Use of selective gut decontamination in critically ill children: PICnIC a pilot RCT and mixed-methods study.

Background: Healthcare-associated infections are a major cause of morbidity and mortality in critically ill children. In adults, data suggest the use of selective decontamination of the digestive tract may reduce the incidence of healthcare-associated infections. Selective decontamination of the digestive tract has not been evaluated in the paediatric intensive care unit population. Objectives: To determine the feasibility of conducting a multicentre, cluster-randomised controlled trial in critically ill children comparing selective decontamination of the digestive tract with standard infection control. Design: Parallel-group pilot cluster-randomised controlled trial with an integrated mixed-methods study. Setting: Six paediatric intensive care units in England. Participants: Children (> 37 weeks corrected gestational age, up to 16 years) requiring mechanical ventilation expected to last for at least 48 hours were eligible for the PICnIC pilot cluster-randomised controlled trial. During the ecology periods, all children admitted to the paediatric intensive care units were eligible. Parents/legal guardians of recruited patients and healthcare professionals working in paediatric intensive care units were eligible for inclusion in the mixed-methods study. Interventions: The interventions in the PICnIC pilot cluster-randomised controlled trial included administration of selective decontamination of the digestive tract as oro-pharyngeal paste and as a suspension given by enteric tube during the period of mechanical ventilation. Main outcome measures: The decision as to whether a definitive cluster-randomised controlled trial is feasible is based on multiple outcomes, including (but not limited to): (1) willingness and ability to recruit eligible patients; (2) adherence to the selective decontamination of the digestive tract intervention; (3) acceptability of the definitive cluster-randomised controlled trial; (4) estimation of recruitment rate; and (5) understanding of potential clinical and ecological outcome measures. Results: A total of 368 children (85% of all those who were eligible) were enrolled in the PICnIC pilot cluster-randomised controlled trial across six paediatric intensive care units: 207 in the baseline phase (Period One) and 161 in the intervention period (Period Two). In sites delivering selective decontamination of the digestive tract, the majority (98%) of children received at least one dose of selective decontamination of the digestive tract, and of these, 68% commenced within the first 6 hours. Consent for the collection of additional swabs was low (44%), though data completeness for potential outcomes, including microbiology data from routine clinical swab testing, was excellent. Recruited children were representative of the wider paediatric intensive care unit population. Overall, 3.6 children/site/week were recruited compared with the potential recruitment rate for a definitive cluster-randomised controlled trial of 3 children/site/week, based on data from all UK paediatric intensive care units. The proposed trial, including consent and selective decontamination of the digestive tract, was acceptable to parents and staff with adaptations, including training to improve consent and communication, and adaptations to the administration protocol for the paste and ecology monitoring. Clinical outcomes that were considered important included duration of organ failure and hospital stay, healthcare-acquired infections and survival. Limitations: The delivery of the pilot cluster-randomised controlled trial was disrupted by the COVID-19 pandemic, which led to slow set-up of sites, and a lack of face-to face training. Conclusions: PICnIC's findings indicate that a definitive cluster-randomised controlled trial in selective decontamination of the digestive tract in paediatric intensive care units is feasible with the inclusion modifications, which would need to be included in a definitive cluster-randomised controlled trial to ensure that the efficiency of trial processes is maximised. Future work: A definitive trial that incorporates the protocol adaptations and outcomes arising from this study is feasible and should be conducted. Trial registration: This trial is registered as ISRCTN40310490. Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 16/152/01) and is published in full in Health Technology Assessment; Vol. 28, No. 8. See the NIHR Funding and Awards website for further award information.

Each year, around 20,000 critically ill children are admitted to paediatric intensive care units in the UK. These children are at a higher risk of healthcare-associated infections, one of the main sources of which is the large number of bacteria in the digestive tract. Spread of bacteria from the digestive tract into other organs, such as the lung (causing ventilator-associated pneumonia) or bloodstream (causing sepsis), can be life-threatening. The risk is highest in those children whose illness is so severe that they require prolonged mechanical ventilation. Stopping the growth of bacteria in the digestive tract (called selective decontamination of the digestive tract) has been shown in adults to reduce the number of hospital-acquired infections. However, there have been no trials in children. We wanted to assess how practical and acceptable such a trial would be comparing standard infection control to selective decontamination of the digestive tract-enhanced infection control and monitoring how each intervention affected antimicrobial resistance. We undertook a pilot study to examine whether clinicians could identify eligible children, enrol them in the study and follow study procedures during the course of paediatric intensive care unit admission. Alongside this, we interviewed parents and clinicians to get their views on the proposed trial. Six hospitals recruited 559 patients over a period of roughly 7 months. Hospitals were randomly allocated to continue with the standard infection control procedure or to give selective decontamination of the digestive tract. Overall, recruitment was higher than expected. Alongside this, we examined the views of patients, caregivers and healthcare professionals to assess their views on whether a trial should be carried out to see if selective decontamination of the digestive tract should become part of the infection control regime for children most at risk of hospital-acquired infection in the paediatric intensive care unit. Overall results suggest that a larger PICnIC trial incorporating patient stakeholder and clinical staff feedback on design and outcomes is feasible and that it is appropriate to conduct a trial into the effectiveness of selective decontamination of the digestive tract administration to minimise hospital-acquired infections.

Anatomical three-dimensional model with peri-implant defect for in vitro assessment of dental implant decontamination.

OBJECTIVES: Access to the implant surface plays a significant role in effective mechanical biofilm removal in peri-implantitis treatment. Mechanical decontamination may also alter the surface topography of the implant, potentially increasing susceptibility to bacterial recolonization. This in vitro study aimed to evaluate a newly developed, anatomically realistic, and adaptable three-dimensional (3D)printed model with a peri-implant bone defect to evaluate the accessibility and changes of dental implant surfaces after mechanical decontamination treatment. MATERIAL AND METHODS: A split model of an advanced peri-implant bone defect was prepared using 3D printing. The function of the model was tested by mechanical decontamination of the exposed surface of dental implants (Standard Implant Straumann AG) coated with a thin layer of colored occlusion spray. Two different instruments for mechanical decontamination were used. Following decontamination, the implants were removed from the split model and photographed. Image analysis and fluorescence spectroscopy were used to quantify the remaining occlusion spray both in terms of area and total amount, while scanning electron microscopy and optical profilometry were used to analyze alteration in the implant surface morphology. RESULTS: The 3D model allowed easy placement and removal of the dental implants without disturbing the implant surfaces. Qualitative and quantitative assessment of removal of the occlusion spray revealed differences in the mechanism of action and access to the implant surface between tested instruments. The model permitted surface topography analysis following the decontamination procedure. CONCLUSION: The developed 3D model allowed a realistic simulation of decontamination of implant surfaces with colored occlusion spray in an advanced peri-implant defect. 3D printing allows easy adaptation of the model in terms of the shape and location of the defect. The model presents a valuable tool for in vitro investigation of the accessibility and changes of the implant surface after mechanical and chemical decontamination.

Recent advances in eco-friendly technology for decontamination of pulp and paper mill industrial effluent: a review.

The economic development of a country directly depends upon industries. But this economic development should not be at the cost of our natural environment. A substantial amount of water is spent during paper production, creating water scarcity and generating wastewater. Therefore, the Pollution Control Board classifies this industry into red category. Water is used in different papermaking stages such as debarking, pulping or bleaching, washing, and finishing. The wastewater thus generated contains lignin and xenobiotic compounds such as resin acids, chlorinated lignin, phenols, furans, dioxins, chlorophenols, adsorbable organic halogens (AOX), extractable organic halogens (EOCs), polychlorinated biphenyls, plasticizers, and polychlorinated dibenzodioxins. Nowadays, several microorganisms are used in the detoxification of these hazardous effluents. Researchers have found that microbial degradation is the most promising treatment method to remove high biological oxygen demand (BOD) and chemical oxygen demand (COD) from wastewater. Microorganisms also remove AOX toxicity, chlorinated compounds, suspended solids, color, lignin, derivatives, etc. from the pulp and paper mill effluents. But in the current scenario, mill effluents are known to deteriorate the environment and therefore it is highly desirable to deploy advanced technologies for effluent treatment. This review summarizes the eco-friendly advanced treatment technologies for effluents generated from pulp and paper mills.

Assessing the potential of portable X-ray fluorescence (XRF) as a rapid, onsite screening tool in the assessment of cadmium surface decontamination effectiveness.

Portable X-ray fluorescence has successfully been used to effectively evaluate occupational exposure to airborne and surface metal contaminants nondestructively. Traditional methods of assessing metal surface contamination involve the costly, time-consuming collection and laboratory analysis of wipe samples, making portable X-ray fluorescence an attractive alternative method for screening worksites by reducing delays in risk assessment decision-making. Existing research into this use of portable X-ray fluorescence has primarily been centered on the analysis of airborne and surface lead contamination. The extant literature is sparse on the use of portable X-ray fluorescence with other metals for surface contamination with respect to occupational exposure. The present study evaluated the use of portable X-ray fluorescence in the screening of cadmium surface contamination to determine if the effectiveness of decontamination measures can be ascertained by this technique. Wipe samples were collected and screened with portable X-ray fluorescence before being sent to the laboratory for definitive analysis to assess the correlation between portable X-ray fluorescence readings in percent mass with laboratory results in µg/ft2. Portable X-ray fluorescence readings demonstrated a strong linear correlation with laboratory results, as indicated by the R2 value of 0.993. Therefore, this technique may be further developed and deployed as a screening tool for wipe samples used for evaluating contamination and decontamination of metal-contaminated areas.

Dissipation kinetics, decontamination, consumer risk assessment and monitoring of flonicamid and imidacloprid residues in capsicum under open field and polyhouse condition.

Liquid chromatography mass spectrometry (LC-MS)-based detection of flonicamid, imidacloprid and 6-chloronicotinic acid residues was validated and analysed in capsicum fruit, processed products and soil. The standard concentrations (0.0025 to 0.25 µg mL-1) of insecticides had a good linear curve (r2>0.99). Limit of detection and limit of quantification values were 0.0025 and 0.01 mg kg-1, respectively. The accuracy (80.53 to 100.33 %) of capsicum matrices and soil (89.41 to 100.52 %) and precision (RSD <10%) were established. Dissipation of imidacloprid (20 and 40 g a.i. ha-1) and flonicamid (75 and 150 g a.i. ha-1) at single (X) and double dose (2X) was studied under open field and polyhouse conditions. Under open field conditions, the flonicamid and imidacloprid residues persisted with half-life of 1.98, 2.90 days (X) and 2.80, 3.14 (2X) days, respectively. While under polyhouse conditions, the flonicamid and imidacloprid residues persisted with a half-life of 2.84, 3.66 (X) and 3.24, 3.97 (2X) days, respectively. The metabolite, 6-CNA, was not detected in any samples under open field and polyhouse condition. Among decontamination treatments, cooking in boiling water for 10 minutes reduced 78 to 81.60 percent of imidacloprid and flonicamid residues in both doses. The estimated dietary risk assessment of imidacloprid and flonicamid residues (RQ <1) indicated that the risk is within the acceptable limit. In farmgate capsicum samples, residues of flonicamid (7 samples) and imidacloprid (11 samples) were detected. Market samples of capsicum products (powder, flakes and sauce) were not detected with residues of selected insecticides.

Cost-effectiveness of selective decontamination of the digestive tract to decrease infectious complications in colorectal cancer surgery: An analysis of the SELECT trial.

INTRODUCTION: Selective decontamination of the digestive tract (SDD) is effective in reducing infectious complications in elective colorectal cancer (CRC) surgery. However, it is unclear whether SDD is cost-effective compared to standard antibiotic prophylaxis. MATERIAL & METHODS: Economic evaluation alongside multicenter randomized controlled trial, the SELECT-trial, from a healthcare perspective. Patients included underwent elective surgery for non-metastatic CRC. The intervention group received oral non-absorbable colistin, tobramycin and amphotericin B (SDD) next to standard antibiotic prophylaxis. Both groups received a single shot intravenous cefazolin and metronidazole preoperatively as standard prophylaxis. Occurrence of postoperative infectious complication in the first 30 postoperative days was extracted from medical records, Quality-Adjusted Life-Years (QALYs) based on the ED-5D-3L, and healthcare costs collected from the hospital's financial administration. RESULTS: Of the 455 patients, 228 were randomly assigned to intervention group and 227 patients to the control group. SDD significantly reduced the number of infectious complications compared to control (difference = -0.13, 95 % CI -0.05 to -0.20). No difference was found for QALYs (difference = 0.002, 95 % CI -0.002 to 0.005). Healthcare costs were statistically significantly lower in the intervention group (difference = -€1258, 95 % CI -2751 to -166). The ICER was -9872 €/infectious complication prevented and -820,380 €/QALY gained. For all willingness-to-pay thresholds, the probability that prophylactic SDD was cost-effective compared to standard prophylactic practice alone was 1.0. CONCLUSION: The addition of SDD to the standard preoperative intravenous antibiotic prophylaxis is cost-effective compared to standard prophylactic practice from a healthcare perspective and should be considered as the standard of care.

Extraction and decontamination of microplastics from high organic matter soils: A simple, cost-saving and high efficient method.

This article introduces a simple, cost-saving and high efficient for the extraction and separation of microplastics (MPs) from soil with a high organic matter (SOM) content. In this study, MP with particle sizes of 154-600 µm of polyethylene (PE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC) and polyethylene terephthalate (PET) were artificially added into the five Mollisols with the high SOM. Three flotation solutions were used to extract these MPs from soils, and four digestion solutions were used to digest the SOM. As well, their destruction effects on MPs were also examined. The results showed that the flotation recovery rates of PE, PP, PS, PVC and PET were 96.1%-99.0% by ZnCl2 solution, while were 102.0%-107.2% by rapeseed oil, were 100.0%-104.7% by soybean oil. The digestion rate of SOM was 89.3% by H2SO4:H2O2 (1:40, v:v) at 70 °C for 48 h, and this was higher than by H2O2 (30%), NaOH and Fenton's reagent. However, the digestion rate of PE, PP, PS, PVC and PET were 0.0%-0.54% by H2SO4:H2O2 (1:40, v:v), and this was lower than by H2O2 (30%), NaOH and Fenton's reagent. As well, the factors influencing on MP extraction was also discussed. Generally, the best flotation solution was ZnCl2 (ρ > 1.6 g cm-3) and the best digestion method was H2SO4:H2O2 (1:40, v:v) at 70 °C for 48 h. The optimal extraction and digestion method were verified by the known concentrations of MPs (recovery rate of MPs was 95.7-101.7%), and this method was also used to extract MPs from long-term mulching vegetable fields in Mollisols of Northeast China.

Analysis of cyantraniliprole residues in beetroot and beet top using LC-MS/MS, dietary exposure assessment, and evaluation of decontamination techniques.

A modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) method was standardized for the analysis of cyantraniliprole residues in beetroot and beet top (Beta vulgaris ssp. vulgaris L.) using liquid chromatography-mass spectrometry/mass spectrometry. Samples were extracted with acetonitrile and cleaned up by dispersive solid phase extraction. Acceptable recovery of 84.74%-104.24% for beetroot and 80.19%-118.55% for beet top matrix was achieved at fortification levels ranging from 0.02 to 0.025 µg g-1 , with relative standard deviation <20% that signified the application of the method for detecting cyantraniliprole residues. A field experiment was conducted to determine the half-life and preharvest interval for cyantraniliprole residues in beetroot and beet top. The half-life obtained was 1.86-2.7 days for beetroot and 3.65-5.33 days for beet top. The preharvest interval calculated was 9.12-12.90 and 22.12-37.98 days for beetroot and top, respectively. The dietary exposure assessment at studied doses found cyantraniliprole residues below acceptable daily contact limits. Among different decontamination techniques evaluated, peeling + tap water washing resulted in a higher reduction of residues while cooking and juicing resulted in moderate removal of residues.

Assessment of calcium hypochlorite for Bacillus anthracis spore surface's decontamination.

Contamination with microorganisms occurs in laboratories but is also of high concern in the context of bioterrorism. Decontamination is a cornerstone that promotes good laboratory practices and occupational health and safety. Among the most resistant structures formed by microorganisms are spores, produced notably by Clostridium and Bacillus species. Here, we compared six products containing four different molecules (hydrogen peroxide, peracetic acid, sodium and calcium hypochlorite) on B. anthracis Sterne spores. We first selected the most efficient product based on its activity against spore suspensions using French and European standards. Four products showed sporicidal activity, of which only two did so in a time frame consistent with good laboratory practices. Then, we tested one of these two products under laboratory conditions on fully virulent B. anthracis spores, during common use and after contamination through a spill of a highly concentrated spore suspension. We, thus, robustly validated a decontaminant based on calcium hypochlorite not only on its ability to kill spores but also on its effectiveness under laboratory conditions. At the end, we were able to assure a complete disinfection in 1 min after spillover and in 2 min for common use.

Decontamination of high-touch environmental surfaces (HITES) by wiping: quantitative assessment of a carrier platform simulating pathogen removal, inactivation and transfer in the field.

We report here a carrier platform (Teflon; 30.0 × 60.0 × 0.9 cm) and a carrier retrieval device to assess pathogen decontamination of high-touch environmental surfaces (HITES) by wiping. Each one of the nine metallic disks (1 cm diameter and 0.7 mm thick) received 10 µL of the microbial suspension in a soil load, the inocula dried and the platform then wiped with a piece of fabric presoaked in a control or disinfectant fluid; the used wipe was immediately applied on a second platform with sterile disks to assess microbial transfer. Each test and control disk from a given platform was separately and simultaneously retrieved into 10 mL of an eluent/neutralizer for assays at the end of the contact time (total of 5 min, starting from the beginning of the wiping). Staphylococcus aureus and Acinetobacter baumannii were used as representative HITES-borne pathogens. The wipes tested separately contained 0.26% of a quaternary ammonium compound (Product A), and 250 ppm sodium hypochlorite at neutral pH (Product B). The control fabric (Product C) was dampened with a buffer containing a detergent. Product A achieved a >4 log10 (>99.99%) reduction in the viability of the bacteria on wiping with a barely detectable level of transfer of CFUs to clean disks. Product B achieved a >2 log10 (>99.00%) reduction in the viability of the test microbes while transferring a higher level of CFUs as compared to Product A. With Product C, there was a <1 log10 (<86.2%) reduction in the viability of the test microbes while transferring >1% of the contamination.

Simultaneous Monitoring and Decontamination of Pesticide Residues in Phytomedicine-Enriched Betel Leaf Utilizing QuEChERS-GC-MS/MS Technology to Safeguard Public Health.

BACKGROUND: The presence of undesirable substances, including pesticides (xenobiotics) in betel leaf (Piper betel), is a great concern for consumers because it is chewed and consumed directly. To protect the consumer's health, a modified QuEChERS method for monitoring purposes and subsequent decontamination process has been developed. OBJECTIVE: The goal of this work was to establish a multi-residue analytical method for monitoring nonpermitted organophosphorus pesticide residues in betel leaf, as well as cost-effective cleaning strategies. METHOD: The homogenized 15 g samples (20 betel leaf samples collected in West Bengal, India) were extracted with a modified QuEChERS method using acetonitrile, reconstituted to acetone, and finally analyzed by GC-MS/MS. Possible decontamination techniques (such as tap water washing, 2% saltwater washing, and lukewarm water washing) were evaluated. RESULTS: The limit of detection ranged from 0.003 to 0.005 mg/kg, and limit of quantification was 0.01 mg/kg. Recoveries ranged from 80 to 120% with RSDr 9%. One sample was found to contain three pesticides 4 to 7 times higher than MRLs. Suggested decontamination methods allowed reducing toxic traces below European limits. CONCLUSIONS: The suggested approach is useful for determining pesticide residues in betel leaves quickly. Traditional techniques of processing betel leaves may reduce pesticide residues below regulatory limits. HIGHLIGHTS: A multi-residue method and decontamination of pesticides in betel leaf using QuEChERS-GC-MS/MS technology with satisfactory method performance was achieved. Domestic decontamination techniques have a high efficacy in reducing pesticide residues from betel leaves, making them safe for human consumption.

Sensitive microscopic quantification of surface-bound prion infectivity for the assessment of surgical instrument decontamination procedures.

BACKGROUND: Pathogenic prions (PrPSc) are amyloid-rich hydrophobic proteins which bind avidly to surgical surfaces and represent some of the most difficult targets during the reprocessing of reusable surgical instruments. In-vitro methods to amplify and detect the presence of otherwise undetectable prion contamination are available, but they do not measure associated infectivity. Most of these methods rely on the use of proteinase K, however this can lead to the loss of a substantial portion of PrPSc, potentially producing false negatives. AIM: To develop a sensitive in-situ method without proteinase treatment for the dynamic quantification of amyloid accumulation in N2a #58 cells following 22L-prion infection from infected tissues and spiked stainless-steel surfaces. METHODS: We spiked cultures of N2a #58 cells with the 22L prion strain in solution or dried on stainless-steel wires and directly measured the accumulation of prion amyloid aggregates over several passages using highly sensitive fluorescence microscopy. FINDINGS: We demonstrated a 10-log dynamic range using our method to test residual prion infectivity, that was validated to show variable decontamination efficacy against prions from commercially available cleaning chemistries. CONCLUSIONS: The new cell-based infectivity method presented here avoids partial or possibly total proteinase K digestion of PrPSc in samples for greater sensitivity, in addition to low cost, no ethical concerns, and adaptability to detect different prion strains. This method can be used to test cleaning chemistries' efficacy with greater sensitivity than measuring total residual proteins, which may not correlate with residual prion infectivity.

Effectiveness of a low-cost UVGI chamber for decontaminating filtering facepiece respirators to extend reuse.

In emergencies like the COVID-19 pandemic, the reuse or reprocessing of filtering facepiece respirators (FFRs) may be required to mitigate exposure risk. Research gap: Only a few studies evaluated decontamination effectiveness against SARS-CoV-2 that are practical for low-resource settings. This study aimed to determine the effectiveness of a relatively inexpensive ultraviolet germicidal irradiation chamber to decontaminate FFRs contaminated with SARS-CoV-2. A custom-designed UVGI chamber was constructed to determine the ability to decontaminate seven FFR models including N95s, KN95, and FFP2s inoculated with SARS-CoV-2. Vflex was excluded due to design folds/pleats and UVGI shadowing inside the chamber. Structural and functional integrity tolerated by each FFR model on repeated decontamination cycles was assessed. Twenty-seven participants were fit-tested over 30 cycles for each model and passed if the fit factor was ≥100. Of the FFR models included for testing, only the KN95 model failed filtration. The 3M™ 3M 1860 and Halyard™ duckbill 46727 (formerly Kimberly Clark) models performed better on fit testing than other models for both pre-and-post decontaminations. Fewer participants (0.3 and 0.7%, respectively) passed fit testing for Makrite 9500 N95 and Greenline 5200 FFP2 and only two for the KN95 model post decontamination. Fit testing appeared to be more affected by donning & doffing, as some passed with adjustment and repeat fit testing. A ≥ 3 log reduction of SARS-CoV-2 was achieved for worn-in FFRs namely Greenline 5200 FFP2. Conclusion: The study showed that not all FFRs tested could withstand 30 cycles of UVGI decontamination without diminishing filtration efficiency or facial fit. In addition, SARS-CoV-2 log reduction varied across the FFRs, implying that the decontamination efficacy largely depends on the decontamination protocol and selection of FFRs. We demonstrated the effectiveness of a low-cost and scalable decontamination method for SARS-CoV-2 and the effect on fit testing using people instead of manikins. It is recognized that extensive experimental evidence for the reuse of decontaminated FFRs is lacking, and thus this study would be relevant and of interest in crisis-capacity settings, particularly in low-resource facilities.

Assessment and clinical management of internal contamination.

Internal contamination by radionuclides may occur through inhalation, ingestion and absorption through the skin or subcutaneous tissue. The clinical management of internalized radionuclides requires the integration of clinical signs and symptoms with dose estimates in biological tissues obtained from the face, nose, sputum, urine, faeces and/or skin. The assessment of ingested radionuclides includes bioassays of urine and faeces, and if available, whole body counting for radionuclides that emit penetrating x-rays or gamma-rays. An estimate of intake dose may be made at the time of initial patient evaluation by measuring radioactivity, converting counts/minute to depositions/minute with a specific gamma-ray constant, and comparing the amount to its annual limit on intake, clinical decision guide or derived reference level. Since nobody dies from internal contamination per se, medically unstable patients should be stabilized before addressing internal contamination. Whenever possible, internal contaminants should be physically removed as soon as possible after exposure. For inhaled internal contaminants, radionuclide-specific therapy may include the administration of an ion exchange resin (i.e. Prussian blue, PB) or chelating agent (i.e. diethylenetriamine pentaacetate, DTPA, that binds toradioactiveplutonium, americium, and curium), or the physical removal of insoluble particles with a high activity radionuclide (192Ir,90Sr,210Po) by bronchioalveolar lavage. Decorporation with PB, DTPA and other agents is used to enhance excretion. The treatment of wounds contaminated with an actinide includes gentle irrigation, surgical excision of contaminated tissue and DTPA. The averted dose (i.e. the total effective dose averted by therapy) may be calculated for each exposure route.

Ferrous Industrial Wastes-Valuable Resources for Water and Wastewater Decontamination.

Ferrous waste by-products from the metallurgical industry have a high potential for valorization in the context of the circular economy, and can be converted to value-added products used in environmental remediation. This research reviews the latest data available in the literature with a focus on: (i) sources from which these types of iron-based wastes originate; (ii) the types of ferrous compounds that result from different industries; (iii) the different methods (with respect to the circular economy) used to convert them into products applied in water and wastewater decontamination; (iv) the harmful effects ferrous wastes can have on the environment and human health; and (v) the future perspectives for these types of waste.

Assessment of a novel, easy-to-implement, aerosolized H2O2 decontamination method for single-use filtering facepiece respirators in case of shortage.

The COVID-19 pandemic has affected the world and caused a supply shortage of personal protection equipment, especially filtering facepiece respirators (FFP). This has increased the risk of many healthcare workers contracting SARS-CoV-2. Various strategies have been assessed to tackle these supply issues. In critical shortage scenarios, reusing single-use-designed respirators may be required. Thus, an easily applicable and reliable FFP2 (or alike) respirator decontamination method, allowing safe re-use of FFP2 respirators by healthcare personnel, has been developed and is presented in this study. A potent and gentle aerosolized hydrogen peroxide (12% wt) method was applied over 4 hr to decontaminate various brands of FFP2 respirators within a small common room, followed by adequate aeration and storage overnight. The microbial efficacy was tested on unused respirator pieces using spores of Geobacillus stearothermophilus. Further, decontamination effectiveness was tested on used respirators after one 12-hr shift by swabbing before and after the decontamination. The effects of up to ten decontamination cycles on the respirators' functionality were evaluated using material properties, the structural integrity of the respirators, and fit tests with subjects. The suggested H2O2 decontamination procedure was proven to be (a) sufficiently potent (no microbial recovery, total inactivation of biological indicators as well as spore inoculum on critical respirator surfaces), (b) gentle as no significant damage to the respirator structural integrity and acceptable fit factors were observed, and (c) safe as no H2O2 residue were detected after the defined aeration and storage. Thus, this easy-to-implement and scalable method could overcome another severe respirator shortage, providing enough flexibility to draft safe, effective, and logistically simple crisis plans. However, as highlighted in this study, due to the wealth of design and material used in different models and brands of respirators, the decontamination process should be validated for each FFP respirator model before its field implementation.

Efficacy of hydrogen peroxide wipes for decontamination of AZD1222 adenovirus COVID-19 vaccine strain on pharmaceutical industry materials.

This study aimed to evaluate the performance of accelerated hydrogen peroxide® wipes (HPW) for decontamination of the chimpanzee adenovirus AZD1222 vaccine strain used in the production of recombinant COVID-19 vaccine in a pharmaceutical industry. Two matrices were tested on stainless-steel (SS) and low-density-polyethylene (LDP) surfaces: formulated recombinant COVID-19 vaccine (FCV) and active pharmaceutical ingredient (API). The samples were spiked, dried and the initial inoculum, possible residue effect (RE) and titre reduction after disinfection with HPW were determined. No RE was observed. The disinfection procedure with HPW resulted in complete decontamination the of AZD1222 adenovirus strain in FCV (≥7·46 and ≥7·49 log10 infectious unit [IFU] ml-1 for SS and LDP carriers respectively) and API (≥8·79 and ≥8·78 log10 IFU ml-1 for SS and LDP carriers respectively). In conclusion, virucidal activity of HPW was satisfactory against the AZD1222 adenovirus strain and can be a good option for disinfection processes of SS and LPD surfaces in pharmaceutical industry facilities during recombinant COVID-19 vaccine production. This procedure is simple and can be also applied on safety unit cabins and sampling bags made of LDP as well.

Assessment of Surface Disinfection Effectiveness of Decontamination System COUNTERFOG® SDR-F05A+ Against Bacteriophage ɸ29.

The experience of COVID19 pandemic has demonstrated the real concern of biological agents dispersed in the air and surfaces environments. Therefore, the need of a fast and large-scale disinfection method has arisen for prevention of contagion. COUNTERFOG® is an innovative technology developed for large-scale decontamination of air and surfaces. The objective of this study is to assess experimentally the effectiveness of COUNTERFOG® in disinfecting viral-contaminated surfaces. We also aim to measure the necessary time to disinfect said surfaces. Stainless steel surfaces were contaminated with bacteriophage φ29 and disinfected using COUNTERFOG® SDR-F05A+, which uses a sodium hypochlorite solution at different concentrations and for different exposure times. A log reduction over 6 logs of virus titer is obtained in 1 min with 1.2% sodium hypochlorite when the application is direct; while at a radial distance of 5 cm from the point of application the disinfection reaches a reduction of 5.5 logs in 8 min. In the same way, a higher dilution of the sodium hypochlorite concentration (0.7% NaOCl) requires more exposure time (16 min) to obtain the same log reduction (> 6 logs). COUNTERFOG® creates, in a short time and at a distance of 2 m from the point of application, a thin layer of disinfectant that covers the surfaces. The selection of the concentration and exposure time is critical for the efficacy of disinfection. These tests demonstrate that a concentration between 0.7- 1.2% sodium hypochlorite is enough for a fast and efficient ɸ29 phage inactivation. The fact that ɸ29 phage is more resistant to disinfection than SARS-CoV-2 sustains this disinfection procedure.

Returning Home after Decontamination? Applying the Protective Action Decision Model to a Nuclear Accident Scenario.

Studies of the aftermath of nuclear power plant accidents show that affected citizens assess higher risks and adopt more risk-avoidant behaviors than authorities expect. This results in differences between the planned recovery and actual outcomes. Based on this knowledge, this study examined the factors that affect citizens' preference to continue living in a decontaminated area. Testing the key aspects of the protective action decision model (PADM), this study analyzed Swedish survey data (N = 2291) regarding such an accident scenario. Several aspects of the PADM, from the layperson's view of threats and protective actions, to stakeholders and situational factors, were strongly supported. The most influential variables affecting settlement choices are perceptions of radiation risk, perceptions of decontamination effectiveness, government information, living with certain restrictions, and attachment to an area because of one's work. A novel contribution of this study is that it ranked the significance of such effects on behavioral intentions in an emergency scenario. Regarding the policy recommendations, this study concluded that a recovery program must facilitate most aspects of people's lives and provide trustworthy information on decontamination efficiency. As some people will avoid potential health risks and leave a decontaminated area, planning to implement one solution for everyone would likely not be optimal.

Decontamination Assessment of Nanofiber-based N95 Masks.

As the world battles with the outbreak of the novel coronavirus, it also prepares for future global pandemics that threaten our health, economy, and survivor. During the outbreak, it became evident that use of personal protective equipment (PPE), specially face masks, can significantly slow the otherwise uncontrolled spread of the virus. Nevertheless, the outbreak and its new variants have caused shortage of PPE in many regions of the world. In addition, waste management of the enormous economical and environmental footprint of single use PPE has proven to be a challenge. Therefore, this study advances the theme of decontaminating used masks. More specifically, the effect of various decontamination techniques on the integrity and functionality of nanofiber-based N95 masks (i.e. capable of at least filtering 95% of 0.3 µm aerosols) were examined. These techniques include 70% ethanol, bleaching, boiling, steaming, ironing as well as placement in autoclave, oven, and exposure to microwave (MW) and ultraviolet (UV) light. Herein, filtration efficiency (by Particle Filtration Efficiency equipment), general morphology, and microstructure of nanofibers (by Field Emission Scanning Electron microscopy) prior and after every decontamination technique were observed. The results suggest that decontamination of masks with 70% ethanol can lead to significant unfavorable changes in the microstructure and filtration efficiency (down to 57.33%) of the masks. In other techniques such as bleaching, boiling, steaming, ironing and placement in the oven, filtration efficiency dropped to only about 80% and in addition, some morphological changes in the nanofiber microstructure were seen. Expectedly, there was no significant reduction in filtration efficiency nor microstructural changes in the case of placement in autoclave and exposure to the UV light. It was concluded that, the latter methods are preferable to decontaminate nanofiber-based N95 masks.