Use of Hydrogen Peroxide Vapour for Microbiological Disinfection in Hospital Environments: A Review.

Disinfection of nosocomial pathogens in hospitals is crucial to combat healthcare-acquired infections, which can be acquired by patients, visitors and healthcare workers. However, the presence of a wide range of pathogens and biofilms, combined with the indiscriminate use of antibiotics, presents infection control teams in healthcare facilities with ongoing challenges in the selection of biocides and application methods. This necessitates the development of biocides and innovative disinfection methods that overcome the shortcomings of conventional methods. This comprehensive review finds the use of hydrogen peroxide vapour to be a superior alternative to conventional methods. Motivated by observations in previous studies, herein, we provide a comprehensive overview on the utilisation of hydrogen peroxide vapour as a superior high-level disinfection alternative in hospital settings. This review finds hydrogen peroxide vapour to be very close to an ideal disinfectant due to its proven efficacy against a wide range of microorganisms, safety to use, lack of toxicity concerns and good material compatibility. The superiority of hydrogen peroxide vapour was recently demonstrated in the case of decontamination of N95/FFP2 masks for reuse to address the critical shortage caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the COVID-19 pandemic. Despite the significant number of studies demonstrating antimicrobial activity, there remains a need to critically understand the mechanism of action by performing studies that simultaneously measure damage to all bacterial cell components and assess the correlation of this damage with a reduction in viable cell count. This can lead to improvement in antimicrobial efficacy and foster the development of superior approaches.

Improved childhood asthma control after exposure reduction interventions for desert dust and anthropogenic air pollution: the MEDEA randomised controlled trial.

INTRODUCTION: Elevated particulate matter (PM) concentrations of anthropogenic and/or desert dust origin are associated with increased morbidity among children with asthma. OBJECTIVE: The Mitigating the Health Effects of Desert Dust Storms Using Exposure-Reduction Approaches randomised controlled trial assessed the impact of exposure reduction recommendations, including indoor air filtration, on childhood asthma control during high desert dust storms (DDS) season in Cyprus and Greece. DESIGN, PARTICIPANTS, INTERVENTIONS AND SETTING: Primary school children with asthma were randomised into three parallel groups: (a) no intervention (controls); (b) outdoor intervention (early alerts notifications, recommendations to stay indoors and limit outdoor physical activity during DDS) and (c) combined intervention (same as (b) combined with indoor air purification with high efficiency particulate air filters in children's homes and school classrooms. Asthma symptom control was assessed using the childhood Asthma Control Test (c-ACT), spirometry (forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC)) and fractional exhaled nitric oxide (FeNO). RESULTS: In total, 182 children with asthma (age; mean=9.5, SD=1.63) were evaluated during 2019 and 2021. After three follow-up months, the combined intervention group demonstrated a significant improvement in c-ACT in comparison to controls (ß=2.63, 95% CI 0.72 to 4.54, p=0.007), which was more profound among atopic children (ß=3.56, 95% CI 0.04 to 7.07, p=0.047). Similarly, FEV1% predicted (ß=4.26, 95% CI 0.54 to 7.99, p=0.025), the need for any asthma medication and unscheduled clinician visits, but not FVC% and FeNO, were significantly improved in the combined intervention compared with controls. CONCLUSION: Recommendations to reduce exposure and use of indoor air filtration in areas with high PM pollution may improve symptom control and lung function in children with asthma. TRIAL REGISTRATION NUMBER: NCT03503812.

Improved indoor air quality during desert dust storms: The impact of the MEDEA exposure-reduction strategies.

Desert dust storms (DDS) are natural events that impact not only populations close to the emission sources but also populations many kilometers away. Countries located across the main dust sources, including countries in the Eastern Mediterranean, are highly affected by DDS. In addition, climate change is expanding arid areas exacerbating DDS events. Currently, there are no intervention measures with proven, quantified exposure reduction to desert dust particles. As part of the wider "MEDEA" project, co-funded by LIFE 2016 Programme, we examined the effectiveness of an indoor exposure-reduction intervention (i.e., decrease home ventilation during DDS events and continuous use of air purifier during DDS and non-DDS days) across homes and/or classrooms of schoolchildren with asthma and adults with atrial fibrillation in Cyprus and Crete-Greece. Participants were randomized to a control or intervention groups, including an indoor intervention group with exposure reduction measures and the use of air purifiers. Particle sampling, PM10 and PM2.5, was conducted in participants' homes and/or classrooms, between 2019 and 2022, during DDS-free weeks and during DDS days for as long as the event lasted. In indoor and outdoor PM10 and PM2.5 samples, mass and content in main and trace elements was determined. Indoor PM2.5 and PM10 mass concentrations, adjusting for premise type and dust conditions, were significantly lower in the indoor intervention group compared to the control group (PM2.5-intervention/PM2.5-control = 0.57, 95% CI: 0.47, 0.70; PM10-intervention/PM10-control = 0.59, 95% CI: 0.49, 0.71). In addition, the PM2.5 and PM10 particles of outdoor origin were significantly lower in the intervention vs. the control group (PM2.5 infiltration intervention-to-control ratio: 0.49, 95% CI: 0.42, 0.58; PM10 infiltration intervention-to-control ratio: 0.68, 95% CI: 0.52, 0.89). Our findings suggest that the use of air purifiers alongside decreased ventilation measures is an effective protective measure that reduces significantly indoor exposure to particles during DDS and non-DDS in high-risk population groups.

Responses of schoolchildren with asthma to recommendations to reduce desert dust exposure: Results from the LIFE-MEDEA intervention project using wearable technology.

Current public health recommendations for desert dust storms (DDS) events focus on vulnerable population groups, such as children with asthma, and include advice to stay indoors and limit outdoor physical activity. To date, no scientific evidence exists on the efficacy of these recommendations in reducing DDS exposure. We aimed to objectively assess the behavioral responses of children with asthma to recommendations for reduction of DDS exposure. In two heavily affected by DDS Mediterranean regions (Cyprus & Crete, Greece), schoolchildren with asthma (6-11 years) were recruited from primary schools and were randomized to control (business as usual scenario) and intervention groups. All children were equipped with pedometer and GPS sensors embedded in smartwatches for objective real-time data collection from inside and outside their classroom and household settings. Interventions included the timely communication of personal DDS alerts accompanied by exposure reduction recommendations to both the parents and school-teachers of children in the intervention group. A mixed effect model was used to assess changes in daily levels of time spent, and steps performed outside classrooms and households, between non-DDS and DDS days across the study groups. The change in the time spent outside classrooms and homes, between non-DDS and DDS days, was 37.2 min (pvalue = 0.098) in the control group and -62.4 min (pvalue < 0.001) in the intervention group. The difference in the effects between the two groups was statistically significant (interaction pvalue < 0.001). The change in daily steps performed outside classrooms and homes, was -495.1 steps (pvalue = 0.350) in the control group and -1039.5 (pvalue = 0.003) in the intervention group (interaction pvalue = 0.575). The effects on both the time and steps performed outside were more profound during after-school hours. To summarize, among children with asthma, we demonstrated that timely personal DDS alerts and detailed recommendations lead to significant behavioral changes in contrast to the usual public health recommendations.

Attributional life cycle assessment of biofuels for shipping: Addressing alternative geographical locations and cultivation systems.

The purpose of this study is to evaluate a life cycle assessment of straight vegetable oil (SVO) and biodiesel addressing alternative upstream pathways. The pathways are SVO and biodiesel produced in the United Kingdom (UK) using European rapeseed and also, SVO and biodiesel produced in the UK using soybean grain and soybean oil imported from Argentina. Four environmental impact categories have been assessed using the SimaPro (ReCiPe life-cycle impact assessment) method: this includes global warming potential (GWP); acidification; eutrophication and particulate matter. Rapeseed based biofuel had the lowest emission impact in terms of GHG emissions. Significant greenhouse gas (GHG) emissions can result from land use change due to the expansion and cultivation of soybean in Argentina. When land use change is not considered, the soy based biofuel system has the lowest GHG impact with more than 70% GHG emission reduction. The GHG emission at cultivation stage far outweighs the impacts of the other life-cycle stages irrespective of the feedstock used for the biofuel production systems. The use of fertilizers and associated soil emissions are the main contributors. The environmental impacts of biofuel can be reduced by avoiding land use change, improving soil management practices and yield, and also optimizing transportation routes. Effective implementation of options for biofuels production were explored to improve sustainability in shipping.

Revisiting the mystery of recent stratospheric temperature trends.

Simulated stratospheric temperatures over the period 1979-2016 in models from the Chemistry-Climate Model Initiative (CCMI) are compared with recently updated and extended satellite observations. The multi-model mean global temperature trends over 1979- 2005 are -0.88 ± 0.23, -0.70 ± 0.16, and -0.50 ± 0.12 K decade-1 for the Stratospheric Sounding Unit (SSU) channels 3 (~40-50 km), 2 (~35-45 km), and 1 (~25-35 km), respectively. These are within the uncertainty bounds of the observed temperature trends from two reprocessed satellite datasets. In the lower stratosphere, the multi-model mean trend in global temperature for the Microwave Sounding Unit channel 4 (~13-22 km) is -0.25 ± 0.12 K decade-1 over 1979-2005, consistent with estimates from three versions of this satellite record. The simulated stratospheric temperature trends in CCMI models over 1979-2005 agree with the previous generation of chemistry-climate models. The models and an extended satellite dataset of SSU with the Advanced Microwave Sounding Unit-A show weaker global stratospheric cooling over 1998-2016 compared to the period of intensive ozone depletion (1979-1997). This is due to the reduction in ozone-induced cooling from the slow-down of ozone trends and the onset of ozone recovery since the late 1990s. In summary, the results show much better consistency between simulated and satellite observed stratospheric temperature trends than was reported by Thompson et al. (2012) for the previous versions of the SSU record and chemistry-climate models. The improved agreement mainly comes from updates to the satellite records; the range of simulated trends is comparable to the previous generation of models.

Sensory Threshold Studies of Picrocrocin, the Major Bitter Compound of Saffron.

This study is part of a wider project on the bitter taste of saffron and its preparations. A deeper knowledge on the taste perception of picrocrocin is necessary in order to develop products that satisfy consumer senses and provide them with adequate amounts of saffron major constituents, also appreciated for bioactivity. A systematic approach on the bitterness of picrocrocin, the major responsible compound, was conducted. A panel was trained specifically for the determination of taste detection and recognition thresholds of picrocrocin, which were found to be 5.34 and 7.26 mg/L, respectively, using the Ascending Forced Choice of Limits methodology. The threshold values were examined in water in absence and presence of other saffron constituents and ethanol and were found to decrease when served hot (61 ± 4 °C). Bitterness was enhanced in 40% (v/v) aqueous ethanol. In both aqueous and ethanol extracts, the presence of saffron volatiles improved bitterness perception. The usefulness of the study was tested in the case of commercial saffron based infusions.

Revisiting extraction of bioactive apocarotenoids from Crocus sativus L. dry stigmas (saffron).

An ultrasound assisted extraction method is proposed for the recovery of bioactive glycosides (i.e. crocins and picrocrocin) from Crocus sativus L. dry stigmas using aqueous methanol. Response surface methodology (RSM) was employed to optimize the extraction parameters, namely, the percentage of methanol (%), the duration (min) and the duty cycles (s) of sonication. Optical microscopy, spectrophotometry and RP-HPLC-DAD were employed to follow pros and cons of the process. Additional experiments were conducted to compare recoveries with those under other agitation conditions (e.g. magnetic stirring according to ISO 3632-2 standard). The percentage of methanol, the sonication duration and duty cycles combination that can be recommended as optimum for the recovery of crocins and picrocrocin were 50%, 30 min, 0.2s and 0.44%, 30 min, 0.6s, respectively. Picrocrocin levels were not influenced dramatically under the optimum conditions for crocins extraction (11±2 instead of 12±1 mg kg(-1) dry stigmas, respectively) so that these can be considered optimum for both categories of tested compounds. Ultrasound assisted extraction speeded up further recovery of these precious apocarotenoids. Our findings for extraction conditions are useful for both industrial and analytical applications and should be considered in a forthcoming revision of the ISO 3632-2 technical standard.