Fabric Masks as a Personal Dosimeter for Quantifying Exposure to Airborne Polycyclic Aromatic Hydrocarbons

Wearable sampling of proteins from human exhaled aerosols for nano-liquid chromatography-tandem mass spectrometry analysis: A pilot study

RATIONALE

Human exhaled breath usually contains unique proteins that may provide clues to characterize individual physiological activities and many diseases. However, the concentration of exhaled proteins in exhaled breath is extremely low and usually does not reach the detection limits of all online breath mass spectrometry instruments. Therefore, developing a new breath sampler for collecting and characterizing exhaled proteins is important.

METHODS

In this study, a new mask-based wearable sampler was developed by fixing metal materials into the inner surface of the KN95 mask. Human exhaled proteins could be directly adsorbed onto the metal material while wearing the mask. After sampling, the collected proteins were eluted, digested, and identified using nano-liquid chromatography-tandem mass spectrometry (nano-LC-MS/MS).

RESULTS

The adsorption of exhaled proteins was evaluated, showing that modified gold foil is an effective material for collecting exhaled proteins. Various endogenous proteins were successfully identified from exhaled breath, many of which can be potential biomarkers for disease diagnosis.

CONCLUSIONS

By coupling the newly developed mask sampler with nano-LC-MS/MS, human exhaled proteins were successfully collected and identified. Our results show that the mask sampler is wearable, simple, and convenient, and the method is noninvasive for investigating disease diagnosis and human health.

Aristolochic Acid Exposure via Dermal Contact or Inhalation of Herbal Powders: Evidence of Occupational Exposure in Herbalists with Urothelial Cancer

Emerging evidence showing urothelial cancer in herbalists is linked to aristolochic acid (AA) exposure; however, the exposure pathway remains unclear. Here, we show that dermal contact and inhalation of fine powders of AA-containing herbs are significant occupational AA exposure pathways for herbalists. We initiated the study by quantifying the amount of AA in the AA-containing powder deposited on gloves and face masks worn by the operators of an AA-containing herb grinding machine. Then, we measured the kinetics of dermal absorption and dissolution of AA from fine powders of AA-containing herbs into artificial sweat and surrogate lung fluid. Lastly, we quantified the mutagenic AA-DNA adduct levels formed in the kidneys of mice exposed to AA-containing fine powders through dermal contact. Our findings highlight an urgent occupational risk that should demand implementation of safety standards for herbalists exposed to AA-containing fine powders.

Face mask as an indicator and shield of human exposure to traditional and novel organophosphate esters

Herein, the trapping effectiveness of N95, filter KN95, medical surgical masks (MSMs), and disposable medical masks (DMMs) against 19 airborne traditional and novel organophosphate esters (OPEs) was evaluated. Laboratory simulations (n = 24 for each type of mask) showed that time-dependent accumulation of ∑19OPEs on the four types of masks ranged between 30.1 and 86.6 ng in 24 h, with the highest and lowest median amounts trapped by the N95 masks (53.3 ng) and DMMs (43.2 ng), respectively. The trapping efficiency of the four types of masks for ∑19OPEs decreased over time from 84 % to 39 % in 24 h, with N95 masks showing the highest median efficiency (70 %). Further, field investigations were conducted in five types of microenvironments (train, hospital, bus, supermarket, and canteen), and an analysis of 200 samples showed that ∑19OPEs were accumulated in the masks with a variable amount from 3.7 to 117 ng/mask. Consistent with the laboratory simulations, the N95 masks (29.0 ng/mask) exhibited the highest hourly median amount of trapped OPEs, followed by the KN95 masks (24.5 ng/mask), MSMSs (17.4 ng/mask), and DMMs (15.8 ng/mask). Triethyl phosphate (TEP), tris(1-chloro-2-propyl) phosphate (TCIPP), tri-n-butyl phosphate (TNBP), and cresyl diphenyl phosphate (CDP) as well as 4-isopropylphenyl diphenyl phosphate (4IPPDPP) and 2,4-diisopropylphenyl diphenyl phosphate (24DIPPDPP) were the most commonly detected traditional and novel OPEs. Based on the amount of OPEs trapped on the masks, we estimated the concentration of ∑19OPEs in the train microenvironment to be the highest (222 ng/m3), which is approximately 2-5 times higher than that in the other microenvironments. The results of this study prove that masks can effectively protect humans from exposure to OPEs and act as low-cost indicators of indoor contamination.

Face Mask as a Versatile Sampling Device for the Assessment of Personal Exposure to 54 Toxic Compounds in Environmental Tobacco Smoke

Exposure to environmental tobacco smoke (ETS), which contains hundreds of toxic compounds, significantly increases the risk of developing many human diseases, including lung cancer. The most common method of assessing personal exposure to ETS-borne toxicants is by sampling sidestream smoke generated by a smoking machine through a sorbent tube or filter, followed by solvent extraction and instrumental analysis. However, the ETS sampled may not truly represent the ETS in the ambient environment, due to complicating factors from the smoke released by the burning end of the cigarette and from the absorption of the chemicals in the respiratory tract of the smoker. In this study, we developed and validated an alternative air sampling method involving breathing through a face mask to simultaneously determine personal exposure to 54 ETS-borne compounds, including polycyclic aromatic hydrocarbons, aromatic amines, alkaloids, and phenolic compounds in real smoking scenarios. The newly developed method was used to evaluate the risk associated with exposure to ETS released from conventional cigarettes (CCs) and that from novel tobacco products such as e-cigarettes (ECs) and heated tobacco products (HTPs), with the observation of cancer risk associated with exposure to ETS released from CCs significantly higher than that from ECs and HTPs. It is anticipated that this method offers a convenient and sensitive way to collect samples for assessing the health impacts of ETS exposure.

Mask device as a new wearable sampler for breath analysis: what can we expect in the future?

Human exhaled breath is becoming an attractive clinical source as it is foreseen to enable noninvasive diagnosis of many diseases. Because mask devices can be used for efficiently filtering exhaled substances, mask-wearing has been required in the past few years in daily life since the unprecedented COVID-19 pandemic. In recent years, there is a new development of mask devices as new wearable breath samplers for collecting exhaled substances for disease diagnosis and biomarker discovery. This paper attempts to identify new trends in mask samplers for breath analysis. The couplings of mask samplers with different (bio)analytical approaches, including mass spectrometry (MS), polymerase chain reaction (PCR), sensor, and others for breath analysis, are summarized. The developments and applications of mask samplers in disease diagnosis and human health are reviewed. The limitations and future trends of mask samplers are also discussed.

Determination and risk assessment of phthalates in face masks. An Italian study

Serious human health concerns have been recently raised from daily use of face masks, due to the possible presence of hazardous compounds as the phthalic acid esters (PAEs). In this study, the content of 11 PAEs in 35 commercial masks was assessed by applying a specific and accurate method, using Gas Chromatography/Mass Spectrometry. Surgical, FFP2 and non-surgical models, for both adults and children were collected from the Italian market. Analyses showed that four of the target analytes were detected in all tested samples with median total concentrations ranging between 23.6 mg/kg and 54.3 mg/kg. Results obtained from the experimental analysis were used in the risk assessment studies carried out for both carcinogenic and non-carcinogenic effects. Doses of exposure (D_exp) of PAEs ranged from 6.43 × 10^-5 mg/kg bw/day to 1.43 × 10^-2 mg/kg bw/day. Cumulative risk assessment was performed for non-carcinogenic and carcinogenic effects. No potential risk was found for non-carcinogenic effects, yet the 20% of the mask samples showed potential carcinogenic effects for humans. A refined exposure assessment was performed showing no risk for carcinogenic effects. This paper presents a risk assessment approach for the identification of potential risks associated to the use of face masks.

Novel miniaturized passive sampling devices based on liquid phase microextraction equipped with cellulose-grafted membranes for the environmental monitoring of phthalic acid esters in natural waters

Phthalic acid esters (PAEs) are considered endocrine disruptors and potential carcinogens. Consequently, efficient and accurate environmental monitoring of trace levels of these organic pollutants is necessary to protect the population against their hazardous effects. Passive sampling techniques have gained notoriety for environmental monitoring and have been proven highly sensitive to temporal variations. This study developed a miniaturized passive sampling device (MPSD) based on hollow fiber liquid-phase microextraction (HF-LPME). The devices were calibrated in the laboratory using an automated calibration system. The results demonstrated the first-order uptake ranges for Diethyl phthalate (DEP), Diisobutyl phthalate (DiBP), Dibutyl phthalate (DBP), Benzyl butyl phthalate (BBP) and Bis(2-ethylhexyl phthalate) (DEHP) between 30 min and 24 h with sampling rates equivalent to 0.009; 0.021; 0.033; 0.085 and 0.003 mL h^-1 respectively (R² between 0.88 and 0.99). The calibrated devices were deployed in 12 marginal lagoons, stretching approximately 330 km along the main river. The extracts recovered from the devices were analyzed by gas chromatography (GC), resulting in the identification and quantification of DEP (0.697-13.7 ng L^-1), DiBP (0.100-4.43 ng L^-1), DBP (0.014-1.21 ng L^-1), BBP (0.218-5.67 ng L^-1), and DEHP (0.002-2.24 ng L^-1). Despite being frequently identified, DEHP concentrations were well below the maximum established limits, revealing a good water quality in terms of the target PAEs. In contrast, screening the extracts using GCxGC was possible to detect other hazardous pollutants such as pesticides, drugs, and their metabolites. The described device was effective and reliable, providing accurate PAE measurements following short exposure periods. In this sense, its deployment during emergency operations, such as accidental discharges of industrial effluents into natural waters, could continuously and cost-effectively monitor water quality.

Polyurethane Foam Face Masks as a Dosimeter for Quantifying Personal Exposure to Airborne Volatile and Semi-Volatile Organic Compounds

Airborne volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs) are commonly quantitated by collecting the analytes on solid sorbent tubes or passive air samplers, followed by solvent extraction and instrumental analysis, or by grab bag/canister measurements. We report herein a user-friendly sampling method by breathing through polyurethane foam (PUF) face masks to collect airborne VOCs and SVOCs for chemical analysis. Specifically, dibasic esters, phthalate esters, polycyclic aromatic hydrocarbons, linalool, and nicotine trapped on PUF masks were quantitated by gas chromatography-mass spectrometry analysis as model VOCs and SVOCs. Results showed that the amount of these model VOCs and SVOCs trapped on PUF masks is proportional to the exposure duration. After cross-validation by parallel sampling using XAD-2 packed sorbent tubes, the method was used to quantitate VOCs and SVOCs in a variety of indoor and outdoor environments with varying air concentrations of analytes, temperature, humidity, and wind speed. Because air pollution is considered a major cause of many human diseases and premature deaths and the developed PUF mask sampling method showed high trapping efficiencies for both VOCs and SVOCs, it is believed that the developed sampling method will find wide application in assessing air pollution-associated disease risks with possible extension to more classes of VOCs and SVOCs when coupled with suitable instrumental detection methods.

A pandemic-induced environmental dilemma of disposable masks: solutions from the perspective of the life cycle

The coronavirus disease 2019 (COVID-19) has swept the world and still afflicts humans. As an effective means of protection, wearing masks has been widely adopted by the general public. The massive use of disposable masks has raised some emerging environmental and bio-safety concerns: improper handling of used masks may transfer the attached pathogens to environmental media; disposable masks mainly consist of polypropylene (PP) fibers which may aggravate the global plastic pollution; and the risks of long-term wearing of masks are elusive. To maximize the utilization and minimize the risks, efforts have been made to improve the performance of masks (e.g., antivirus properties and filtration efficiency), extend their functions (e.g., respiration monitoring and acting as a sampling device), develop new disinfection methods, and recycle masks. Despite that, from the perspective of the life cycle (from production, usage, and discard to disposal), comprehensive solutions are urgently needed to solve the environmental dilemma of disposable masks in both technologies (e.g., efficient use of raw materials, prolonging the service life, and enabling biodegradation) and policies (e.g., stricter industry criteria and garbage sorting).

Recent Advances in Facemask Devices for In Vivo Sampling of Human Exhaled Breath Aerosols and Inhalable Environmental Exposures

Since the COVID-19 pandemic, the unprecedented use of facemasks has been requiring for wearing in daily life. By wearing facemask, human exhaled breath aerosols and inhaled environmental exposures can be efficiently filtered and thus various filtration residues can be deposited in facemask. Therefore, facemask could be a simple, wearable, in vivo, onsite and noninvasive sampler for collecting exhaled and inhalable compositions, and gain new insights into human health and environmental exposure. In this review, the recent advances in developments and applications of in vivo facemask sampling of human exhaled bacteria, viruses, proteins, and metabolites, and inhalable facemask contaminants and air pollutants, are reviewed. New features of facemask sampling are highlighted. The perspectives and challenges on further development and potential applications of facemask devices are also discussed.

Polyurethane-Based Face Mask as a Sampling Device for Environmental Tobacco Smoke

Environmental tobacco smoke (ETS), also known as secondhand smoking, contains human carcinogens associated with the development of many human diseases, including stroke, heart disease, leukemia, and lung cancer. Due to these adverse health effects, a sensitive and selective method is crucial for assessing the health impacts of ETS. While current methods to evaluate ETS exposure are either invasive or nonspecific and insensitive, in this study, we assessed the use of polyurethane foam face masks as a sampling medium to collect tobacco smoke-specific nicotine and nitrosamines for estimating personal exposure to ETS. This method was used in conjunction with tandem mass spectrometry coupled with isotope-dilution detection. After validation by comparison with the National Institute for Occupational Safety and Health standard method (NIOSH 2551) for nicotine, we quantitated ETS exposure in indoor and outdoor environments. The analysis shows the applicability of the method for monitoring nicotine down to ∼0.20 mg/m³ near an outdoor smoking hotspot and up to ∼5.2 mg/m³ in a room with burning cigarettes, all with a time resolution as short as 5 min. In comparison with the NIOSH method, the newly developed method is convenient, inexpensive, and does not require a personal sampling pump, thus can facilitate large-scale ETS exposure monitoring.

On the Flip Side of Mask Wearing: Increased Exposure to Volatile Organic Compounds and a Risk-Reducing Solution

Surgical masks have been worn by the public worldwide during the COVID-19 pandemic, yet hazardous chemicals in the petroleum-derived polymer layer of masks are currently ignored and unregulated. These organic compounds pose potential health risks to the mask wearer through dermal contact or inhalation. Here, we show that surgical masks from around the world are loaded with semivolatile and volatile organic compounds (VOCs), including alkanes, polycyclic aromatic hydrocarbons (PAHs), phthalate esters, and reactive carbonyls at ng to μg/mask levels. Naphthalene was the most abundant mask-borne PAH, accounting for over 80% of total PAH levels; acrolein, a mutagenic carbonyl, was detected in most of the mask samples, and di(2-ethylhexyl) phthalate, an androgen antagonist, was detected in one-third of the samples. Furthermore, there is large mask-to-mask variability of the residue VOCs, revealing the uneven quality of masks. We confirm that masks containing more residue VOCs lead to significantly higher exposure levels and associated disease risks to the wearer, which should warrant the attention of the general public and regulatory agencies. We find that heating the masks at 50 °C for as short as 60 min lowers the total VOC content by up to 80%, providing a simple method to limit our exposure to mask-borne VOCs.

Paper-in-Facemask Device for Direct Mass Spectrometry Analysis of Human Respiratory Aerosols and Environmental Exposures via Wearable Continuous-Flow Adsorptive Sampling: A Proof-of-Concept Study

Facemasks are considered safe and wearable devices that cover the human mouth and nose for filtering exhaled aerosols and inhaled environmental exposures; various chemical and environmental residues thus can remain in facemasks. Therefore, direct analysis of residues in facemasks can be used to investigate the wearer's health and behavior. Here, we developed a simple paper-in-facemask sampling method for adsorbing a wearer's respiratory aerosol and environmental exposures by fixing paper strips at the outside and inside surfaces of facemasks, and the paper strips were then analyzed by paper spray mass spectrometry (PSMS) for directly detecting adsorbed analytes without any sample pretreatment. The applicability of this device was demonstrated by directly analyzing exhaled aerosolized saliva, breath metabolites, and inhalable environmental exposures. The technical aspects, including sampling time, sampling position, paper property, and spray solvent, were investigated. The sampling process was revealed to involve a continuous-flow adsorptive mechanism. These findings motivated us to extend this work and build a wearable sampling device that is capable of simultaneously monitoring both exhaled and inhaled biomarkers in situ to investigate human health and environmental exposure. This work highlights that facemasks are promising platforms for aerosol collection and direct MS analysis, which is expected to be a promising method for monitoring human health, diseases, and behaviors.