Decontamination Capabilities Research Articles

Pseudomonas aeruginosa biofilm decontamination and removal by Ar/H2O cold atmospheric plasma in endoscope-like tubing

Abstract In medical device disinfection, removing bacteria and biofilms is challenging due to the poor penetration of detergents into the biofilm matrix. This is specifically true for endoscopes, which cannot be fully sterilized. This paper presents a new technique for decontaminating and removing P. aeruginosa biofilm from endoscope tubing using cold atmospheric plasma (CAP). The CAP is produced everywhere inside a contaminated tube under sustained Ar/H2O flow. The tube arrangement mimics the working channel environment of an endoscope, which is particularly difficult to sterilize. The discharge’s chemical activity was optimized by increasing the voltage without increasing the total power, which enhanced the production of hydroxyl radicals (OH) and hydrogen peroxide (H2O2). The disinfection treatment was tested on 24 h grown biofilm using the crystal violet assay for biofilm removal and the regrowth assay for bacterial decontamination. The treatments demonstrated effective decontamination capabilities at all treatment times with no bacterial regrowth. Etching of the biofilm sample by OH radicals was observed. After 30 min of treatment, only 18 ± 4% of biofilm remained on the surface, indicating near-complete biofilm removal and total absence of bacterial regrowth. This preliminary study demonstrates the effectiveness of using the direct contact of an Ar/H2O plasma to decontaminate and remove biofilm from complex shapes, such as flexible polytetraethylene tubes. It has the potential to enhance and shorten the disinfection of medical equipment, such as endoscopes.

Plasma-Functionalized Liquids for Decontamination of Viable Tissues: A Comparative Approach

Plasma-functionalized liquids (PFLs) are rich in chemical species, such as ozone, hydrogen peroxide, singlet oxygen, hydroxyl radical and nitrogen oxides, commonly referred to as reactive oxygen and nitrogen species (RONS). Therefore, manifold applications are being investigated for their use in medicine, agriculture, and the environment. Depending on the goal, a suitable plasma source concept for the generation of PFLs has to be determined because the plasma generation setup determines the composition of reactive species. This study investigates three PFL-generating plasma sources—two spark discharges and a flow dielectric barrier discharge (DBD) system—for their efficacy in eliminating microbial contaminants from tissue samples aiming to replace antibiotics in the rinsing process. The final goal is to use these tissues as a cell source for cell-based meat production in bioreactors and thereby completely avoid antibiotics. Initially, a physicochemical characterization was conducted to better understand the decontamination capabilities of PFLs and their potential impact on tissue viability. The results indicate that the flow DBD system demonstrated the highest antimicrobial efficacy due to its elevated reactive species output and the possibility of direct treatment of tissues while tissue integrity remained. Achieving a balance between effective large-scale decontamination and the biocompatibility of PFLs remains a critical challenge.

Exploration of self-crosslinking induced surface modification using APTES on the PA RO membrane for excellent anti-fouling performance

The physicochemical properties of the polyamide reverse osmosis (PA RO) membrane surface play a crucial role in membrane fouling. In this work, a silicon-based material, γ-Aminopropyl triethoxysilane (APTES), was incorporated onto the PA membrane surface by self-crosslinking induced surface modification to improve its antifouling properties. FTIR and XPS analyses reveal that APTES primarily bonded to the pristine PA membrane via amidation between –NH2 groups in APTES and residual –COCl groups on the membrane surface, and then combined with each other to form Si–O–Si groups (even Si–O–Si networks). The incorporation of APTES reduces the membrane surface energy and roughness, and the surface potential of the membranes can be adjusted by varying the APTES addition. Meanwhile, the pure water permeance of the APTES-PA membrane reached ~3.77 LMH/bar while maintaining a NaCl rejection of ~98.65%. Additionally, although the negative charge of the APTES-PA (M0.15) membrane increases, the antifouling against electropositive small molecular foulants is enhanced, mainly due to the low-surface-energy of the APTES-modified layer. Furthermore, the stability of the APTES-modified layer in the presence of electronegative small molecular foulants with strong decontamination capabilities can be reinforced by a simple high-temperature heat treatment. Broadly speaking, surface modification of the PA RO membrane by APTES combining grafting with self-crosslinking induced method is beneficial for its anti-fouling and reuse.

Peroxymonosulfate activation by superparamagnetic mixed-valent Cu/N-(L-cysteine)-O-(carboxymethyl)chitosan/cobalt ferrate-rice hull hybrid nanocomposite for efficient degradation of naproxen: Synergetic adsorption-catalysis, kinetics, pathway, and relevant mechanism

Naproxen (NPX) as an emerging anthropogenic contaminant was detected in many water sources, which can pose a serious threat to the environment and human health. Peroxymonosulfate (PMS) decomposed by Cu(I) has been considered an effective activation method to produce reactive species. However, this decontamination process is restricted by the slow transformation of Cu(II)/Cu(I) by PMS. Herein, new N-(L-cysteine/triazine)-O-(carboxymethyl)-chitosan/cobalt ferrate-rice hull hybrid biocomposite was constructed to anchor the mixed-valent Cu(I)-Cu (II) (CuI, II-CCCF) for removing pharmaceutical pollutants (i.e., naproxen, ciprofloxacin, tetracycline, levofloxacin, and paracetamol). The structural, morphological, and catalytic properties of the CuI,II-CCCF have been fully identified by a series of physicochemical characterizations. Results demonstrated that the multifunctional, hydrophilic character, and negative ζ-potential of the activator, accelerating the redox cycle of Cu(II)/Cu(I) with hydroxyl amine (HA). The negligible metal leaching, well-balanced thermodynamic-kinetic properties, and efficient adsorption-catalysis synergy are the main reasons for the significantly enhanced catalytic performance of CuI,II-CCCF in the removal of NPX (98.6 % at 7.0 min). The main active species in the catalytic degradation of NPX were identified (●OH > SO4●− > 1O2 > > O2●−) and consequently suggested a degradation path. It can be noted that these types of carbohydrate-based nanocomposite offer numerous advantages, encompassing simple preparation, excellent decontamination capabilities, and long-term stability.

Implementing water recirculation in a novel portable plasma-activated water reactor enhances antimicrobial effect against Escherichia coli

The need for sustainable and reliable decontamination methods is driven by concerns regarding antibiotic resistance, as well as environmental and cost-efficiency challenges associated with traditional methods. Plasma-activated water (PAW) holds significant promise as an innovative and eco-friendly decontamination method. Nevertheless, prior to industrial implementation of PAW-based decontamination devices, a deep understanding of the bacterial inactivation mechanisms and its interplay with PAW chemical composition is required. Advancing in this field requires interdisciplinary and collaborative research using standardized practices with cost-effective and shareable PAW reactors that are still missing today. Here, to this end, a portable PAW reactor, featuring a surface dielectric barrier discharge (SDBD) that operates in air, is presented. The gaseous and aqueous phases were chemically characterized by Fourier transform infrared (FTIR) absorption spectroscopy and vis-spectrophotometry, respectively. To assess PAW antimicrobial efficacy Escherichia coli was employed as a model organism on six different PAW samples for three different treatment times. The significance of water recirculation in controlling the chemical composition of PAW, altering the nitrogen species balance in favor of NO2−, is demonstrated. This chemical modification consequently enhanced the antimicrobial effectiveness of PAW, reaching a log reduction of ∼6. Exposing E. coli to equivalent concentrations of RONS to those found in PAW attained similar log-reductions, indicating that acidified nitrites are key to PAW antimicrobial activity. Through an innovative and portable design, this study illustrates the crucial role of water recirculation in tailoring PAW composition, leading to improved decontamination capabilities and establishing a key parameter for further optimization of PAW production.

Simultaneous decontamination of phosphorus and bisphenol A from livestock wastewater with boehmite-modified carbon composite

In this work, a novel boehmite-modified carbon adsorbent (BMCC) derived from moldy corn was used for simultaneous removal of P and bisphenol A (BPA) from livestock wastewater. The results showed that BMCC had a high specific surface area (308.82 m2/g) with boehmite nanoparticles anchored on its surface. BMCC showed high P and BPA decontamination capabilities (40.98 mg/g for P and 54.65 mg/g for BPA by Langmuir model). The adsorbed amount of P declined as pH increased from 4 to 10, while the adsorbed amount of BPA remained steady until pH increased to 10. After 6 cycles of BMCC use, the P and BPA adsorption efficiencies reduced by 21.75 % and 19.41 %, respectively. The adsorption of P was dominated by electrostatic attraction and complexation, while the adsorption of BPA was controlled by hydrogen bonding, electrostatic interaction, and π-π association. In conclusion, BMCC is an effective treatment for decontaminating P- and BPA-contaminated livestock wastewater.

Lysosome‐Inspired Enclosed and Deep Surface Decontamination Strategy for Management of Peri‐Implant Infections

AbstractSurface decontamination is a crucial step in the treatment of peri‐implant infections, yet deep and mild cleansing techniques are lacking. Drawing inspiration from lysosomes, which enclose hydrolytic enzymes within their membranes to safely and effectively degrade organics within cells, the use of a near‐infrared (NIR)/H2O2‐activated TiO2‐x‐Alginate system for enclosed and deep surface decontamination is proposed. It leverages synergistically generated reactive oxygen species (ROS) to eliminate bacterial contaminants, mimicking the process of lysosomal digestion. By employing Ca2+ spray‐induced surface gelation, the TiO2‐x and H2O2 around implant surface are enclosed, creating a membrane‐like isolation. This system robustly degrades extracellular polymeric substances (EPS)‐mimic biomacromolecules, removes organic residues (OR) from both mono‐species (Staphylococcus aureus and Porphyromonas gingivalis) biofilm and polymicrobial ex vivo biofilm of peri‐implantitis, while avoiding healthy tissue irritation. Encouragingly, this system has also demonstrated powerful decontamination capabilities when applied to clinic‐retrieved infected dental implants. Notably, this technique restores the pristine implant surface topography and chemical composition, which are further revealed by the minimal inflammation response observed in macrophage culture and subcutaneous implantation. Consequently, osteoblast functionalities are effectively restored, and re‐osseointegration in vivo is also greatly enhanced. Thus, this deep decontamination strategy holds great promise for clinical applications in managing peri‐implant infections.

Electronic and structural perturbations of microporous ZIF-67 nanoparticles and Cr(VI) molecule during adsorptive water decontamination unveiled by experimental and quantum computational investigations

Metal organic frameworks (MOFs) have attracted great attention due to their unique characteristics and accordingly found their way to a multitude of applications including water remediation. Co-based zeolite imidazole framework (ZIF-67) has recently shown interesting adsorptive decontamination capabilities towards metallic and organic water pollutants. Yet, ZIF-67 adsorption mechanism and stability have not been studied enough. In this study, ZIF-67 nanocrystals (∼40 nm) were synthesized and applied as an adsorbent for Cr2O72− from water. The Cr2O72−−ZIF-67 adsorption mechanism and both of Cr2O72− and ZIF-67 consequent structural changes were investigated by analyzing the elemental composition and oxidation states, the adsorption isotherms, kinetics and thermodynamics, and the optimized quantum computational models. The experimental results fitted well with pseudo-second order and Langmuir models, and gave ΔH° and ΔG° of −86.4 ± 17.6 and 12.8 ± 2.4 kJ/mol, respectively, suggesting exothermic spontaneous monolayer chemical adsorption, with maximum capacity of 370 mg/g. Kinetics also show concurrence surface adsorption with intra-particle diffusion within the micropores. XPS results reveal that both Cr6+ and the less-toxic Cr3+ co-existed in Cr2O72−−ZIF-67, whilst the Co3+/Co2+ ratio increased, referring to an oxidation–reduction reaction between Cr and Co. Computational analysis concede that the Cr2O72−−ZIF-67 high affinity is based on H-bonding between the Cr2O72− oxygens and the imidazole hydrogens, van der Waals attraction between the Cr2O72− lone pairs and the imidazole π cloud, the Cr2O72−−ZIF-67 electron transfer, and CrN coordination interaction. However, these computations show that the Cr2O72−−ZIF-67 interaction causes internal destabilization within each of Cr2O72− and ZIF-67, as Cr2O72− tends to dissociate and ZIF-67 integrity weakens.

Cold plasma as an emerging nonthermal technology for food processing: A comprehensive review

Cold plasma, a partially ionized gas maintained at low temperatures, has emerged as a promising nonthermal food processing technique with various applications, including food sterilization and improved agricultural output. By generating reactive species such as ions, radicals, and photons, cold plasma interacts with and modifies the surfaces of materials or living cells. This comprehensive review focuses on the microbial decontamination capabilities of cold plasma and its impact on a wide range of food products, including cereals, milk, fruits, vegetables, and meat. Cold plasma treatment offers distinct advantages over traditional methods such as heat treatment, chemical treatment, and irradiation. It effectively eliminates pathogenic microbes from food surfaces while preserving the quality, flavor, and nutritional content of the food. By sterilizing food surfaces and packaging materials, cold plasma significantly reduces the risk of harmful microorganism contamination. Moreover, it extends the shelf life of food products by eliminating germs, viruses, and other hazardous microbes. This review critically assesses the qualitative impact of plasma treatment, emphasizing the importance of selecting the appropriate cold plasma technology for various food products. To ensure the safety and effectiveness of cold plasma technology for commercial implementation, this review investigates the properties of cold plasma treatment for different food products. It examines the molecular connections between dietary components and cold plasma species, highlighting potential avenues for future research.

Acute care for patients exposed to a chemical attack: protocol for an international multicentric observational study

IntroductionThe use of weapons of mass destruction against civilian populations is of serious concern to public health authorities. Chemical weapons are of particular concern. A few studies have investigated medical...

P26: WashBot™ An Automatic Hand Washing Machine

Purpose: With the ongoing pandemic, the importance of handwashing has become more prevalent than ever to remove hand contaminants. The WashBot is a standalone device capable of automatically washing a user’s hands while removing the need for a user to touch anything during or after the process. A user is able to simply put their hands in the machine, allow the machine to execute various cycles, including rinsing, soaping, scrubbing, and drying cycles, and remove clean hands. Additionally, the device has built-in water tanks, eliminating the need for a water hookup and remaining water efficient. We hypothesized that the WashBot will remove macroscopic dirt, grime, oil and microbial contamination from the user’s hands, as well as demonstrate equal or superior decontamination capabilities over conventional hand washing. Methods: Tests were conducted by running a WashBot cycle. At the end of the cycle, inspection of any visible grime as well as test using a swab and petri dish growth assay were conducted to compare residual bacterial contamination of WashBot versus conventional hand washing, with an adequate subject sample size. Water and power usage are measured following each cycle and at completion of the overall process. Results: All elements of the WashBot process were successfully created and verified. The verification procedures showed the WashBot’s scrubbing process produced effective handwashing compared to conventional handwashing, with macroscopic dirt, grime, and oil being removed. In addition, petri dish test results showed the WashBot successfully removed microbial contamination and demonstrated noninferior decontamination. The overall WashBot water usage used < 2 gallons of water per run, showing an advancement compared to the conventional handwashing (4 gallons). Power results showed the WashBot able to run on standard 110V/15A wall power. Conclusion: An automated handwashing system is effective in removing visible dirt and grime as well as microbial hand contamination. Advancement of this system in an era of increased public health concern is useful in reducing inter-individual contamination.

Gaps in Prehospital Care for Patients Exposed to a Chemical Attack - A Systematic Review.

The survivability of mass casualties exposed to a chemical attack is dependent on clinical knowledge, evidence-based practice, as well as protection and decontamination capabilities. The aim of this systematic review was to identify the knowledge gaps that relate to an efficient extraction and care of mass casualties caused by exposure to chemicals. This systematic review was conducted from November 2018 through September 2020 in compliance with Cochrane guidelines. Five databases were used (MEDLINE, Web of Science Core Collection, Embase, Cochrane, and CINAHL) to retrieve studies describing interventions performed to treat victims of chemical attacks (protection, decontamination, and treatment). The outcomes were patient's health condition leading to his/her stabilization (primary) and death (secondary) due to interventions applied (medical, protection, and decontamination). Of the 2,301 papers found through the search strategy, only four publications met the eligibility criteria. According to these studies, the confirmed chemical poisoning cases in acute settings resulting from the attacks in Matsumoto (1994), Tokyo (1995), and Damascus (2014) accounted for 1,333 casualties including 11 deaths. No study reported comprehensive prehospital clinical data in acute settings. No mention was made of the integration of specialized capabilities in medical interventions such as personal protective equipment (PPE) and decontamination to prevent a secondary exposure. Unfortunately, it was not possible to perform the planned meta-analysis. This study demonstrated gaps in clinical knowledge application regarding the medical extraction of casualties exposed during a chemical attack. Further research is required to optimize clinical practice integrating mixed capabilities (protection and decontamination) for the patient and medical staff.

Surface decontamination of protective duplex oxide layers on stainless steel waste using deep eutectic solvents

The decontamination capabilities of deep eutectic solvents (DESs) formed from choline chloride (ChCl) and p-toluenesulfonic acid monohydrate (PtsA), ChCl:PtsA, under different conditions (hydrated, heated, and agitated) were tested with simulant oxidized stainless steel 304 specimens. Although the leaching rates were satisfactory under all conditions, hydrated and stirred ChCl:PtsA at 60 °C showed the fastest leaching rate of 0.1647 mg/min. Oxidized specimens with an average mass gain of 1.2 ± 1 mg were leached, and their masses were reduced by 558 ± 22 mg after 26 h. These results were understood by improved physical properties of ChCl:PtsA upon hydration. Metal oxide solubility of CoO and NiO increased with water, and those of Cr2O3 and Fe3O4 decreased with hydration. Importantly, the use of choline chloride-based DESs in decontamination applications may significantly reduce the cost of decontamination because these DESs can be mass-produced and their components are both easily obtainable and economical. Also, DESs are biodegradable and eco-friendly. The different speciation of Co and Ni, which bond with Cl-, compared with Fe and Cr, which bond with H2O, illustrated the potential for a metal recovery for secondary liquid waste reduction.

Synthesis and Decontamination Effect on Chemical and Biological Agents of Benzoxonium-Like Salts.

Benzoxonium chloride belongs to the group of quaternary ammonium salts, which have been widely used for decades as disinfectants because of their high efficacy, low toxicity, and thermal stability. In this study, we have prepared the C10-C18 set of benzoxonium-like salts to evaluate the effect of their chemical and biological decontamination capabilities. In particular, biocidal activity against a panel of bacterial strains including Staphylococcus aureus in biofilm form was screened. In addition, the most promising compounds were successfully tested against Francisella tularensis as a representative of potential biological warfare agents. From a point of view of chemical warfare protection, the efficiency of BOC-like compounds to degrade the organophosphate simulant fenitrothion was examined. Notwithstanding that no single compound with universal effectiveness was identified, a mixture of only two compounds from this group would be able to satisfactorily cover the proposed decontamination spectrum. In addition, the compounds were evaluated for their cytotoxicity as a basic safety parameter for potential use in practice. In summary, the dual effect on chemical and biological agents of benzoxonium-like salts offer attractive potential as active components of decontamination mixtures in the case of a terrorist threat or chemical or biological accidents.

Determining the Effectiveness of Decontamination with Ionized Hydrogen Peroxide.

Ionized Hydrogen Peroxide (iHP) is a new technology used for the decontamination of surfaces or laboratory areas. It utilizes a low concentration of hydrogen peroxide (H2O2) mixed with air and ionized through a cold plasma arc. This technology generates reactive oxygen species (ROS) as a means of decontamination. The purpose of this study is to evaluate the diffusion effect of iHP and its decontamination capabilities using biological and enzyme indicators. A gas-tight fumigation room with a volume of 880 ft3 was used for the decontamination trials. During the decontamination process, empty animal cages were placed inside to create fumigant distribution restrictions. Spore and enzyme indicators were placed in eleven locations throughout the decontamination room. Generation of iHP was done with the use of TOMI's SteraMist Environmental System and the SteraMist Solution, with 7.8% H2O2 at a dose of 0.5 ml per ft3. For the decontamination of 1hr, 2hrs, 6hrs, and 12hrs, the biological indicators of B. atrophaeus in Stainless Steel (SS) Disk in Tyvek envelope have an inactivation rate of 94%, 97%, 100%, and 100%, respectively. For G. stearothermophilus in SS disk and Tyvek envelope, it has 82%, 68%, 100%, and 100%, respectively and, for G. stearothermophilus in SS strips it has an effective rate of 88%, 67%, 91%, and 100%, respectively. iHP inactivates spores, and the residual tAK activity indicates a gas-like fumigant diffusion due to the uniformity of the inactivation without the use of oscillating fans as the contact time is extended.

Dual role of chemically functionalized activated carbon fibres: investigation of parameters influencing the degradation of organophosphorus compounds and antibacterial behaviour

AbstractBACKGROUNDAn efficient material possessing both photocatalytic and antimicrobial properties is necessary to remediate contaminated water resources. In the present study, zinc oxide nanorods (ZnO) have been impregnated on activated carbon fibres (ACF) to develop a heterogeneous photocatalytic system for the degradation of an organophosphorus compound, taking Malathion as a model pollutant, and to investigate the antibacterial efficiency of the former.RESULTSThe efficiency of Malathion removal varies with catalyst dosage, initial concentration of Malathion, and also depends on the interference from inorganic ions such as chloride, nitrate, sulfate, phosphate and bicarbonate in the contaminated solution. The role played by the highly active radicals in the degradation process is inevitable, confirmed by the addition of radical scavengers during the reaction. Hydroxyl radicals were found to be the most active species accountable for the degradation of Malathion. Moreover, OH trapping experiments conducted by measuring photoluminescence (PL) intensity concluded that greater amounts of OH radicals are generated with increase in time. Reusability and long‐term stability of the composite was validated for up to five degradation cycles. The developed composite also possesses microbial decontamination capabilities, verified by studying antibacterial assay against Gram positive Staphylococcus aureus and Gram negative strains of Pseudomonas aeruginosa and Klebsiella Pneumoniae.CONCLUSIONDual functional and reusable ZnO rods/ACF composites were developed using a simple, low cost hydrothermal method, and could be used as a potential candidate for water treatment applications. © 2018 Society of Chemical Industry

The health risk attenuation by simultaneous elimination of atmospheric VOCs and POPs from an e-waste dismantling workshop by an integrated de-dusting with decontamination technique

This study investigated the simultaneous abatement of atmospheric volatile organic compounds (VOCs) and persistent organic pollutants (POPs), such as polycyclic aromatic hydrocarbons (PAHs) and polybrominated diphenyl ethers (PBDEs), using an integrated technique with a bag filter (BF), photocatalysis (PC) and biotrickling filter (BTF) in an electronic waste (e-waste) dismantling workshop. Approximately 3.6×105, 1.1×103, and 2.5×103ngm−3 of VOCs, PAHs, and PBDEs, respectively, were emitted from domestic stoves during a television dismantling process. During 30-day continuous treatment period, the treatment techniques eliminated 83.7%, 87.2% and 94.1% of VOCs, PAHs and PBDEs, respectively. Among three technologies, PC was responsible for the removal of 78.0% of VOCs and 72.3% of PAHs, while the BF technology removed 85.5% of PBDEs. The success assembling of different technologies depended on different gas-particle distributions of PAHs and PBDEs. Meanwhile, the decreased risk indices of all pollutants were also observed. The PC and BF treatment technologies reduced the cancer risks associated with the most VOCs and PBDEs (57.6% and 80.5%, respectively). The BF technology reduced risks from PAHs the most (86.1%), because of much higher toxic equivalency factors associated with particle-related-PAHs. After BTF treatment, the residual organic pollutants were further biodegraded and completely detoxified. This study indicated that the integrated technique, involving both excellent de-dusting and decontamination capabilities, may provide an efficient alternative to current environment purification and human health protection practices.

Evaluation of time and temperature sufficient to inactivate porcine epidemic diarrhea virus in swine feces on metal surfaces

Objectives: To determine temperature and time applications sufficient to inactivate porcine epidemic diarrhea virus (PEDV) on a commercial livestock trailer, and practical within the constraints of current thermo-assisted drying and decontamination (TADD) capabilities in the industry. Materials and methods: Thirty-two 4-week-old barrows were inoculated via oral gastric tube with 5 mL of either PEDV-negative feces (Neg; n = 4), untreated PEDV-positive feces (Pos; n = 4), or PEDV-positive feces subjected to 71°C for 10 minutes (71C-10M; n = 4), 63°C for 10 minutes (63C-10M; n = 4), 54°C for 10 minutes (54C-10M; n = 4), 38°C for 12 hours (38C-12H; n = 4), 20°C for 24 hours (20C-24H; n = 4), or 20°C for 7 days (20C-7D; n = 4). These pigs served as a bioassay to determine the infectivity of virus following treatment. Bioassay results were determined by reverse-transcriptase polymerase chain reaction on rectal swabs collected from the inoculated pigs on days 3 and 7 post inoculation. Results: None of the pigs in the 71C-10M and 20C-7D groups became infected with PEDV. This result differed significantly from that of the Pos group (P &lt; .05). Results of the other groups did not differ significantly from that of the Pos group (P &gt; .05). Implication: Holding PEDV in the presence of feces at 71°C for 10 minutes or at 20°C (room temperature) for 7 days is sufficient to inactivate the virus, preventing transmission under the conditions of this study.

(A211) Nanosciences and CBRN Threats: Considerations about the Potential Risk of Illicit Use of Nanosystems

In the history of humankind, any new scientific discovery has shown the risk of a “dual use” for peaceful purposes or for warfare. In regard to non-conventional weapons, the recent exponential development of nanosciences and nanotechnology can provide efficient tools for counteracting these threats, by improving the detection, protection, and decontamination capabilities in the field of CBRN defence. Nevertheless, these disciplines also may offer novel, uncontrolled means of mass destruction, leading to the synthesis of new, intentionally toxic systems. Furthermore, several points of concern are linked to the new concepts of “nanotoxicology” and “nanopathology: If a multidisciplinary approach is needed to study nanosciences and nanotechnologies, a multidisciplinary approach also is needed to have a strict control on potential illegal uses of nanosystems. Experts active in various fields, such as academic, industrial, military, and health protection institutions, must work cooperatively to constantly follow the state of the art, note which kind of critical emerging technologies may lead to illicit uses, and control the diffusion of hazardous nanosystems that may be potential precursors of weapons of mass destruction, and cooperate with CBRN emergency prevention organizations in order to plan suitable countermeasures. This presentation will cover some examples of nanosystems applied to defense from non-conventional warfare agents and answer questions regarding potential misuses of basic nanoscience and nanotechnology findings.

HDT Mixtures Treatment Strategies by Gas Chromatography

Gas phase chromatographic processes are of interest for the separation of hydrogen isotopes from an HDT mixture. For a certain quantity, they are very competitive and present several benefits. Nevertheless no active packing material allows to have simultaneously good enrichment performances for tritium production and high decontamination capabilities for HD gases. The influence of the packing material is first described in this article. Then two specific processes (TCAP and Reverse Chromatography), each well adapted to perform one target, are presented. Finally, the problematic to propose an optimized treatment scheme associating these two processes is formulated.