FIG. 4.

Sub-lethal ecotoxicity tests performed in a microfluidic environment increase sensitivity of the ecotoxicity bioassays on B. calyciflorus. Comparison between sensitivity of conventional mortality dose-response curves (red areas) and video-microscopy enabled analysis of locomotor activities (blue areas) performed on perfusion-based chip devices with heavy metal copper chloride (a) and 3,4-DCA (b). Super-imposed comparative data sets were normalized to respective control values and depicted as mean values ±SE. Analysis of locomotory activity was performed in the final minute of 24-h exposure. Scores of mortality were obtained using manual counting method according to the standard ROTOXKIT-M test protocol in the last hour of exposure to toxicants. Chip-based devices were actuated at a constant volumetric flow rate of 15 μl/min. EC₁₀ and EC₅₀ values were defined as concentrations of a chemical inducing behavioral change in 10% and 50% of test animals, respectively. LC₁₀ and LC₅₀ values were defined as concentrations of a chemical inducing mortality in 10% and 50% of test animals, respectively.