SARS-CoV-2 RNA Recovery from Air Sampled on Quartz Fiber Filters: A Matter of Sample Preservation?

The airborne route of transmission of SARS-CoV-2 was confirmed by the World Health Organization in April 2021. There is an urge to establish standardized protocols for assessing the concentration of SARS-CoV-2 RNA in air samples to support risk assessment, especially in indoor environments. Debates on the airborne transmission route of SARS-CoV-2 have been complicated because, among the studies testing the presence of the virus in the air, the percentage of positive samples has often been very low. In the present study, we report preliminary results on a study for the evaluation of parameters that can influence SARS-CoV-2 RNA recovery from quartz fiber filters spotted either by standard single-stranded SARS-CoV-2 RNA or by inactivated SARS-CoV-2 virions. The analytes were spiked on filters and underwent an active or passive sampling; then, they were preserved at −80 °C for different numbers of days (0 to 54) before extraction and analysis. We found a mean recovery of 2.43%, except for the sample not preserved (0 days) that showed a recovery of 13.51%. We found a relationship between the number of days and the recovery percentage. The results presented show a possible issue that relates to the quartz matrix and SARS-CoV-2 RNA recovery. The results are in accordance with the already published studies that described similar methods for SARS-CoV-2 RNA field sampling and that reported non-detectable concentrations of RNA. These outcomes could be false negatives due to sample preservation conditions. Thus, until further investigation, we suggest, as possible alternatives, to keep the filters: (i) in a sealed container for preservation at 4 °C; and (ii) in a viral transport medium for preservation at a temperature below 0 °C.This research was funded by University of Trieste Atheneum Fund for scientific research (2021) and IRCCS Burlo Garofolo (RC47/20)

Indoor air quality evaluation in oncology units at two European hospitals: Low-cost sensors for TVOCs, PM<inf>2.5</inf> and CO<inf>2</inf> real-time monitoring

IAQ assessment is a priority in oncology units where high air quality standards must be guaranteed to protect vulnerable patients. To fill the existing knowledge gap on IAQ in oncology units, extensive monitoring campaigns were performed inside two European oncology units (Bari in Italy, 24th February 2018–31st July 2019; Barcelona in Spain, 18th July-26th November 2018) for high temporal resolution monitoring of total volatile organic compounds (TVOCs), fine particulate matter (PM2.5), CO2 and other environmental parameters. Selected low-cost sensors (Corvus IAQ monitor, Speck, ZyAura CO2 monitor) were deployed. Laboratory and field inter-comparison of PM sensors with scientific-grade reference instruments was performed. TVOCs, PM2.5 and CO2 temporal profiles clearly show a regular weekday pattern with concentration peaks in daytime hours associated with higher human occupancy in the wards for scheduled chemotherapy treatments. Human occupancy (human emission and walking-induced particle resuspension), the administration of pharmaceutical products and the use of disinfectants and cleaning products predominantly affected TVOCs and PM2.5 concentrations in oncology wards. Although PM sensors showed low to moderate correlation with reference instruments (R2 = 0.34–0.66), this study provides additional evidence on their potential for inexpensive, real-time monitoring and detection of pollution events. Mitigation measures could be applied to improve IAQ in the investigated locations including more efficient scheduling, improved waiting room design and better ventilation strategies.The authors acknowledge the Oncology Institute Giovanni Paolo II I.R.C.C.S. in Bari (Italy) (Director Dr. Vito Antonio Delvino) and the Barcelona Pediatric Hospital (Mr. J. Medina). Moreover, special acknowledgements are for LabService Analytica srl (Dr. Antonio Fornaro) and the start-up Oscar by Energy for their precious assistance for the setting-up and the configuration of the integrated monitoring system at the oncology unit in Bari.Peer reviewe

Chemical characterization of ODOR active volatile organic compounds emitted from perfumes by GC/MS-O

The selection of proper compounds to include in perfumesâ\u80\u99 formulation is of particular interest for the perfume industry. Essential oils and perfumes are subject to quality control as well as to chemical characterization; therefore, GC/MS-O methodology can be considered a useful tool for research purposes and/or for improving industrial manufacturing processes. In this study, GC/MS-O methodology was applied to a commercial brand perfume and a natural-derived one, both characterized by a floral scent, with the main purpose of recognizing the odor active VOCs responsible of the characteristic and predominant notes. GC/MS-O analysis highlighted that sensory detection can be more efficient than the analytical one. Ocimene, α-Ionone and α-Isomethylionone were the most abundant odor compounds for the commercial-brand perfume, while β-Hydroxyethylbenzene was detected for the natural-derived one. Moreover, organic compounds of concern such as Toluene and Benzyl Alcohol were detected highlighting the need for quality control to reduce human risks for inhalation exposure and allergies

Total p-PAH Levels Nearby a Complex Industrial Area: A Tailored Monitoring Experiment to Assess the Impact of Emission Sources

In this study, data on the hourly concentrations of the total particle-bound Polycyclic Aromatic Hydrocarbons (p-PAHs) collected between 1 August 2013 and 31 August 2014 by the air quality fence monitoring network of the biggest European steel plant, were analyzed. In contrast with what was predicted, the total p-PAH concentration did not decrease with distance from the steel plant, and higher concentrations were registered at the Orsini site, in the urban settlement, relative to the Parchi site, which is nearest to the coke ovens. Therefore, in order to identify and explain the cause of these high concentrations, a tailored monitoring experiment was carried out on a specific monitoring pathway by using a total p-PAHs monitor placed onto a cart. The real-time monitoring of the total p-PAH concentration on the road revealed to be a useful tool, which identified vehicular traffic as an important source of p-PAHs and highlighted the possible high short-term effect that vehicular traffic sources could have on the health of the exposed human population. Moreover, the study focused attention on the importance of the spatial representativeness of fixed monitoring stations, especially in a highly complex industrial area such as Taranto (Southern Italy)

Temporal variation of VOC emission from solvent and water based wood stains

Solvent- and water-based wood stains were monitored using a small test emission chamber in order to characterize their emission profiles in terms of Total and individual VOCs. The study of concentration-time profiles of individual VOCs enabled to identify the compounds emitted at higher concentration for each type of stain, to examine their decay curve and finally to estimate the concentration in a reference room. The solvent-based wood stain was characterized by the highest Total VOCs emission level (5.7mg/m3) that decreased over time more slowly than those related to water-based ones. The same finding was observed for the main detected compounds: Benzene, Toluene, Ethylbenzene, Xylenes, Styrene, alpha-Pinene and Camphene. On the other hand, the highest level of Limonene was emitted by a water-based wood stain. However, the concentration-time profile showed that water-based product was characterized by a remarkable reduction of the time of maximum and minimum emission: Limonene concentration reached the minimum concentration in about half the time compared to the solvent-based product. According to AgBB evaluation scheme, only one of the investigated water-based wood stains can be classified as a low-emitting product whose use may not determine any potential adverse effect on human health

Evaluation of Second-Hand Exposure to Electronic Cigarette Vaping under a Real Scenario: Measurements of Ultrafine Particle Number Concentration and Size Distribution and Comparison with Traditional Tobacco Smoke

The present study aims to evaluate the impact of e-cig second-hand aerosol on indoor air quality in terms of ultrafine particles (UFPs) and potential inhalation exposure levels of passive bystanders. E-cig second-hand aerosol characteristics in terms of UFPs number concentration and size distribution exhaled by two volunteers vaping 15 different e-liquids inside a 49 m3 room and comparison with tobacco smoke are discussed. High temporal resolution measurements were performed under natural ventilation conditions to simulate a realistic exposure scenario. Results showed a systematic increase in UFPs number concentration (part cm&minus;3) related to a 20-min vaping session (from 6.56 &times; 103 to 4.01 &times; 104 part cm&minus;3), although this was one up to two order of magnitude lower than that produced by one tobacco cigarette consumption (from 1.12 &times; 105 to 1.46 &times; 105 part cm&minus;3). E-cig second-hand aerosol size distribution exhibits a bimodal behavior with modes at 10.8 and 29.4 nm in contrast with the unimodal typical size distribution of tobacco smoke with peak mode at 100 nm. In the size range 6&ndash;26 nm, particles concentration in e-cig second-hand aerosol were from 2- (Dp = 25.5 nm) to 3800-fold (Dp = 9.31 nm) higher than in tobacco smoke highlighting that particles exhaled by users and potentially inhaled by bystanders are nano-sized with high penetration capacity into human airways

Chemical characterization of electronic cigarette (e-cigs) refill liquids prior to EU tobacco product directive adoption: Evaluation of BTEX contamination by HS-SPME-GC-MS and identification of flavoring additives by GC-MS-O

The present study focused on the determination of benzene, toluene, ethylbenzene and xylenes (BTEX) concentration levels in 97 refill liquids for e-cigs selected by the Italian National Institute of Health as representative of the EU market between 2013 and 2015 prior to the implementation of the European Union (EU) Tobacco Product Directive (TPD). Most of the e-liquids investigated (85/97) were affected by BTEX contamination, with few exceptions observed (levels below the limit of quantification (LOQ) of headspace-solid phase micro extraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) methodology). Across brands, concentration levels ranged from 2.7 to 30,200.0 μg/L for benzene, from 1.9 to 447.8 μg/L for ethylbenzene, from 1.9 to 1,648.4 μg/L for toluene and from 1.7 to 574.2 μg/L for m, p, o-xylenes. The variability observed in BTEX levels is likely to be related to the variability in contamination level of both propylene glycol and glycerol and flavoring additives included. No correlation was found with nicotine content. Moreover, on a limited number of e-liquids, gas chromatography-mass spectrometry-olfactometry (GC-MS-O) analysis was performed, allowing the identification of key flavoring additives responsible of specific flavor notes. Among them, diacetyl is a flavoring additive of concern for potential toxicity when directly inhaled into human airways. The data reported are eligible to be included in the pre-TPD database and may represent a reference for the ongoing evaluation on e-liquids safety and quality under the current EU Legislation

Breath Analysis: A Systematic Review of Volatile Organic Compounds (VOCs) in Diagnostic and Therapeutic Management of Pleural Mesothelioma

Malignant pleural mesothelioma (MPM) is a rare neoplasm related to asbestos exposure and with high mortality rate. The management of patients with MPM is complex and controversial, particularly with regard to early diagnosis. In the last few years, breath analysis has been greatly implemented with this aim. In this review the strengths of breath analysis and preliminary results in searching breath biomarkers of MPM are highlighted and discussed, respectively. Through a systematic electronic literature search, collecting papers published from 2000 until December 2018, fifteen relevant scientific papers were selected. All papers considered were prospective, comparative, observational case-control studies although every single one pilot and based on a relatively small number of samples. The identification of diagnostic VOCs pattern, through breath sample characterization and the statistical data treatment, allows to obtain a strategic information for clinical diagnostics. To date the collected data provide just preliminary information and, despite the promising results and diagnostic accuracy, conclusions cannot be generalized due to the limited number of individuals included in each cohort study. Furthermore none of studies was externally validated, although validation process is a necessary step towards clinical implementation. Breathomics-based biomarker approach should be further explored to confirm and validate preliminary findings and to evaluate its potential role in monitoring the therapeutic response