Pond Snail Eggs as an Indicatory Material for Water Pollution Bioassay Preliminary Experiments

Abstract

1. Pond snail (Radix auricularius Japonicus (JAY)) eggs were used as an indicator organism : indicatory stages and states were normal cell division to larva and anomalies such as stop, retard or deform of development.
2. Several bioassays were made to measure the water pollution around Osaka City in using pond snail eggs. Most of the river waters examined are polluted, and in particular markedly in the River Daini-Neya-Gawa. No cleavage of eggs occur in the heavily polluted water discharged from the Konohana sewage disposal plant.
3. Heavy metals induce stop, retard or deform of development, etc. Various chemicals other than heavy metals also induce the same phenomena.
4. The bioassay to measure water pollution using pond snail eggs has such advantages as simplicity, easiness, speed, high sensitivity, clearness of indicatory features, uniformity, and higher accuracy. The method is available in any season of the year when rear under control.
5. The ranking of inhibitory degrees of polluted water samples upon the development of the egg is proposed tentatively as seen in Table 4.