Details zur Publikation

Referenztyp Zeitschriften
DOI / URL Link
Creative Commons Lizenz creative commons licence
Titel (primär) The combined algae test for the evaluation of micture toxicity in environmental samples
Autor Glauch, L.; Escher, B.I.;
Journal / Serie Environmental Toxicology and Chemistry
Erscheinungsjahr 2020
Department ZELLTOX;
Band/Volume 39
Heft 12
Sprache englisch;
POF III (gesamt) T42;
Abstract The combined algae test (CAT) is a 96‐well plate‐based algal toxicity assay with the green algae Raphidocelis subcapitata that combines inhibition of 24h population growth rate with inhibition of photosynthesis detected after 2h and 24h with pulse‐amplitude modulated (PAM) fluorometry using a Maxi‐Imaging PAM. The CAT has been in use for more than a decade but had limitations due to incompatibilities of the measurements of the two biological endpoints on the same microtiter plates. These limitations could be overcome by increasing growth rates and doubling times on black, clear‐bottom 96‐well plates by application of dichromatic red/blue LED illumination. Different robotic dosing approaches and additional data evaluation approaches helped to further expand the applicability domain of the assay. The CAT differentiates between non‐specifically acting compounds and photosynthesis inhibitors, such as photosystem II (PSII)‐herbicides. PSII‐herbicides acted immediately on photosynthesis and showed growth rate inhibition at higher concentrations. If growth was a similar or more sensitive endpoint than photosynthesis inhibition, this was an indication that the tested chemical acted non‐specifically or a mixture or a water sample was dominated by chemicals other than PSII‐herbicides acting on algal growth. We fingerprinted the effects of 45 chemicals on photosynthesis inhibition and growth rate and related the effects of the single compounds to designed mixtures of these chemicals detected in water samples and to the effects directly measured in water samples. Most of the observed effects in the water samples could be explained by known photosystem II inhibitors such as triazines and phenylurea herbicides. The improved setup of the CAT gave consistent results with the previous method but has lower cost, higher throughput and higher precision.
ID 23643
dauerhafte UFZ-Verlinkung
Glauch, L., Escher, B.I. (2020):
The combined algae test for the evaluation of micture toxicity in environmental samples
Environ. Toxicol. Chem. 39 (12), 2496 - 2508