title: Determinations of microbial loads associated with microscopic-size particles of Kennedy Space Center soil.
abstract: Plate counts for six fractions, of micrometer-size, of Kennedy Space Center soil provided estimates of aerobic, mesophilic, heterotrophic, microbial loads on single soil particles. Analyses included unheated particles, particles subjected to wet heat at 80 degrees C for 20 min, and particles subjected to dry heat at 110 degrees C for 1 hr. Unheated particles yielded mean counts ranging from 6 colonies per particle for the smallest (44-53 micrometers) soil fraction to approximately 55 colonies per particle for the largest size (105-125 micrometers) soil fraction tested. Mean counts for heat-resistant forms ranged from 2 colonies per particle for the smaller particles to 12-15 colonies for the largest particles analyzed.
authors.affiliation: School of Public Health and Department of Food Science and Nutrition, University of Minnesota, Minneapolis, USA.
authors.forename: O R
authors.initials: OR
authors.lastname: Ruschmeyer
authors.forename: I J
authors.initials: IJ
authors.lastname: Pflug
mesh_terms: D001419:Bacteria / Q000302:isolation & purification*; D015169:Colony Count, Microbial; D003264:Containment of Biohazards; D005118:Extraterrestrial Environment; D005431:Florida; D006358:Hot Temperature; D010316:Particle Size; D012988:Soil Microbiology; D013026:Space Flight