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Purpose: To achieve high plaque removal around peri-implant tissues, noninvasive cleaning methods that guarantee the long-term success and survival of titanium implants should be established. This systematic review aimed to systematically evaluate in vitro investigations assessing different treatment modalities to decontaminate titanium surfaces, with special focus on the most effective cleaning procedures. Materials and Methods: PRISMA guidelines were adopted in an electronic search conducted through MEDLINE, Scopus, and Google Scholar databases to identify studies on mechanical, chemical, or laser decontamination modalities up to November 2019. Results: The search resulted in 326 articles; after removing duplicates and reading titles, abstracts, and full texts, 38 articles were ultimately processed for data extraction. Mechanical decontamination provided better results in comparison to laser and chemical procedures. Among mechanical modalities, air abrasion showed the best cleaning effectiveness. Conversely, upon comparison of the chemical methods, chlorhexidine demonstrated comparable results with all tested substances and even with photodynamic therapy. Among different lasers, the results showed that the diode was more promising compared with the other tested lasers. Conclusion: This review demonstrated that there is still no consensus on which technique performs better. However, mechanical decontamination yielded more favorable results than laser and chemical methods. This aspect would support the hypothesis that decontamination procedures adopted in a combination fashion, which includes mechanical procedures, may provide better clinical results than when used alone. [ABSTRACT FROM AUTHOR]

Eradicating biofouling from implant surfaces is essential in treating peri-implant infections, as it directly addresses the microbial source for infection and inflammation around dental implants. This controlled laboratory study examines the effectiveness of the four commercially available debridement solutions '(EDTA (Prefgel®), NaOCl (Perisolv®), H2O2 (Sigma-Aldrich) and Chlorhexidine (GUM® Paroex®))' in removing the acquired pellicle, preventing pellicle re-formation and removing of a multi-species oral biofilm growing on a titanium implant surface, and compare the results with the effect of a novel formulation of a peroxide-activated 'Poloxamer gel (Nubone® Clean)'. Evaluation of pellicle removal and re-formation was conducted using scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy to assess the surface morphology, elemental composition and chemical surface composition. Hydrophilicity was assessed through contact angle measurements. The multi-species biofilm model included Streptococcus oralis , Fusobacterium nucleatum and Aggregatibacter actinomycetemcomitans , reflecting the natural oral microbiome's complexity. Biofilm biomass was quantified using safranin staining, biofilm viability was evaluated using confocal laser scanning microscopy, and SEM was used for morphological analyses of the biofilm. Results indicated that while no single agent completely eradicated the biofilm, the 'Poloxamer gel' activated with 'H2O2' exhibited promising results. It minimized re-contamination of the pellicle by significantly lowering the contact angle, indicating enhanced hydrophilicity. This combination also showed a notable reduction in carbon contaminants, suggesting the effective removal of organic residues from the titanium surface, in addition to effectively reducing viable bacterial counts. In conclusion, the 'Poloxamer gel + H2O2' combination emerged as a promising chemical decontamination strategy for peri-implant diseases. It underlines the importance of tailoring treatment methods to the unique microbial challenges in peri-implant diseases and the necessity of combining chemical decontaminating strategies with established mechanical cleaning procedures for optimal management of peri-implant diseases. [ABSTRACT FROM AUTHOR]

Surface chemistry evaluation is crucial in assessing the efficacy of chemical decontamination products for titanium implants. This study aimed to investigate the effectiveness of chemical decontamination solutions in cleaning a contaminated dental implant surface and to evaluate the potential of combining Pluronic gel with hydrogen peroxide (NuBone®Clean) by evaluating pellicle disruption and re-formation on implant surfaces. In addition, ensuring safety with in vitro and human testing protocols. X-ray Photoelectron Spectroscopy (XPS) was utilised for surface analysis. All the tested gels had some effect on the surface cleanness except for PrefGel®. Among the tested chemical decontamination candidates, NuBone®Clean demonstrated effectiveness in providing a cleaner titanium surface. Furthermore, none of the tested chemical agents exhibited cytotoxic effects, and the safety assessment showed no adverse events. The results of this study highlight the significance of conducting comprehensive evaluations, encompassing safety and efficacy, before introducing new chemical agents for dental treatments. The findings suggest that NuBone®Clean shows potential as a chemical decontamination solution for implant surfaces. However, further investigation through randomised clinical trials is necessary. By adhering to rigorous testing protocols, the development of safe and efficient chemical decontamination strategies can be advanced, benefiting patients and promoting progress in implant dentistry. [ABSTRACT FROM AUTHOR]

Occupational radiation exposure has been one of the most important issues in light water reactors. The radiation source is dominantly radioactive cobalt incorporated in oxide film on structural materials. To lower radiation intensity, zinc injection has been implemented widely in light water reactors. Application of the zinc injection leads to incorporation of zinc in the oxide film and changes in the oxide film. Chemical decontamination is applied after shutdown and removes the radioactive cobalt. When the chemical decontamination was applied to plants which experienced the zinc injection, decontamination factor was sometimes lower than before the zinc injection. Then, in the present work thermodynamic solubility of divalent cobalt and divalent zinc was calculated with a thermodynamic code, assuming typical conditions of oxidizing steps of the chemical decontamination. It has been concluded that the solubility limit of divalent cobalt is 22 to 26 times higher than that of divalent zinc under any oxidizing condition. These figures are consistent with the plant data observed during the application of the chemical decontamination. It has been concluded that the oxidizing step of the typical chemical decontamination methods are suitable condition for effective dissolution of cobalt and less effective dissolution of zinc.

Base metal corrosion forms a significant issue during the chemical decontamination of the primary coolant loop in nuclear power plants as it is directly related to the economic and safety viability of decommissioning. In this technical note, potentiodynamic evaluations of several base metals (304 stainless steel, SA106 Grade B carbon steel, and alloy 600) were performed to determine their corrosion behavior during the hydrazine (N2H4)-based reductive ion decontamination (HyBRID) process. The results suggested that N2H4 protected the surface of the base metals in the HyBRID solution, which is primarily composed of H2SO4. The corrosion resistance of the carbon steel was further improved through the addition of CuSO4 to the solution. The corrosion rate of carbon steel in the H2SO4-N2H4-CuSO4 solution was lower than that exhibited in an oxalic acid solution, a commonly used reaction medium during commercial decontamination processes. These results indicate the superiority of the HyBRID process with respect to the base metal stability.

Objectives: To evaluate ex vivo the efficacy of an amino acid buffered hypochlorite solution supplemented to surface debridement with air-powder abrasion in removing bacterial biofilm following open-flap decontamination of implants failed due to peri-implantitis. Materials and methods: This study was an ex vivo, single-blind, randomized, intra-subject investigation. Study population consisted of 20 subjects with at least three implants failed for peri-implantitis (in function for > 12 months and progressive bone loss exceeding 50%) to be explanted. For each patient, implants were randomly assigned to surface decontamination with sodium bicarbonate air-powder abrasion (test-group 1) or sodium bicarbonate air-powder abrasion supplemented by amino acid buffered hypochlorite solution (test-group 2) or untreated control group. Following open-flap surgery, untreated implants (control group) were explanted. Afterwards, test implants were decontaminated according to allocation and explanted. Microbiological analysis was expressed in colony-forming units (CFU/ml). Results: A statistically significant difference in the concentrations of CFU/ml was found between implants of test-group 1 (63,018.18 ± 228,599.36) (p = 0.007) and implants of test-group 2 (260.00 ± 375.80) (p < 0.001) compared to untreated implants (control group) (86,846.15 ± 266,689.44). The concentration of CFU/ml on implant surfaces was lower in test-group 2 than in test-group 1, with a statistically significant difference (p < 0.001). Conclusion: The additional application of amino acid buffered hypochlorite solution seemed to improve the effectiveness of implant surface decontamination with air-powder abrasion following open-flap surgery. Clinical relevance. Lacking evidence on the most effective method for biofilm removal from contaminated implant surfaces, the present experimental study provides further information for clinicians and researchers. [ABSTRACT FROM AUTHOR]

The chemical stability of base metals in a nuclear facility is critical for chemical decontamination because the process typically utilizes a corrosive solution as a reaction medium. An electrochemical corrosion study on SA106 Grade B (SA106B) carbon steel, a feeder pipe material in a Canadian Deuterium Uranium (CANDU) pressurized heavy water reactor, was performed to examine its stability in a hydrazine (N2H4)-based reductive metal ion decontamination (HyBRID) process. The corrosion rate of SA106B in the HyBRID process was reduced by introducing corrosion inhibitors, such as chrysoidine G (CG) and CI#30. The corrosion current (Icorr) of SA106B in the H2SO4-N2H4 solution, a reaction medium of the HyBRID process, was reduced to approximately 30% and 20% in the presence of CG and CI#30, respectively. The Icorr obtained in the HyBRID solution containing the corrosion inhibitor was comparable to that obtained in the organic acid solution used for the commercial process, Canadian decontamination and remediation (CAN-DEREM). Our results indicate that sufficient material stability of SA106B against corrosion during the HyBRID process can be realized by adding a corrosion inhibitor for the chemical decontamination of the CANDU reactor. [ABSTRACT FROM AUTHOR]

Surface chemistry evaluation is crucial in assessing the efficacy of chemical decontamination products for titanium implants. This study aimed to investigate the effectiveness of chemical decontamination solutions in cleaning a contaminated dental implant surface and to evaluate the potential of combining Pluronic gel with hydrogen peroxide (NuBone®Clean) by evaluating pellicle disruption and re-formation on implant surfaces. In addition, ensuring safety with in vitro and human testing protocols. X-ray Photoelectron Spectroscopy (XPS) was utilised for surface analysis. All the tested gels had some effect on the surface cleanness except for PrefGel®. Among the tested chemical decontamination candidates, NuBone®Clean demonstrated effectiveness in providing a cleaner titanium surface. Furthermore, none of the tested chemical agents exhibited cytotoxic effects, and the safety assessment showed no adverse events. The results of this study highlight the significance of conducting comprehensive evaluations, encompassing safety and efficacy, before introducing new chemical agents for dental treatments. The findings suggest that NuBone®Clean shows potential as a chemical decontamination solution for implant surfaces. However, further investigation through randomised clinical trials is necessary. By adhering to rigorous testing protocols, the development of safe and efficient chemical decontamination strategies can be advanced, benefiting patients and promoting progress in implant dentistry.

Soap and water are often considered the gold standard for dermal decontamination. However, recent systematic reviews have shown that these methods often result in incomplete decontamination and may even induce contaminant absorption due to the "wash‐in" effect. Therefore, it is important to gain insight on other decontamination methods. A literature search was done using PubMed to find experimental studies relating to dry decontamination performed with readily available items. Seven studies met eligibility criteria, and the study model, dry decontaminant, method of dry decontamination, method of analyzing decontamination, and main conclusions from each study were extracted, summarized, and compared. Important conclusions include that all studies investigated found that dry decontamination yielded decreases in contamination. In addition, it was shown by multiple studies that not only the decontaminant, but the manner in which it is used (method used [blotting, rubbing, etc.], amount used, and whether decontamination instructions are provided to exposed individuals) is vital to success. Finally, in all four studies that investigated wet and dry decontamination combination protocols, combinations were more efficacious than dry decontamination alone. However, this means that dry improvised decontamination can be performed while waiting for the deployment and arrival of further formal decontaminants. These conclusions deserve consideration in the event that universal decontamination guidelines are designed. However, more studies are required in order to draw definitive conclusions regarding the important topic of dermal decontamination. This review explores the efficacy of readily available dry decontaminants. Seven studies met inclusion criteria, and all found that dry decontamination yielded decreases in contamination. Multiple found that not only the decontaminant, but the way it is used is vital to success. All studies investigating combination (wet and dry) protocols found they were more efficacious than dry decontamination alone. Thus, dry decontamination should be performed while awaiting deployment/arrival of additional formal decontaminants. More studies are required to optimize decontamination guidelines. [ABSTRACT FROM AUTHOR]

Water and/or soap and water solutions have historically been used as first‐line decontamination strategies for a wide variety of dermal contaminants from workplace exposure, environmental pesticides, and civilian chemical warfare. Although water and/or soap and water solutions are often considered a gold standard of decontamination, many studies have found other decontamination methods to be superior. This systematic review summarizes the available data on in vitro animal models contaminated with a various chemicals and their decontamination with water and/or soap and water solutions using in vitro animal models. A comprehensive literature search was performed using Concordance, Embase, PubMed, Medline, Web of Science, and Google Scholar to find in vitro animal studies that provided data on dermal decontamination using water and/or soap and water solutions. Five studies were included that analyzed 11 contaminants across two in vitro animal models (rats and pigs). Water alone was used as a decontamination method for 63.6% of the contaminants (n = 7/11) and water and soap solutions for decontamination in 54.6% of contaminants (n = 6/11). Water alone provided incomplete contaminant removal of five of seven contaminants studied; soap and water did not show significant difference in decontamination when compared with other solutions for all four contaminants and was superior to water for both contaminants studied. Water and/or soap and water are used as decontamination strategies for a variety of dermal contamination events, but for many contaminants, they do not provide complete contamination when compared with newer decontamination solutions studied with in vitro animal models. This systematic review compares water and/or soap and water dermal decontamination to other decontamination solutions using in vitro animal models. Five studies met inclusion criteria that analyzed 11 contaminants across two animal models. Water provided incomplete decontamination for 5/7 contaminants studied. Soap and water was superior to water alone for both contaminants studied and did not show significantly different decontamination efficacy compared with other solutions in 4/4 contaminants. Additional research is needed to continue improving efficacy of dermal decontamination solutions. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the most effective chemotherapeutic agent for decontamination of infected dental implants. Material and methods: A systematic electronic literature search in MEDLINE (PubMed) and Google scholar between January 2010 to December 2021 was carried out by using the PRISMA guidelines. A total of five studies related to chemical decontamination of the dental implant were evaluated. The search strategy was based on the PICOS framework. Randomized controlled trials (RCT's) and cohort studies evaluating the effectiveness of different chemotherapeutic agents for the decontamination of dental implants were included in the study. The outcome variable examined was the most effective chemotherapeutic agent(s) for dental implant surface decontamination after comparing the chemotherapeutic agents used in the qualifying studies. Result: Out of the basic database of 1564 records, 1380 articles were excluded due to irrelevance, unavailability, and repetition. Furthermore, 134 articles were excluded from 184 studies for various reasons. After further filtration, 13 studies were shortlisted. Two investigators (SSA and SA) appraised the quality of the selected studies using the risk of bias assessment tool. After excluding eight studies, five articles were finally included in the present systematic review. Conclusion: The data reported for the efficacy of chemotherapeutic agents in cleaning contaminated titanium surfaces are scarce, thus it is not possible to draw a definite conclusion. However, chlorhexidine (CHX) (0.2%, 0.12%), citric acid (40%) and sodium hypochlorite (1%) are the most commonly used chemotherapeutic agents; amongst them, citric acid showed the highest potential for biofilm removal from the contaminated implant surface. All three agents [CHX (0.2%, 0.12%), citric acid (40%), and sodium hypochlorite (1%)] can be recommended as therapeutic agents along with their curbs. [ABSTRACT FROM AUTHOR]

The removal of radionuclides from the primary coolant system of nuclear power plants occurs with the dissolution of corrosion metal oxide layers deposited with the radionuclides. Kinetic dissolution experiments were conducted with a synthetic magnetite specimen in the form of a thin plate using an aqueous solution of oxalic acid as a reducing agent. The effects of acid concentration and temperature were investigated on the kinetics of the reductive dissolution of a magnetite specimen. In particular, the kinetic experiments were performed in a wide temperature range from low (57 °C) to high (120 °C), above the normal boiling point of water. The dissolution of magnetite increased with increasing acid concentration and temperature. The acid concentration dependence of the dissolution reaction rate of Fe at a given temperature was correlated with the nth power of the oxalic acid concentration. Additionally, the temperature dependence of the dissolution reaction rate of Fe at a fixed oxalic acid concentration was studied with an Arrhenius-type equation. [ABSTRACT FROM AUTHOR]

With the constant possibility of occupational exposures, chemical warfare, and targeted attacks, increased attention has been given to determining effective and timely dermal decontamination strategies. This systematic review summarises experimental studies reporting decontamination with water-based solutions of dermal chemical contaminants with in vivo human data. Embase, MEDLINE, PubMed, Web of Science, and Google Scholar databases were comprehensively searched using search terms ("cutaneous" or "skin" or "dermal" or "percutaneous") and ("decontamination" or "decontaminant" or "skin decontamination") to include 10 studies, representing 18 chemical contaminants, 199 participants, and 351 decontamination outcomes. Three studies included data from decontamination with water (10.8%, n = 38/351 decontamination outcomes), seven with soap and water (68.4%, n = 240/351 decontamination outcomes), and two with 10% isopropanol distilled water (20.8%, n = 73/351 decontamination outcomes). Results of dermal decontamination using water showed complete decontamination (CD) outcomes in 52.6% (n = 20/38) and partial decontamination (PD) in 47.4% (n = 18/38); using soap and water showed PD outcomes in 92.9% (n = 223/240) and minimal to no effect in 7.1% (n = 17/240); and using 10% isopropanol distilled water achieved PD outcomes in 100.0% (n = 73/73). Available data show that decontamination with water, soap and water, and 10% isopropanol distilled water is incomplete. Much remains to be learned about decontamination of the large variety of chemical contaminants including a range of molecular weights, lipid and water solubilities, melting points, volatility, and hydrogen bonds, as well as clinically relevant anatomic sites. A major void exists in data confirming or denying the completeness of decontamination by measuring absorption and excretion. The development of effective decontamination solutions is of high priority. [ABSTRACT FROM AUTHOR]

Systematic review and meta‐analysis were conducted to quantify the effects of processing stages and interventions on the prevalence and concentration of Campylobacter on broiler carcasses. To comprehensively capture relevant evidence, six databases were searched using the keywords "Campylobacter" and "broiler chicken." The literature search yielded 10,450 unique citations, and after applying predetermined inclusion and exclusion criteria, 72 and 53 relevant citations were included in meta‐analyses for processing stages and interventions, respectively. As the two primary outcomes, log reduction and prevalence changes were estimated for each stage or intervention using a random‐effects meta‐analysis approach whenever possible. The outcome‐level quality assessment was conducted following the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. The analysis revealed that scalding and chilling majorly reduces the prevalence and concentration of Campylobacter. Immersion chilling reduces the concentration regardless of chemical additives, but its effect on prevalence is not conclusive. The effects of carcass washing applications remain uncertain due to the inconsistency and imprecision of both outcomes. Defeathering and evisceration were identified as stages that can increase both prevalence and concentration. Both chemical and physical processing interventions provide limited efficacy in concentration and prevalence reduction. Major limitations of the review were inconsistency and imprecision at the outcome level and reporting issues and data gaps at the study level. The results are expected to inform quantitative microbial risk assessment model development and support evidence‐based decision‐making. [ABSTRACT FROM AUTHOR]

Water-only or soap and water solutions are considered a gold standard for skin decontamination. However, there is lack of conclusive data regarding their efficacy. The aim of this study was to summarize in vivo animal model data on skin decontamination using water-only, and/or soap and water. Covidence, Embase, MEDLINE, PubMed, Web of Science, and Google Scholar were searched to identify relevant articles using water-only or soap and water decontamination methods in in vivo animals. Data extraction was completed from studies, representing three animal models, and 11 contaminants. Results demonstrated water-only decontamination solutions led to complete decontamination in 3.1% (n = 16/524) protocols, incomplete decontamination in 90.6% (n = 475/524) of protocols, and mortality in 6.3% (n = 33/524) of protocols. Soap and water decontamination solutions resulted in complete decontamination in 6.9% (n = 8/116) protocols, incomplete decontamination in 92.2% (n = 107/116) of protocols, and mortality in 6.9% (n = 8/116) of protocols. Although water only, or soap and water is considered a gold standard for skin decontamination, most papers investigated found that water only, and soap and water provided incomplete decontamination. Due to the insufficient data, and limitations that hinder the applicability of available data, evidence indicates that more contemporary studies investigating skin decontamination are needed, and compared to other model species, including humans, when practical. [ABSTRACT FROM AUTHOR]

Here we present a newly developed two-step oxidative-reductive in-service chemical decontamination process suitable for high temperature and high pressure circuit (HTHPC) decontamination in a pressurized water reactor (PWR). Various process parameters on the corrosion depth and decontamination factor were investigated by employing different kinds of detergents. Under optimal conditions, the average decontamination factor is about 60.0 and the maximum corrosion depth is 0.20 um. Actual decontamination by applying this process to HTHPC, the dose field in most locations decreased by more than 89% and it's proved that the decontamination process is completely suitable for the decontamination of PWRs in service. [ABSTRACT FROM AUTHOR]

Objectives: To compare, using an ex vivo model, the biofilm removal of three surface decontamination methods following surgical exposure of implants failed for severe peri-implantitis. Materials and methods: The study design was a single-blind, randomized, controlled, ex vivo investigation with intra-subject control. Study participants were 20 consecutive patients with at least 4 hopeless implants, in function for >12 months and with progressive bone loss exceeding 50%, which had to be explanted. Implants of each patient were randomly assigned to the untreated control group or one of the three decontamination procedures: mechanical debridement with air-powder abrasion, chemical decontamination with hydrogen peroxide and chlorhexidine gluconate, or combined mechanical-chemical decontamination. Following surgical exposure, implants selected as control were retrieved, and afterwards, test implants were decontaminated according to allocation and carefully explanted with a removal kit. Microbiological analysis was expressed in colony-forming-units (CFU/ml). Results: A statistically significant difference (p < 0.001) in the concentrations of CFU/ml was found between implants treated with mechanical debridement (531.58 ± 372.07) or combined mechanical-chemical decontamination (954.05 ± 2219.31) and implants untreated (37,800.00 ± 46,837.05) or treated with chemical decontamination alone (29,650.00 ± 42,596.20). No statistically significant difference (p = 1.000) was found between mechanical debridement used alone or supplemented with chemical decontamination. Microbiological analyses identified 21 microbial species, without significant differences between control and treatment groups. Conclusions: Bacterial biofilm removal from infected implant surfaces was significantly superior for mechanical debridement than chemical decontamination. Clinical relevance: The present is the only ex vivo study based on decontamination methods for removing actual and mature biofilm from infected implant surfaces in patients with peri-implantitis. [ABSTRACT FROM AUTHOR]

Fission isotopes contribute approximately 10% of the total radioactivity removed from the heat transport circuit of reactor systems during the chemical decontamination process. Simulated corrosion products (SCP) (CrFeO3 and MxCrFe1−xO3) and with fission isotope substituted in SCP [MxNiCrFe1−xO4 (M = La, Ce and Zr; x ≤ 0.05)] were synthesised and its dissolution behavior were studied in permanganate medium. Fission isotope metal ion substitution in SCP showed enhanced 'Cr' dissolution rates during the permanganate treatment. Among the fission isotope (La, Ce and Zr) substituted oxide dissolution studies, 'La' release was more compare to 'Ce' and 'Zr'. The release behavior of fission products studies showed that dissolved lanthanum is getting sorbed onto the insitu formed MnO2. [ABSTRACT FROM AUTHOR]

Objectives Over the past 40 years, numerous actions have been undertaken to decrease the contamination of hospital facilities by intravenous conventional antineoplastic drugs (ICADs) such as centralizing compounding in pharmacies, using personal protective equipment, specific compounding, or infusion devices. As recently proposed in the monograph, an additional specific decontamination step must be envisaged. A recent literature review analysed and discussed the different solutions tested in terms of decontamination efficacy. This article aims to discuss the performance of these solutions in the framework of aseptic compounding. Methods The same dataset used in the previous literature review was reanalysed according to other parameters so as to select decontamination solutions: overall decontamination efficiency (EffQ), tested contaminants, and the risks of use in daily practice. Results Using an EffQ threshold of 90% resulted in discarding 26 out of the 59 solutions. Solutions were tested differently: 8 on 1 contaminant, 11 on 2 contaminants, and 14 solutions on between 3 and 11 contaminants. Three risks were identified to help make choices in routine practice: the mutagenicity of degradation products, the safety of operators and facilities, and respect for the aseptic environment. Conclusions From the results, performance is discussed according to specific situations: a one-time incident or the basic chemical contamination due to daily practice. Accordingly, the decontamination solution selected then required a risk analysis and an evaluation before implementing it in the daily practice of a compounding unit. [ABSTRACT FROM AUTHOR]

The study presents the results of deep decontamination of the spent ion-exchange resin from the Kursk NPP, where the task of processing and conditioning of the resin is still not solved. The article shows that decontamination of the resin under dynamic conditions with a solution of the composition NaOH – 0.75 mol L−1, NaNO3 – 2.25 mol L−1 reduces its activity by 1 order of magnitude due to removal of Cs-137 (by washing). The subsequent washing of the resin with a solution of H 2 SO 4 – 1.0 mol L−1, FeSO 4 – 0.5 mol L−1 results in a decrease of its activity by another 1 order of magnitude due to removal of Eu-152-154 (100%) and partial removal of Co-60 (90%) and Am-241 (92%). It was found that further attempts to reduce the activity of the resin were ineffective due to the presence of insoluble precipitates, whose activity was mainly (more than 98%) accounted for by Co-60 (30.2%) and Nb-94 (68.1%) radionuclides. To remove these poorly soluble precipitates, we suggested decontamination by direct current through placing the resin between an anode and a cathode. A solution of H 2 SO 4 of a concentration of 0.1 mol L−1 was used as an electrolyte. It has been found that an addition of FeSO 4 (0.009 mol L−1) increases the rate of precipitate removal more than 1.5-fold. During the treatment by electric current, particles are mechanically removed, whereas insignificant amounts of Cs-137 and Co-60 (no more than 2.6%) enter the electrolyte. After the treatment and washing the resin with a NaNO 3 solution, its activity decreases by another three orders of magnitude. The resulting activity of the resin was 350 Bq kg−1, which made it possible to classify it as industrial waste. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to compare different surgical therapies to treat peri-implantitis.Methods: Twenty-three patients presenting one implant affected by peri-implantitis were divided into three groups: (i) open flap debridement (OFD) and citric acid decontamination (CAD); (ii) OFD, CAD and subepithelial connective tissue graft (SCTG); (iii) OFD, CAD and implantoplasty. Modified plaque index (MPI), gingival bleeding index (GBI), keratinized mucosa (KM) width, probing depth (PD), bleeding or suppuration on probing (B/SOP), and radiographic crestal bone level were registered 1(T1), 2(T2) and 3(T3) years after treatment.Results: In Group 1 there was a significant improvement in MPI from baseline to T1, and a significant reduction in PD over time. In Group 2, none of the assessed clinical parameters showed any statistically significant variation over time. In Group 3, there was a significant decrease in PD and B/SOP over time. When comparing the 3 Groups, KM was significanlty greater in Group 2 vs. Group 1 and Group 3 at T1 and T2, and in Group 2 vs. Group 3 at T3.Conclusion: All therapies were successful in the management of peri-implantitis; however, SCTG maintained the greatest KM width. Surgical therapies combined with mechanical and chemical decontamination contributed to peri-implant tissue health. [ABSTRACT FROM AUTHOR]

In order to understand the electrochemical behavior of ascorbic acid organic acid detergent for chemical decontamination of nuclear power plant and improve its decontamination effect？ the main corrosion product (Fe3O4) in the pipelines of nuclear power plant was made into a chemically modified electrode by the fixing action of Nafion solution in this paper. The electrochemical behavior of Fe3O4i in ascorbic acid was studied by three-electrode system. The effects of scanning speed ？ solution concentration and reaction type were also investigated. At the same time, tests such as cyclic voltammetry, polarization curves and AC impedance were also performed. The electrochemical behavior of Fe3O4i in ascorbic acid was analyzed and a series of electrochemical data were obtained. [ABSTRACT FROM AUTHOR]

Cost-effective approaches for microbial decontamination of cereals are of great industrial interest to reduce post-harvest crop losses and consumer health hazards. The objective of this study was to screen a range of 13 treatments, including physical (high hydrostatic pressure, ultrasound, vacuum packaging and microwaves with and without sodium hypochlorite), chemical (hydrogen peroxide, sodium hypochlorite, acetic acid, sorbate, propionate, quaternary ammonium compounds, and cold plasma), and microbiological (lactic acid bacteria) decontamination, on artificially infected wheat prior to storage in a model system for 6 weeks. Each treatment success, compared to positive and negative controls, was evaluated based on fungal bio-mass and accumulation of 13 mycotoxins during storage. To estimate the treatments impact on grain quality and technological performance, a comprehensive flour analysis was carried out, including activities of important wheat enzymes, soluble protein distribution, and gluten characterisation. The treated grains were also used to bake whole grain breads. The breads were analysed for quality parameters such as specific loaf volume, crumb structure, and physical crumb texture. Best decontamination procedures were found to be vacuum packaging, high hydrostatic pressure, microwave, sorbate, and propionate treatments, which fully inhibited fungal development and mycotoxin production. Deterioration in grain quality for the use in baking was found due to the microwave treatment as a result of the internal heating. The comparison of traditional methods with the novel approaches revealed that the conventional methods remain superior to the novel approaches due to their simplicity and efficiency without negative impact on the grains. [ABSTRACT FROM AUTHOR]

Abstract Strawberries are one of the most important fruits in the Mediterranean diet and have been widely investigated for their nutritional and nutraceutical properties. Concern about the safety of fresh and processed strawberries has increased in recent years due to the emergence of several outbreaks of foodborne pathogens linked to their consumption. The use of chlorine as a disinfectant has been identified as a concern due to public health issues and limited efficacy at removing contamination, and preventing cross-contamination. This has led to the development of novel alternatives to chlorine disinfection and thermal treatments, which include, among others, the use of organic acids, high pressure processing, intense pulsed light, or pulsed electric fields. These technologies do not generally affect the nutritional and organoleptic properties of the product and some of these have been reported to stimulate the production of valuable compounds in strawberries and to improve their overall quality. Highlights • The use of chlorine has been identified as a concern. • Viruses (NoV and HAV) are the most relevant pathogens associated with strawberries. • Alternative chemical strategies proved to be excellent alternatives. • Novel non-thermal technologies generally result in better quality retention. • Microwave and ohmic heating show potential as substituents of conventional thermal treatments. [ABSTRACT FROM AUTHOR]

The spontaneous reductive decomposition behavior of HMnO4 in water as a function of the initial HMnO4 concentration and reaction temperature was investigated. The decomposition of HMnO4 was fast in the early stage of the reaction and thereafter slowed down significantly, regardless of the initial HMnO4 concentration. The loss of HMnO4 by spontaneous reductive decomposition increased with increasing reaction temperature. Based on the experimental results and the classical nucleation theory, a mathematical model was developed using a combination of two first-order reactions representing the nucleation and crystal growth of MnO2 to predict the spontaneous reductive decomposition behavior of HMnO4. [ABSTRACT FROM AUTHOR]

Ultrasonic electrochemical decontamination technology is a decontamination method coupled with electrochemical decontamination and ultrasonic decontamination. This article reports the study of ultrasonic electrochemical decontamination on the surface of stainless steel. The decontamination effect of ultrasonic electrochemical decontamination compared with electrochemical decontamination in the study. The results show that the ultrasonic assisted electrochemical decontamination has the advantages such as good decontamination efficiency, simple equipment, less chemical reagents, single species and less waste of two times, etc. [ABSTRACT FROM AUTHOR]

Ni-Cr-Fe mixed oxides (NiCr x Fe 2-x O 4 ) are formed as a corrosion oxide films on structural material surface of coolant or heat transport circuit in water-cooled nuclear reactors. Study on the dissolution behavior of these oxides forms a critical part in development of an efficient chemical decontamination process for the nuclear industry. The present study describes release of Ni and Cr in permanganate medium from the chromium substituted nickel ferrite and also on the mechanistic aspects of oxide dissolution. These oxides were synthesized by combustion method and characterized by the XRD, XPS and Raman spectroscopy. The dissolution kinetics of oxide in permanganate medium was modeled by Shrinking Sphere Model and General Kinetic law Equation. The rate constant for oxide dissolution increased with the Cr substitution in nickel ferrite. Presence of chromium in the oxide lattice affect the release of nickel and also a minimum chromium concentration in the lattice is required for the release of nickel from the oxide lattice during the permanganate treatment. However, when the chromium substitution ( x ) is increased to 0.6 and above, the nickel release was lowered. [ABSTRACT FROM AUTHOR]

Manufacture and recreational use of methamphetamine can result in widespread chemical contamination throughout a property. Hydrogen peroxide (H 2 O 2)-based cleaning products have shown success against a number of chemical contaminants including agents of chemical warfare, and biological contaminants such as anthrax. They are considered to be environmentally friendly and economically viable and, as such, are used by many companies within the methamphetamine decontamination industry. The oxidative decontamination of methamphetamine and ephedrine hydrochloride was investigated in this current study, employing a commercially available H 2 O 2 -based decontamination product, Bio-Oxygen® Chem Decon. Methamphetamine and ephedrine were observed to degrade following pseudo-first order kinetics of (1.9 ± 0.4) × 10−2 min−1 and (2.2 ± 0.3) × 10−2 min−1, respectively. Major oxidation products identified through GC-MS analyses were phenylacetone oxime (from methamphetamine) and benzaldehyde (from ephedrine). LC-MS analysis revealed the presence of a number of N -oxygenated intermediates which allowed for the elucidation of an N -oxidation decomposition pathway reminiscent of flavin-containing monooxygenase enzymes. Using this information, further targeted research can be performed to understand the behaviour and persistence of these reaction products and accurate assessments can be achieved to estimate their impact on the exposure risks associated with chemical decontamination of amphetamine-type stimulants (ATS). [Display omitted] • Distinctive product (phenyl acetone oxime) produced when methamphetamine reacts with activated hydrogen peroxide. • Reaction of ephedrine with activated hydrogen peroxide mainly gives benzaldehyde. • N-oxidised compounds form as initial degradation products from methamphetamine. [ABSTRACT FROM AUTHOR]

The Kori Unit 1, a first nuclear power plant (NPP) in South Korea stopped operation permanently on June 18, 2017 after 40 years of operation. Before the main decommissioning activities begin, full-system chemical decontamination operation (FSCDO) of the primary systems is planned to secure the safety of workers and minimize the quantity of radioactive waste. In this study, the radioactive inventory at the time of decommissioning of Kori Unit 1 was investigated. The CRUDTRAN code was used to make predictions by using the actual operation and maintenance history and design data of Kori Unit 1. Regarding the steam generator (SG), the prediction results obtained using the CRUDTRAN code were 17–30% higher or more conservative than the direct measurement results obtained using survey meters. By applying the oxide layer removal ratio (OLRR; obtained through a chemical decontamination field test using the contaminated specimen) to the oxidation/deoxidation process during FSCDO, the removal rate of radioactive inventory could be predicted. As an actual decommissioning work proceeds, the detailed data of radioactive elements in RCS systems can be obtained through sampling and chemical analysis. Those data will be much valuable for both the operation and future decommissioning of current NPPs. [ABSTRACT FROM AUTHOR]

Decontamination for military purposes represents the process of removing/neutralizing of [...]

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Mycotoxins are secondary metabolites produced by several filamentous fungi, which frequently contaminate our food, and can result in human diseases affecting vital systems such as the nervous and immune systems. They can also trigger various forms of cancer. Intensive food production is contributing to incorrect handling, transport and storage of the food, resulting in increased levels of mycotoxin contamination. Mycotoxins are structurally very diverse molecules necessitating versatile food decontamination approaches, which are grouped into physical, chemical and biological techniques. In this review, a new and promising approach involving the use of cold atmospheric pressure plasma is considered, which may overcome multiple weaknesses associated with the classical methods. In addition to its mycotoxin destruction efficiency, cold atmospheric pressure plasma is cost effective, ecologically neutral and has a negligible effect on the quality of food products following treatment in comparison to classical methods. [ABSTRACT FROM AUTHOR]

Chemical, biological, radiological, and nuclear (CBRN) decontamination is the removal of CBRN material from equipment or humans. The objective of the decontamination is to reduce radiation burden, salvage equipment, and materials, remove loose CBRN contaminants, and fix the remaining in place in preparation for protective storage or permanent disposal work activities. Decontamination may be carried out using chemical, electrochemical, and mechanical means. Like materials, humans may also be contaminated with CBRN contamination. Changes in cellular function can occur at lower radiation doses and exposure to chemicals. At high dose, cell death may take place. Therefore, decontamination of humans at the time of emergency while generating bare minimum waste is an enormous task requiring dedication of large number of personnel and large amount of time. General principles of CBRN decontamination are discussed in this review with emphasis on radiodecontamination.

Crevice corrosion properties of 304 Stainless Steel (304SS) and Alloy 600 in aqueous oxalic acid solution were evaluated and the results were analyzed by chemical thermodynamic calculation. The corrosion rate of 304SS in the low pH region was highly accelerated, however that of Alloy 600 was not. Crevice corrosion resistance of those alloys critically relies on the formation of protective layer (NiCO) which was formed on the surface of Alloy 600 only. FeCO did not contribute to corrosion resistance which was formed on the surface of 304SS at the low pH region. [ABSTRACT FROM AUTHOR]

The Kori-1 nuclear power plant (NPP), a Westinghouse 2-loop pressurized water reactor in Korea, permanently ceased operations on June 18, 2017. Before the main decommissioning activities, full chemical decontamination of primary systems will be performed to secure the safety of workers and minimize the quantity of radioactive waste. In this study, the steady and transient flow characteristics for the chemical decontamination operations were analyzed via a simulation using the Multidimensional Analysis of Reactor Safety, KINS Standard version. Then, based on the accumulated flow mass released from the reactant cooling systems during transient events, the radioactivity levels were estimated using the oxide layer removal ratio obtained from the chemical decontamination experiment. The loss of residual heat removal, steam generator tube rupture (SGTR), power-operated relief valve open (PORV Open), and combination of SGTR and PORV Open simulations were investigated in terms of the transient events. Finally, a strategy for managing transient events during the full-system chemical decontamination operation of the Kori-1 NPP is proposed. [ABSTRACT FROM AUTHOR]

Abstract: Poultry products are highly perishable with a short shelf-life of approximately 4–5 days. Chemical treatments have the potential to inhibit microbial spoilage and extend shelf-life. Preliminary tests were carried out on broiler skin samples in the laboratory and the most promising treatments tested on carcasses in the broiler processing plant. In the laboratory, the immediate and storage (3 days at 4 °C) effect of trisodium phosphate (TSP, 10 & 14%, w/v), lactic acid (LA, 1 & 5% v/v), citric acid (CA, 1 & 5%, w/v), peroxyacids (POA, 100 & 200ppm) and acidified sodium chlorite (ASC, 500 & 1,200ppm) on TVC (mesophiles and psychrotrophs), Enterobacteriaceae, Pseudomonas, lactic acid bacteria and yeasts/moulds were investigated. In general, TSP and CA were the most effective immediate treatments and in the broiler processing plant, the effect of dipping and spraying carcasses with these chemicals on microbial shelf-life was examined over 15 days at 4 °C. Although a significant (P < 0.05) immediate reduction in TVC (mesophiles and psychrotrophs) was observed with TSP in the laboratory experiment, there was no further inhibition and after 3 days the treated and control samples had similar counts. The organic acids also caused a significant (P < 0.05) immediate reduction in TVC (mesophiles and psychrotrophs) but, in contrast to TSP, a mild inhibition of subsequent growth was also observed. In the processing plant, a microbial shelf-life of approximately 4 days was obtained at 4 °C on the control (water-treated) samples which was extended by 1–2 days after treatment with TSP (14%, dip) and by up to 4 days with CA (5%, dip). It was concluded that the microbial quality and microbial shelf-life of poultry may be considerably enhanced using selective chemical treatments. [Copyright &y& Elsevier]