Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.887
Filtrar
1.
Rev Gaucha Enferm ; 42(spe): e20200146, 2021.
Artigo em Inglês, Português | MEDLINE | ID: mdl-33787720

RESUMO

OBJECTIVE: To evaluate the protocols on decontamination/reuse of N95 masks available in the literature in times of the Covid-19 pandemic. METHOD: Integrative literature review, in the period from 2010 to 2020, on the databases MEDLINE/PubMed, Science Direct, Cochrane, SAGE journals, Web of Science, Scopus, Embase and Wiley, with the descriptors Masks AND Respiratory protective devices; Mask OR N95 AND Covid-19; N95 AND Respirators; Decontamination AND N95 AND Coronavirus; Facemask OR Pandemic. RESULTS: Twelve studies were included, of which 3 (30.0%) used ultraviolet germicidal irradiation and indicated mask deterioration between 2 and 10 cycles, 4 (40.0%) used hydrogen peroxide vapor, and seal loss varied from 5 to 20 cycles, 4 (33.3%) evaluated the structural integrity of the N95 mask through visual inspection and 6 (54.4%), its filtration efficiency. CONCLUSION: Reuse strategies to overcome a shortage of devices in the face of the pandemic challenge the current concept for good practices in health-product processing.


Assuntos
/epidemiologia , Descontaminação/métodos , Reutilização de Equipamento , Pandemias , Anti-Infecciosos Locais , Desinfetantes , Desinfecção/métodos , Óxido de Etileno , Filtração/instrumentação , Humanos , Peróxido de Hidrogênio , Raios Ultravioleta
2.
Emerg Infect Dis ; 27(4): 1229-1231, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33755002

RESUMO

Severe acute respiratory syndrome coronavirus 2 can persist on surfaces, suggesting possible surface-mediated transmission of this pathogen. We found that fomites might be a substantial source of transmission risk, particularly in schools and child daycares. Combining surface cleaning and decontamination with mask wearing can help mitigate this risk.


Assuntos
Transmissão de Doença Infecciosa/prevenção & controle , Fômites/virologia , Controle de Infecções , /isolamento & purificação , Idoso , Número Básico de Reprodução , /prevenção & controle , /virologia , Criança , Creches/normas , Descontaminação/métodos , Contaminação de Equipamentos/prevenção & controle , Desinfecção das Mãos/métodos , Humanos , Controle de Infecções/instrumentação , Controle de Infecções/métodos , Máscaras , Casas de Saúde/normas , Instituições Acadêmicas/normas , Estados Unidos/epidemiologia
3.
PLoS One ; 16(3): e0248487, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33735216

RESUMO

A gas-phase Advanced Oxidation Process (gAOP) was evaluated for decontaminating N95 and surgical masks. The continuous process was based on the generation of hydroxyl-radicals via the UV-C (254 nm) photo-degradation of hydrogen peroxide and ozone. The decontamination efficacy of the gAOP was dependent on the orientation of the N95 mask passing through the gAOP unit with those positioned horizontally enabling greater exposure to hydroxyl-radicals compared to when arranged vertically. The lethality of gAOP was independent of the applied hydrogen peroxide concentration (2-6% v/v) but was significantly (P<0.05) higher when H2O2 was introduced into the unit at 40 ml/min compared to 20 ml/min. A suitable treatment for N95 masks was identified as 3% v/v hydrogen peroxide delivered into the gAOP reactor at 40 ml/min with continuous introduction of ozone gas and a UV-C dose of 113 mJ/cm2 (30 s processing time). The treatment supported >6 log CFU decrease in Geobacillus stearothermophilus endospores, > 8 log reduction of human coronavirus 229E, and no detection of Escherichia coli K12 on the interior and exterior of masks. There was no negative effect on the N95 mask fitting or particulate efficacy after 20 passes through the gAOP system. No visual changes or hydrogen peroxide residues were detected (<1 ppm) in gAOP treated masks. The optimized gAOP treatment could also support >6 log CFU reduction of endospores inoculated on the interior or exterior of surgical masks. G. stearothermophilus Apex spore strips could be applied as a biological indicator to verify the performance of gAOP treatment. Also, a chemical indicator based on the oxidative polymerization of pyrrole was found suitable for reporting the generation of hydroxyl-radicals. In conclusion, gAOP is a verifiable treatment that can be applied to decontaminate N95 and surgical masks without any negative effects on functionality.


Assuntos
Descontaminação/métodos , Máscaras/virologia , Gases/química , Humanos , Peróxido de Hidrogênio/química , Radical Hidroxila/química , Oxirredução , Ozônio/química , Fotólise
6.
Int J Food Microbiol ; 341: 109068, 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33498009

RESUMO

Raw vegetables are a key food for a healthy diet, but their increased consumption brings a higher risk for foodborne disease. Contamination of salad greens with Shiga toxin-producing Escherichia coli (STEC) O157:H7 has caused severe disease and important economic losses almost yearly in the United States over the last 10 years. To curb the risk of infections from contaminated produce, approaches based on bacterial virus - commonly known as bacteriophage or phage - have recently started to draw interest among other antimicrobial strategies. Phages enter bacterial cells to reproduce and cause cellular lysis to release their phage progeny at the end of their infection cycle. This lytic effect is caused by lysins, phage-encoded enzymes that have evolved to degrade the bacterial cell wall resulting in hypotonic lysis. When applied externally in their purified form, such enzymes are able to kill sensitive bacteria on contact in a similar way. Their unique bactericidal properties have made lysins effective antimicrobial agents in a variety of applications, from treating multidrug-resistant infections in humans to controlling bacterial contamination in several areas, including microbiological food safety. Here we describe a novel lysin, namely PlyEc2, with potent bactericidal activity against key gram-negative pathogens including E. coli, Salmonella, Shigella, Acinetobacter and Pseudomonas. PlyEc2 displayed high bactericidal activity against STEC to a concentration of 12.5 µg/ml under different pH conditions. This lysin was also able to reduce the bacterial titer of several pathogenic strains in vitro by more than 5 logarithmic units, resulting in complete sterilization. Importantly, PlyEc2 proved to be a powerful produce decontamination agent in its ability to clear 99.7% of contaminating STEC O157:H7 in our Romaine lettuce leaf model. PlyEc2 was also able to eradicate 99.8% of the bacteria contaminating the washing solution, drastically reducing the risk of cross-contamination during the washing process. A sensory evaluation panel found that treatment with PlyEc2 did not alter the visual and tactile quality of lettuce leaves compared to the untreated leaves. Our study is the first to describe a highly effective lysin treatment to control gram-negative pathogenic contamination on fresh lettuce without the addition of membrane destabilizing agents.


Assuntos
Antibacterianos/farmacologia , Bacteriófagos/enzimologia , Escherichia coli O157/efeitos dos fármacos , Doenças Transmitidas por Alimentos/prevenção & controle , Alface/microbiologia , Bacteriófagos/metabolismo , Contagem de Colônia Microbiana , Descontaminação/métodos , Contaminação de Alimentos/análise , Microbiologia de Alimentos/métodos , Inocuidade dos Alimentos/métodos , Doenças Transmitidas por Alimentos/microbiologia , Humanos , Alimentos Crus/microbiologia
7.
Healthc Q ; 23(4): 35-38, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33475490

RESUMO

With the global outbreak of the COVID-19 pandemic, hospitals in Canada and around the world have been forced to consider conservation strategies to ensure continued availability of personal protective equipment (PPE) for healthcare providers. To mitigate critical PPE shortages, Sinai Health System (Sinai Health), a large academic healthcare institution in Canada, has developed and operationalized a standard operating procedure for the collection, decontamination and reuse of N95 respirators and other single-use PPE using a vaporized hydrogen peroxide decontamination method. Sinai Health has incorporated stringent quality assurance steps to ensure that the N95 respirators are successfully decontaminated without deformation and are safe to use.


Assuntos
Descontaminação/métodos , Contaminação de Equipamentos/prevenção & controle , Reutilização de Equipamento , Equipamentos e Provisões Hospitalares , /prevenção & controle , Infecção Hospitalar/prevenção & controle , Reutilização de Equipamento/normas , Equipamentos e Provisões Hospitalares/efeitos adversos , Equipamentos e Provisões Hospitalares/normas , Equipamentos e Provisões Hospitalares/virologia , Humanos , /normas , /virologia
8.
Int J Hyg Environ Health ; 232: 113690, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33434878

RESUMO

Countries with abundant solar radiation have the potential to invest in simple technologies for deactivation of many bacteria and viruses in medical solid waste. In addition to the traditional Infection and Prevention Control (IPC) measures, these simple technologies contribute to better protection of health care workers in countries with compromised solid management schemes. Monitoring of temperature, relative humidity and ultraviolet inside containers soundly designed to collect disposal infectious waste illustrated to deactivate several viruses and bacteria. Casanova et al., 2010, used some surrogate viruses to overcome the challenges of working with SARS-CoV, concluded that by temperature above 40 °C most of viruses become below levels of detection after 90 min. Here we are proposing a model of a simple transparent container almost 200 L in volume that allow solar energy to be accumulated inside. In summer conditions in the testing site, temperature inside the container reached above 50 °C when the ambient air temperature was around 30 °C. The container was built using epoxy glass to guarantee maximum heat penetration. Actual temperature measurement inside the container was measured in real time against ambient air temperature. We present a mathematical model for predication of maximum temperature at different positions inside the container and their relation to different ambient air temperature scenarios. The mathematical formulas used are based on the conservation laws and a good agreement of a full month of field measurements were obtained. Even in winter conditions in many of developing countries air temperature can maintain levels above 20 °C, which will produce temperature around 30 °C and viruses can reach levels below detection limit in maximum 3 h.


Assuntos
Descontaminação/métodos , Resíduos de Serviços de Saúde , Resíduos Sólidos , Luz Solar , Gerenciamento de Resíduos/métodos , Países em Desenvolvimento , Umidade , Modelos Teóricos , Temperatura
9.
Anal Chem ; 93(5): 2767-2775, 2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33474935

RESUMO

Clinical tissue specimens are often unscreened, and preparation of tissue sections for analysis by mass spectrometry imaging (MSI) can cause aerosolization of particles potentially carrying an infectious load. We here present a decontamination approach based on ultraviolet-C (UV-C) light to inactivate clinically relevant pathogens such as herpesviridae, papovaviridae human immunodeficiency virus, or SARS-CoV-2, which may be present in human tissue samples while preserving the biodistributions of analytes within the tissue. High doses of UV-C required for high-level disinfection were found to cause oxidation and photodegradation of endogenous species. Lower UV-C doses maintaining inactivation of clinically relevant pathogens to a level of increased operator safety were found to be less destructive to the tissue metabolome and xenobiotics. These doses caused less alterations of the tissue metabolome and allowed elucidation of the biodistribution of the endogenous metabolites. Additionally, we were able to determine the spatially integrated abundances of the ATR inhibitor ceralasertib from decontaminated human biopsies using desorption electrospray ionization-MSI (DESI-MSI).


Assuntos
Descontaminação/métodos , Raios Ultravioleta , Animais , Azetidinas/análise , Azetidinas/uso terapêutico , /virologia , Neoplasias de Cabeça e Pescoço/química , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Metaboloma , Naftalenos/análise , Naftalenos/uso terapêutico , Fotólise/efeitos da radiação , Ratos , Ratos Wistar , /efeitos da radiação , Espectrometria de Massas por Ionização por Electrospray/métodos , Terfenadina/química , Inativação de Vírus/efeitos da radiação
10.
Sci Rep ; 11(1): 1822, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33469049

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) responsible for the COVID-19 global pandemic has infected over 25 million people worldwide and resulted in the death of millions. The COVID-19 pandemic has also resulted in a shortage of personal protective equipment (PPE) in many regions around the world, particularly in middle- and low-income countries. The shortages of PPE, such as N95 respirators, is something that will persist until an effective vaccine is made available. Thus, devices that while being easy to operate can also be rapidly deployed in health centers, and long-term residences without the need for major structural overhaul are instrumental to sustainably use N95 respirators. In this report, we present the design and validation of a decontamination device that combines UV-C & B irradiation with mild-temperature treatment. The device can decontaminate up to 20 masks in a cycle of < 30 min. The decontamination process did not damage or reduce the filtering capacity of the masks. Further, the efficacy of the device to eliminate microbes and viruses from the masks was also evaluated. The photothermal treatment of our device was capable of eradicating > 99.9999% of the bacteria and > 99.99% of the virus tested.


Assuntos
Bactérias/efeitos da radiação , Descontaminação/métodos , Raios Ultravioleta , Vírus/efeitos da radiação , /patologia , Reutilização de Equipamento , Células HEK293 , Humanos , Microscopia de Fluorescência , /isolamento & purificação , Temperatura , Vírus/metabolismo
11.
J Hosp Infect ; 109: 82-87, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33417989

RESUMO

BACKGROUND: The SARS-CoV-2 pandemic has highlighted the urgent need for safe and effective surface decontamination methods, particularly in healthcare settings. AIM: To evaluate the effectiveness of peracetic acid (PAA) dry fogging in decontaminating healthcare facility surfaces experimentally contaminated with SARS-CoV-2. METHODS: Nine materials (stainless steel, latex painted wood, unsealed hardwood, melamine countertop, vinyl flooring, clear plastic, faux leather, computer keyboard button, and smartphone touch screen) were surface contaminated with >106 median tissue culture infectious dose (TCID50) of SARS-CoV-2, and allowed to dry before exposing to PAA dry fogging. FINDINGS: When fumigated with PAA dry fog for 1 h, no infectious SARS-CoV-2 virus was recovered from any of the experimentally inoculated surface types. By contrast, high titres of infectious virus were recovered from corresponding untreated drying controls of the same materials. CONCLUSION: Standard surface decontamination processes, including sprays and wipes, are laborious and frequently cannot completely decontaminate sensitive electronic equipment. The ease of use, low cost, and overall effectiveness of a PAA dry fogging suggest that it should be considered for decontaminating healthcare settings, particularly intensive care units where severely ill SARS-CoV-2 patients are cared for.


Assuntos
Descontaminação/métodos , Desinfetantes/farmacologia , Fumigação , Instalações de Saúde , Ácido Peracético/farmacologia , /efeitos dos fármacos , Descontaminação/instrumentação , Reutilização de Equipamento , Propriedades de Superfície/efeitos dos fármacos
12.
PLoS One ; 16(1): e0243554, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33406084

RESUMO

With COVID-19 N95 shortages, frontline medical personnel are forced to reuse this disposable-but sophisticated-multilayer respirator. Widely used to decontaminate nonporous surfaces, UV-C light has demonstrated germicidal efficacy on porous, non-planar N95 respirators when all surfaces receive ≥1.0 J/cm2 dose. Of utmost importance across disciplines, translation of empirical evidence to implementation relies upon UV-C measurements frequently confounded by radiometer complexities. To enable rigorous on-respirator measurements, we introduce a photochromic indicator dose quantification technique for: (1) UV-C treatment design and (2) in-process UV-C dose validation. While addressing outstanding indicator limitations of qualitative readout and insufficient dynamic range, our methodology establishes that color-changing dosimetry can achieve the necessary accuracy (>90%), uncertainty (<10%), and UV-C specificity (>95%) required for UV-C dose measurements. In a measurement infeasible with radiometers, we observe a striking ~20× dose variation over N95s within one decontamination system. Furthermore, we adapt consumer electronics for accessible quantitative readout and use optical attenuators to extend indicator dynamic range >10× to quantify doses relevant for N95 decontamination. By transforming photochromic indicators into quantitative dosimeters, we illuminate critical considerations for both photochromic indicators themselves and UV-C decontamination processes.


Assuntos
Descontaminação/métodos , Dispositivos de Proteção Respiratória/microbiologia , /prevenção & controle , Relação Dose-Resposta à Radiação , Contaminação de Equipamentos/prevenção & controle , Contaminação de Equipamentos/estatística & dados numéricos , Reutilização de Equipamento/estatística & dados numéricos , Humanos , Indicadores e Reagentes/efeitos da radiação , Radiometria/métodos , Sensibilidade e Especificidade , Raios Ultravioleta , Ventiladores Mecânicos/microbiologia
13.
J Trauma Acute Care Surg ; 90(4): e72-e80, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33433175

RESUMO

BACKGROUND: Health care facilities in low- and middle-income countries are inadequately resourced to adhere to current COVID-19 prevention recommendations. Recommendations for surgical emergency trauma care measures need to be adequately informed by available evidence and adapt to particular settings. To inform future recommendations, we set to summarize the effects of different personal protective equipment (PPE) on the risk of COVID-19 infection in health personnel caring for trauma surgery patients. METHODS: We conducted an umbrella review using Living Overview of Evidence platform for COVID-19, which performs regular automated searches in MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and more than 30 other sources. Systematic reviews of experimental and observational studies assessing the efficacy of PPE were included. Indirect evidence from other health care settings was also considered. Risk of bias was assessed with the AMSTAR II tool (Assessing the Methodological Quality of Systematic Reviews, Ottawa, ON, Canada), and the Grading of Recommendations, Assessment, Development, and Evaluation approach for grading the certainty of the evidence is reported (registered in International Prospective Register of Systematic Reviews, CRD42020198267). RESULTS: Eighteen studies that fulfilled the selection criteria were included. There is high certainty that the use of N95 respirators and surgical masks is associated with a reduced risk of COVID-19 when compared with no mask use. In moderate- to high-risk environments, N95 respirators are associated with a further reduction in risk of COVID-19 infection compared with surgical masks. Eye protection also reduces the risk of contagion in this setting. Decontamination of masks and respirators with ultraviolet germicidal irradiation, vaporous hydrogen peroxide, or dry heat is effective and does not affect PPE performance or fit. CONCLUSION: The use of PPE drastically reduces the risk of COVID-19 compared with no mask use in health care workers. N95 and equivalent respirators provide more protection than surgical masks. Decontamination and reuse appear feasible to overcome PPE shortages and enhance the allocation of limited resources. These effects are applicable to emergency trauma care and should inform future recommendations. LEVEL OF EVIDENCE: Review, level II.


Assuntos
/prevenção & controle , Pessoal de Saúde , Controle de Infecções , Máscaras , Centro Cirúrgico Hospitalar , Centros de Traumatologia , /epidemiologia , Descontaminação/métodos , Reutilização de Equipamento , Humanos , Controle de Infecções/instrumentação , Controle de Infecções/métodos , Máscaras/normas , Máscaras/virologia , /virologia , Equipamento de Proteção Individual/classificação , Equipamento de Proteção Individual/normas
14.
Lett Appl Microbiol ; 72(4): 366-374, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33347637

RESUMO

Decontamination of N95 filtering facepiece respirators (FFRs) is a crisis capacity strategy allowed when there are known shortages of FFRs. The application of moist heat is one decontamination method that has shown promise and is the approach approved in the Steris Steam Emergency Use Authorization (EUA). This effort examines the use of multicookers to apply moist heat, as they are available in retail stores and more affordable than methods requiring more sophisticated equipment. Four of five multicooker models examined met the acceptance criteria for the test and one model was selected for inactivation testing. Tests were performed on four different FFR models with SARS-CoV-2 suspended in culture media, simulated saliva or simulated lung fluid. Moist heat treatment reduced recoverable titres of SARS-CoV-2 virus to levels below the limit of detection in all tests. Furthermore, these four FFR models showed no loss in collection efficiency, inhalation resistance or visual damage after up to 10 decontamination cycles. Two (2) FFR models showed a slight change in strap elasticity (<9%). These data show that moist heat treatment using a multicooker is a viable option for FFR decontamination in a crisis capacity strategy.


Assuntos
/prevenção & controle , Descontaminação/métodos , Reutilização de Equipamento , Temperatura Alta , Humanos , /isolamento & purificação
15.
Exp Biol Med (Maywood) ; 246(6): 740-748, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33325749

RESUMO

Shortages of N95 respirators for use by medical personnel have driven consideration of novel conservation strategies, including decontamination for reuse and extended use. Decontamination methods listed as promising by the Centers for Disease Control and Prevention (CDC) (vaporous hydrogen peroxide (VHP), wet heat, ultraviolet irradiation (UVI)) and several methods considered for low resource environments (bleach, isopropyl alcohol and detergent/soap) were studied for two commonly used surgical N95 respirators (3M™ 1860 and 1870+ Aura™). Although N95 filtration performance depends on the electrostatically charged electret filtration layer, the impact of decontamination on this layer is largely unexplored. As such, respirator performance following decontamination was assessed based on the fit, filtration efficiency, and pressure drop, along with the relationship between (1) surface charge of the electret layer, and (2) elastic properties of the straps. Decontamination with VHP, wet heat, UVI, and bleach did not degrade fit and filtration performance or electret charge. Isopropyl alcohol and soap significantly degraded fit, filtration performance, and electret charge. Pressure drop across the respirators was unchanged. Modest degradation of N95 strap elasticity was observed in mechanical fatigue testing, a model for repeated donnings and doffings. CDC recommended decontamination methods including VHP, wet heat, and UV light did not degrade N95 respirator fit or filtration performance in these tests. Extended use of N95 respirators may degrade strap elasticity, but a loss of face seal integrity should be apparent during user seal checks. NIOSH recommends performing user seal checks after every donning to detect loss of appropriate fit. Decontamination methods which degrade electret charge such as alcohols or detergents should not be used on N95 respirators. The loss of N95 performance due to electret degradation would not be apparent to a respirator user or evident during a negative pressure user seal check.


Assuntos
/prevenção & controle , Descontaminação/métodos , /provisão & distribução , 2-Propanol/farmacologia , Detergentes/farmacologia , Humanos , Peróxido de Hidrogênio/farmacologia , Hipoclorito de Sódio/farmacologia , Eletricidade Estática , Raios Ultravioleta
16.
Int J Infect Dis ; 104: 41-44, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33383222

RESUMO

OBJECTIVES: Due to the surge in demand for N95 masks during the Covid-19 pandemic, and considering the situation in countries grappling with acute shortages of N95 masks, this study investigated the possibilities of decontamination and reuse of masks. METHODS: Three N95 masks of different makes (A, B and C) were subjected to six decontamination methods: ultraviolet (UV) irradiation, isopropyl alcohol (IPA) dip, plasma sterilization (Sterrad®), ethylene oxide (ETO, 3M®), dry heat sterilization, and moist heat sterilization (autoclaving). The integrity of the N95 masks was assessed by measuring their particle filtering efficiency at particle sizes ranging 0.3-0.5 microns. RESULTS: All the masks decontaminated with ETO and plasma sterilization retained over 95% particle filtering efficiency. Masks decontaminated using IPA dip and autoclaving showed a drop, and UV irradiation showed variations in particle size efficiency degradation after decontamination. CONCLUSIONS: Plasma sterilization is recommended for decontamination of N95 masks in low-resource settings. ETO is not recommended due to hazards associated with handling of ethylene oxide, although the filtering efficiency was retained. Since the UV irradiation method showed variations in results, evaluation of UV decontamination for N95 masks needs to be performed on a case-by-case basis.


Assuntos
/prevenção & controle , Descontaminação/métodos , Reutilização de Equipamento , Óxido de Etileno/farmacologia , Recursos em Saúde , Humanos , Índia/epidemiologia , Raios Ultravioleta
17.
Int J Food Microbiol ; 339: 109024, 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33348312

RESUMO

In-house treatment strategy for fresh produce decontamination has not been emphasized as much as industrial washing. The most common treatment for fresh produce decontamination and cleaning at home and other point-of-use places such as cafeteria is rinsing and/or soaking in a sink. In this study, an appliance utilizing UV and agitated water to decontaminate fresh produce was developed and its effectiveness was investigated in an aim to identify optimum processing parameters. Grape tomato and spinach representing two different surface smoothness were dip-inoculated in a four-strain Salmonella cocktail to reach a final population of 5-8 log CFU/g and air-dried. The produce samples were then washed in 1 gallon tap water under varying conditions, water agitation speed (0-190 RPM), sample size (50-400 g), UV intensity (0-30 mW/cm2) and treatment time (2, 5 and 10 min). In general, increasing the agitation speed and UV intensity enhanced Salmonella inactivation for both grape tomato and spinach. Sample size significantly affected the UV inactivation of Salmonella on grape tomato, but not on spinach. The effect of extending treatment time from 2 to 10 min was insignificant for almost all the UV treatments and the controls. The effect of UV intensity and treatment time on inactivation of Salmonella on spot-inoculated grape tomato and spinach was also determined. The most severe treatment used in this study, 30 mW/cm2 UV for 10 min, resulted in >4 log reductions of Salmonella dip- or spot-inoculated on grape tomato (200 g sample size and 190 RPM agitation speed) and 3.5 log reductions of Salmonella dip- or spot-inoculated on spinach (100 g sample size and 110 RPM agitation speed). We foresee that the UV appliance developed and evaluated in this study could be further fine-tuned and optimized to eventually construct a point-of-use UV appliance that can be used at home, cafeteria, restaurants, and hospitals for fresh produce decontamination and cleaning. The UV appliance could be an inexpensive and effective tool to improve fresh produce safety.


Assuntos
Descontaminação/instrumentação , Descontaminação/métodos , Escherichia coli O157/efeitos da radiação , Microbiologia de Alimentos/instrumentação , Microbiologia de Alimentos/métodos , Raios Ultravioleta , Contagem de Colônia Microbiana , Descontaminação/normas , Lycopersicon esculentum/microbiologia , Salmonella/efeitos da radiação , Spinacia oleracea/microbiologia , Água
18.
Toxicol Lett ; 339: 32-38, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33370593

RESUMO

Metal-organic frameworks (MOFs) have shown promising properties for removal of chemical warfare agents, in particular for material decontamination and functionalized fabrics. The MOF-properties could also be beneficial for skin decontamination, especially when exposed to highly toxic and low volatile nerve agents. In such exposures, efficient decontamination is crucial for adequate medical management. In the present study, seven zirconium-based MOFs were evaluated for their ability to degrade VX and subsequently tested in vitro for decontamination of VX on human dermatomed skin. Of the MOFs evaluated, MOF-808 showed the greatest ability to degrade VX in an alkaline buffer with complete degradation of VX within 5 min. PCN-777, Zr-NDC and NU-1000 displayed degradation half-lives of approximately 10 min. When including MOF-808 in a skin friendly carrier with slightly acidic pH, a decreased agent degradation rate was observed, requiring over 24 h to reach complete degradation. In skin decontamination experiments, MOF-808 enhanced the efficacy compared to the carrier alone, essentially by improved agent absorption. Adding MOF-808 to Reactive Skin Decontamination Lotion (RSDL) did not improve the high effectiveness of RSDL alone. The present study showed that including MOF in skin decontamination lotions could be beneficial. Further studies should include optimizing the particulates and formulations.


Assuntos
Substâncias para a Guerra Química/toxicidade , Descontaminação/métodos , Estruturas Metalorgânicas/uso terapêutico , Agentes Neurotóxicos/toxicidade , Compostos Organotiofosforados/toxicidade , Pele/efeitos dos fármacos , Zircônio/uso terapêutico , Células Cultivadas/efeitos dos fármacos , Substâncias para a Guerra Química/metabolismo , Humanos , Agentes Neurotóxicos/metabolismo , Compostos Organotiofosforados/metabolismo , Creme para a Pele
19.
Int J Food Microbiol ; 337: 108936, 2021 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-33161345

RESUMO

Development of novel and effective decontamination technologies to ensure the microbiological safety of fresh produce has gained considerable attention, mainly driven by numerous outbreaks. This work presented the first approach regarding to the application of the previously reported hurdle technologies on the sanitization of artificially contaminated cherry tomatoes. Thyme (Thymus daenensis) essential oil nanoemulsion (TEON, 8.28 nm in diameter with a narrow size distribution) was formulated via ultrasonic nanoemulsification, showing remarkably improved antimicrobial activity against Escherichia coli (E. coli) O157:H7, compared to the coarse emulsion. The antimicrobial effect of ultrasound (US), thyme essential oil nanoemulsion (TEON) and the combination of both treatments was assessed against E. coli O157:H7. The remarkable synergistic effects of the combined treatments were achieved, which decontaminated the E. coli populations by 4.49-6.72 log CFU/g on the surface of cherry tomatoes, and led to a reduction of 4.48-6.94 log CFU/sample of the total inactivation. TEON combined with US were effective in reducing the presence of bacteria in wastewater, which averted the potential detrimental effect of cross-contamination resulted from washing wastewater in fresh produce industry. Moreover, the treatments did not noticeably alter the surface color and firmness of cherry tomatoes. Therefore, ultrasound combined with TEON is a promising and feasible alternative for the reduction of microbiological contaminants, as well as retaining the quality characteristics of cherry tomatoes.


Assuntos
Descontaminação/métodos , Escherichia coli O157/efeitos dos fármacos , Escherichia coli O157/efeitos da radiação , Microbiologia de Alimentos/métodos , Óleos Voláteis/farmacologia , Ondas Ultrassônicas , Contagem de Colônia Microbiana , Lycopersicon esculentum/microbiologia
20.
Health Secur ; 19(1): 100-107, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33332230

RESUMO

In the event of an incident involving the release of hazardous material (eg, chemical, biological, radiological, or nuclear agents), key actions can be taken to reduce harm and protect the people involved. The quicker actions can be taken, the less harm will occur. Guidance is, therefore, needed to help nonspecialist members of the public to act rapidly before emergency responders arrive. The "Remove, Remove, Remove" campaign includes critical information for anyone who is at or near the immediate scene of a hazardous material release. Using a representative sample of 1,000 members of the UK population, this study examined the impact of the information campaign on knowledge and perceptions both before and during the immediate response to an incident. Findings showed that perceptions of the information were positive, with respondents stating that the information was useful and that the recommended actions would be effective. Respondents also stated they would be willing and able to perform the actions during a real incident. Additionally, the respondents' knowledge and confidence in taking protective actions increased significantly after receiving the campaign information, and they overwhelmingly agreed that they would want to receive this information if it were available before an incident. The findings of the survey support the use of the "Remove, Remove, Remove" information before and during hazardous materials incidents.


Assuntos
Comunicação , Desastres , Substâncias Perigosas , Adulto , Derramamento de Material Biológico , Vazamento de Resíduos Químicos , Descontaminação/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Liberação Nociva de Radioativos , Inquéritos e Questionários , Reino Unido
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...