Protozoans Spirostomum ambiguum

Nalecz-Jawecki, G., K. Demkowicz-Dobrzanski, and J. Sawicki. 1993. Protozoan Spirostomum ambiguum as a highly sensitive bioindicator for rapid and easy determination of water quality. Sci. Total Environ., Suppl. 2 1227-1234. 

Also in use are tests that utilize protozoa. Spirotox uses the protozoan Spirostomum ambiguum as a test organism to determine the quality of water (19). This ciliate is sensitive to many compounds, especially heavy metals, that may be found in wastewater. Other eucaryotes have been used in toxicity monitoring, including algae (5,20), but they are not as widely used as fish or daphnia. 

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