Approximately 70 % of the area highly 137Cs-contaminated by the Fukushima Daiichi Nuclear Power Plant accident is forested. Decontamination works in most of these forests have not progressed, and the ...forestry industry remains stagnant. Although the long-term dynamics of 137Cs in the forest ecosystem will be controlled by the amount of 137Cs absorbed by roots in the future, temporal changes in 137Cs of tree roots have rarely been reported. In the present study, we monitored the depth distribution of 137Cs in the soil and absorptive very fine (VF) roots of 0.5 mm or less in a Japanese cedar forest from 2011 to 2023. As a result, the 137Cs inventory in the mineral soil increased over time due to the migration from the forest canopy and litter layers, whereas that in the VF roots tended to decrease since 2020, although there was a large variation. Temporal decrease in the exchangeable 137Cs fraction with fixation and temporal increase in VF root biomass with their growth were not clearly observed, the 137Cs concentration in the VF roots at 0–2 cm decreased with the decrease in 137Cs concentration in the litter layers. Although the 137Cs concentration in the VF roots below 2 cm tended to increase with increasing 137Cs concentration in the soil at the same depth, the downward migration of 137Cs within the soil can reduce the amount of 137Cs absorbed by roots because the VF root biomass decreases exponentially with depth. In other words, 137Cs can be removed from the long-term active cycles of forest ecosystems as they migrate deeper into the soil. This natural migration process can be regarded as a “self-cleaning” of the forest ecosystem, the green and sustainable remediation using such self-cleaning should be actively adopted for the future forest management.
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•137Cs uptake amount by root determines long-term contamination in forest ecosystem.•There are few time series data of 137Cs in tree roots after the nuclear accident.•We monitored the depth distribution of 137Cs in cedar tree roots from 2011 to 2023.•The inventory of 137Cs in roots decreased after 2020 due to downward migration.•Downward migration of 137Cs can be regarded as a “self-cleaning” of the forest.
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•The best conditions for the toxic elements removal from CCA-treated wood were studied.•Acid extraction was effective in the removal of Cu, Cr and As from eucalyptus wood.•The waste ...was no longer hazardous and can be recycled.•The methodology presents significant potential for use in managing this waste type.
Preservatives such as chromated copper arsenate (CCA) are used to increase the resistance of wood to deterioration. The components of CCA are highly toxic, resulting in growing concern over the disposal of the waste generated. The aim of this study was to investigate the removal of Cu, Cr and As present in CCA-treated eucalyptus wood from utility poles removed from service in southern Brazil, in order to render them non-hazardous waste. The removal was carried out by acid leaching in bench-scale and applying optimal extractor concentration, total solid content, reactor volume, temperature and reaction time obtained by factorial experiments. The best working conditions were achieved using three extraction steps with 0.1molL−1H2SO4 at 75°C for 2h each (total solid content of 15%), and 3 additional 1h-long washing steps using water at ambient temperature. Under these conditions, removal of 97%, 85% and 98% were obtained for Cu, Cr and As, respectively, rendering the decontaminated wood non-hazardous waste. The wastewater produced by extraction showed acid pH, high organic loading as well as high concentrations of the elements, needing prior treatment to be discarded. However, rinsing water can be recycled in the extraction process without compromising its efficiency. The acid extraction is a promising alternative for CCA removal from eucalyptus wood waste in industrial scale.
Purpose
Although the proportion of immunocompromised patients admitted to the ICU is increasing, data regarding specific management, including acquired infection (ICU-AI) prophylaxis, in this setting ...are lacking. We aim to investigate the effect of multiple-site decontamination regimens (MSD) in immunocompromised patients.
Methods
We conducted a prospective pre-/post-observational study in 2 ICUs in Bretagne, western France. Adults who required mechanical ventilation for 24 h or more were eligible. During the study period, MSD was implemented in participating ICUs in addition to standard care. It consists of the administration of topical antibiotics (gentamicin, colistin sulfate, and amphotericin B), four times daily in the oropharynx and the gastric tube, 4% chlorhexidine bodywash once daily, and a 5-day nasal mupirocin course.
Results
Overall, 295 immunocompromised patients were available for analysis (151 in the post-implementation group vs 143 in the pre-implementation group). Solid organ cancer was present in 77/295 patients while immunomodulatory treatments were noticed in 135/295. They were 35 ICU-AI in 29/143 patients in the standard-care group as compared with 10 ICU-AI in 9/151 patients in the post-implementation group (
p
< 0.001). In a multivariable Poisson regression model, MSD was independently associated with a decreased incidence of ICU-AI (incidence rate ratio = 0.39; 95%CI 0.20–0.87
p
= 0.008). There were 35/143 deaths in the standard-care group as compared with 22/151 in the post-implementation group (
p
= 0.046), this difference remained in a multivariable Cox model (HR = 0.58; 95CI 0.34–0.95
p
= 0.048).
Conclusion
In conclusion, MSD appeared to be associated with improved outcomes in critically ill immunocompromised patients.
Water treatment is crucial to improve the water quality and reduce diarrheal and chronological diseases caused by excessive discharge of organic dyes and other waste. The development and expansion of ...efficient catalysts for the degradation and sterilization of organic dyes has attracted widespread attention. Herein, we report an example of a porphyrin-based two-dimensional layered metal–organic framework (MOF) (2DZnTcpp) and its efficient sono-/photocatalytic degradation of organic dyes and bactericidal activity. The dislocated layers effectively avoid close π–π stacking and provide a porous space for oxygen/water/dye contact. The introduction of Zn ions increases the spin orbital coupling through the heavy atom effect and promotes the intersystem crossing process for singlet oxygen generation. The effective ligand-to-metal charge transfer and the excessive open Zn catalytic sites also facilitate water splitting for hydroxyl radical generation. These features together promote the reactive oxygen species (ROS) generation of 2DZnTcpp under light illumination or ultrasound sonication. It is worth noting that the 2DZnTcpp with a high specific surface area and porosity shows efficient sono-/photocatalytic degradation of organic dye waste. Moreover, 2DZnTcpp could also largely inactivate Escherichia coli under light irradiation (the light power of 1 sun) or ultrasound sonication for 30 min with efficiencies over 99.99999%. This work provides an approach for the design and synthesis of MOF-based sono-/photocatalysts used in the purification and treatment of textile wastewater and is committed to the establishment of a more efficient, fast, and environmentally friendly catalytic system.
Skin decontamination in cold weather temperatures might be challenging due to the aggravating circumstances. However, no information is available on the efficacy of commonly used procedures in winter ...conditions. Therefore, the efficacy of the reactive skin decontamination lotion (RSDL) and soapy water decontamination following skin exposure to the nerve agent VX was evaluated at three ambient air temperatures (−5°C, −15°C and room temperature). Experiments were performed in vitro using human dermatomed skin. The ability of RSDL to degrade VX at the three different air temperatures was separately evaluated. The ambient air temperature in experiments without decontamination did not influence the penetration rate of VX through skin. RSDL decontamination was highly efficient in removing VX from skin when performed in all three ambient temperatures, despite the slower agent degradation rate of VX at the lower temperatures. Decontamination with soapy water at RT resulted in an increased skin penetration of VX compared with the control without decontamination; however, in colder temperatures the VX skin penetration was similar to the corresponding control without decontamination. At RT, dry removal prior to washing with soapy water did not improve decontamination of VX compared with washing solely with soapy water. This study demonstrated high efficacy of RSDL decontamination following skin exposure to VX also at cold temperatures. The previously reported ‘wash‐in’ effect of soapy water on VX skin penetration was reduced at cold temperatures. Altogether, this study found a scientific basis to establish guidelines for skin decontamination of chemical casualties at cold weather temperatures.
Skin decontamination is crucial when managing individuals exposed to low volatile nerve agents. However, no information is available on the efficacy of commonly used procedures in cold weather temperatures. In vitro human skin studies displayed high efficacy for RSDL decontamination following VX exposure in air temperatures between 20°C and −15°C. The ‘wash‐in’ effect of VX following soapy water decontamination observed in RT was reduced at cold temperatures. A scientific basis is established for skin decontamination guidelines in cold temperatures.
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.
The abrupt outbreak of the novel coronavirus disease 2019 and its rapid spread over many healthcare systems throughout the world has led to a shortage in personal protective equipment (PPE), which ...cannot be solved by reducing their use or by increasing production. It is thus necessary to promote PPE rational use, highlighting possible differences in terms of efficacy and promoting an effective technique to reuse them.
A literature search was performed on PubMed, Scopus, Cochrane database, and Google Scholar, and from the 25 top cited articles, 15 were selected for relevance and impact.
Most studies on previous respiratory virus epidemics to date suggest surgical masks are not inferior compared with N95 respirators in terms of protective efficacy among healthcare workers. Therefore, the use of N95 respirators should be limited to high-risk situations. Concerning respirator reuse, highly energetic, short-wave, ultraviolet germicidal irradiation (UVGI) at 254 nm was determined to decontaminate N95 respirators from viral respiratory agents, but UVGI requires careful consideration of the type of respirator and of the biologic target.
Rational use and successful reuse of respirators can help in the shortage of PPE during a pandemic. Further studies testing UVGI and other decontamination techniques are an unmet need. The definitive answer to pandemic issues can be found in artificial intelligence and deep learning. These groundbreaking modalities could help in identifying high-risk patients and in suggesting appropriate types and use of PPE.
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Fresh produce is frequently associated with outbreaks of foodborne diseases; thus, there is a need to develop effective intervention technologies and antimicrobial treatments to improve the microbial ...safety of fresh produce. Washing with chemical sanitizers, commonly used by the industry, is limited in its effectiveness and is viewed as a possible cross-contamination opportunity. This review discuses the advanced oxidation process (AOP), which involves generating highly reactive hydroxyl radicals to inactivate human pathogens. Ionizing irradiation, ultraviolet (UV) light, and cold plasma can be regarded as AOP; however, AOPs employing combinations of UV, H2O2, cold plasma, and ozone may be more promising because higher amounts of hydroxyl radicals are produced in comparison to the individual treatments and the combinative AOPs may be more consumer friendly than ionizing irradiation. When applied as a gaseous/aerosolized treatment, AOPs may have advantages over immersion treatments, considering the reactivity of hydroxyl radicals and presence of organic materials in wash water. Gaseous/aerosolized AOPs achieve up to 5 log reductions of pathogenic bacteria on fresh produce compared to reductions of 1–2 logs with aqueous sanitizers. Further research needs to be conducted on specific AOPs before being considered for commercialization, such as reduced formation of undesirable chemical byproducts, impact on quality, and scaled up studies.
A single spray application of a continuously active disinfectant on portable equipment resulted in significant reductions in aerobic colony counts over 7 days and in recovery of Staphylococcus aureus ...and enterococci: 3 of 93 cultures (3%) versus 11 of 97 (11%) and 20 of 97 (21%) in quaternary ammonium disinfectant and untreated control groups, respectively.
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