Additionally,the influence of pellet numbers and therefore M.hiemalis biomass amount on APAP uptake was also studied.Varying pellet numbers (5,10,25 and 50) were exposed to 30 ng/ml APAP for 24 and 48 h(n=4). Furthermore,a negative control(n=4) consisting of five unexposed pellets,to ensure the absence of APAP in the fungal strain, and a positive control of only 30 ng/mL APAP,to determine the natural degradation rate,was set up and sampled after 24 and 48 h. Mediaand pellet samples were collected after the mentioned exposure periods and processed for LC–MS/MS analysis. APAP extraction was conducted as described above with deionized water as an extraction solvent.