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1.
Sci Total Environ ; 934: 173260, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38761933

RESUMO

The LIFE SURFING Project was carried out at the Bailin Landfill in Sabiñánigo, Spain (2020-2022), applying Surfactant Enhanced Aquifer Remediation (SEAR) and In Situ Chemical Oxidation (S-ISCO) in a 60-meter test cell beneath the old landfill, to remediate a contaminated aquifer with dense non-aqueous phase liquid (DNAPL) from nearby lindane production. The project overcame traditional extraction limitations, successfully preventing groundwater pollution from reaching the river. In spring 2022, two SEAR interventions involved the injection of 9.3 m3 (SEAR-1) and 6 m3 (SEAR-2) of aqueous solutions containing 20 g/L of the non-ionic surfactant E-Mulse 3®, with bromide (around 150 mg/L) serving as a conservative tracer. 7.1 and 6.0 m3 were extracted in SEAR-1 and SEAR-2, respectively, recovered 60-70 % of the injected bromide and 30-40 % of the surfactant, confirming surfactant adsorption by the soil. Approximately 130 kg of DNAPL were removed, with over 90 % mobilized and 10 % solubilized. A surfactant-to-DNAPL recovery mass ratio of 2.6 was obtained, a successful value for a fractured aquifer. In September 2022, the S-ISCO phase entailed injecting 22 m3 of a solution containing persulfate (40 g/L), E-Mulse 3® (4 g/L), and NaOH (8.75 g/L) in pulses over 48 h, oxidizing around 20 kg of DNAPL and ensuring low toxicity levels after that. Preceding the SEAR and S-ISCO trials, 2020 and 2021 were dedicated to detailed groundwater flow characterizations, including hydrological and tracer studies. These preliminary investigations allowed the design of a barrier zone between 317 and 557 m from the test cell and the river, situated 900 m away. This zone, integrating alkali dosing, aeration, vapor extraction, and oxidant injection, effectively prevented the escape of fluids to the river. Neither surfactants nor contaminants were detected in river waters post-treatment. The absence of residual phase in test cell wells and reduction of chlorinated compound levels in groundwater were noticed till one year after S-ISCO.

2.
Sci Total Environ ; 926: 171847, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38527535

RESUMO

The uncontrolled disposal of the liquid lindane wastes have led to the formation of dense non-aqueous phase liquids (DNAPL), consisting of 28 chlorinated organic compounds (COCs), contaminating soil and groundwater. Surfactant-enhanced aquifer remediation is proposed as technology to treat these sites. However, the polluted emulsion generated must be manged on-site. In this work a two-step process is applied to treat emulsion composed of E-Mulse® 3 (4 g·L-1) as surfactant and a DNAPL (2 gCOCs·L-1). In the first, the COCs were selectively adsorbed in a granular activated carbon (GAC) column with Fe (II) previously adsorbed (10-20mg·g-1) onto the carbon surface, recovering an aqueous phase with surfactant for their reuse. In the second step, the spent GAC was regenerated with a 40 g·L-1 solution of hydrogen peroxide fed to the column at 2 mL·min-1 to promote the oxidation of the COCs adsorbed in the GAC. The kinetic and adsorption model in a multisolute (surfactant and DNAPL) system has been proposed. Five successive cycles of regeneration/adsorption have been successfully applied in the column process. About 50 % of the COCs were retained from the emulsion, and more than 70 % of the surfactant was recovered. The consumption of unproductive oxidants decreased with the number of regeneration cycles. The water effluent obtained after regeneration of GAC did not present chlorinated compounds desorbed and nontoxic by-products generated, such as short-chain acids.

3.
Environ Pollut ; 343: 123205, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38142033

RESUMO

The oxidation of hexachlorocyclohexane isomers in the aqueous phase (Milli-Q and groundwater) was studied using persulfate activated by ferrioxalate and solar light at circumneutral pH. The experiments were conducted in a solar simulator reactor with local radiation fluxes qw= 1.12·10-7 E cm-2s-1 and in compound parabolic collectors with solar light (qw≈10-7 E cm-2s-1) for 390 min. The effect of activator dosage (18-125 µM ferrioxalate) and persulfate concentration (520-2600 µM) on hexachlorocyclohexane conversion and oxalate and oxidant consumption was analyzed. Conversion of about 95% of ß isomer was achieved at 390 min using 1300 µM of initial persulfate and 63 µM of Fe3+ concentration despite this ß isomer being the most recalcitrant to oxidation (XHexachlorocyclohexanes=0.98). Dechlorination above 80% was achieved under these conditions, analyzing the chlorides released into the water. The influence of chloride and bicarbonate on hexachlorocyclohexanes degradation was analyzed in milli-Q water and in groundwater. Hexachlorocyclohexane conversion at 390 min decreases from 98% to 83, 75 and 65% in the presence of chloride, bicarbonate or groundwater, respectively. Results obtained with compound parabolic collectors and solar light using 2600 µM Na2S2O8 and 63 µM Fe for removing hexachlorocyclohexanes agreed with those from the solar simulator reactor, supporting using solar light to activate persulfate for sustainable abatement of persistent organic pollutants in aqueous matrixes.


Assuntos
Água Subterrânea , Praguicidas , Poluentes Químicos da Água , Hexaclorocicloexano , Bicarbonatos , Cloretos , Oxalatos/química , Água Subterrânea/química , Água , Oxirredução , Poluentes Químicos da Água/análise , Sulfatos/química
4.
Chemosphere ; 341: 140047, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37660800

RESUMO

A common strategy for removing highly toxic organic compounds, such as chlorinated organic compounds, is their adsorption on granular activated carbon. Spent granular activated carbon results in a toxic residue to manage; therefore, the regeneration and reuse of granular activated carbon on the site would be advisable. This work studies the regeneration of a granular activated carbon saturated in 1,2,4-trichlorobenzene, chosen as the model chlorinated organic compounds, by heterogeneous Fenton, where iron was previously immobilised on the granular activated carbon surface. This methodology avoids the addition of iron to the aqueous phase at concentrations above the allowable limits and the need for acidification. Three successive cycles of adsorption-regeneration were carried out batchwise (5 gGAC·L-1) with a granular activated carbon saturated with 300 mg124-TCB·gGAC-1. The recovery of the adsorption capacity after regeneration was studied with H2O2 (166 mM, 1.5 the stoichiometric dosage), at different concentrations adsorbed with iron adsorbed concentrations (0-12 mgFe·gGAC-1) and temperatures (20-80 °C). Stable recovery of the adsorption capacity values of 65% were obtained at 180 min with 12 mgFe·gGAC-1 and 60 °C. The porosity and surface chemistry of the adsorbent remained very similar after different adsorption-regeneration cycles without iron leaching into the aqueous phase. The oxidant consumption was close to the stoichiometric value for the mineralization of 1,2,4-trichlorobenzene, with a low unproductive consumption of H2O2 with granular activated carbon. In addition, no aromatic or chlorinated by-products were detected in the aqueous solution obtained in the regeneration process. The negligible toxicity of the aqueous phase with the Microtox bioassay confirmed the absence of toxic oxidation by-products.


Assuntos
Peróxido de Hidrogênio , Poluentes Químicos da Água , Peróxido de Hidrogênio/química , Carvão Vegetal , Temperatura , Ferro/química , Adsorção , Poluentes Químicos da Água/química
5.
Eur J Hum Genet ; 31(12): 1393-1397, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37699995

RESUMO

Important advances in genetics research have been made in recent years. Such advances have facilitated the availability of huge amounts of genetic information that could potentially be reused beyond the original purpose for which such information was obtained. Any such reuse must meet certain ethical criteria to ensure that the dignity, integrity, and autonomy of the individual from whom that information was obtained are protected. The aim of this paper is to reflect on these criteria through a critical analysis of the literature. To guarantee these values, ethical criteria need to be established in several respects. For instance, the question must be posed whether the information requires special attention and protection (so-called genetic exceptionalism). Another aspect to bear in mind is the most appropriate type of consent to be given by the person involved, on the one hand favouring research and the reuse of genetic information while on the other protecting the autonomy of that person. Finally, there is a need to determine what protection such reuse should have in order to avoid detrimental consequences and protect the rights of the individual. The main conclusions are that genetic information requires special care and protection (genetic exceptionalism) and that broad consent is the most practical and trustworthy type of consent for the reuse of genetic information.


Assuntos
Privacidade Genética , Testes Genéticos , Consentimento Livre e Esclarecido , Humanos
7.
Ind Eng Chem Res ; 62(7): 3282-3293, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36853619

RESUMO

Surfactant-enhanced aquifer remediation is commonly applied in polluted sites with dense non-aqueous phase liquids (DNAPLs). This technique transfers the contamination from subsoil to an extracted emulsion, which requires further treatment. This work investigated the treatment of a complex emulsion composed of a nonionic surfactant and real DNAPL formed of chlorinated organic compounds (COCs) and generated as a lindane production waste by air stripping under alkaline conditions. The influence of the surfactant (1.5-15 g·L-1), COC concentrations (2.3-46.9 mmol·L-1), and temperature (30-60 °C) on the COC volatilization was studied and modeled in terms of an apparent constant of Henry at pH > 12. In addition, the surfactant stability was studied as a function of temperature (20-60 °C) and surfactant (2-10 g·L-1), COC (0-70.3 mmol·L-1), and NaOH (0-4 g·L-1) concentrations. A kinetic model was successfully proposed to explain the loss of surfactant capacity (SCL). The results showed that alkali and temperature caused the SCL by hydrolysis of the surfactant molecule. The increasing surfactant concentration decreased the COC volatility, whereas the temperature improved the COC volatilization. Finally, the volatilization of COCs in alkaline emulsions by air stripping (3 L·h-1) was performed to evaluate the treatment of an emulsion composed of the COCs (17.6 mmol·kg-1) and surfactant (3.5 and 7 g·L-1). The air stripping was successfully applied to remove COCs (>90%), reaching an SCL of 80% at 60 °C after 8 h. Volatilization can remove COCs from emulsions and break them, enhancing their further disposal.

8.
Molecules ; 27(24)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36558105

RESUMO

The discharge of lindane wastes in unlined landfills causes groundwater and soil pollution worldwide. The liquid waste generated (a mixture of 28 chlorinated organic compounds, COCs) constitutes a dense non-aqueous phase liquid (DNAPL) that is highly persistent. Although in situ chemical oxidation (ISCO) is effective for degrading organic pollutants, the low COCs solubility requires high reaction times. Simultaneous injection of surfactants and oxidants (S-ISCO) is a promising technology to solve the limitation of ISCO treatment. The current work studies the remediation of highly polluted soil (COCs = 3682 mg/kg) obtained at the Sardas landfill (Sabiñáñigo, Spain) by ISCO and S-ISCO treatments. Special attention is paid to acute soil toxicity before and after the soil treatment. Microtox®, modified Basic Solid-Phase Test (mBSPT) and adapted Organic Solvent Sample Solubilization Test (aOSSST) were used for this scope. Persulfate (PS, 210 mM) activated by alkali (NaOH, 210 mM) was used in both ISCO and S-ISCO runs. A non-ionic and biodegradable surfactant selected in previous work, Emulse®3 (E3, 5, and 10 g/L), was applied in S-ISCO experiments. Runs were performed in soil columns filled with 50 g of polluted soil, with eight pore volumes (Pvs) of the reagents injected and 96 h between successive Pv injections. The total treatment time was 32 days. The results were compared with those corresponding without surfactant (ISCO). After remediation treatments, soils were water-washed, simulating the conditions of groundwater flux in the subsoil. The treatments applied highly reduced soil toxicity (final soil toxicity equivalent to that obtained for non-contaminated soil, mBSPT) and organic extract toxicity (reduction > 95%, aOSSST). Surfactant application did not cause an increase in the toxicity of the treated soil, highlighting its suitability for full-scale applications.


Assuntos
Água Subterrânea , Surfactantes Pulmonares , Poluentes do Solo , Poluentes Químicos da Água , Hexaclorocicloexano/toxicidade , Tensoativos/toxicidade , Poluição Ambiental , Oxirredução , Poluentes Químicos da Água/química , Solo/química , Poluentes do Solo/toxicidade , Poluentes do Solo/química , Água Subterrânea/química
9.
Ind Eng Chem Res ; 61(27): 9611-9620, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35855725

RESUMO

Chlorinated organic compounds (COCs) are persistent organic pollutants often found in groundwater near industrial sites or in industrial wastewaters. Adsorption into activated carbon is a common strategy to remediate these waters, but spent activated carbon results in a toxic residue to manage. To avoid the transport of the chlorinated compounds out of the site, the in-situ regeneration of the spent activated carbon can be considered for reuse to implement a circular economy. In this work, the regeneration of a commercial granular activated carbon (GAC) has been carried out using thermally activated sodium persulfate (TAP). GAC was previously saturated in 1,2,4-trichlorobenzene (124-TCB) as the model compound. The initial adsorption value was 350 mg124-TCB·gGAC -1. First, the nonproductive consumption of sodium persulfate was studied at different temperatures using nonsaturated GAC. Then, the regeneration of the saturated GAC (5 g) was studied by an aqueous solution (166 mM) of TAP (1 L) at a temperature range from 20 to 80 °C. The possible recovery of the adsorption capacity was studied after 3 h of treatment in three successive adsorption-regeneration cycles at the selected temperature (60 °C). The physicochemical changes of the GAC were also investigated before and after the regeneration treatments. The results evidence the significant deposition of sulfate on the GAC after each treatment of regeneration, which avoids the recovery of the initial adsorption capacity. Therefore, each regeneration cycle was necessarily followed by a washing step at 60 °C to remove this sulfate. After that, the regeneration treatment achieved a stable and high recovery of the initial adsorption capacity of about 48.2%.

10.
Artigo em Inglês | MEDLINE | ID: mdl-35742796

RESUMO

Surfactant enhanced aquifer remediation is a common treatment to remediate polluted sites with the inconvenience that the effluent generated must be treated. In this work, a complex mixture of chlorobenzene and dichlorobenzenes in a non-ionic surfactant emulsion has been carried out by volatilization. Since this techhnique is strongly affected by the presence of the surfactant, modifying the vapour pressure, Pv0, and activity coefficient, γ, a correlation between Pvj0γj and surfactant concentration and temperature was proposed for each compound, employing the Surface Response Methodology (RSM). Volatilization experiments were carried out at different temperatures and gas flow rates. A good agreement between experimental and predicted remaining SVCOCs during the air stripping process was obtained, validating the thermodynamic parameters obtained with RSM. Regarding the results of volatilization, at 60 °C 80% of SVCOCs were removed after 6 h, and the surfactant capacity was almost completely recovered so the solution can be recycled in soil flushing.

11.
J Environ Manage ; 306: 114475, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35033888

RESUMO

Sites polluted by dense non-aqueous phases (DNAPLs) constitute an environmental concern. In situ chemical oxidation (ISCO) application is limited since oxidation often occurs in the aqueous phase and contaminants are usually hydrophobic. In this work, ISCO enhanced by the surfactant addition (S-ISCO) was studied for a complex liquid mixture of chlorinated organic compounds (COCs) using persulfate (PS) activated by alkali (PSA) as oxidant and Emulse-3® as a commercial non-ionic surfactant. The reaction between E3 and PSA was investigated in the absence and presence of solubilized COCs in the following concentration ranges: COCs 1.2-50 mM, PS 84-336 mM, NaOH:PS molar ratio of 2, and surfactant concentration 1-10 g·L-1. In the experiments carried out in the absence of COCs, the unproductive consumption of PS was studied. The higher the surfactant concentration, the lower the ratio PS consumed to the initial surfactant concentration due to more complex micelle structures hindering the oxidation of surfactant molecules. This hindering effect was also noticed in the oxidation of solubilized COCs. The reduction of chlorobenzenes by PSA was negligible at surfactant concentrations above 2.5 g·L-1, independently of the COCs concentration solubilized. Instead, a surfactant concentration of about 1 and PS concentration of 168 mM yielded a significant decrease in the time required to abate a mass of DNAPL, compared with an ISCO process, with a bearable increase in the unproductive consumption of PS.


Assuntos
Tensoativos , Poluentes Químicos da Água , Álcalis , Clorobenzenos , Compostos Orgânicos , Oxirredução , Sulfatos , Poluentes Químicos da Água/análise
12.
BMC Health Serv Res ; 22(1): 60, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-35022061

RESUMO

OBJECTIVE: To describe in detail an innovative program based on telemedicine for semi-automated prioritization of referrals from Primary Care (PC) to Rheumatology, for reproducibility purposes, and to present the results of the implementation study. METHODS: The context and situation were carefully analyzed, paying attention to all processes in place, referral numbers, waiting times, and number of complementary tests prior to discharge from Rheumatology. The composition of the team, aims, users, scope, and implementation phases were defined. Eight process indicators were established and measured before and 32 months after the program implementation. RESULTS: The program, which includes IT circuits, algorithms based on response to specific guideline-based checklists, e-consultation, and appointments based on priority, was fully implemented in our health area after a pilot study in two PC centers. After implementation, 6185 rheumatology referrals showed an e-consultation response delay of 8.95 days, and to first face-to-face visit (after e-consultation) of 12.6 (previous delay before program implementation was 83.1 days). Resolution by e-consultation reached 20% (1195 patients did not need seeing the rheumatologist to have the problem solved), and 1369 patients (32%) were discharged after the first visit. The overall resolution rate was 44.0% (2564 discharges/5830 e-consultations). From a random sample of 100 visits, only 10% of patients needed additional complementary tests to make a diagnosis and decision by Rheumatology (20.9% decrease from previous period). CONCLUSION: A careful analysis of the situation and processes, with implementation of simple IT circuits, allows for the improvement of the efficiency and resolution of problems in Rheumatology.


Assuntos
Reumatologia , Comunicação , Humanos , Projetos Piloto , Atenção Primária à Saúde , Encaminhamento e Consulta , Reprodutibilidade dos Testes , Listas de Espera
14.
Clin Genet ; 99(1): 93-98, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32779199

RESUMO

Newborn screening is a public health strategy used to identify certain diseases in the first days of life and, therefore, facilitate early treatment before the onset of symptoms. The decision of which diseases should be included in a screening goes beyond the medical perspective, including reasons for public health and health economics. There are a number of characteristics to include a disease in the screening, such as that the disorder must be a significant health problem, the natural history of the disease must be well known, a feasible and accurate test must be available, there must be a treatment that is most effective when applied before the onset of clinical symptoms and a health system must be in place that is capable of performing the procedure and subsequent monitoring. Currently, newborn screening programs are currently based on the use of biochemical markers that detect metabolites, hormones or proteins, but recently, the availability of new technology has allowed the possibility of a genetic screening. In addition to technical problems, the possibility of neonatal screening also presents a number of ethical problems. We identified and discussed six areas of particular concern: type of illness, overdiagnosis or overtreatment, information management and informed consent, data confidentiality and protection, justice and legal regulation.


Assuntos
Testes Genéticos/ética , Triagem Neonatal/ética , Saúde Pública/ética , Humanos , Recém-Nascido , Consentimento Livre e Esclarecido/ética
15.
Sci Total Environ ; 751: 141782, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32882562

RESUMO

Surfactant Enhanced In-Situ Chemical Oxidation (S-ISCO) is an emerging technology in the remediation of sites with residual Dense Non-Aqueous Phase Liquids (DNAPLs), a ubiquitous problem in the environment and a challenge to solve. In this work, three nonionic surfactants: E-Mulse3® (E3), Tween80 (T80), and a mixture of Tween80-Span80 (TS80), and an anionic surfactant: sodium dodecyl sulfate (SDS), combined with persulfate activated by alkali (PSA) as oxidant have been investigated to remove the DNAPL generated as liquid waste in lindane production, which is composed of 28 chlorinated organic compounds (COCs). Because the compatibility between surfactants and oxidants is a key aspect in the S-ISCO effectiveness the unproductive consumption of PS by surfactants was investigated in batch (up to 864 h) varying the initial concentration of PS (84-42 mmol·L-1) and surfactants (0-12 g·L-1) and the NaOH:PS molar ratio (1 and 2). The solubilization capacity of a partially oxidized surfactant was analyzed by estimating its Equivalent Surfactant Capacity, ESC, (as mmolCOCs dissolvedgsurf-1) and comparing it to the expected value for an unoxidized surfactant, ESCo. Finally, the abatement of DNAPL with simultaneous addition of surfactant and PSA was studied. At the conditions used, a negligible unproductive consumption of PS was found by SDS; meanwhile, PS consumption at 360 h ranged between 70 and 80% using the nonionic surfactants. The highest ratios of ESC/ESCo were found with SDS and E3 and these surfactants were chosen for the S-ISCO treatment. When oxidant and surfactant were simultaneously applied for DNAPL abatement the COC conversion was more than three times higher with E3 (0.6 at 360 h) than SDS. Moreover, it was obtained that the time needed for the removal of a mass of DNAPL by PSA in the absence of surfactants was notably higher than the time required when a suitable surfactant was added.

16.
Artigo em Inglês | MEDLINE | ID: mdl-32585799

RESUMO

Application of surfactants in the remediation of polluted sites with dense nonaqueous phase liquid (DNAPL) still requires knowledge of partitioning between surfactants and pollutants in the organic and aqueous phases and the time necessary to reach this balance. Two real DNAPLs, generated as wastes in the lindane production and taken from the polluted sites from Sabiñanigo (Spain), were used for investigating the solubilization of 28 chlorinated organic compounds (COCs) applying aqueous surfactant solutions of three nonionic surfactants (E-Mulse® 3 (E3), Tween®80 (T80), and a mixture of Tween®80-Span®80 (TS80)) and an anionic surfactant (sodium dodecyl sulfate (SDS)). The initial concentrations of surfactants were tested within the range of 3-17 g·L-1. The pH was also modified from 7 to >12. The uptake of nonionic surfactants into the organic phase was higher than the anionic surfactants. Solubilization of COCs with the nonionic surfactants showed similar molar solubilization ratios (MSR = 4.33 mmolCOCs·g-1surf), higher than SDS (MSR = 0.70 mmolCOCs·g-1SDS). Furthermore, under strong alkaline conditions, the MSR value of the nonionic surfactants was unchanged, and the MSR of SDS value increased (MSR = 1.32 mmolCOCs·g-1SDS). The nonionic surfactants did not produce preferential solubilization of COCs; meanwhile, SDS preferentially dissolved the more polar compounds in DNAPL. The time required to reach phase equilibrium was between 24 and 48 h, and this contact time should be assured to optimize the effect of the surfactant injected on COC solubilization.


Assuntos
Hexaclorocicloexano , Tensoativos , Concentração de Íons de Hidrogênio , Dodecilsulfato de Sódio , Solubilidade
17.
J Environ Manage ; 261: 110240, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32148309

RESUMO

Chlorinated pesticides were extensively produced in the XX century, generating high amounts of toxic wastes often dumped in the surroundings of the production sites, resulting in hot points of soil and groundwater pollution worldwide. This is the case of Bailín landfill, located in Sabiñánigo (Spain), where groundwater is highly polluted with chlorobenzenes (mono, di, tri and tetra) and hexachlorocyclohexanes. This study addresses the abatement of chlorinated organic compounds (COCs) present in the groundwater coming from the Bailín landfill by thermally activated persulfate, PS (TAP). The influence of temperature (30-50 °C) and oxidant concentration (2-40 g L-1) on the efficiency of COCs (initial concentration of COCs = 57.53 mg L-1, determined by the solubility of the pollutants in water) degradation has been investigated. Raising the reaction temperature and PS concentration the degradation of COCs significantly accelerates, as a result of higher production of sulfate radicals. The thermal activation of PS implies side reactions, involving the unproductive decomposition of this oxidant. The activation energy calculated for this reaction (128.48 kJ mol-1) reveals that is slightly more favored by temperature than the oxidation of COCs by sulfate radicals (102.4-115.72 kJ mol-1). At the selected operating conditions (PS = 10 g L-1, 40 °C), the almost complete conversion of COCs and a dechlorination and mineralization degree above 80% were obtained at 168 h reaction time. A kinetic model, able to adequately predict the experimental concentration of COCs when operating at different temperatures and initial concentration of PS has been proposed.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Compostos Orgânicos , Oxirredução , Sulfatos , Instalações de Eliminação de Resíduos
18.
J Environ Manage ; 255: 109926, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32063307

RESUMO

Treatment of polluted wastewaters from industrial activities has become a source of major concern for the environment. In this work, real wastewater from a physico-chemical (WWFQ) treatment was tested through different oxidation technologies: Fenton and Fenton-like reagent and persulfate activated by NaOH and Fe(II). Oxidation reactions with Fenton's reagent were carried out in a 0.25 L batch reactor at 25 °C by adding either Fe(II) or Fe(III) and H2O2 to an aqueous solution of wastewater, whose pH was previously adjusted to 2 or 3. Iron concentration ranging from 25 to 100 mg/L and peroxide concentration from 2500 to 10000 mg/L were used. The total organic carbon slightly decreased when WWFQ was treated. Moreover, better results were obtained when Fe(II) was used than Fe(III). Both iron concentration and oxidant dosage had a positive influence on the chemical oxygen demand (COD) removal, until an asymptotic value of 30% was obtained. Oxidation of pollutants contained in WWFQ was studied with persulfate (18.4-294 mM) activated with NaOH and Fe(II) (36.8-588 mM). Again, a positive influence of both persulfate and NaOH was observed, although a similar asymptotic COD value was observed. This parallelism between both technologies confirms recalcitrant compounds were obtained.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Compostos Férricos , Compostos Ferrosos , Peróxido de Hidrogênio , Oxirredução , Hidróxido de Sódio , Eliminação de Resíduos Líquidos
19.
Farm Hosp ; 45(1): 3-9, 2020 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-33443471

RESUMO

OBJECTIVE: The objective of this study was to assess the results of applying  Lean Methodology in the design of a standardized medication storage model in  hospitalization departments. METHOD: Descriptive and retrospective study conducted between September 2017 and January 2019 in a tertiary level hospital. The Pharmacy Service led the creation of a multidisciplinary team. Lean Methodology was used to establish the components and organization and  identification criteria that made up the standardized medication storage model.  The stocks of each hospitalization department were reviewed and quantified, the final amount of stock needed was agreed with the supervisor of each department, and the economic impact of the implementation of the  standardized medication model was assessed. A questionnaire was designed and sent to nursing staff to determine their level of satisfaction with the new model. RESULTS: The standardized medication storage model was scaled up to 20  nursing departments, leading to an overall reduction of 56.72% in the number of pharmaceutical dosage forms available (5,688 vs 2,462). The number of high-risk drugs was reduced by 40.73% (631 vs 374). This elimination of wastage  achieved a saving of €25,357.98. A total of 58 nurses returned the  questionnaires (20.70% of the total): 22.40% worked a fixed shift and 77.60%  worked a rotating shift. The mean score on overall satisfaction was 5.79 ± 3.61  (scores ranged from 1 to 10). CONCLUSIONS: The application of Lean Methodology is very useful for the  management of medication stocks in hospitalization departments. The implementation of a standardized medication storage model leads to  economic savings and a marked reduction in the number of active ingredients and high-risk medications. The nursing staff were satisfied with the  implementation of the model, suggesting that we should continue to pursue this effective line of action.


Objetivo: El objetivo del estudio es evaluar los resultados de la aplicación de la  metodología Lean en el diseño de un modelo estandarizado de almacenaje de  medicación en las unidades de hospitalización. Método: Estudio descriptivo y  retrospectivo desarrollado entre septiembre de  2017 y enero de 2019 en un  hospital de tercer nivel. Se creó un  equipo multidisciplinar liderado por el  Servicio de Farmacia. Se empleó la  metodología Lean para establecer los  elementos y criterios de organización e identificación que conformaron el modelo estandarizado de almacenaje de  medicación. Se revisaron y cuantificaron los stocks de cada unidad de hospitalización, se consensuó la medicación con la supervisora de cada unidad y se estimó el impacto económico de la implantación del modelo estandarizado. Se diseñó y envió una encuesta para evaluar la  satisfacción de enfermería con el nuevo modelo.Resultados: El modelo estandarizado de almacenaje se aplicó en 20 unidades de enfermería y supuso una reducción global del 56,72% en el número  de presentaciones de principios activos disponibles (5.688 versus 2.462). Se disminuyó el número de presentaciones de principios activos  de medicamentos de alto riesgo en un 40,73% (631 versus 374). La eliminación de este despilfarro supuso un ahorro económico de 25.357,98 €. Se recibieron 58 respuestas a la encuesta de satisfacción del personal de enfermería (20,70%  del total de encuestas enviadas), de las que un 22,40% correspondieron al turno fijo y 77,60% al turno rotativo. La media de la satisfacción global (valorada  entre 1 y 10) fue de 5,79 ± 3,61.Conclusiones: La aplicación de la metodología Lean es útil para la gestión de  stocks de medicación de las unidades de hospitalización. La implantación del  modelo estandarizado de almacenaje conlleva un ahorro económico y una  reducción del número de presentaciones de principios activos y de  medicamentos de alto riesgo. El personal de enfermería está conforme con la  implantación del modelo, lo que nos plantea seguir en esta línea de mejora.


Assuntos
Assistência Farmacêutica , Hospitalização , Humanos , Estudos Retrospectivos , Inquéritos e Questionários , Centros de Atenção Terciária
20.
Chemosphere ; 239: 124798, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31527006

RESUMO

Hexachlorocyclohexane (HCH) and mainly the γ-HCH isomer, namely lindane, were extensively produced and used as pesticides. Huge amounts of wastes, solids and liquids, were disposed of in the surroundings of the production sites. The liquid residuum was a complex mixture of chlorinated organic compounds, COCs, from chlorobenzene to heptachlorocyclohexane. This Dense Non-Aqueous Phase Liquid, DNAPL, migrated by density through the subsurface to greater depths, being trapped or adsorbed into the soil in this movement posing a significant risk to the groundwater. Knowledge of the partitioning in water of COCs in DNAPL is a key issue to determine its fate in the environment. However, there are no data in literature for the partitioning and/or solubility of many of the COCs in this DNAPL, such as pentachlorocyclohexene, hexachlorocyclohexene and heptachlorocyclohexane despite them constitute about 13-30% of the mole fraction of the DNAPLs. In this work, the partitioning to water of COCs in free and those adsorbed onto soil has been studied. In addition, measured and predicted aqueous concentrations of each COC in the DNAPL mixture have been compared. To do this, the solubility of a compound that is a solid crystal when pure at P = 298 K and P = 1 atm has been evaluated considering the approach of sub-cooled liquid state of solid organochlorines. Samples were obtained at Sabiñanigo landfills and soils used had several grain sizes. Transformation in alkaline media of COCs had a positive environmental impact.


Assuntos
Hexaclorocicloexano , Hidrocarbonetos Clorados/química , Poluentes do Solo/química , Halogenação , Hexaclorocicloexano/análogos & derivados , Hexaclorocicloexano/química , Solubilidade , Espanha , Instalações de Eliminação de Resíduos , Água/química , Poluentes Químicos da Água/química
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