Detoxification of fermentable broth with activated biocarbon resulting from pyrolysis of agroforestry residues.

Carbon-like materials from pyrolysis (<500°C) of agricultural leftovers (rice husks, eucalyptus sawdust and peach stones) were submitted to steam activation and the expected adsorbent properties evaluated by means of a chemical method (methylene blue) and physically characterized by scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and surface area (BET). Batch experiments were carried out to check the pH effect on the adsorption of methylene blue, by evaluating the respective equilibrium isotherms (Langmuir, Freundlich and Temkin). The steam-activated biocarbons showed significant adsorbent capacity, which increased along with pH. The best performance was achieved by the activated biocarbon from peach stones, which showed adsorptive properties similar to activated carbon market. The suitable detoxification efficiency of untreated broths with activated biocarbon, and an increase in the required fermentability, supports the potential use of these adsorptive bioproducts from agricultural leftovers. The profitable use of agricultural waste materials is actually a welcome strategy for consolidating the biorefinery concept as well as ensuring planetary sustainability. PRACTITIONER POINTS: Use of biomass residues for detoxification of fermentable broth. The activated biocarbons showed significant adsorbent capacity similar to activated carbon market. The results revealed the potential of the biomass residues as a promising source within bio-refineries.

Antipsychotic drugs in hospital wastewater and a preliminary risk assessment.

The residues of pharmaceutical and personal care products are the cause of increasing concern around the world. The aim of this study was to carry out the quantification of six antipsychotic drugs in hospital wastewater with the aid of liquid chromatography-mass spectrometry and, subsequently, make a preliminary assessment of the environmental risk posed. Dispersive liquid-liquid microextraction and solid phase extraction were optimized by multivariate design and validated in compliance with international guidelines. The extraction procedures were successfully applied to the quantification of the six selected antipsychotics in samples that were formed each day and collected at two main sampling points of the sewage network over the period of a week, in December 2017. Olanzapine (0.31─0.52 µg L-1), clozapine (0.56─0.97 µg L-1), haloperidol (1.43─2.73 µg L-1), risperidone (0.92─0.98 µg L-1) and chlorpromazine (0.52 µg L-1) were found in at least one sampling point. In the case of most analytes, the highest concentrations were determined at sampling point A, which are derived from the psychiatric wing. The environmental risk quotient for clozapine, chlorpromazine and risperidone was ˃600, a very high-risk index, which signals the need for a better control of the emission of antipsychotics and an improvement of the wastewater treatment, especially, with regard to wastewater discharged from the hospital psychiatric wing.

A simultaneous determination of anti-cancer drugs in hospital effluent by DLLME HPLC-FLD, together with a risk assessment.

Currently, there is an increasing use of anti-cancer drugs, and hence their occurrence in the environment must be properly managed, in particular, in the light of their high degree of toxicity. In this study, analytical methods using HPLC-FLD assisted by microextraction and solid phase extraction, were developed and validated for the determination of doxorubicin, daunorubicin, epirubicin and irinotecan in hospital effluent. The validation results show determination coefficients (r2) higher than 0.99 and recovery values between 74% and 105%, with an intraday precision of <15%.The limit of quantification was 1.0 µg L- 1 and there were almost no matrix effects. The methods proposed were employed for the determination of the named chemotherapeutics in effluent samples of the University Hospital of Santa Maria, Brazil and quantified in the range of ≥LOQ ̶ 6.22 µg L-1. A preliminary ecotoxicological risk assessment showed values that were potentially very harmful, and thus, the treatment of the hospital effluents requires special attention.

Occurrence of polycyclic aromatic hydrocarbons in surface water and hospital wastewater.

The main objective of this study was to determine the occurrence of polycyclic aromatic hydrocarbons (PAHs) in surface water samples collected from different points along the stream that flows through the Campus of the Federal University of Santa Maria, RS-Brazil. Before reaching the campus, the water in the stream is already contaminated by wastewater discharged from the surrounding, and once inside the Campus, additional wastewater from a Gas Station situated close to the University hospital. A bench scale photodegradation experiment was conducted of the occurring traces of anthracene, phenanthrene and naphthalene, with the aid of a stirred tank reactor and polymer-supported TiO2 as a catalyst. To prevent loss of the low soluble analytes, it was necessary to add 5% and 10% acetonitrile, as an organic modifier of the synthetic aqueous solutions and real samples, respectively. An experimental design was employed and the best conditions for the photocatalysis of the aqueous solutions and real samples were pH 9 and pH 7, and 35°C and 30°C, respectively. Under optimized conditions, the analytes were completely degraded after 60 min of irradiation. The subproducts of the photocatalysis were identified through gas chromatography/mass spectrometry, and fragmentation routes were proposed. The mean concentrations of PAHs in the polluted surface water and hospital wastewater were relatively high: 3.9 ± 1.7 and 21.5 ± 2.8 µg L-1, respectively. A preliminary risk assessment revealed that the presence of anthracene requires particular attention. The risk posed by the occurrence of PAHs in the surface water and hospital wastewater samples confirms the need for an efficient treatment system.

Determination of statin drugs in hospital effluent with dispersive liquid-liquid microextraction and quantification by liquid chromatography.

Statins are classified as being amongst the most prescribed agents for treating hypercholesterolaemia and preventing vascular diseases. In this study, a rapid and effective liquid chromatography method, assisted by diode array detection, was designed and validated for the simultaneous quantification of atorvastatin (ATO) and simvastatin (SIM) in hospital effluent samples. The solid phase extraction (SPE) of the analytes was optimized regarding sorbent material and pH, and the dispersive liquid-liquid microextraction (DLLME), in terms of pH, ionic strength, type and volume of extractor/dispersor solvents. The performance of both extraction procedures was evaluated in terms of linearity, quantification limits, accuracy (recovery %), precision and matrix effects for each analyte. The methods proved to be linear in the concentration range considered; the quantification limits were 0.45 µg L-1 for ATO and 0.75 µg L-1 for SIM; the matrix effect was almost absent in both methods and the average recoveries remained between 81.5-90.0%; and the RSD values were <20%. The validated methods were applied to the quantification of the statins in real samples of hospital effluent; the concentrations ranged from 18.8 µg L-1 to 35.3 µg L-1 for ATO, and from 30.3 µg L-1 to 38.5 µg L-1 for SIM. Since the calculated risk quotient was ≤192, the occurrence of ATO and SIM in hospital effluent poses a potential serious risk to human health and the aquatic ecosystem.

Occurrence of cocaine and metabolites in hospital effluent - A risk evaluation and development of a HPLC method using DLLME.

A fast method for the determination of cocaine and its metabolites in hospital effluent samples was worked out by using liquid chromatography with the aid of fluorescence and diode array detection. Solid phase extraction and dispersive liquid -liquid microextraction were employed during the sample preparation stage. The experiment was conducted by using Chromabond® C18 ec 6 ml/500 mg cartridges, with recoveries higher than 96.6%, 88.3%, 78.7%, and LOQm 0.15; 0.18 and 0.30 µg L-1 for cocaine, benzoylecgonine and anhydroecgonine respectively. In the case of DLLME, different chemical conditions and solvent combinations were tested to find the best settings for the microextraction: pH 9; addition of 0.3 mol L-1 NaCl; 150 µL extractor (chloroform) and 350 µL disperser (methanol). The recoveries for cocaine were as high as 98.3% with LOQm 0.3 µg L-1. After validation, these methods were applied to quantification of the analytes. While the concentration of the anhydroecgonine, (the main pyrolytic metabolite of cocaine), remained below the limit of detection, the range of concentrations of cocaine and benzoylecgonine determined were 0.4-4.9 µg L-1 and 0.9-8.6 µg L-1, respectively. The occurrence has a relatively median/high environmental impact. These concentration values suggest that a role is played by other sources of cocaine, probably related to transport, or handling and the consumption of the drug. The outcome is that cocaine can be quantified by using DLLME as well as SPE, however, DLLME offered clear benefits like simplicity, affordability, and speed, as well as only requiring a small volume of solvents and samples.

Determination of the psychoactive drugs carbamazepine and diazepam in hospital effluent and identification of their metabolites.

This study addresses the occurrence of carbamazepine and diazepam and their metabolites in the wastewater of the University Hospital (HUSM) of the Federal University of Santa Maria, RS-Brazil. Samples were collected from three sampling points of the sewage treatment system: point A ('emergency effluent'), point B ('general effluent') and point C ('water course-receptor'). Eight metabolites were identified: carbamazepine-10-11-epoxide, 10-dihydro-carbamazepine, 2-OH-carbamazepine, iminoquinone, acridone, nordiazepam, oxazepam and temazepam. The mean concentrations in the emergency, general effluent and water course-receptor were as follows: 433.0 ± 4.7, 349.0 ± 5.0 and 485.0 ± 5.6 ng L(-1), for carbamazepine and 550.0 ± 4.3, 441.0 ± 7.9 and 586.6 ± 9.3 ng L(-1), for diazepam, respectively. Liquid chromatography with electrospray ionization tandem mass spectrometry (LC-QqLIT-MS) proved to be a method fit-to-purpose. The determination of carbamazepine and diazepam, and the identification of active metabolites showing environmental persistence (carbamazepine-10-11-epoxide, nordiazepam and oxazepam) revealed the need for a more effective treatment of the HUSM effluent. As far as we know, no similar study has been carried out on the wastewater of Brazilian hospitals.

Determination of anti-anxiety and anti-epileptic drugs in hospital effluent and a preliminary risk assessment.

In this study, an analytical methodology was developed for the determination of psycho-active drugs in the treated effluent of the University Hospital at the Federal University of Santa Maria, RS - Brazil. Samples were collected from point A (Emergency) and point B (General effluent). The adopted methodology included a pre-concentration procedure involving the use of solid phase extraction and determination by liquid chromatography coupled to mass spectrometry. The limit of detection for bromazepam and lorazepam was 4.9 ± 1.0 ng L(-1) and, for carbamazepine, clonazepam and diazepam was 6.1 ± 1.5 ng L(-1). The limit of quantification was 30.0 ± 1.1 ng L(-1), for bromazepam, clonazepam and lorazepam; for carbamazepine was 50.0 ± 1.8 ng L(-1) and was 40.0 ± 1.0 ng L(-1) for diazepam. The mean concentrations in the Emergency and General effluent treated currents were as follows: for bromazepam, 195 ± 6 ng L(-1) and 137 ± 7 ng L(-1); for carbamazepine, 590 ± 6 ng L(-1) and 461 ± 10 ng L(-1); for diazepam, 645 ± 1 ng L(-1) and 571 ± 10 ng L(-1); for lorazepam, 96 ± 7 ng L(-1) and 42 ± 4 ng L(-1); and for clonazepam, 134 ± 10 ng L(-1) and 57 ± 10 ng L(-1). A preliminary risk assessment was conducted: carbamazepine and diazepam require considerable attention owing to their environmental toxicity. The occurrence of these psychoactive-drugs and the environmental risks that they pose demonstrated the need for a more efficient treatment system. As far we are aware, there have been no comparable studies to this on the hazards of hospital effluents in Brazil, and very few that have carried out a risk assessment of psycho-active drugs in hospital effluent in general.

Oxidation-coagulation of ß-blockers by K2FeVIO4 in hospital wastewater: assessment of degradation products and biodegradability.

This study investigated the degradation of atenolol, metoprolol and propranolol beta-blockers by ferrate (K2FeO4) in hospital wastewater and in aqueous solution. In the case of hospital wastewater, the effect of the independent variables pH and [Fe(VI)] was evaluated by means of response surface methodology. The results showed that Fe(VI) plays an important role in the oxidation-coagulation process, and the treatment of the hospital wastewater led to degradations above 90% for all the three ß-blockers, and to reductions of aromaticity that were close to 60%. In addition, only 17% of the organic load was removed. In aqueous solution, the degradation of the ß-blockers atenolol, metoprolol and propranolol was 71.7%, 24.7% and 96.5%, respectively, when a ratio of 1:10 [ß-blocker]:[Fe(VI)] was used. No mineralization was achieved, which suggests that there was a conversion of the ß-blockers to degradation products identified by liquid chromatography/mass spectrometry tandem. Degradation pathways were proposed, which took account of the role of Fe(VI). Furthermore, the ready biodegradability of the post-process samples was evaluated by using the closed bottle test, and showed an increase in biodegradability. The use of the ferrate advanced oxidation technology seems to be a useful means of ensuring the remediation of hospital and similar wastewater.

PDMS extraction bars for the determination of volatile aromatic hydrocarbons in water and wastewater.

In this study, the preparation and application of extraction bars of PDMS were investigated to preconcentrate and determine benzene, toluene, ethylbenzene, and xylene in water and wastewater by means of HPLC with fluorescence detection. Aliquot samples from hospital wastewater were used as the model effluent. The independent variables for the sorptive extraction were as follows: ionic strength (added amounts of NaCl); pH; temperature and time of absorption; temperature and time of desorption. Under optimized conditions, by using a factorial design, the suspended extraction bars could allow the determination of benzene, toluene, ethylbenzene, and xylene (1.20 ± 0.05 µg/L; 10.40 ± 0.02 µg/L; 1.80 ± 0.04 µg/L; 15.9 ± 0.04 µg/L, respectively) in hospital effluent (fortified samples), by recoveries of 71.9 ± 4.9 to 74.8 ± 5.6%. This procedure represents an innovation that eliminates the time-consuming stage of vacuum microfiltration, and allows the determination of volatile organic compounds by HPLC. As far as we know, this procedure is original and represents an important contribution to the field.

Removal of dexamethasone from aqueous solution and hospital wastewater by electrocoagulation.

This study is concerned with the removal of the anti-inflammatory dexamethasone from aqueous solution and hospital wastewater by electrocoagulation. The variation of the toxicity during the electrocoagulation was also studied through experiments that were designed and optimized by means of response surface methodology. The coagulation efficiency was evaluated by measuring the dexamethasone concentration by high performance liquid chromatography coupled to a diode array detector. In addition, variation was evaluated through a Vibrio fischeri test. The results showed an increase in the removal of dexamethasone (up to 38.1%) with a rise of the current applied and a decrease of the inter-electrode distance, in aqueous solutions. The application to hospital effluent showed similar results for the removal of dexamethasone. The main effect of the electrocoagulation was that it removed colloids and reduced the organic load of the hospital wastewater. Regarding the current applied, the calculated energy efficiency was 100%. Without pH adjustment of the aqueous solution or hospital wastewater, the residual aluminum concentration always remained lower than 10 mg L(-1), and, with adjustment (to pH 6.5), lower than 0.30 mg L(-1), at the final stage. No toxicity variation was observed during the electrocoagulation process in aqueous solution, either in the presence or absence of dexamethasone.

Nonylphenol polyethoxylate in hospital wastewater: a study of the subproducts of electrocoagulation.

Chromatographic procedures such as solid phase extraction and high performance liquid chromatography coupled with a fluorescence detector (SPE-HPLC-FLD), were carried out to determine the concentrations of the surfactant nonylphenol ethoxylate (9 ethylene oxide units, NP9EO) and its biodegradation product, 4-nonylphenol (NP), in samples collected from the wastewater treatment system at the University Hospital (HUSM) of the Federal University of Santa Maria. The results showed a high concentration of NP9EO in all the collected samples (0.075 - 4.12 mg L(-1)) and an almost complete absence of NP. In addition, electrocoagulation (EC) of NP9EO was carried out in aqueous solution and in the HUSM effluent. A NP9EO removal rate of 95 % was achieved from the aqueous solution, following a pseudo-first-order kinetics. Through LC-MS measurements in aqueous solutions, it was possible to determine the formation of short-chain nonylphenol ethoxylate (NPEO), such as nonyl-phenoxy acetic acid (NP1EC), after 30 min of EC. In the case of the HUSM wastewater, the NP9EO removal was 89 %, and the chemical oxygen demand (COD) abatement was 26 %. A respirometric test was conducted to measure the increase of biodegradability during the EC and the aqueous samples were found to be less readily biodegradable before the 30-min period of electrocoagulation than after it had been completed.

Ciprofloxacin in hospital effluent: degradation by ozone and photoprocesses.

There are several papers in the literature that have recorded satisfactory results for the degradation of different pharmaceuticals in aqueous solutions by means of oxidation processes; however, only a few of them relied on real samples in carrying out their investigations. This study examines the results of the performance of photo-induced oxidation, heterogeneous photocatalysis, ozonation and peroxone in degrading the fluoroquinolone antimicrobial ciprofloxacin (CIP) in a hospital effluent. The real samples were collected from the treatment system of the University Hospital of Santa Maria (HUSM). Liquid chromatography with fluorescence detection (LC-FLD) was used to monitor the decrease of the CIP concentration. As expected, photo-induced oxidation was much slower than the other processes in bringing about total CIP degradation. Both heterogeneous photocatalysis and peroxone led to almost complete CIP degradation after 60 min treatment. Ozonation showed the best performance: total degradation after 30 min treatment. This was an unexpected result in view of the greater capacity of the other two processes to generate hydroxyl radicals. However, this finding supports a result in the literature that has tended to be overlooked. The by-products formed during the application of the processes were found to be very similar. Moreover, on the basis of the data obtained from the literature, there is some evidence to suggest that the by-products are derived from the oxidation of the piperazine group.

Photo-degradation of the antimicrobial ciprofloxacin at high pH: identification and biodegradability assessment of the primary by-products.

Photo-treatment for the removal of pharmaceuticals in effluents is a topic currently under discussion. In some countries effluents from hospitals are directly emitted into open ditches without any further treatment and with very little dilution. Under such circumstances photo-degradation in the environment can occur. However, photo-degradation does not necessarily end up with the complete mineralization of a chemical. Therefore, photo-product biodegradability and toxicity against environmental bacteria is of interest. Hospital effluents have often a pH around 9. Therefore, photo-oxidation (150W medium-pressure Hg-lamp, batch reactor) of ciprofloxacin (CIP) was studied at pH 9. The primary elimination of CIP was monitored and structures of photo-products were assessed by liquid chromatography ion trap mass spectrometry (LC-MS/MS). Five compounds were identified as probable products of photo-defluorination, -decarboxylation and loss of the piperazine moiety. These photo-products were not biodegradable in the Closed Bottle test - OECD 301D. They did not affect Vibrio fisheri in the applied concentrations.

Delta-aminolevulinate dehydratase (delta-ALA-D) activity in diabetes and hypothyroidism.

OBJECTIVES: This study analyzed the influence of type 2 diabetes mellitus and primary hypothyroidism on the activity of the delta-aminolevulinate dehydratase (delta-ALA-D) in human blood. DESIGN AND METHODS: Delta-ALA-D enzyme activity was determined in normal (healthy) people (n=29), compensated (DMC, n=11) and non-compensated diabetic patients (NDMC, n=23), and in patients with compensated (CH, n=19) and non-compensated primary hypothyroidism (NCH, n=10). The determination of lead, copper, zinc and magnesium was performed by graphite furnace atomic absorption spectrometry. RESULTS: This study shows that delta-ALA-D activity was decreased (P<0.05) in situations associated to hyperglycemia maintained for long periods (HbA1c high). Another finding of this study suggests that states of hypofunction of the thyroid gland, when non-compensated, increase the activity of delta-ALA-D (P<0.001). In addition, copper was elevated in HNC, zinc was diminished in DMC, HC and HNC, and magnesium was diminished in the HNC group. CONCLUSION: This result points out that there is a correlation among diabetes, hypothyroidism and delta-ALA-D activity.

Low temperature conversion of rice husks, eucalyptus sawdust and peach stones for the production of carbon-like adsorbent.

In this study, the feasibility of preparing effective adsorbents from unmitigated agroforestry wastes was investigated. Three different kinds of carbon-like materials were produced by low temperature pyrolysis (LTC, <500 degrees C) of the raw materials rice husks, eucalyptus sawdust and peach stones. The carbon-like materials were characterized by instrumental methods (SEM,X-RDS,BET,MAS-RMN,FTIR), physico-chemical adsorption (iodine-, methylene blue- and phenazone-number; acetic acid adsorption isotherm; textile dyes- and carbohydrate adsorption), and heat value determination. The produced materials, which showed appreciable adsorption capacity, can be considered as precursors for the production of active coal or even be used directly as well.

Photocatalytic degradation of brilliant red dye and textile wastewater.

The degradation of textile wastewater and brilliant red dye solutions in a coil photoreactor provided with recirculation, assisted by powdered TiO2 and medium-pressure mercury lamp irradiation, was investigated. Factorial design was used for the attainment of the best conditions for COD and color abatement. pH and TiO2 loading showed to be critical variables for the photocatalytic degradation process for both textile wastewater and aqueous reactive dye solutions (25 mg L(-1)). For both substrates, the optimized process conditions by factorial design were almost the same (pH 2-3, 444 mg TiO2 L(-1) loading, 5 L h(-1) recirculation flow-rate). A 41% COD abatement for textile wastewater was obtained with a 120 min treatment. For the Brilliant Red dye solutions, a 20 min treatment resulted in about 90% decolorization (517 nm, pH 5), as well as in a reduction of 66% of the integrated absorbance (200-600 nm, pH 5).

Influence of variables of the combined coagulation-Fenton-sedimentation process in the treatment of trifluraline effluent.

The effluent stream from the industrial production of the herbicide trifluraline (amination water) was submitted to a combined treatment of a physical-chemical process (coagulation) with an advanced oxidation process (Fenton). The recovering of the residual sludge was performed. The combined coagulation-Fenton-sedimentation process proved to be very suitable for wastewater color reduction (91.6%), promoting considerable abatement of the organic load (63.4% COD reduction). According to the fractionary factorial design, the main effects of pH (A) and Fenton sludge (B) variables were considered statistical fluctuations of the process (and not decisive), while the main effects of Fe(3+) (C), Fe(2+) (D) and H(2)O(2) (E), as well as the interactions between variables A and B, A and E, C and D and C and E were considered significant. The obtained results suggest that the combined process can be advantageous for the treatment of recalcitrant industrial effluents, such as the amination water from the trifluraline production.

Comparison of advanced processes on the oxidation of acid orange 7 dye.

The degradation of acid orange 7 dye (AO7) was studied using a 1 L semi-batch tank stirred glass reactor for performing three different photochemical processes (photoperoxidation, Fenton, photo-Fenton). A commercial low pressure lamp was used for irradiation of samples. The advancement of degradation was monitored by measurement of color reduction, UV-spectra, HPLC-UV and COD. The obtained results showed that the photo-Fenton treatment was the most effective for the degradation of AO7.