Effects of acetaminophen exposure on behavior and erythrocyte nuclear morphology of juvenile Oreochromis niloticus.

The occurrence of pharmaceuticals in the environment can have undesirable effects on nontarget animals, including fish. The present experiment assessed the effects of subchronic exposure to waterborne acetaminophen (N-acetyl-p-aminophenol) (APAP) on selected behavioral aspects (physical avoidance response, ventilation rate, and food detection rate) and erythrocyte nuclear abnormality (ENA) in juvenile Oreochromis niloticus. Two groups of fish were exposed to APAP dissolved in aged municipal water (T1: 2 mg/L and T2: 10 mg/L) for 8 weeks in three replicates (n = 7 fish per tank), alongside a control group (C) without APAP. APAP-exposed fish spent significantly (p < .05) longer time to detect food (T1: 32.6 ± 4.55 s and T2: 39.6 ± 4.66 s) compared to the control group (19.9 ± 2.46 s). Both APAP-exposed groups exhibited attenuated physical avoidance responses (76.7%, 68.7%, and 87.3% in T1, T2, and C, respectively) and a lower mean ventilation rate compared to the control group (194.5 ± 15.5, 179.1 ± 11.6, and 233.2 ± 19.0 per min in T1, T2, and C, respectively). The frequency occurrence of ENA types such as bi-nucleated, notched nuclei, lobed nuclei, and blebbed nuclei (except micronuclei) was significantly higher (p < .05) in APAP-exposed groups compared to the control, with more pronounced effects in the T2 group. The study concludes that APAP exposure prompts significant alterations in behavior and erythrocyte nuclear morphology, emphasizing the value of monitoring and regulating the entry of pharmaceuticals, including APAP, into aquatic environments to prevent unintended effects on non-target organisms like Oreochromis niloticus.

Valorization of Glucose-Derived Humin as a Low-Cost, Green, Reusable Adsorbent for Dye Removal, and Modeling the Process.

Glucose can be isomerized into fructose and dehydrated into key platform biochemicals, following the "bio-refinery concept". However, this process generates black and intractable substances called humin, which possess a polymeric furanic-type structure. In this study, glucose-derived humin (GDH) was obtained by reacting D-glucose with an allylamine catalyst in a deep eutectic solvent medium, followed by a carbonization step. GDH was used as a low-cost, green, and reusable adsorbent for removing cationic methylene blue (MB) dye from water. The morphology of carbonized GDH differs from pristine GDH. The removal efficiencies of MB dye using pristine GDH and carbonized GDH were 52% and 97%, respectively. Temperature measurements indicated an exothermic process following pseudo-first-order kinetics, with adsorption behavior described by the Langmuir isotherm. The optimum parameters were predicted using the response surface methodology and found to be a reaction time of 600 min, an initial dye concentration of 50 ppm, and a GDH weight of 0.11 g with 98.7% desirability. The MB dye removal rate optimized through this model was 96.85%, which was in good agreement with the experimentally obtained value (92.49%). After 10 cycles, the MB removal rate remained above 80%, showcasing the potential for GDH reuse and cost-effective wastewater treatment.

Facile Synthesis of Hydrogel-Based Ion-Exchange Resins for Nitrite/Nitrate Removal and Studies of Adsorption Behavior.

This research aimed to create facile, reusable, hydrogel-based anion exchange resins that have been modified with two different amines to test their ability to adsorb nitrate and nitrite in water using batch and continuous systems. In the batch experiment, maximum adsorption capacities of nitrate and nitrite onto poly (ethylene glycol) diacrylate methacryloxyethyltrimethyl ammonium chloride (PEGDA-MTAC) and poly (ethylene glycol) diacrylate 2-aminoethyl methacrylate hydrochloride (PEGDA-AMHC) adsorbents can be obtained as 13.51 and 13.16 mg NO3--N/g sorbent; and 12.36 and 10.99 mg NO2--N/g sorbent respectively through the Langmuir isotherm model. After 15 adsorption/desorption cycles, PEGDA-MTAC and PEGDA-AMHC retained nitrate adsorption efficiencies of 94.71% and 83.02% and nitrite adsorption efficiencies of 97.38% and 81.15% respectively. In a column experiment, modified adsorbents demonstrated adsorption efficiencies greater than 45% after being recycled five times. Proposed hydrogel-based adsorbents can be more effective than several types of carbon-based sorbents for nitrate and nitrite removal in water and have benefits such as reduced waste generation, cost-effectiveness, and a facile synthesis method.

Green Synthesis of Reusable Adsorbents for the Removal of Heavy Metal Ions.

Industrial wastewater often contains heavy metals, like lead, copper, nickel, cadmium, zinc, mercury, arsenic, and chromium. Overdoses of heavy metals will impose a severe threat to human health. Adsorption is the most efficient way of wastewater treatment for eliminating heavy metals. A novel material-reusable hydrogel-based adsorbent was developed in overcoming the regeneration issue. The polyethylene glycol diacrylate-3-sulfopropyl methacrylate potassium salt (PEGDA-SMP) hydrogel performed an ion-exchange rate to remove heavy metals from wastewater in 30-120 min. The adsorption capacity of PEGDA-SMP increases the increasing pH of a solution, in which pH 5 reaches the maximum. Pseudo-second-order adsorption and the Langmuir adsorption model can fully describe the adsorption properties of PEGDA-SMP for heavy metals. PEGDA-SMP prefers to exchange Pb2+ through K+, and its adsorption capacity can achieve 263.158 mg/g. Ag+, Zn2+, Ni2+, and Cu2+ were 227.27, 117.647, 102.041, and 99.010 mg/g, respectively. The hydrated ionic radius of the heavy metal might play an essential role to affect the adsorption preference. The removal efficiency of heavy metals can approach over 95% for each heavy metal. PEGDA-SMP performs rapid desorption and reaches desorption equilibrium in 15 min. After 10 consecutive adsorption-desorption cycles, the adsorption capacity remained over 90%. The hydrogel developed in this study showed reversible heavy metal absorption. Therefore, excellent adsorption-desorption properties of PEGDA-SMP can be potentially extended to industrial wastewater for removing heavy metals.