Characteristics of the components of suspended particulate mater (SPM) were investigated, as well as their seasonal variations and compositions in the mountainous and urban areas. The mountainous sampling site was Happo Ridge at an altitude of 1850m and the urban site was the city area in Nagano, the both being in the central mountainous region in inland area of Japan. SPM was sampled by filtering air on a quartz fiber filter set in a low volume air sampler, with a flow rate of 20 1 min E-1 and for a period of one month. In the mountainous area, SO42- concentrations were much higher in spring and summer than those in fall and winter. Almost all of SO42- were considered to be produced by the photooxidation of SO2 and transported for a long distance into that area. Ca2+ concentration increased particularly in March and April in which yellow sand from the Asia Continent arrived at those sites. The seasonal variation of elemental carbon (EC) concentration was small, while organic carbon (OC) increased in spring and summer. This suggested that OC in spring and summer was produced by photochemical reaction. In the urban area, SO42- concentration increased in spring and summer. This seasonal variation was similar to that in the mountainous area, but that level was smaller. Ca2+ concentration increased in winter as a result of the road dust raised by cars. SO42- was most abundant in the mountainous area and attained more than 10 % of the SPM. EC, OC and SO42- were abundant in the urban area and all these components, respectively, were more than 10 % of the SPM. The total concentrations of chemical components analyzed attained 43 % and 68% of SPM in the mountainous and urban areas, respectively. Secondary components occupied 41% and 34% of the total components in the mountainous and urban areas, respectively. The contribution of secondary components in the mountainous area is larger than that in the urban area.

A survey of the incidence of Salmonella in samples collected from three treatment plants of sewage, food-poisoning, sporadic case with acute enteritis and healthy carrier in a local city, was performed from Aprile 1974 to December 1978. Salmonella were very frequently found in Influent sewage. The range of sewage source serovars found was wide and most aerovara were related with human source. A total of 954 strains and 62 serovars of Salmonella were found in sewage and human source. S. typhimurium, S.tennessee, S.thompson, S.infantis, S. senftenberg and S.oranienberg were the most frequent aerovars. It might be presumed that the environmental contamination of the area by the organisms is increasing gradually, since new aerovars of Salmonella, for example S.havana, S.agona, S.london, S. mission and S.cerro etc., which were never found in Nagano prefecture before, were isolated in the area. Effect of addition of the Aluminum sulfate and Polyacrylamide for Salmonella isolation from sewage, were studied. By use of the floe method. Salmonella were more frequently isolated from influent sewage.