Search Results (75)

Air sanitization is an important non-pharmaceutical intervention for mitigating the risk of indoor pathogen spreading. A dipropylene glycol-containing air sanitizer was tested against aerosolized Staphylococcus aureus and Klebsiella pneumoniae. The bacteria, suspended in a soil load, were aerosolized using a six-jet Collison nebulizer with pressurized air. The 25-m³ (~900 ft³) aerobiology chamber was maintained at 22 ± 2 °C and 50 ± 5% relative humidity per the U.S. Environmental Protection Agency’s 2012 Guidelines on air sanitizers. An initial 2-min air sample was collected from the chamber using a slit-to-agar sampler containing 150-mm Petri plates, with Trypticase soy agar (TSA) containing neutralizers to quench the microbicidal activity of the air sanitizer, to determine the initial bacterial challenge in the air. The air sanitizer was sprayed into the chamber from pressurized cans. Additional air samples were collected from the chamber over 10 min to detect surviving bacteria. The TSA plates were then incubated aerobically at 36 ± 1 °C for 90 ± 4 h and scored for bacterial colony-forming units. A 30-s spray of the air sanitizer reduced infectious S. aureus and K. pneumoniae titers by 3.0 log₁₀ (99.9%) in 3.2 ± 0.3 min and 1.2 ± 0.0 min, respectively. Based on these findings, the EPA granted registration of the air sanitizer as the first product of its kind for indoor air sanitization. Full article

Smart environments exploit rising technologies like Internet of Things (IoT) and edge intelligence (EI) to achieve unseen effectiveness and efficiency in every tasks, including air sanitization. The latter represents a key preventative measure–made even more evident by the COVID-19 pandemic–to significantly reduce disease transmission and create healthier and safer indoor spaces, for the sake of its occupants. Therefore, in this paper, we present an IoT-based system aimed at the continuous monitoring of the air quality and, through EI techniques, at the proactively activation of ozone lamps, while ensuring safety in sanitization. Indeed, these devices ensure extreme effectiveness in killing viruses and bacteria but, due to ozone toxicity, they must be properly controlled with advanced technologies for preventing occupants from dangerous exposition as well as for ensuring system reliability, operational efficiency, and regulatory compliance. Full article

Infections in confined environments can spread by direct contact, contaminated surfaces, and airborne transmission. This is critical in prison facilities, where cleaning and sanitary conditions are inadequate. An alternative is the development of antimicrobial surfaces. A new antimicrobial coating was developed by incorporating copper microparticles into a standard commercial paint, aiming to reduce the concentration of bacteria on surfaces by granting antimicrobial properties to surfaces. The copper additive comprised Cu₂Cl(OH)₃ deposited on polyhedral zeolite. The efficacy of this coating was evaluated in detention cells in a police station, which are temporary prisons and inherently dirty environments. The experiment compared a cell painted with the copper additive coating and a control cell with the standard paint. Viable coliforms were measured on different surfaces and in the air for five months under normal usage. Bacterial load was reduced by ca. 68% by the copper-amended paint on cement surfaces. Surprisingly, airborne viable coliforms were reduced by ca. 87% in the detention cell treated with the copper coating. This research highlights the potential of antimicrobial coatings in controlling the spread of infections through contact with contaminated surfaces and emphasizes the significant reduction in airborne bacterial load. It is especially relevant for controlling infections where sanitization is limited but can be extended to other built environments, such as healthcare facilities. Full article

In 2015, the Japanese public broadcaster NHK aired an educational series that re-examined traditional fairy tales by putting their characters on trial for their immoral behavior, such as revenge, violence, and dishonesty. These tales, rooted in premodern Japanese folklore, were widely available in various book formats by the late nineteenth century and, unlike modern adaptations, they did not sanitize violence or evil. This study analyzes four miniature picture books from the late nineteenth century that recount the story, Kachikachi yama (The Crackling Mountain). This analysis focuses on both verbal and visual representations of good and evil, with attention to themes of loyalty, filial piety, and virtuous revenge. The findings reveal that these picture books presented young readers with complex moral lessons, where the boundaries between good and evil were blurred. Additionally, they illuminate the prevailing image of children during that era, depicting them as “little adults” expected to be educated and prepared for the practical realities of the adult world. Full article

Leaf recycling, a crucial component of urban environmental protection, aims to systematically collect and reuse fallen leaves on streets. At present, fallen leaves are usually cleaned manually by sanitation workers, and environmental protection departments then use special cars to transport fallen leaves to treatment stations for incineration. This not only requires a significant amount of labor and material resources but also causes air pollution and wastes fallen leaves. In this study, a collecting, crushing, and recycling vehicle was designed to solve this problem. The proposed device significantly improves the efficiency of collecting fallen leaves and facilitates their secondary utilization. The design process is described in detail, including the working design of the entire device, static analysis, and transmission system design. The entire vehicle model was 3D printed to verify that the initial design concept satisfies the assembly and production requirements of the device. Full article

Syndemics, the adverse interaction of two or more coterminous diseases or other negative health conditions, have probably existed since human settlement, plant and animal domestication, urbanization, and the growth of social inequality beginning about 10–12,000 years ago. These dramatic changes in human social evolution significantly increased opportunities for the spread of zoonotic infectious diseases in denser human communities with increased sanitation challenges. In light of a growing body of research that indicates that anthropogenic air pollution causes numerous threats to health and is taking a far greater toll on human life and wellbeing than had been reported, this paper proposes the possibility that air pollution is now the primary driver of infectious disease syndemics. In support of this assertion, this paper reviews the growth and health impacts of air pollution, the relationship of air pollution to the development and spread of infectious diseases, and reported cases of air pollution-driven infectious disease syndemics, and presents public health recommendations for leveraging the biosocial insight of syndemic theory in responding to infectious disease. Full article

The postharvest life of strawberries is short, and disinfection processes for fresh-cut and frozen strawberries are needed to address the risk posed by foodborne pathogens in this kind of product. For this, a process involving immersion in a 40 mg L⁻¹ peracetic acid (PA) solution accompanied by the use of an emerging technology, ultraviolet-C for 2 min, was studied for its impact on strawberry quality and microbial load as a novel alternative method to chlorine sanitation. The shelf life of the washed strawberries was evaluated in fresh (whole or fresh-cut) product for 11 days at 4 °C and in product that had been frozen for 12 months at –20 °C (air or modified atmosphere, 20% CO₂, 5% O₂, and 75% N₂). After washing, total aerobic mesophylls, yeast, and mold decreased by 0.5–1.0 log units and these counts remained low during storage. The fresh and fresh-cut fruits’ firmness (2.3 ± 0.5 N at day 11) and lightness (expressed by L*, averaging 31.0 ± 0.1) were maintained. Although antioxidant activity, expressed by the amount of radical 2,2-diphenyl-1-picrylhydrazyl (DPPH), decreased during storage in fresh-cut samples, total ferric reducing antioxidant power (FRAP), total phenolic content, and total anthocyanin content were maintained in all the formats during storage (averaging 1.33 ± 0.04 g kg⁻¹ ascorbic acid equivalents, 0.212 ± 0.01 g kg⁻¹ gallic acid equivalents, and 0.03 ± 0.01 g kg⁻¹ pelargonidine-3-glucoside). An increase in red color (from 32.1 to 39.3 a* values) and a loss of firmness of up to 46.8% was observed after the first month of frozen storage with no changes in the nutritional quality. Considering the sanitizing effect of water UV-C with peracetic acid (WUVPA) and the results obtained in the present study, the addition of this process in the production chain of strawberries could be an effective method to maintain the shelf life of the fruits, especially for fresh-cut strawberries. Full article

Bioaerosols and pathogens in indoor workplaces and residential environments are the primary culprits of several infections. Techniques for sanitizing air and surfaces typically involve the use of UV rays or chemical sanitizers, which may release chemical residues harmful to human health. Essential oils, natural substances derived from plants, which exhibit broad antimicrobial properties, could be a viable alternative for air and surface sanitation. The objective of this study has been to investigate the efficacy of thyme essential oil (TEO) in environmental sanitation processes. In Vitro assays through agar well diffusion, disk volatilization and tube dilution methods revealed significant antimicrobial activity of TEO 100% against foodborne and environmental isolates, with both bacteriostatic/fungistatic and bactericidal/fungicidal effects. Therefore, aqueous solutions of TEO 2.5% and 5% were formulated for air sanitation through nebulization and surface disinfection via direct contact. Bioaerosol samples and surface swabs were analyzed before and after sanitation, demonstrating the efficacy of aqueous solutions of TEO in reducing mesophilic and psychrophilic bacteria and environmental fungi levels in both air and on surfaces. The obtained results prove the antimicrobial potential of aqueous solutions of TEO in improving indoor air quality and surface cleanliness, suggesting thyme essential oil as an effective and safe natural sanitizer with minimal environmental impact compared to dangerous chemical disinfectants. Full article

With the pervasive consumption (currently >65% of total market shares and steadily increasing) of petroleum-derived synthetic textiles, the escalating concern of microfiber fragment (MF) pollution has emerged as a formidable menace to our ecological equilibrium. Over the lifetime (pre- and post-consumption) of these textiles, they shed tiny fibers recognized as MFs. These MFs are carriers of persistent organic pollutants and have been linked to cytotoxicity, oxidative stress, and genotoxicity, even at minimal exposures via air and water sources. Grounded in the state-of-the-art literature, this review discusses the primary and secondary sources of MF release, their fate, transport, environmental impacts, and novel technologies for MF pollutant remediation. Our results infer that MF pollution is a multifactorial issue with serious environmental and public health implications, as studies reported their presence in human blood, feces, and urine samples. We recommend a multifaceted approach to increase sanitation coverage, ensuring adequate wastewater treatment prior to environmental discharge for MF pollution mitigation. Additionally, transformation is warranted for consumers’ use, care, and purchase behavior of textile products. Government regulation of fast fashion (a major user of synthetic textiles), exemplified by recent French legislation, is essential to preventing microfiber pollution. We urge similar policy-making efforts globally to safeguard public health. Full article

This study assessed the extent of L. monocytogenes transfer from onions to the surface of a commercial dicer, from inoculated onions to uninoculated onions, and the efficacy of various sanitizers during the subsequent flume washing of diced onions. Spanish yellow onions (Allium cepa L.) were dip-inoculated in a 3-strain avirulent L. monocytogenes cocktail (5.9 or 4.2 log CFU/50 g) and air-dried. After dicing one 2.2 kg batch of onions inoculated at ~5.9 log CFU/50 g followed by ten uninoculated batches of 2.2 kg each, L. monocytogenes progressively decreased from 4.6 to 2.6 log CFU/50 g in baches 1 through 10, respectively. After onions inoculated at ~4.0 log CFU/g were diced and flume washed for 2 min in tap water, electrolyzed water containing 55 ppm free chlorine, 80 ppm free chlorine from a commercial sanitizer, or 80 ppm peroxyacetic acid and dewatered on a mechanical shaker table, L. monocytogenes populations decreased 0.4, 0.3, 1.4, and 1.0 log, respectively, with populations of ~1.2 log CFU/mL in water for all three sanitizers. These findings should be useful in future risk assessments and aid in the development of improved industry guidelines to better enhance the safety of diced onions. Full article

The consumer demand for organic food including apples is increasing worldwide. Despite favorable environmental and health benefits, organic farming bears also disadvantages like high amounts of fruit losses due to storage rot. A novel treatment with plasma-processed air (PPA) to sanitize organic apples is investigated. The plasma source for the generation of PPA was operated at a frequency of 2.45 GHz, a power output of 1.1 kW and a gas flow of 18 standard liters per minute. The antimicrobial efficiency of the PPA was tested on the natural load of organic apples (cultivar Natyra) with a load ranging from 10⁴ to 10⁶ CFU/mL in an experimental laboratory setup. A larger application was applied on artificially inoculated (Pseudomonas fluorescens~10⁸ CFU/mL and Pezicula malicorticis~10⁶ CFU/mL) organic apples to test the up-scalability of the PPA treatment. The apples were photographically documented and their texture was analyzed during the 26-day storage phase to investigate the influence of the PPA treatment on the appearance of the apples. The laboratory experiments resulted in a log₁₀-reduction of one to two log₁₀ levels compared to untreated and compressed-air-treated apples. For apples inoculated with P. fluorescens, the up-scaled procedure resulted in up to four levels of log₁₀ reduction. In apples inoculated with P. malicorticis, the up-scaled procedure resulted in no reduction. This indicates that the application of PPA to organic apples can be effective for bacteria but needs to be optimized for fungi. Therefore, further testing is needed to validate the results. Full article

According to many national legislations, biological agents represent an occupational hazard that must be managed in order to ensure safety at workplace. Bioaerosols have been associated to many pathological conditions but, despite many efforts, precise threshold limit values (TLV) are still undefined. We planned and conducted an environmental study concerning a typical restaurant that aimed to evaluate: (1) the occupational exposure to bacterial and fungal bioaerosol; (2) the efficacy of a photocatalytic air purifier device in mitigating such exposure. This observational study evaluated two dining rooms (Area 1 and Area 2) of a restaurant which can be considered typical during two consecutive weeks. Based on a national protocol, we monitored total bacterial and mycotic loads searching for two typologies of bacteria, psychrophilic bacteria (environmental contamination) along with mesophilic bacteria (human or animal origin source), and two types of fungi, mold and yeast. Baseline total bacterial load was 346.8 CFU/m³ for Area 1 and 412.9 CFU/m³ for Area 2. When the sanitizing device was operative, the total bacterial load decreased to 202.7 CFU/m³ (−41.50%—p value: <0.01) for Area 1 and to 342.2 CFU/m³ ($-1$7.10%—p value: 0.06) for Area 2. Considering the fungal load, the mean baseline value was 189.7 CFU/m³ for Area 1 and 141.1 CFU/m³ for Area 2. When the device was kept on, the total fungal load was 108.0 CFU/m³ ($-4$3.10%—p value: 0.055) for Area 1 and 205.0 CFU/m³ (+45.30%—p value: 0.268) for Area 2. Our findings supported the conclusion that, concerning the occupational risk derived from biological agents, a typical restaurant should be considered relatively safe. In order to mitigate or limit any possible increase of such risk, a photocatalytic device may be helpful, but not against the pollution caused by mold or yeasts. Our research also reaffirmed the need of further research assessing the kind of relationship between diseases and exposure levels, before considering the need of setting precise threshold limit values. Full article

Surgery is one of the most energy-intensive branches of healthcare. Although the COVID-19 pandemic has reduced surgical volumes, infection control protocols have increased the ecological footprint of surgery owing to the extensive use of personal protective equipment, sanitation, testing and isolation resources. The burden of environmental diseases requiring surgical care, the international commitment towards environmental sustainability and the global efforts to return to the pre-pandemic surgical workflow call for action towards climate-friendly surgery. The authors have searched the peer-reviewed and gray literature for clinical studies, reports and guidelines related to the ecological footprint of surgical care and the available solutions and frameworks to reduce it. Numerous studies concede that surgery is associated with a high rate of energy utilization and waste generation that is comparable to major non-medical sources of pollution. Recommendations and research questions outlining environmentally sustainable models of surgical practices span from sanitation and air quality improvement systems to the allocation of non-recyclable consumables and energy-efficient surgical planning. The latter are particularly relevant to infection control protocols for COVID-19. Paving the way towards climate-friendly surgery is a worthy endeavor with a major potential to improve surgical practice and outcomes in the long term. Full article

Good hand hygiene has proven to be essential in reducing the uncontrolled spread of human pathogens. Cold atmospheric plasma (CAP) may provide an alternative to disinfecting hands with ethanol-based handrubs when handwashing facilities are unavailable. CAP can be safely applied to the skin if the energy is well controlled. In this study, radio frequency (RF) and direct current (DC) plasma sources were built with a pin-to-mesh electrodes configuration inside a fused silica tube with a 5 mm inner diameter. Microbiological assays based on EN 13697:2015+A1:2019 using Escherichia coli DSM 682 or Staphylococcus epidermidis DSM 20044 were used to examine the antimicrobial effect of various plasma conditions. Metal and silicone disks that model skin were used as inoculation matrices. The prototype air RF CAP achieved significant disinfection in the MHz range on stainless steel and silicone substrates. This is equivalent to half the performance of direct current CAP, which is only effective on conductive substrates. Using only electricity and air CAP could, with further optimization to increase its efficacy, replace or complement current hand disinfection methods, and mitigate the economic burden of public health crises in the future. Full article

Introduction: There are several risk factors attributed to tuberculosis (TB) mortality and morbidity. There are few studies and systematic reviews showing the association of silicosis and tuberculosis at a country level. Very limited studies have been conducted using multi-country data in studying the association of incidence of silicosis with TB mortality and morbidity. Hence, the aim of this research was to explore the association of incidence of silicosis and other important risk factors with TB mortality and morbidity using multi-country data. Methods: Data from 217 WHO region countries were utilized, sourcing TB-related statistics from the Institute of Health Metrics and Evaluation and additional risk factors from the Demographic and Health Survey, Global Burden of Disease, and World Bank for 2019. Regression analysis was conducted to examine the association between silicosis incidence and TB outcomes. Results: The study found an average silicosis incidence of 121.92 per 100,000 population. Additionally, 62.69% of the sample population are exposed to air pollution from solid fuel cooking. Sanitation access stands at an average of 59.67%. Regression outcomes indicate that while alcohol consumption’s influence on TB is not statistically significant, a unit increase in silicosis incidence significantly elevates TB deaths (235.9, p = 0.005), YLL (9399.3, p = 0.011), and YLD (910.8, p = 0.002). Conclusion: The burden of silicosis is found to be one of the important determinants of deaths, YLL, and YLD due to tuberculosis. Country-specific strategies to prevent and control silicosis is a need of the hour. Full article