade steel plaids revealed by scanning electron micrographs].

There have been some reports about the increase of colonic counts and microbial growth on the surface of materials in the sphere of tap water. But there have been no hints about the development of the initial colonization with microorganisms from the water to a growth on the surface. The development of a microbial community on high-grade steel or solvent containing bitumen was revealed in a comparative study by scanning electron microscopy. There was hardly any increase in the count of bacteria on high-grade steel during the four weeks exposition. On bitumen there was a dense and multilayered growth with bacteria. Already within one week the number of bacteria on bitumen was much higher than on high-grade steel.