The mature zebrafish that were used for egg production were free of macroscopically discernible symptoms of infection and disease. Whenever

eggs were required, several spawning traps covered with stainless steel mesh were placed on the bottom of the aquaria in the evening, and eggs were collected the following morning. Spawning and fertilization were initiated by rapidly illuminating the aquaria, which was terminated 1 h later by removing the spawning traps. The fish eggs were collected and rinsed three times in dilution water to remove any residue on the egg’s surface. Subsequently, the eggs were immediately exposed to different treatment solutions. Fertilized and normally developing embryos were selected under a stereomicroscope (×8 to × 50) at 4 h post-fertilization (hpf) (i.e., the

sphere stage of the Fedratinib cost blastula period) and used for exposure experiments. Single AZD8186 TiO2-NPs exposure to zebrafish embryos To determine the concentration of TiO2 in the associated toxicological exposure, we first studied the effect of TiO2-NPs exposure on zebrafish embryo development. The concentration series of TiO2-NPs suspensions were 0, 2.5, 5, 10, 20, and 40 mg/L. These test solutions were prepared by diluting a stock solution of 40 mg/L TiO2-NPs. TiO2-NPs suspensions were freshly prepared before the fish eggs were exposed. Mixture exposure of TiO2-NPs and BPA to zebrafish embryos The associated toxicity test in this study consisted of five simultaneous treatment series: (a) BPA alone, RSL 3 (b) mixtures of BPA and TiO2-NPs, (c) TiO2-NPs alone control, (d) dilution water control, (e) dilution solvent control. Based on the effect of TiO2-NPs alone

on zebrafish mafosfamide embryo development and our preliminary experiments, the exposure concentrations were determined as follows: 10 mg/L TiO2-NPs and different concentrations of BPA (0.5, 1, 2, 5, 10, and 20 mg/L). TiO2-NPs powder was weighed and added to individual BPA solutions. The mixture solutions were sonicated for 30 min and were freshly prepared before the exposure test. The embryo toxicity test procedure The embryo toxicity test procedure followed the OECD guidelines for fish embryo toxicity testing [27, 29]. The selected eggs were transferred to 24-well multiple-well plates with freshly prepared test solutions. In 20 wells, selected eggs were placed individually in 2 mL of the individual test solutions. The remaining 4 wells per plate were filled with 2 mL of the dilution water and one egg per well as an internal control. The pH values of the control samples were 7.8 ± 0.2. Moreover, the dilution solvent was used as a solvent control in another 24-well multiple-well plate. All of the wells were covered with a transparent plastic film and were placed on a shaker (at a speed of 40 rpm) in a climate chamber at 26°C ± 1°C with a 14:10-h light/dark cycle.