By definition, the nonthermal plasma (NTP) is partially ionized gas where the energy is stored mostly in the free electrons and the overall temperature remains low. NTP is widely used for many years ...in various applications such as low-temperature plasma chemistry, removal of gaseous pollutants, in gas-discharge lamps or surface modification. However, during the last ten years, NTP usage expanded to new biological areas of application like plasma microorganisms' inactivation, ready-to-eat food preparation, biofilm degradation or in healthcare, where it seems to be important for the treatment of cancer cells and in the initiation of apoptosis, prion inactivation, prevention of nosocomial infections or in the therapy of infected wounds. These areas are presented and documented in this paper as a review of representative publications.
This study investigates the effects of five decontamination methods on the filter quality (qf) of three commercially available electret masks-N95, Gauze and Spunlace nonwoven masks. Newly developed ...evaluation methods, the overall filter quality (qf,o) and the qf ratio were applied to evaluate the effectiveness of decontamination methods for respirators. A scanning mobility particle sizer is utilized to measure the concentration of polydispersed particles with diameter 14.6-594 nm. The penetration of particles and pressure drop (Δp) through the mask are used to determine qf and qf,o. Experimental results reveal that the most penetrating particle size (MPS) for the pre-decontaminated N95, Gauze and Spunlace masks were 118 nm, 461 nm and 279 nm, respectively, and the respective penetration rates were 2.6%, 23.2% and 70.0%. The Δp through the pretreated N95 masks was 9.2 mm H2O at the breathing flow rate of heavy-duty workers, exceeding the Δp values obtained through Gauze and Spunlace masks. Decontamination increased the sizes of the most penetrating particles, changing the qf values of all of the masks: qf fell as particle size increased because the penetration increased. Bleach increased the Δp of N95, but destroyed the Gauze mask. However, the use of an autoclave reduces the Δp values of both the N95 and the Gauze mask. Neither the rice cooker nor ethanol altered the Δp of the Gauze mask. Chemical decontamination methods reduced the qf,o values for the three electret masks. The value of qf,o for PM0.1 exceeded that for PM0.1-0.6, because particles smaller than 100 nm had lower penetration, resulting in a better qf for a given pressure drop. The values of qf,o, particularly for PM0.1, reveal that for the tested treatments and masks, physical decontamination methods are less destructive to the filter than chemical methods. Nevertheless, when purchasing new or reusing FFRs, penetration should be regarded as the priority.
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•NPBC was synthesized from chemical pollutant (reactive red 2, RR2), urea and NaHCO3.•NPBC/PMS system exhibited excellent catalytic efficiency for sulfadiazine (SDZ) degradation.•NPBC ...exhibited excellent universality, adaptability, and reusability.•1O2 was the dominating active specie in NPBC/PMS system.•The biotoxicity of SDZ was evaluated by ECOSAR analysis and seeds germination tests.
Turning chemical wastes into valuable materials presently is a key challenge. Therefore, a facile method was employed upon synthesis of an N-doped porous biochar (NPBC) catalyst via pyrolysis of chemical pollutant (reactive red 2, RR2), urea, and NaHCO3. Using NaHCO3 activation, the NPBC/PMS system exhibited excellent catalytic efficiency for sulfadiazine (SDZ) degradation, which was attributed to the porous structure with abundant active species of graphitic C/N, C=O, –COOH, and C–S–C. Significantly, the NPBC displayed excellent environmental suitability, catalytic universality for the decomposition of common organic pollutants (i.e. bisphenol A, ciprofloxacin, tetracycline, and sulfamethoxazole) and catalytic recycling stability. In addition, free radical quenching and mechanism inspection demonstrated that 1O2 is the dominating reactive oxygen species (ROS) in the NPBC/PMS system. The most probable degradation pathway and mechanism are proposed. Finally, the biotoxicity of SDZ before and after degradation was evaluated by ECOSAR analysis and the germination tests of wheat seeds. This study not only provides a rational method for the facile synthesis of valuable materials from chemical pollutants, but also presents a direction for discovering metal-free catalysts with remarkable activity for water decontamination in the future.
Water‐only or water and soap are widely recommended as preferred solutions for dermal decontamination. However, limited efficacy data exist. We summarized experimental studies evaluating in vitro ...efficacy of water‐only or soap and water in decontaminating chemical warfare agents (CWA) or their simulants from human skin models. Embase, Covidence®, MEDLINE, PubMed, Web of Science, and Google Scholar were searched for articles using water‐only or soap and water decontamination methods for removal of CWA/CWA simulants in in vitro human skin models. Data extraction was completed from seven studies, yielding seven contaminants. Water‐only decontamination led to partial decontamination in all skin samples (100%, n = 81/81). Soap and water decontamination led to partial decontamination in all skin samples (100%, n = 143/143). Four studies found decontamination to either paradoxically enhance absorption of contaminants or their penetration rates, known as the “wash‐in” effect. Despite recommendations, water‐only or water and soap decontamination were found to yield partial decontamination of CWA or their simulants in all human in vitro studies. Thus, more effective decontaminating agents are needed. Some studies demonstrated increased or faster penetration of chemicals following decontamination, which could prove deadly for agents such as VX, although these findings require in vivo validation. Heterogeneity in experimental setups limits interstudy comparison, and it remains unclear when water‐only or water and soap are ideal decontaminants, which requires more studies. Pending manuscripts will summarize in vivo human and animal efficacy data. International harmonized efficacy protocol should enable more efficient public health decisions for evidence‐based public health decisions.
Water‐only or water and soap are widely recommended as preferred solutions for dermal decontamination. However, limited efficacy data exist, and they demonstrate water‐only or water and soap decontamination to yield partial decontamination of chemical warfare agents.
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