Removal Of Pharmaceutical Products Research Articles

Laccases as Effective Tools in the Removal of Pharmaceutical Products from Aquatic Systems.

This review aims to provide a comprehensive overview of the application of bacterial and fungal laccases for the removal of pharmaceuticals from the environment. Laccases were evaluated for their efficacy in degrading pharmaceutical substances across various categories, including analgesics, antibiotics, antiepileptics, antirheumatic drugs, cytostatics, hormones, anxiolytics, and sympatholytics. The capability of laccases to degrade or biotransform these drugs was found to be dependent on their structural characteristics. The formation of di-, oligo- and polymers of the parent compound has been observed using the laccase mediator system (LMS), which is advantageous in terms of their removal via commonly used processes in wastewater treatment plants (WWTPs). Notably, certain pharmaceuticals such as tetracycline antibiotics or estrogen hormones exhibited degradation or even mineralization when subjected to laccase treatment. Employing enzyme pretreatment mitigated the toxic effects of degradation products compared to the parent drug. However, when utilizing the LMS, careful mediator selection is essential to prevent potential increases in environment toxicity. Laccases demonstrate efficiency in pharmaceutical removal within WWTPs, operating efficiently under WWTP conditions without necessitating isolation.

Adsorption Potential of Contaminants with Activated Carbon Monoliths from Dried Fruit Epicarp of Lecythis minor

Lecythis minor is a tree commonly known as Monkey pot tree. Its fruits are composed of urn-shaped epicarps, which are bulky ligneous capsules of slow degradation. Activated carbon monoliths were prepared from this fruit epicarp (bioresidue, the source of lignocellulosic matter) by chemical activation with H3PO4. The activation conditions were optimized using a central composite design, considering parameters of temperature, time, and chemical ratio as variables, and iodine and methylene blue number (IN and MBN), along with yield (Y), as responses. The best conditions for activation were 532°C (T), 1.5 h (t), and 1.5-g H3PO4/1-g raw matter (chemical ratio, CR), with response values of 996 mg I/1-g activated carbon (AC) (IN), 361-mg MB/1-g AC (MBN), and 42% (Y). Likewise, the physicochemical/surface characterization of the activated carbon Lecythis minor (ACLM) allowed establishing that it developed micro- and mesopores (Vmicro=0.72 cm3/g; Vmeso=0.87 cm3/g), as well as ultra-microporosity, a BET surface area of 2,164 m2/g, and a total pore volume of 1.7 cm3/g; also, the removal percentages of the emerging contaminants diclofenac and cephalexin in water were above 96%. It is concluded that fruit epicarp of L. minor is a natural-origin resource to produce AC monoliths, with satisfactory yield, desirable surface development, and high thermal stability, capable of adsorption and removal of pharmaceutical products, and other emergent contaminants from water bodies.

Hydrophobic eutectic solvents: Thermophysical study and application in removal of pharmaceutical products from water

Exposure to persistent contaminants presents a risk to humans and animals. Specifically, the occurrence of drugs in aqueous ecosystems is related to the increase in antimicrobial resistance. Several methods to remove them have been studied but most have cost and toxicity drawbacks. Thus, the study of new eco-sustainable procedures is needed as the liquid–liquid extraction with hydrophobic solvents (ESs). In this study, we prepared six ESs mixtures with thymol (Thy) and octanoic acid (Oct) or decanoic acid (Dec) and evaluated their extractive ability in aqueous mixtures of quercetin (Q), nitrofurantoin (NF), or tetracycline (TC). In addition, we measured, correlated, and modelled both the solid–liquid equilibria of the two systems and seven thermophysical properties of the mixtures. From these calculations, we obtained the melting enthalpies of the eutectic points, isobaric thermal expansibilities, intermolecular free lengths, orientational dipolar parameters, thermodynamic properties of the surface, critical temperatures, and activation energies of viscous flow. The perturbed chain statistical associating fluid theory was found to be suitable for predicting the thermodynamic behaviour of these systems. Next, we determined the solubility of the three drugs both in water and in the eutectic mixtures, as well as the efficiency extraction (EE) of the latter. We obtained the highest extraction efficiency for the equimolar [Thy:Oct] mixture, which was the most polar solvent. The values were: EEQ=97.8%, EENF=84.9%, and EETC=95.0%. Further, performing the procedure with three cycles increased these values above 99%. The results showed the highest hydrophobicity for quercetin and the lowest for nitrofurantoin.

Removal of Pharmaceutical Products in a Constructed Wetland

Background There is growing interest in the natural and constructed wetlands for wastewater treatment. While nutrient removal in wetlands has been extensively investigated, information regarding the degradation of the pharmaceuticals and personal care products (PPCPs) has only recently been emerging. PPCPs are widely distributed in urban wastewaters and can be removed to some extent by the constructed wetlands. The medium-term (3-5 years) behavior of these systems regarding PPCP removal is still unknown. Objectives The efficiency of a Leca-based laboratory-scale constructed wetland planted with Phragmites australis (Cav.) Trin. Ex. Steudel in treating an aqueous solution of the pharmaceuticals, namely, carbamazepine, ibuprofen, and sulfadiazine, was to investigate. Materials and Methods The two pilot-scale constructed wetlands (CW) were operated in parallel; one as an experimental unit (a planted reactor with P. australis) and the other as a control (an unplanted reactor with Leca). Pretreatment and analyses of the carbamazepine, ibuprofen, sulfadiazine, and tissue samples (Leca, P. australis body and P.australis leaf) were conducted using HPLC. Results The carbamazepine, ibuprofen, and sulfadiazine removal efficiencies for the planted and unplanted reactors were 89.23% and 95.94%, 89.50% and 94.73%, and 67.20% and 93.68%, respectively. The Leca bed permitted an efficient removal. Leca has a high sorption capacity for these pharmaceuticals, with removal efficiencies of 93.68-95.94% in the unplanted reactors. Conclusions Sorption processes might be of a major importance in achieving efficient treatment of wastewater, particularly in the removal of organic material that are resistant to biodegradation, in which case the materials composing the support matrix may play an important role. The results obtained in the present study indicate that a constructed wetland with Leca as a substrate and planted with P. australis is effective in the treatment of wastewater contaminated with carbamazepine, ibuprofen, and sulfadiazine.

Biogenic platinum and palladium nanoparticles as new catalysts for the removal of pharmaceutical compounds

Pharmaceutical products (PhP) are one of the most alarming emergent pollutants in the environment. Therefore, it is of extreme importance to investigate efficient PhP removal processes. Biologic synthesis of platinum nanoparticles (Bio-Pt) has been reported, but their catalytic activity was never investigated. In this work, we explored the potential of cell-supported platinum (Bio-Pt) and palladium (Bio-Pd) nanoparticles synthesized with Desulfovibrio vulgaris as biocatalysts for removal of four PhP: ciprofloxacin, sulfamethoxazole, ibuprofen and 17β-estradiol. The catalytic activity of the biological nanoparticles was compared with the PhP removal efficiency of D. vulgaris whole-cells. In contrast with Bio-Pd, Bio-Pt has a high catalytic activity in PhP removal, with 94, 85 and 70% removal of 17β-estradiol, sulfamethoxazole and ciprofloxacin, respectively. In addition, the estrogenic activity of 17β-estradiol was strongly reduced after the reaction with Bio-Pt, showing that this biocatalyst produces less toxic effluents. Bio-Pt or Bio-Pd did not act on ibuprofen, but this could be completely removed by D. vulgaris whole-cells, demonstrating that sulfate-reducing bacteria are among the microorganisms capable of biotransformation of ibuprofen in anaerobic environments. This study demonstrates for the first time that Bio-Pt has a high catalytic activity, and is a promising catalyst to be used in water treatment processes for the removal of antibiotics and endocrine disrupting compounds, the most problematic PhP.

Seasonal occurrence and removal of pharmaceutical products in municipal wastewaters

The occurrence in municipal wastewaters of six pharmaceutical products, paracetamol, ibuprofen, naproxen, diclofenac, caffeine and carbamazepine, which belong to different therapeutic classes (analgesic drugs, anti-inflammatory, antiepileptic and stimulant compounds), have been investigated. Influent and effluent water samples from two conventional wastewater treatment plants (WWTPs) of the North of Spain were collected at different seasons and analyzed. Ranges of PPCPs concentrations were similar to levels reported in other studies worldwide. Influent concentrations ranges were 2.3–42μg/L for ibuprofen and naproxen, 0.04–7.8μg/L for caffeine and paracetamol, and 0.03–0.4μg/L for carbamazepine and diclofenac. The highest concentrations were found for ibuprofen in the untreated municipal wastewaters. Effluent concentrations were always below 5.7μg/L. Diclofenac and carbamazepine persisted in WWTP effluents, whereas paracetamol, ibuprofen, naproxen and caffeine showed removal efficiencies between 75% and 99%. Considering first-order kinetics for the biodegradation of these compounds, apparent kinetic constants were calculated and similar values were obtained for both WWTPs, although one of them resulted to be more sensitive to temperature changes.