Аннотация:Pharmaceuticals (mostly antibiotics and non-steroid anti-inflammatory drugs) are hazardous micropollutants (HMP). Incomplete degradation of the HMP leads to their persistence in the environment and a plethora of deleterious effects. Conventional wastewater treatment cannot remove HMP completely, and a promising alternative is comprised by biotechnologies based on microalgae. Bioprospecting of HMP-tolerant strains is a bottleneck for such technologies. Carrying out a full-featured testing procedure for each newly isolated culture is impractical. Rapid screening can save a lot of time, money, and labor by selecting the efficient strains for further characterization or finding the concentration range where the strain exhibits the highest tolerance. The suitability of two well-plate screening techniques, one based on wet spectrophotometric assay of photosynthetic pigments together with an alternative method based on PAM imaging of chlorophyll variable fluorescence, was tested. Five pharmaceuticals (azithromycin, cephtriaxone, amoxiclav, diclofenac, ibuprofen) and five original strains (Micractinium simplicissimum NAMSU F2, Desmodesmus sp. IPPAS S-2014, Chlorella vulgarisIPPAS C-2015, Synechococcus sp. IPPAS B-2053, Lobosphaera sp. IPPAS C-2047) have been involved in the screening. Both approaches proved to be suitable for rapid screening of the tolerance of the studied microalgal strains to the toxicity of the studied pharmaceuticals. The imaging PAM–based technique better resolved the rapid changes in the microalgal cell condition. The wet pigment assay better highlighted the effects developing on the time scale of days. Interestingly, Chlorella and Desmodesmus incubated with a low concentration of the pharmaceuticals displayed some stimulatory effects. Precautions necessary for using these methods including the measurement setup, the choice of light intensity, and other possible caveats are discussed.