Development, Testing and Implementation of Automated Biotests for the Monitoring of the River Rhine, Demonstrated by Bacteria and Algae Tests

A joint research project for the development, testing and implementation of automated biotests, capable of rapidly detecting acutely toxic water conditions of the River Rhine, was carried out by several administrative and scientific institutions in Germany. Automated biomonitors working with the test organisms bacteria, algae, water fleas, mussels, and fishes were tested and compared with respect to their sensitivity, reliability, and practical handling under field conditions. Field trials with atrazine and sodium pentachlorophenolate as toxicants were performed on the River Rhine. Threshold values and LOEC-values (Lowest observed effect concentration) were determined to compare the test specific sensitivity of the test systems. From 1990 to 1992 various biomonitors were tested in monitoring stations on the river Rhine and in a mobile laboratory container on the rivers Rhine and Main. Results of bacteria and algae tests are presented.