1986 年 3 巻 2 号 p. 87-94
The most widely used indicator of the sanitary quality of oyster-growing area sea water and oysters is the coliform group of bacteria.
The present study was undertaken to investigate the correlation between coliform (TC) and fecal coliforms (FC) in oyster-growing area water and oyster in Hiroshima bay.
A total of 1, 116 materials including river water (72), paired samples (522) of oysters and sea water were collected and subjected to counting the coliform group during the winters from 1975 to 1984.
The results obtained may be summarized as follows;
1) Between TC (X) and FC (Y), a linear least-square regression calculation gave log Y=0.779 log X-0.191 and a positive correlation of r=0.82 (p=0.01) in river water, log Y=0.732 log X-0.435 and r=0.88 (p= 0.01) in sea water and log Y=0.913 log X-0.111 and r=0.81 (p=0.01) in oysters.
2) Between TC (X) of sea water and FC (Y) of oysters, a linear gave log Y=0.668 log X+1.339 and r=0.73 (p=0.01).
3) Between FC (X) of sea water and FC (Y) of oysters, a linear gave log Y=0.785 log X+1.878 and r=0.72 (p= 0.01).
4) The FC/TC was 8.9% in river water, 10.0% in sea water, and 3.4% in oysters. The concentrating ratio of FC from sea water to oyster was 43.1 times per 100 g and 100 ml. These data suggest that the level of 70 TC MPN is equivalent to 8.4-14 MPN in sea water and TC and FC of water gave the same correlation coefficients against FC of oysters.