研究是用从饮用水分配系统中获得的颗粒物进行的。添加营养素后，本地附着的细菌群和添加的大肠菌群与颗粒一起累积。和这些颗粒有关的生物体数量的急剧增加并没有反映在含有水的颗粒的平板计数中。这些结果表明，在细菌突然释放到水中之前，通过对大量水进行采样无法检测到的生物体，表面可能起到了窝藏生物体的作用。包括30个参考文献，图表。

Studies were conducted with particles obtained from a drinking water distribution system. Upon nutrient addition, both the indigenous attached population of bacteria and added coliforms accumulated in association with the particles. This dramatic increase in numbers of organisms associated with the particles was not reflected in plate counts of the particle-containing water. These results indicate the potential role of surfaces in harboring organisms that are not detected by sampling the bulk water--until the bacteria are suddenly released into the water. Includes 30 references, figures.