Monitoring of River Water Quality using Multiple Yeast Assays Transfected with a Cellular Receptor: Application Examples in Ibaraki Prefecture and Tokyo, Japan

Abstract

Although the existence of chemicals having binding affinities for cellular receptors is becoming known and some of them are detected in environmental samples, their multiple abilities cannot be ascertained by individual measurements of chemicals. To enable monitoring of river water quality from effects on receptors, we attempted to measure the receptor activities of river water samples by multiple yeast assays transfected with a cellular receptor and co-activator. Water samples from rivers subjected substantially to treated sewage (such as Tama River located in Tokyo), rivers flowing in overpopulated centers (Sumida River, Kanda River and Meguro River in Tokyo) and rivers with luxuriant algae (Sakura River in Ibaraki) had higher activities to the human and medaka -estrogen receptors, the human aryl hydrocarbon receptor and the human retinoic acid receptor, respectively. Because these receptor activities were not consistent with the results of commonly used methods for water quality monitoring, the yeast assays are expected to provide new perspectives on estimation of influences by receptor effects to quality surveys of environmental waters.