title: In vitro study of possible microbial indicators for drowning: Salinity and types of bacterioplankton proliferating in blood.
abstract: Numbers and types of bacterioplankton proliferating in blood samples mixed with water of various salinity levels were examined to determine the characteristics of species associated with salinity. Water samples (total n=88) were collected from the midstream of two rivers (freshwater; n=10; salinity <0.05%), from around their estuaries (areas of freshwater, n=20, salinity <0.05%; areas of brackish water, n=20, salinity <0.05-3.1%; areas of marine water beyond the mouths of the rivers, n=28, salinity 2.4-3.3%), and from the coast (areas of marine water; n=10; salinity 3.3-3.5%). Freshwater bacteria were identified in 41 of 42 blood samples mixed with water at ≤1.3% salinity, and the genus Aeromonas, which is universally distributed in freshwater environments, was predominant. Marine bacteria were identified in all of 46 blood samples mixed with water at ≥1.8% salinity, and most comprised the genera Vibrio and Photobacterium that are universally distributed in seawater environments. Aeromonas was undetectable in all blood samples mixed with brackish or sea water at ≥1.8% salinity although they are detectable even in seawater environments. Thus, the present results showed that bacterioplankton capable of proliferating in human blood reflects the salinity of water.
authors.affiliation: Section of Legal Medicine, Department of Social Medicine, Faculty of Medicine (Miyazaki Medical College), University of Miyazaki, 5200 Kihara, Kiyotake-cho, Miyazaki 889-1692, Japan. eijik@med.miyazaki-u.ac.jp
authors.forename: Eiji
authors.initials: E
authors.lastname: Kakizaki
authors.forename: Shuji
authors.initials: S
authors.lastname: Kozawa
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Matsuda
authors.forename: Eri
authors.initials: E
authors.lastname: Muraoka
authors.forename: Taketo
authors.initials: T
authors.lastname: Uchiyama
authors.forename: Masahiro
authors.initials: M
authors.lastname: Sakai
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Yukawa
mesh_terms: D000818:Animals; D001769:Blood / Q000382:microbiology*; D004332:Drowning / Q000175:diagnosis*; D005554:Forensic Medicine; D005618:Fresh Water; D006092:Gram-Negative Facultatively Anaerobic Rods / Q000235:genetics / Q000254:growth & development*; D066298:In Vitro Techniques; D049449:Luminescence; D010933:Plankton; D012336:RNA, Ribosomal, 16S / Q000378:metabolism; D054712:Salinity; D012623:Seawater; D017423:Sequence Analysis, RNA; D013194:Staining and Labeling; D014871:Water Microbiology
chemical_list: D012336:RNA, Ribosomal, 16S