Spray waters 1–5 were collected from the research building and spray water 6 was collected from a location about 6 km from the university campus. However, the tap water supplying all of the toilets was from the same water source and the same water-purification plant. The band patterns in Figure 7 show two systems (band a, bands b and c) in almost the same location in spray waters 1–6; these are thought to represent bacteria from the shared water source. Note that band groups are evident below bands a1 to a6 in Figure 7, but these bands could not be confirmed or cut out. Sequence analysis was performed on the cutout bands shown in Figure 7, and the sequences that were obtained were identified by a Basic Local Alignment Search Tool (BLAST) search of the DNA Data Bank of Japan (Table 5).