Related Experiment Video
Updated: Jul 5, 2026

Quantification of Heavy Metals and Other Inorganic Contaminants on the Productivity of Microalgae
Published on: July 10, 2015
Direct and indirect effects of pollutants on algae and algivorous ciliates in an aquatic indoor microcosm
Markus Liebig1, Gunnar Schmidt, Daniel Bontje
1ECT Oekotoxikologie GmbH, Boettgerstrasse 2-14, D-65439 Floersheim/Main, Germany. m-liebig@ect.de
Abstract:
An aquatic indoor microcosm was used to study effects of the pesticides parathion-methyl and prometryn on phototrophic flagellates (Cryptomonas sp.) and predatory ciliates (Urotricha furcata). Parathion-methyl caused effects to flagellates and ciliates at the range of low mg L(-1), regardless of whether the organisms were exposed separately or combined in the multi-species test system. Prometryn caused effects on the flagellates at low microg L(-1) concentrations, resulting in a NOEC of 6.9 microg L(-1) in the single-species test and a NOEC of 15.2 microg L(-1) in the multi-species microcosm. For ciliates the NOEC decreased by factor 145 in the multi-species test compared to the NOEC of 2.2 mg L(-1) in the single-species test when exposed to prometryn. The lower NOEC for ciliates exposed to prometryn in the microcosm was most likely caused by an indirect effect due to reduced availability of flagellates as food. The measurement of nutrient concentrations in the test media and organisms facilitated the modelling of effects. The presented aquatic indoor microcosm is considered as a tool which could be standardised and applied as an instrument to provide data for higher tier risk assessment.
Related Concept Videos
Freshwater Microbial Ecology
Microbial Bioremediation of Hydrocarbons
Microbial Wastewater Treatment
Marine Microbial Ecology
Red Algae
Green Algae

