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The severe outbreak of respiratory coronavirus disease 2019 has increased the significant demand of respiratory mask and its use become ubiquitous worldwide to control this unprecedented respiratory pandemic. The performance of a respiratory mask depends on the efficiency of the filter layer which is mostly made of polypropylene melt blown non-woven (PP-MB-NW). So far, very limited characterization data are available for the PPE-MB-NW in terms to achieve desired particulate filtration efficiency (PFE) against 0.3 µm size, which are imperative in order to facilitate the right selection of PP-MB-NW fabric for the development of mask. In present study, eight different kinds of PP-MB-NW fabrics (Sample A–H) of varied structural morphology are chosen. The different PP-MB-NW were characterized for its pore size and distribution by mercury porosimeter and BET surface area analyzer was explored first time to understand the importance of blind pore in PFE. The PP-MB-NW samples were characterized using scanning electron microscopy so as to know the surface morphology. The filtration efficiency, pressure drop and breathing resistance of various PP-MB-NW fabric samples are investigated in single and double layers combination against the particle size of 0.3, 0.5 and 1 µm. The samples which are having low pore dia, high solid fraction volume, and low air permeability has high filtration efficiency (> 90%) against 0.3 µm particle with high pressure drop (16.3–21.3 mm WC) and breathing resistance (1.42–1.92 mbar) when compared to rest of the samples. This study will pave the way for the judicial selection of right kind of filter layer i.e., PP-MB-NW fabric for the development of mask and it will be greatly helpful in manufacturing of mask in this present pandemic with desired PFE indicating considerable promise for defense against respiratory pandemic.

Technological advancements in the field of chemical threat have made it possible to create extremely dangerous chemical warfare agents (CWA). Hence, the effective protection of personnel is very important in a chemical warfare scenario amidst the current climate of terrorism awareness. In particular, body protection plays a substantial role in the chemical defence considering the urgency of situation in the nuclear, biological and chemical environment. Activated carbon spheres (ACS) based permeable chemical protective clothing (coverall) was developed for protection against CWA. The adsorbent material i.e, ACS used in this protective clothing provided higher adsorption capacity (1029 mg/g in terms of iodine) and low thermal burden (34 °C WBGT index) compared to earlier indigenously developed NBC suit. This article focuses on the extensive evaluation of chemical protective clothing against sulfur mustard (HD), a CWA. The results revealed that the developed protective clothing provided more than 24 h protection against HD. This chemical protective suit is light weight (< 2.75 kg for XL size). It also has higher air permeability (> 30 cm3/s/cm2) as well as less water vapour resistance (< 9.6 m2Pa/W). With continued innovations in materials and attention to key challenges it is expected that advanced, multifunction chemical protective suit will play a pivotal role in the CWA protection scenario.

Background Insecticidal fabrics are important personal protective measures against mosquitoes, ticks and other disease vectors. In the absence of internationally accepted guidelines, bioefficacy tests have been carried out using continuous exposure and three minutes exposure bioassay methods. Recently, we have reported an improved method for bioefficacy testing of insecticidal fabrics, which involves continuous exposure of mosquitoes to the test fabrics. The present paper reports the comparative evaluation of the outcomes of the continuous exposure bioassay and the three minutes bioassay on the same fabric samples. Methods Permethrin content in the treated fabric samples was determined through HPLC analysis and NMR studies were performed to establish the stability of the analyte. Bioefficacy tests were carried out against dengue vector Aedes aegypti and malaria vector Anopheles stephensi as per the improved test method and the three minutes bioassay method. Results The permethrin doses in the fabric samples ranged from 60 to 3000 mg/m 2 and 36.2% of permethrin was retained after 10 washings. The extraction and chromatographic analysis were not found to affect the stability of permethrin. In continuous exposure, all fabric samples showed bioefficacy, as the mean complete knockdown time for both Ae. aegypti (10.5–34.5 min) and An. stephensi (14.5–36.8 min) was ≤ 71.5 min. The same samples were found to be not effective when tested using the three minutes bioassay method, since the knockdown and mortality percentages were well below the required bioefficacy values. The bioefficacy of the fabric samples in terms of complete knockdown time was significantly higher against Ae. aegypti in comparison to An. stephensi . The mean complete knockdown time of Ae. aegypti increased to 48.3 min after 10 washings indicating a significant reduction in bioefficacy. Conclusions Bioefficacy testing of the insecticidal fabrics using the improved method resulted in outcomes, which could be correlated better with the permethrin content in the fabric samples. The improved method is more appropriate for the testing of insecticidal fabrics than the three minutes bioassay method. Further evaluation of the improved method using different test arthropods could help in the formulation of specific guidelines for the bioefficacy testing of insecticidal fabrics.

A three-layered composite wipe was fabricated by laminating individual layers of non-woven polypropylene, activated carbon fabric (ACF) and aramid fabric for the sampling and investigation of chemical warfare agents (CWA)-contaminated urban porous and non-porous surfaces. The material of main ACF layer was characterized to ascertain its suitability to act as an efficient adsorbent for the surface wipe sampling. The performance of ACF-based composite wipe was determined by evaluating its extraction efficiency, wiping efficacy and adsorption capacity for the sampling of blister and nerve agent class of CWA-contaminated surfaces using gas chromatography-mass spectrometry (GC-MS). Parameters like amount of wipe required, solvent selection, amount of solvent, time of extraction etc. were optimized to achieve the maximum recovery of contaminating analytes required for the forensic investigations. Overall recoveries of contaminating analytes after sampling and extraction were found to be in the range of 45–85% for all types of surfaces. No breakthrough in wiping process was noticed up to contamination density (CD) 1.6 mg/cm2 for non-porous surface and 3.2 mg/cm2 for porous surfaces. ACF-based wipe was found capable to significantly reduce the vapour hazards from liquid sulphur mustard (HD) and sarin (GB). Contamination from surfaces could be preserved within the wipe up to 15 days for the extended forensic investigation purposes. Limit of detections (LOD) of contaminants was determined in the range of 0.8–6.8 ng/cm2 while limit of quantitation (LOQ) was achieved up to the range of 2.4–14.4 ng/cm2 for wipe sampling of different surfaces.

Chemical warfare agents (CWAs) are extremely lethal substances used in warfare and terrorism, capable of causing permanent damage even in small doses, despite medical intervention. Therefore, detection, protection, and detoxification of CWAs are vital for the safety of first responders, military personnel, and civilians, driving significant research in this area. Herein, we designed and synthesized a poly(diallyldimethylammonium chloride) (PDDA) mediated cupric oxide (CuO) functionalized activated carbon fabric (ACF), termed ACF@PDDA-CuO, as an adsorbent filter material for self-detoxifying chemical protective clothing. PDDA, a positively charged polyelectrolyte, effectively binds in-situ synthesized CuO to the negatively charged ACF surface, serving as a suitable binder. This study demonstrates the synergistic effects of PDDA-CuO functionalization on ACF, where PDDA treatment enhanced mechanical and comfort properties, and CuO crystal growth significantly improved detoxification efficacy against the CWA Nerve Agent Sarin. Comprehensive analyses, including FTIR, BET surface area analysis, SEM, EDS, TEM, STEM, TGA, XPS, and XRD, confirmed the uniform deposition of CuO and PDDA on the ACF surface. The Cu content on ACF@PDDA-CuO samples was measured via iodometric titration. The materials were evaluated for tensile strength, air permeability, water vapor permeability, nerve agent (Sarin) detoxification, and blister agent (Sulfur Mustard) breakthrough time to assess their applicability for protective clothing. The optimized PDDA-CuO on ACF detoxified 82.04% of Sarin within 18 h, compared to 25.22% by ACF alone, and enhanced tensile strength by 23.67%, air permeability by 24.63%, and water vapor permeability by 3.94%, while maintaining protection against Sulfur Mustard for 24 h. These findings indicate that ACF@PDDA-CuO is a promising candidate for CWA protective clothing, offering robust protection with enhanced comfort. [Display omitted]

Activated carbon fabric or fiber (ACF) is a novel carbonaceous material with exceptionally high adsorption rate and larger adsorption capacity, that has emerged as a rising star in the field of adsorbents. ACF has many advantages over other commercial porous storage materials such as granular activated carbon and powdered activated carbon in terms of adsorption capacity, well defined microporous structure, stability, flexibility and ease of lamination to various substrates. In the last few years, activated carbon fabrics have gained greater choice of interest for use as an adsorbent material in several fields including nuclear, biological and chemical (NBC) protection suit. Viscose rayon, acetate, polyacrylonitrile, pitch, and phenolic based materials are mainly used as precursors for preparation of ACF. ACF or fibres are generally prepared by process comprising stabilisation, carbonisation and activation of precursors. Reviews recent advances and developments in the field of ACF and their utility as an adsorbent material in various fields including NBC scenario. ACF with unmatchable pore structure and surface characteristics at present, with continued innovations and attention to its key challenges, it is expected that ACF will play a pivotal role in diverse environmental, defence, and civil applications.

The safety profile of COVID-19 vaccines is understudied in patients with systemic sclerosis (SSc). We compared short-term adverse events (AEs) 7 days following vaccination in patients with SSc vs other rheumatic (AIRDs), non-rheumatic autoimmune diseases (nrAIDs), and healthy controls (HCs). The COVID-19 Vaccination in autoimmune diseases (COVAD) self-reporting e-survey was circulated by a group of > 110 collaborators in 94 countries from March to December 2021. AEs were analyzed between different groups using regression models. Of 10,679 complete respondents [73.8% females, mean age 43 years, 53% Caucasians], 478 had SSc. 83% had completed two vaccine doses, Pfizer-BioNTech (BNT162b2) (51%) was the most common. Minor and major AEs were reported by 81.2% and 3.3% SSc patients, respectively, and did not differ significantly with disease activity or different vaccine types, though with minor symptom differences. Frequencies of AEs were not affected by background immunosuppression, though SSc patients receiving hydroxychloroquine experienced fatigue less commonly (OR 0.4; 95% CI 0.2–0.8). Frequency of AEs and hospitalisations were similar to other AIRDs, nrAIDs, and HC except a higher risk of chills (OR 1.3; 95% CI 1.0–1.7) and fatigue (OR 1.3; 95% CI 1.0–1.6) compared to other AIRDs. COVID-19 vaccines were largely safe and well tolerated in SSc patients in the short term. Background immunosuppression and disease activity did not influence the vaccination-related short-term AEs.