抄録
As part of research on the method of collecting soil samples for mutagenicity measurement, a map of the former Sagamihara City was divided into a square mesh by drawing lines along every latitudinal minute and longitudinal minute. 40 surface soil samples were collected at the intersection points on the map, and the mutagenicity of the samples was examined by the Ames preincubation method using Salmonella typhimurium TA98 and TA100 strains. It was found that the average mutagenicity was 47 rev/g of soil when TA98 was used without S9mix, 87 rev/g of soil when TA98 was used with S9mix, 11 rev/g of soil when TA100 was used without S9mix, and 152 rev/g of soil when TA100 was used with S9mix, all of which were lower than the values reported in past documents, and were approximately the same as values obtained in the countryside. To provide an overview, the geographical distribution of specific mutagenic activity was examined. As a result, mutagenic substances easily detectable with TA98 strain (inducing frame shift type mutations) were found mostly in the center of the former Sagamihara City, whereas mutagenic substances easily detectable with TA100 strain (inducing base pair substitution type mutations) were found to have spread over the whole of Sagamihara City. In order to look for hot spots, and in order to understand the distribution of mutagenicity, a sampling plan using non-arbitrary selection of sites as in the present study was effective.
