Yoshiaki MANABE

Evaluation of Urban Water Cycle System by Ames Mutagenicity Assay - Aiming at the Recycle of Road Runoff -

Toshiya KOMATSU, Shuji HIMENO and Shoichi FUJITA

For the fulfillment of water requirement of the forthcoming generation in urban areas from the current scenario of inadequate water resources, promotion of alternative sustainable sources of water eg. rainwater (roof and road runoff water), groundwater, and reclaimed water, is a primary forethought. However, various risks are inherent in such options. In this research, we measured mutagen formation potential (MFP) on chlorination of road runoff from a viewpoint of genotoxicity water risk. Ames mutagenicity assay were conducted using S.tyhimurium strain TA100 without S9 mix. MFP of 42 nation-wide river waters were also measured in order to compare the MFP levels with those of road runoff. As the results, MFP of road runoff generally showed high values and the average was 8600 net rev. / L. On the other hand, the middle value of MFP in 42 river waters was 2480 net rev. / L. The results suggest MFP of road runoff should be reduced depending on the utilization.
Soil column reactors were operated for investigating the behavior of MFP of a road runoff in soil treatment. The MFP of the soil column effluent was around 1500 net rev. / L. It was revealed that soil treatment is effective for the removal of mutagen precursor in road runoff.