has participant has_participant contamination Contamination The preferred term is biological contamination to distinguish from things like radiological contamination, contamination of the Gulf of Mexico with oil, the contamination of air with pollution, etc. The process of existence without reproduction of a pathogen of a particular biological taxon in or on some material entity or the process of reproduction of a pathogen in or on a material entity that is not an organism. The process of existence without reproduction of a pathogen of a particular biological taxon in or on some material entity or the process of reproduction of a pathogen in or on a material entity that is not an organism. William R. Hogan biological contamination pathogen reproduction material entity biological process biological_process organism