Pharmaceutical Compounds In Water Research Articles

Removal of pharmaceutical compounds and toxicology study in wastewater using Malaysian fungal Ganoderma lucidum

Elevated usage of pharmaceutical products leads to the accumulation of emerging contaminants in sewage. In the current work, Ganoderma lucidum (GL) was used to remove pharmaceutical compounds (PCs), proposed as a tertiary method in sewage treatment plants (STPs). The PCs consisted of a group of painkillers (ketoprofen, diclofenac, and dexamethasone), psychiatrists (carbamazepine, venlafaxine, and citalopram), beta-blockers (atenolol, metoprolol, and propranolol), and anti-hypertensives (losartan and valsartan). The performance of 800 mL of synthetic water, effluent STP, and hospital wastewater (HWW) was evaluated. Parameters, including treatment time, inoculum volume, and mechanical agitation speed, have been tested. The toxicity of the GL after treatment is being studied based on exposure levels to zebrafish embryos (ZFET) and the morphology of the GL has been observed via Field Emission Scanning Electron Microscopy (FESEM). The findings conclude that GL can reduce PCs from <10% to >90%. Diclofenac and valsartan are the highest (>90%) in the synthetic model, while citalopram and propranolol (>80%) are in the real wastewater. GL effectively removed pollutants in 48 h, 1% of the inoculum volume, and 50 rpm. The ZFET showed GL is non-toxic (LC50 is 209.95 mg/mL). In the morphology observation, pellets GL do not show major differences after treatment, showing potential to be used for a longer treatment time and to be re-useable in the system. GL offers advantages to removing PCs in water due to their non-specific extracellular enzymes that allow for the biodegradation of PCs and indicates a good potential in real-world applications as a favourable alternative treatment.

Peroxyacetic acid activation by cobalt-doped peanut shell biochar for efficient CBZ degradation: Role of organic radicals, singlet oxygen, and high-valent cobalt species

Peroxyacetic acid (PAA) oxidant has a broad application prospect to be combined with biochar in the treatment of organic pollutants due to its excellent characteristics of eco-friendly and easy activation. In this study, peanut shell biochar-loaded Co nanoparticles (Co-BC-850) catalysts were prepared through pyrolysis to activate PAA for carbamazepine (CBZ) degradation. The pyrolysis temperature significantly affected the CBZ degradation efficiency of the catalysts. The experimental results revealed that the Co-BC-850 catalyst exhibited the highest CBZ degradation efficiency. Within 20 min, a CBZ degradation rate of 99.9% was achieved with Co-BC-850 concentration of 50 mg/L and PAA concentration of 1 mM. The Co-BC-850/PAA system achieved high degradation performance for CBZ at a pH ranging from 5.0 to 9.0, even in the presence of inorganic anions. The analysis of the Co-BC-850/PAA system revealed a complex interplay of reactive species (RSs). Organic radicals (R-O•), singlet oxygen (1O2), and high-valent cobalt species (Co(IV)) collaboratively contributed to CBZ degradation. These findings revealed the intricate mechanism of CBZ degradation via Co-BC-850-activated PAA, thereby elucidating potential degradation pathways. This study demonstrates the promising application of biochar PAA-based AOPs and offers a sustainable and effective solution for the degradation of CBZ and other potential pharmaceutical compounds in water.

Petroleum asphaltene-derived highly porous carbon for the efficient removal of pharmaceutical compounds in water

Petroleum asphaltene-derived highly porous carbon for the efficient removal of pharmaceutical compounds in water

Presence and distribution of selected pharmaceutical compounds in water and surface sediment of the Golden Horn Estuary, Sea of Marmara, Turkey

The presence and distribution of ketoprofen, fenoprofen, diclofenac ibuprofen, naproxen, gemfibrozil, clofibric acid, estrone, 17β-estradiol, 17α-ethinylestradiol, and carbamazepine were investigated in water and surface sediment of the Golden Horn Estuary (Sea of Marmara, Turkey). Water samples were collected seasonally from different depths in nine sampling stations. Surface sediment samples were taken at four stations once a year. Liquid–liquid and solid-phase extraction (SPE) methods were performed on water samples. Sediment samples were extracted by ultrasonic extraction and then SPE method was applied for clean-up. Subsequently, all samples were analyzed by High-Performance Liquid Chromatography (HPLC). The most dominant compounds were found as gemfibrozil (<0.054-3.18 μg L−1), fenoprofen (<0.017-1.28 μg L−1), ibuprofen (<0.015-2.46 μg L−1) and 17α-ethinylestradiol (<0.010-1.49 μg L−1) in water samples. Only five of these eleven studied pharmaceuticals in surface sediments of the Golden Horn Estuary were able to identify. 17α-ethinylestradiol (319 ng g−1), fenoprofen (242 ng g−1), ibuprofen (215 ng g−1), gemfibrozil (124 ng g−1), carbamazepine (118 ng g−1) were detected in the surface sediments. Diclofenac, ketoprofen, naproxen, clofibric acid, estrone and 17β-estradiol were found below the method detection limits in surface sediments. Generally, the environmental concentrations of pharmaceuticals in water and surface sediment were much higher than those reported worldwide.

Quantification of selected pharmaceutical compounds in water using liquid chromatography-electrospray ionisation mass spectrometry (LC-ESI-MS)

The detection and quantitation of pharmaceutical compounds (PCs) in different environmental matrices is still a challenge, due to their extremely low (ng-μg) concentrations and the lack of rapid and sensitive analytical techniques. A number of techniques, such as enzyme-linked immunosorbent assay (ELISA), chromatography, electrophoresis, and electrochemical methods have been explored. These methods are limited by their poor sensitivity. In this study, a hyphenated liquid chromatography-mass spectrometric (LC-MS) method was developed, validated, and tested for the detection and quantification of seven active pharmaceutical compounds, with solid-phase extraction for analytes recovery and separation of interference from the aqueous matrix. The sensitivity achieved for the method allowed for LODs (μg/L) of 0.0439, 0.0684, 0.1219, 0.0710, 0.1129, 0.0447, 0.0837 and LOQs (μg/L) of 0.1462, 0.2281, 0.4065, 0.2367, 0.3763, 0.1492, 0.2792, for lamivudine, acetaminophen, vancomycin, ciprofloxacin, sulfamethoxazole, diclofenac, and ivermectin, respectively, within a linear range of 0.01–0.1 μg/mL. Other ICH validation parameters are also discussed. The different PCs were positive in 61 % of the tested surface waters, with diclofenac present only in two of the sampling points. The concentrations at which they occurred were variable and ranged between ND and 398.98 μg/L.

Occurrence, distribution, and ecotoxicological risk assessment of selected pharmaceutical compounds in water from Lake Victoria, Uganda

The occurrence of 24 pharmaceuticals (including 15 antibiotics, three analgesic/anti-inflammatory drugs, three anti-epileptic/antidepressant drugs, two beta blockers, and one lipid regulator) was investigated in 75 water samples collected from four bays in the Ugandan part of Lake Victoria. In addition, the potential environmental risk of the target pharmaceutical compounds to aquatic organisms in the aquatic ecosystem of Lake Victoria was assessed. Water samples were extracted using solid phase extraction and analyzed for pharmaceuticals using high-performance liquid chromatography coupled with triple quadrupole mass spectrometry (LC/MS/MS). Eighteen of the 24 pharmaceuticals occurred at quantifiable concentrations. Sulfamethoxazole (1–5600 ng L−1), trimethoprim (1–89 ng L−1), tetracycline (3–70 ng L−1), sulfacetamide (1–13 ng L−1), and ibuprofen (6–780 ng L−1) occurred at quantifiable concentrations in all water samples. Sulfamethazine (2–50 ng L−1), erythromycin (10–66 ng L−1), diclofenac (2–160 ng L−1), and carbamazepine (5–72 ng L−1) were only quantifiable in water samples from Murchison Bay. The highest concentrations of pharmaceuticals were found in Murchison Bay, the main recipient of sewage effluents, industrial and municipal waste from Kampala city via the Nakivubo channel. Ecotoxicological risk assessment showed that sulfamethoxazole, oxytetracycline, erythromycin, and diclofenac pose a high toxic risk to aquatic organisms in the lake, while ciprofloxacin, norfloxacin, and ibuprofen pose a medium risk. This study is the first of its kind to report the levels and ecotoxic risks of pharmaceutical compounds in Lake Victoria waters, of Uganda, and East Africa as a whole.

Novel phenyl-phosphate-based porous organic polymers for removal of pharmaceutical contaminants in water

A clean water system is a basic necessity for the survival of living organisms, and thus, addressing the removal of emerging contaminants from aquatic systems is a priority research topic to reinstate the ecosystem balance for a sustainable future. In this study, we have synthesized two types of novel phosphate based porous organic polymers (P-POP-1 and P-POP-2) by one-pot straightforward synthesis with a Friedel-Crafts reaction using diphenyl phosphate and 1,1,2,2-tetraphenylethylene as precursors for P-POP-1, and diphenyl phosphate and 1,3,5-triphenylbenzene for P-POP-2. A series of material characterization using powder X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, N2 adsorption-desorption, and thermal gravimetric analysis showed that P-POP-1 and P-POP-2 have porous structures with intact phosphates and show a specific surface area of 714 and 581 m2/g, and mesoporosity of 19.6% and 32.5%, respectively. Using caffeine, diclofenac, and carbamazepine as three target pharmaceutical compounds, P-POP-2 showed excellent maximum adsorption capacity (caffeine 301 mg/g, diclofenac 217 mg/g, and carbamazepine 248 mg/g). P-POP-2 also exhibited an adsorption equilibrium time of 50 min, which is shorter than those of other materials. Furthermore, P-POP-2 exhibited high pharmaceutical compound removal (>95% for caffeine and carbamazepine; >82% for diclofenac) in the presence of other competing cations and humic acid. The repeated use of P-POPs over 5 cycles showed <10% deterioration in adsorption capacities. Results from this study show that phosphate-based porous organic polymer material could be a promising adsorbent for removing pharmaceutical compounds in water.

Degradation of pharmaceutical compounds in water by oxygenated electrochemical oxidation: Parametric optimization, kinetic studies and toxicity assessment.

The pharmaceutical compounds sulfamethoxazole (SMX), propranolol (PRO) and carbamazepine (CBZ) are biorecalcitrant and frequently detected in waters causing negative impacts on human health and aquatic organisms. Electrochemical oxidation appears as an effective option for the removal of recalcitrant compounds and its enhancement is an important issue for the removal of emerging compounds in water. The contribution of this research lies in the comprehensive analysis of the oxygenated electro chemical oxidation of CBZ, SMX and PRO using Nb/BDD mesh anode. The effect of treatment time, current, pH and oxygen injection on the SMX, PRO and CBZ degradation was assessed using Na2SO4 as electrolyte, process optimization was performed, by-products were identified, kinetic and toxicity tests were carried out using different electrolytes. Finally, the process effectiveness was tested using real secondary effluent spiked with the mixture of the pharmaceutical compounds and the acute toxicity was determined. The obtained results indicated that the oxygenated electrochemical oxidation allows effective simultaneous SMX, PRO and CBZ degradation, which showed a significant dependence of treatment time, current and oxygen injection in Na2SO4 electrolyte. At 90 min of electrolysis the parent compounds were detected as well as eight by-products. At 150 min of treatment, further to the already determined by-products and the parent compounds, appeared phenol and p-benzoquinone. Based on the identified compounds, degradation pathways were explained as a result of two main mechanisms: transformation (hydroxylation, deamination, desulfunation) and bond rupture. The kinetic study indicated an increase of the first-order kinetic constant in the oxygenated electrochemical oxidation process using Na2SO4 and NaBr as electrolyte, nevertheless the constant decreased in the presence of NaCl. In the assays with secondary effluent spiked with SMX, PRO and CBZ, the oxygenation did not enhance the performance of the process, however; pharmaceuticals were degraded with a higher removal rates compared with the ones determined in the Na2SO4 synthetic solutions assays; the oxygenation enhanced the TOC and COD removal. The acute toxicity of spiked secondary effluent was reduced from the first few minutes of the electrochemical oxidation process.

Degradation of diclofenac by electron beam irradiaton: Toxicitiy removal, by-products identification and effect of another pharmaceutical compound

Water contamination by the anti-inflammatory drug diclofenac (DCF) is a consequence of its incomplete removal in wastewater and sewage treatment plants, which is potentialized by interactions with other pharmaceutical contaminants. In this context, electron beam irradiation (EBI) has been considered a clean technology for degrading pharmaceutical compounds in water. Nevertheless, the identification of DCF by-products and their correlation with biological recalcitrance and acute toxicity are poorly understood. In this study, the V. fischeri test was used to characterize DCF toxicity in the absence and presence of fluoxetine (FLX), prior and after irradiation. The results showed complete DCF degradation at low dose (5 kGy). DCF concentration followed pseudo first-order decay with respect to the absorbed, with k0 = (1.33 ± 0.10) kGy−1 (DCF) and k0 = (0.90 ± 0.12) kGy−1 (DCF + FLX). In contrast, negligible TOC removal was observed even at 7.5 kGy, with the formation of recalcitrant, non-biodegradable by-products, as also suggested by the respirometry test. Despite that, the toxicity of the DCF solution diminished from (19.6 ± 1.6) TU to (6.2 ± 2.3) TU, and from (6.8 ± 0.9) TU to (3.1 ± 0.2) TU, in the absence and presence of FLX, respectively, after irradiation up to 5 kGy. Four of the eleven by-products identified by direct-injection MS were easily degraded by EBI, and one (C13H14ClNO5) was considered the least recalcitrant but the most toxic. Based on these results, a possible DCF degradation pathway is proposed, involving hydroxylation and oxidation of aromatic rings, dehalogenation and C − N bond cleavage.

Removal of pharmaceutical compounds in water and wastewater using fungal oxidoreductase enzymes.

Due to recalcitrance of some pharmaceutically active compounds (PhACs), conventional wastewater treatment is not able to remove them effectively. Therefore, their occurrence in surface water and potential environmental impact has raised serious global concern. Biological transformation of these contaminants using white-rot fungi (WRF) and their oxidoreductase enzymes has been proposed as a low cost and environmentally friendly solution for water treatment. The removal performance of PhACs by a fungal culture is dependent on several factors, such as fungal species, the secreted enzymes, molecular structure of target compounds, culture medium composition, etc. In recent 20 years, numerous researchers tried to elucidate the removal mechanisms and the effects of important operational parameters such as temperature and pH on the enzymatic treatment of PhACs. This review summarizes and analyzes the studies performed on PhACs removal from spiked pure water and real wastewaters using oxidoreductase enzymes and the data related to degradation efficiencies of the most studied compounds. The review also offers an insight into enzymes immobilization, fungal reactors, mediators, degradation mechanisms and transformation products (TPs) of PhACs. In brief, higher hydrophobicity and having electron-donating groups, such as amine and hydroxyl in molecular structure leads to more effective degradation of PhACs by fungal cultures. For recalcitrant compounds, using redox mediators, such as syringaldehyde increases the degradation efficiency, however they may cause toxicity in the effluent and deactivate the enzyme. Immobilization of enzymes on supports can enhance the performance of enzyme in terms of reusability and stability. However, the immobilization strategy should be carefully selected to reduce the cost and enable regeneration. Still, further studies are needed to elucidate the mechanisms involved in enzymatic degradation and the toxicity levels of TPs and also to optimize the whole treatment strategy to have economical and technical competitiveness.

Removal of sulfamethoxazole and diclofenac from water: strategies involving O3 and H2O2

ABSTRACTDiclofenac (DCF) and Sulfamethoxazole (SMX) are two of the most frequently detected pharmaceutical compounds in water and are hardly removed by biological treatment systems. The presence of H2O2 was investigated in the ozonation of these two compounds. Experiments were carried out with both using distilled water and secondary effluent from a municipal wastewater treatment plant spiked with pharmaceuticals. Chemical oxygen demand (COD) abatement rate improved when H2O2 was added at the beginning of the ozonation process and when the ozone inlet concentration increased, attaining a maximum value of 91% and simultaneously a lower ozone waste for a H2O2 initial concentration of 5 mM and an ozone inlet concentration of 20 g Nm−3. For these operation conditions, the water matrix has no significant impact on SMX and DCF removal, which were totally degraded in 45 and 60 min, respectively. Nevertheless, lower COD degradation and ozone usage were obtained when the secondary effluent was used. Inorganic ions such as chloride, sulphate and nitrate and short-chain organic compounds were detected as by-products of the SMX and DCF oxidation. Vibrio fischeri luminescence inhibition tests revealed that simultaneous use of ozone and H2O2 reduced acute toxicity.

Simple and quick determination of analgesics and other contaminants of emerging concern in environmental waters by on-line solid phase extraction coupled to liquid chromatography–tandem mass spectrometry

A simple and quick analytical method has been developed for the determination of pharmaceutical compounds in water. An on-line solid-phase extraction (SPE) coupled to liquid chromatography–tandem mass spectrometry (LC–MS/MS) method has been optimized to determine 7 contaminants of emerging concern in environmental waters at ngL−1 levels. This procedure requires minimal sample handling and small sample volume (900μL) with a total running time of 18min. Several SPE parameters were evaluated and optimized in order to achieve a high sample throughput. Therefore sample volume, carryover and reusability of the cartridges were evaluated. Performance characteristics were evaluated and good linearity was obtained (R2>0.98). Recoveries were evaluated in spiked samples at three concentrations and the values ranged from 71 to 104%. Intra and inter-day precision was lower than 10 and 13% respectively. Limits of quantification were equal to or lower than 10ngL−1, except for 1,7-dimethylxanthine (20ngL−1) and ibuprofen (50ngL−1). The method was applied to 20 environmental water samples, and ibuprofen was the compound most widely detected at concentrations up to 42.06μgL−1, whereas the other compounds were detected in fewer samples at lower concentrations (up to 15.99μgL−1).

Enhanced photocatalytic degradation of norfloxacin in aqueous Bi2WO6 dispersions containing nonionic surfactant under visible light irradiation

Photocatalytic degradation is an alternative method to remove pharmaceutical compounds in water, however it is hard to achieve efficient rate because of the poor solubility of pharmaceutical compounds in water. This study investigated the photodegradation of norfloxacin in a nonionic surfactant Triton-X100 (TX100)/Bi2WO6 dispersion under visible light irradiation (400–750nm). It was found that the degradation of poorly soluble NOF can be strongly enhanced with the addition of TX100. TX100 was adsorbed strongly on Bi2WO6 surface and accelerated NOF photodegradation at the critical micelle concentration (CMC=0.25mM). Higher TX100 concentration (>0.25mM) lowered the degradation rate. In the presence of TX100, the degradation rate reached the maximum value when the pH value was 8.06. FTIR analyses demonstrated that the adsorbed NOF on the catalyst was completely degraded after 2h irradiation. According to the intermediates identified by HPLC/MS/MS, three possible degradation pathways were proposed to include addition of hydroxyl radical to quinolone ring, elimination of piperazynilic ring in fluoroquinolone molecules, and replacement of F atoms on the aromatic ring by hydroxyl radicals.

Integration of ozone and solar TiO2-photocatalytic oxidation for the degradation of selected pharmaceutical compounds in water and wastewater

The degradation of a mixture of four pharmaceutical compounds (atenolol, hydrochlorothiazide, ofloxacin and trimethoprim) in distilled water and in a synthetic solution simulating a typical secondary effluent from a municipal wastewater treatment plant by ozonation, solar TiO2-photocatalytic oxidation and a sequence of both methods has been investigated. Degradation by ozone led to the complete removal of the selected emerging compounds (EC) but an accumulation of ozonation by-products (e.g., phenolic intermediates and carboxylic acids) in solution was observed. The presence of ozone-consuming substances in the synthetic effluent had not a negative impact on the removal of the pharmaceuticals but on their mineralization (TOC removal <8%). By photocatalytic oxidation, the pharmaceutical compounds were completely removed with UVA radiation doses lower than 0.3kJ per mg EC while about 70% TOC conversion was achieved with a UVA radiation dose of 1kJ per mg EC. The presence of organic and inorganic matter in the secondary effluent had a negative impact on the mineralization of pharmaceuticals. Thus, initial TOC removal rate was five times lower when treating the pharmaceuticals in the synthetic effluent compared to distilled water. The application of a sequential ozone – TiO2 solar photocatalytic oxidation treatment allowed complete removal of pharmaceuticals by ozonation and further mineralization of ozonation by-products by the photocatalytic treatment.

Solar photocatalytic ozonation of a mixture of pharmaceutical compounds in water

Aqueous solutions of mixtures of four pharmaceutical compounds (atenolol, hydrochlorothiazide, ofloxacin and trimethoprim) both in Milli-Q ultrapure water and in a secondary effluent from a municipal wastewater treatment plant have been treated at pH 7 by different oxidation methods, such as conventional ozonation, photolytic ozonation, TiO2 catalytic ozonation, TiO2 photocatalytic oxidation and TiO2 photocatalytic ozonation. Experiments were carried out using a solar compound parabolic concentrator. The performance results have been compared in terms of removal of emerging contaminants (ECs), generation rate of phenolic intermediates, organic matter mineralization, ecotoxicity removal and enhancement of biodegradability. Also, the consumption of ozone to achieve certain treatment goals (95% removal of ECs and 40% mineralization) is discussed. Results reveal that solar photocatalytic ozonation is a promising oxidation method as it led to the best results in terms of EC mineralization (∼85%), toxicity removal (∼90%) and efficient use of ozone (∼2mgO3mgEC−1 to achieve complete EC removal and ∼18mgO3mgTOC−1 to achieve 40% EC mineralization, respectively).

Synthesized Magnetic Manganese Ferrite Nanoparticles on Activated Carbon for Sulfamethoxazole Removal

The presence of pharmaceutical compounds in water has adverse environmental and health impacts. The main objective of the current research are to investigate the removal efficiency of sulfamethoxazole (SMX) from aqueous solution by using magnetic manganese ferrite nanoparticles synthesized on powdered activated carbon (PAC). Magnetic activated carbon composites (MACC) were prepared by using chemical co‐precipitation at different temperature values ranging from 298 to 423 K. The obtained samples were characterized by contemporary characterization instrumental methods of analysis, and their SMX removal capabilities were evaluated. Results revealed that the procedure successfully created magnetic nanoparticles on PAC at temperatures of 298–423 K, and the anchored MnFe2O4/MnO2 manifested more crystalline forms at 423 K. As a result, MACC prepared at 423 K showed the highest magnetic and sorption capacities among three obtained samples. The SMX maximal adsorption capacity of MACC(423K) was 159 mg/g at pH 7, and the SMX adsorption remained stable at pH 3–7. The effect of common ions and humic acids on SMX adsorption indicates a high selectivity of MACC(423K) for SMX. Furthermore, MACC(423K) achieved much higher regeneration efficiency by H2O2 than that of virgin PAC, due to the presence of MnFe2O4/MnO2.

Field-scale monitoring of pharmaceutical compounds applied to active golf courses by recycled water.

The scarcity of potable water in arid and semiarid environments has led to the wider use of recycled water for irrigating agricultural fields, parks, golf courses, and other areas. One concern using recycled water as a source of irrigation has been the presence, fate, and transport of pharmaceutical compounds in water that percolates below the root zone of plants; however, very few multiyear field studies have been reported in the peer-reviewed literature. Here, we assessed compound mass flux of 13 pharmaceuticals in the fairways of four golf courses in the southwestern United States during a 2-yr field study. The sites varied by climate and soil type but were similar regarding turfgrass management. The results showed the presence of at least one pharmaceutical compound in nearly all samples collected, although concentrations were substantially lower after transport through the soil. Percent reduction in compound mass fluxes in drainage water was effectively 100% in 22 of 52 cases, 98 to 100% in 27 of 52 cases, and 73 to 94% in 3 of 52 cases (a case is defined as a specific compound measured at a specific site). Mass fluxes migrating below the root zone were calculated as <250 × 10 g ha for all compounds and >100 × 10 g ha in only two cases. For cases where the majority of the analyses were reportable, all fluxes were <8.80 × 10 g ha. Carbamazepine, meprobamate, and sulfamethoxazole were most commonly found in drainage water, representing nearly 80% of all reportable detections. This research demonstrates the potential of turfgrass/soil systems to reduce contaminant loading below the root zone and potentially toward groundwater.

Assessment of the kinetics of oxidation of some steroids and pharmaceutical compounds in water using ozone

Emerging contaminants are present in surface and ground water, generating a potential risk for the public health of surrounding populations that consume contaminated water. However, their elimination using conventional treatment methods has not been an easy task. The aim of this research was the assessment of the kinetics of oxidation of four emerging contaminants in water two steroids: estradiol (E2) and ethynilestradiol (EE2) and two pharmaceutical drugs: naproxen (NPX) and ibuprofen (IBP) – by using an ozonation process. The stoichiometry and the second order rate constants for the four compounds were obtained. The method of competitive kinetics was established to assess the kinetics of oxidation of steroids and NPX and the absolute rate constant under pseudo-first-order conditions method for IBP. The second order rate constants for E2, EE2, NPX were in the order of 104 to 105L/(mols) and for IBP the value was 101L/(mols). An oxidation kinetic model for the steroids and pharmaceutical drugs at different doses of ozone was obtained from the rate constants, and validated with the experimental values. In addition, the half-life of the selected compounds for each experimental ozone dose was obtained, which serves to predict the behavior of oxidation of emerging contaminants, knowing the initial concentration of ozone. This research is focused toward a project for water treatment with the presence of emerging contaminants on a semi-pilot scale in continuous operation.

Issue of Pharmaceutical Compounds in Water and Wastewater: Sources, Impact and Elimination

Issue of Pharmaceutical Compounds in Water and Wastewater: Sources, Impact and Elimination

Quantitative on-line preconcentration-liquid chromatography coupled with tandem mass spectrometry method for the determination of pharmaceutical compounds in water

One of the current environmental issues concerns the presence and fate of pharmaceuticals in water bodies as these compounds may represent a potential environmental problem. The characterization of pharmaceutical contamination requires powerful analytical method able to quantify these pollutants at very low concentration (few ngL−1).In this work, a multi-residue analytical methodology (on-line solid phase extraction-liquid chromatography–triple quadrupole mass spectrometry using positive and negative electrospray ionization) has been developed and validated for 40 multi-class pharmaceuticals and metabolites for tap and surface waters. This on-line SPE method was very convenient and efficient compared to classical off-line SPE method because of its shorter total run time including sample preparation and smaller sample volume (1mL vs up to 1L). The optimized method included several therapeutic classes as lipid regulators, antibiotics, beta-blockers, non-steroidal anti-inflammatories, antineoplastic, etc., with various physicochemical properties. Quantification has been achieved with the internal standards. The limits of detection are between 0.7 and 15ngL−1 for drinking waters and 2–15ngL−1 for surface waters. The inter-day precision values are below 20% for each studied level.The improvement and strength of the analytical method has been verified along a monitoring of these 40 pharmaceuticals in Isle River, a French stream located in the South West of France. During this survey, 16 pharmaceutical compounds have been detected.