Personal Exposure Monitoring Research Articles

Determination of subpicogram levels of airborne polycyclic aromatic hydrocarbons for personal exposure monitoring assessment

A method based on the use of GC coupled to Q-exactive Orbitrap mass spectrometry (GC-Orbitrap-MS) has been developed for the analysis of polycyclic aromatic hydrocarbons (PAHs) at sub-picogram levels. Outdoor ambient air particulate matter (PM2.5) and standard reference materials (SRM2260a) were analyzed in full scan mode showing low instrumental uncertainties (1–22%) and high linearity over a wide concentration range (0.5 pg and 500 pg/μL). Good reproducibility was obtained compared to the use of conventional single quadrupole GC–MS of PM samples. The quantification limit of the GC-Orbitrap-MS method for full scan analysis of PAHs in outdoor ambient air PM samples was 0.5 pg/μL. This low limit allowed the analysis of PAHs in samples collected with low volumes (< 0.5 m3), such as punch samples from whole filters or filter strips from personal exposure monitoring equipment. PAHs were successfully analyzed in filter strips from real-time Aethalometer AE51 equivalent black carbon (eBC) analyzers used in urban and rural sites, and in personal exposure monitors of firefighters during prescribed burns. The correlations between PAHs and eBC in these analyses were very strong (r2 ≥ 0.93). However, the equations obtained reflected the dominance of different emission sources, such as traffic in urban areas, wood burning for domestic heating, or wildfires. The method reported here affords the analyses of PAHs in high precision studies of atmospheric PM samples, e.g., high frequency sampling of low volumes, affording personal exposure monitoring assessments.

Characteristics of peak exposure to black carbon pollution in school, commute and home environments among school children in an urban community

Although real-time personal exposure monitoring devices have the ability to capture a wealth of data regarding fluctuations in pollutant levels, only a few studies have defined ‘peaks’ in black carbon (BC) exposure utilizing high-resolution data. Furthermore, studies to assess and characterize various features of peak exposure are very limited especially among children. A better understanding of characteristics of BC peak exposure would improve our understanding of health risks associated with BC. By capturing personal BC exposure at 5-min intervals using a real-time monitor during 24-hr monitoring periods among children in New York City (NYC), we defined ‘peak characteristics’ in 4 different ways across three major microenvironments (school vs. commute vs. home): 1) mean concentrations of BC across the 3 microenvironments, 2) ‘peak duration’ or time spent above the peak threshold (i.e., ≥1.5 μg/m3), 3) ‘peak intensity’ or the rate of exposure, defined as time spent above the threshold within each microenvironment divided by the total time spent in the microenvironment and 4) a novel metric of ‘peak variability’, defined as frequency of peaks (i.e., data points with +50% and −50% changes compared to the preceding and the subsequent data points), divided by the total time spent in the microenvironment. While peak duration was greatest at home, the intensity of peak exposure was greatest during commute hours, despite the short time spent in commute (p < 0.05). Peak variability was highest during commute, yet lowest in home environments (p < 0.05), particularly during non-sleeping hours. Children residing in a high-density urban setting spent on average, 5.4 hr per day above our peak threshold (≥1.5 μg/m3) in their everyday environments. Policies that limit children's exposure during high traffic periods and improved efforts to increase the number of vehicles using clean air technology could reduce the intensity of peaks and peak variability in children's BC exposure.

Personal exposure monitoring using GPS-enabled portable air pollution sensors: A strategy to promote citizen awareness and behavioral changes regarding indoor and outdoor air pollution.

Little is known about how individuals are exposed to air pollution in various daily activity spaces due to a lack of data collected in the full range of spatial contexts in which they spend their time. The limited understanding makes it difficult for people to act in informed ways to reduce their exposure both indoors and outdoors. This study aimed to (1) assess whether personalized air quality data collected using GPS-enabled portable monitors (GeoAir2), coupled with travel-activity diaries, promote people's awareness and behavioral changes regarding indoor and outdoor air pollution and (2) demonstrate the effect of places and activities on personal exposure by analyzing individual exposure profiles. 44 participants carried GeoAir2 to collect geo-referenced air pollution data and completed travel-activity diaries for three days. These data were then combined for spatial data analysis and visualization. Participants also completed pre- and post-session surveys about awareness and behaviors regarding air pollution. Paired-sample t-tests were performed to evaluate changes in knowledge, attitudes/perceptions, and behavioral intentions/practices, respectively. Lastly, follow-up interviews were conducted with a subset of participants. Most participants experienced PM2.5 peaks indoors, especially when cooking at home, and had the lowest exposure in transit. Participants reported becoming more aware of air quality in their surroundings and more concerned about its health effects (t = 3.92, p = 0.000) and took more action or were more motivated to alter their behaviors to mitigate their exposure (t = 3.40, p = 0.000) after the intervention than before. However, there was no significant improvement in knowledge (t = 0.897; p = 0.187). Personal exposure monitoring, combined with travel-activity diaries, leads to positive changes in attitudes, perceptions, and behaviors related to air pollution. This study highlights the importance of citizen engagement in air monitoring for effective risk communication and air pollution management.

Personal monitoring of fine particulate matter (PM2.5) exposure in mothers and young children in a South African birth cohort study – A pilot study

Air pollution is a recognized risk factor for impaired lung health and increased morbidity and mortality globally. Fine particulate matter (PM2.5) has been linked to respiratory illness, but assessing personal PM2.5 exposure remains difficult, especially in children. The MicroPEM™ and Enhanced Children's MicroPEM™ (ECM) are personal fine particulate matter exposure monitors that have not been well-evaluated for young children. We aimed to assess compliance and acceptability of these monitors and to investigate risk factors associated with fine particulate matter in mother-child pairs. MethodsMother-child pairs, enrolled in a South African birth cohort, the Drakenstein Child Health Study, were recruited. A MicroPEM (mother) and ECM (child), issued to each participant and worn over 24 h, quantified PM2.5 exposure. Home environment, wearability, and wearing compliance were assessed. Linear regression identified associations between variables characterising the home environment and PM2.5 levels. ResultsFrom August to November 2016, 86 mothers and 75 children (age 1–4 years) had results. Fossil fuels were used in 21% of homes; maternal smoking (37%) and exposure to household tobacco smoke (89%) was high. Waking wearing compliance of the devices was 59% in children and 56% in mothers. PM2.5 exposures were above the World Health Organization recommend 24-h interim target (IT-4 25 μg/m3) in 38/75 (51%) children, and in 44/86 (51%) mothers. Winter, smoking and public transport were associated with higher concentrations of PM2.5 in mothers. Whereas, for the children higher concentrations of PM2.5 were associated with winter and two or more household smokers; while lower concentrations were associated with age, weight-for-age z-score and households that had fewer than two basic dimensions. Wearability for children was reported as “very easy” in the majority (n = 54, 63%) with similar acceptability in mothers (n = 55, 64%). ConclusionThe MicroPEM and ECM provide wearable low-burden personal exposure monitoring tools for women and children with reasonable rates of acceptability. High exposure to fine particulate matter in children is concerning; strategies to minimise exposure need to be strengthened.

Second-hand Smoke Exposure Among Home Care Workers (HCWs) in Scotland.

Second-hand tobacco smoke (SHS) is a serious cause of ill-health, and concern around SHS exposure at work has driven legislation in public places. In Scotland, most workers are now protected from SHS at work. However, home care workers (HCWs) may still be exposed, as they enter private homes where smoking is unregulated. In this study, we aimed to understand the extent, duration and intensity of that exposure among HCWs in Lanarkshire, Scotland. We surveyed HCWs in four organisations involved in providing care at home: a public healthcare agency (NHS Lanarkshire), two local government entities and a private healthcare company. We also conducted personal exposure monitoring (PEM) of exposure to airborne nicotine and SHS-related fine particulate matter (PM2.5) with 32 HCWs. The vast majority of HCWs surveyed reported being exposed to SHS at work (395/537, 74%), and 50% of those who reported exposure in the home indicated daily exposure. We conducted PEM over 82 home visits, with 21% (17) demonstrating PM2.5 concentrations in excess of the WHO's 2010 air quality guideline limit for 24 h exposure. Duration of exposure to SHS tended to be short and as a result all nicotine samples were below the limit of quantification. Most HCWs are exposed to minimal levels of SHS at work. However, a minority may be exposed to concentrations which affect health. Policies to mitigate this exposure should be considered, such as the use of respiratory protective equipment, improved ventilation during visits, and interventions to reduce smoking in homes.

Updated findings from the International Nuclear Workers Study (INWORKS)

BACKGROUND Despite being a recognized carcinogen, public exposure to ionizing radiation has increased in recent decades. An update to the International Nuclear Workers Study (INWORKS) is being undertaken to strengthen direct assessments of the risks from low dose, low dose rate exposure to penetrating forms of ionizing radiation. Follow-up has been extended by 10 or more years in each partner country. METHODS We are conducting a pooled analysis of cohort mortality studies of nuclear industry workers in the United Kingdom, France, and the United States of America. Individual annual estimates of whole-body dose due to external exposure to penetrating radiation are derived from personal occupational exposure monitoring data. Vital status has been ascertained through 2012, 2014, and 2016 for workers in the United Kingdom, France, and the United States of America, respectively. RESULTS The updated pooled study includes 309,932 workers and 10.7 million person-years of observation. Over the period of follow-up, there have been 103,553 deaths observed, of which 31,009 are deaths due to cancer. CONCLUSIONS This presentation will describe the motivation for an update of the INWORKS study, the major aims of the project, and the progress that we have made to-date. We will report on a major update of this highly-influential study; the person-time in INWORKS increases by a factor of 1.3 and the number of cancer deaths increases by a factor of 1.6. The updated INWORKS analyses will provide some of the most informative direct estimates of low dose radiation risks reported to-date.

A large-scale personal monitoring of air pollution during pregnancy in the BiSC cohort

Background and aim: Large-scale monitoring of personal exposure to air pollution remains scarce, especially for pregnant women. We present the results of one of the largest monitoring campaigns of personal, home-indoor, and home-outdoor air pollution on pregnant women. Methods: The Barcelona Life Study Cohort (BiSC) is an ongoing cohort of 1086 mother-child pairs in Barcelona, Spain (2018 onwards). We monitored personal exposure to particulate matter &amp;#x2264; 2.5 µm (PM2.5; filter samples for chemical characterisation), Black Carbon (BC; MicroAeth AE51), and personal, home indoor and outdoor nitrogen dioxide (NO2; Gradko passive tubes) at first (week 12, w12) and third trimester (w32) of pregnancy. The Covid pandemic forced us to stop data collection on PM2.5 and BC. Results: Weekly averaged concentrations (for both w12 and w32) for NO2 were 28.5 &amp;#xb1; 12.0, 24.2 &amp;#xb1; 11.7, and 38.9 &amp;#xb1; 15.8 µg/m3 for personal exposure (N = 1680), indoors (N = 1685) and outdoors (N = 1570), respectively. Personal 48h average concentration was 21.0 &amp;#xb1; 15.7 µg/m3 for PM2.5 (N = 498) and 1.63 &amp;#xb1; 0.78 µg/m3 for BC (N = 374). Compared to current WHO 24-h outdoor air quality guidelines, 55.5% of PM2.5 samples and 89 % (outdoor) and 58.6% (personal) NO2 samples were above the recommendations (15 and 25 µg/m3, respectively). Correlations were higher between personal and indoor NO2 (spearman coefficient, r, &amp;#x3e;0.74) than between personal and outdoor (r &amp;#x3c;0.42) in both w12 and w32, due to a larger time spent at home (indoors). Moderate correlations between indoor and outdoor NO2 may be explained by potential indoor sources and indoor consumption of NO2 in gas-phase reactions. Conclusions: BiSC is one of the largest studies on air pollution exposure measurements on pregnant women. Participants were exposed to a wide range of air pollutants’ concentrations. Keywords: Pregnant women, Personal exposure assessment, Air Pollution

The use of snapshot personal exposure monitoring in estimating annual exposure to air pollutants for epidemiological studies

Background While advancements in sensor technology have broadened the use of personal monitors to estimate individual exposure to air pollution in recent years, significant challenges remain in extending their use for application in epidemiological studies. By collating measurements from several personal exposure (PE) campaigns in London, we aimed to develop a method for extending snapshot PE monitoring to estimates of annual mean exposure to pollution from outdoor sources at individual level. Methods Our conceptual model for annual extrapolation included three factors: a) variation in ambient concentrations, b) variation in infiltration efficiency of residence and other frequently inhabited buildings, and c) mobility behaviour. We utilised a dataset of 200+ million PE measurements from 427 participants of diverse demographics - school children, COPD patients, professional drivers and healthy adults - to characterise these three factors during snapshot monitoring (varying from four days to six months). Location-adjusted ambient concentrations, coupled with seasonal infiltration factors were used to extend results to annual mean personal exposure estimates for PM2.5, NO2, O3 and BC. Methods described elsewhere were used to censor exposure to indoor sources from the measurements. Results Residential infiltration factors did not show significant variation between seasons, suggesting that ventilation behaviour was not a major determinant. Each demographic exhibited distinct patterns in mobility behaviour, although impact was limited by relatively small proportion of time spent travelling. Behaviour modelling of participants with at least four months’ PE measurements showed that some participants had repeated routines, but others were unpredictable. Conclusions The extension of snapshot PE monitoring to annual mean exposure estimates requires assumptions relating to participant behaviour over time, notably mobility and residential ventilation. The impact of these assumptions will vary between individuals and demographics. Extrapolation of snapshot monitoring is more robust for those with predictable routines. Keywords Air pollution, personal exposure, sensors, measurement error

Personal air pollutant exposure monitoring in South African children in the VHEMBE birth cohort

The burden of disease associated with environmental exposures disproportionately impacts residents of low- and middle-income countries. Children living in rural regions of these countries may experience higher exposure to insecticides from indoor residual spraying used for malaria control and household air pollution. This study evaluated environmental exposures of children living in a rural region of South Africa. Quantifying exposure levels and identifying characteristics that are associated with exposure in this geographic region has been challenging due to limitations with available monitoring techniques. Wearable passive samplers have recently been shown to be a convenient and reliable tool for assessing personal exposures. In this study, a passive sampler wristband, known as Fresh Air wristband, was worn by 49 children (five-years of age) residing in the Limpopo province of South Africa. The study leveraged ongoing research within the Venda Health Examination of Mothers, Babies, and their Environment (VHEMBE) birth cohort. A wide range of chemicals (35 in total) were detected using the wristbands, including polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides, phthalates, and organophosphate esters (OPEs) flame retardants. Higher concentrations of PAHs were observed among children from households that fell below the food poverty threshold, did not have access to electric cookstoves/burners, or reported longer times of cooking or burning materials during the sampling period. Concentrations of p,p′-DDD and p,p′-DDT were also found to be elevated for children from households falling below the food poverty threshold as well as for children whose households were sprayed for malaria control within the previous 1.5 years. This study demonstrates the feasibility of using passive sampler wristbands as a non-invasive method for personal exposure assessment of children in rural regions of South Africa to complex mixtures environmental contaminants derived from a combination of sources. Future studies are needed to further identify and understand the effects of airborne environmental contaminants on childhood development and strategies to mitigate exposures.

Unencapsulated and washable two-dimensional material electronic-textile for NO2 sensing in ambient air

Materials adopted in electronic gas sensors, such as chemiresistive-based NO2 sensors, for integration in clothing fail to survive standard wash cycles due to the combined effect of aggressive chemicals in washing liquids and mechanical abrasion. Device failure can be mitigated by using encapsulation materials, which, however, reduces the sensor performance in terms of sensitivity, selectivity, and therefore utility. A highly sensitive NO2 electronic textile (e-textile) sensor was fabricated on Nylon fabric, which is resistant to standard washing cycles, by coating Graphene Oxide (GO), and GO/Molybdenum disulfide (GO/MoS2) and carrying out in situ reduction of the GO to Reduced Graphene Oxide (RGO). The GO/MoS2 e-textile was selective to NO2 and showed sensitivity to 20 ppb NO2 in dry air (0.05%/ppb) and 100 ppb NO2 in humid air (60% RH) with a limit of detection (LOD) of ~ 7.3 ppb. The selectivity and low LOD is achieved with the sensor operating at ambient temperatures (~ 20 °C). The sensor maintained its functionality after undergoing 100 cycles of standardised washing with no encapsulation. The relationship between temperature, humidity and sensor response was investigated. The e-textile sensor was embedded with a microcontroller system, enabling wireless transmission of the measurement data to a mobile phone. These results show the potential for integrating air quality sensors on washable clothing for high spatial resolution (< 25 cm2)—on-body personal exposure monitoring.

Network of low-cost air quality sensors for monitoring indoor, outdoor, and personal PM2.5 exposure in Seattle during the 2020 wildfire season

The increased frequency of wildfires in the Western United States has raised public awareness of the impact of wildfire smoke on air quality and human health. Exposure to wildfire smoke has been linked to an increased risk of cancer and cardiorespiratory morbidity. Evidence-driven interventions can alleviate the adverse health impact of wildfire smoke. During wildfires, public health guidance is based on regional air quality data with limited spatiotemporal resolution. Recently, low-cost air quality sensors have been used in air quality studies, given their ability to capture high-resolution spatiotemporal data. We demonstrate the use of a network of low-cost particulate matter (PM) sensors to gather indoor and outdoor PM2.5 data from seven locations in the urban Seattle area, along with a personal exposure monitor worn by a resident living in one of these locations during the 2020 Washington wildfire event. The data were used to determine PM concentration indoor/outdoor (I/O) ratios, PM reduction, and personal exposure levels. The result shows that locations equipped with high-efficiency particulate air (HEPA) filters and HVAC filtration systems had significantly lower I/O ratios (median I/O = 0.43) than those without air filtration (median I/O = 0.82). The median PM2.5 reduction for the locations with HEPA is 58% compared to 20% for the locations without HEPA. The outdoor PM sensor showed a high correlation to the nearby regional air quality monitoring stations (pre-calibration R2 = 0.92). The personal monitor showed higher variance in PM measurements as the user moved through different microenvironments and could not be fully characterized by the network of indoor or outdoor monitors. The findings imply that evidence-based interventions can be developed to reduce pollution exposure when combining data from indoor and outdoor sensors. Personal exposure monitoring captured temporal spikes in PM exposure.

Monitoring of polycyclic aromatic hydrocarbons emitted from kerosene fuel burning and assessment of health risks among women in selected rural and urban households of South India.

Polycyclic aromatic hydrocarbons (PAHs) are well-known hazardous substances; nevertheless, research on their exposure and health concerns associated with kerosene fuel emissions is limited. In this study, PAH (combined gaseous and particle phase) monitoring was carried out in the kitchen and living room in selected households. Personal exposure and cooking time monitoring were also carried out, simultaneously. The study's findings revealed that BaP, BA, BbF, and Nap were the most prevalent PAHs in both the summer and winter seasons, regardless of urban or rural households. The estimated values of average incremental lifetime cancer risks were found to be greater than the USEPA level, i.e., 1 × 10-6, in both urban and rural households, regardless of seasonal fluctuation. In both seasons, the non-carcinogenic risk for developmental and reproductive effects was higher in rural women than in urban women, and in case of developmental risk it showed greater than unity (rural: 1.11 and urban 1.03) in the winter season. On the other hand, Monte Carlo simulation model revealed that concentrations of PAHs (97.1% and 97.5%) and exposure duration (51.7% and 56.7%) were the most sensitive factors contributed for health risk estimations for urban and rural area in both seasons, respectively. Furthermore, the results clearly showed that women who were using kerosene for cooking were at a greater risk of acquiring both carcinogenic and non-carcinogenic health consequences from PAH exposure from kerosene cookstoves. It was recommended that they should utilize clean fuel, either by using LPG under the PMUY scheme or by using electricity/solar power to reduce health risks for better health.

Airborne nanoparticle analysis mini-system using a parallel-type inertial impaction technique for real-time monitoring size distribution and effective density

To elucidate the relationship between exposure to airborne nanoparticles (NPs; < 300 nm particles) and adverse health effects, two of their characteristics — size distribution and effective density— should be measured in real-time as they are key parameters that determine the particle deposition patterns in human airways. However, current lab-grade and portable instruments that assess airborne NPs only measure their size distribution; in addition, they are bulky and expensive, limiting their application to the analysis of individual NP exposure. To overcome these limitations, in this paper, we introduce and successfully demonstrate an NP analyzer realized in a mini-fluidic system whose main components were realized on two printed circuit boards (PCBs) that were subsequently adjoined. Our sensor could analyze the effective density and lognormal size distribution (number concentration, median diameter, and geometric standard deviation) of NPs in real time. Moreover, since an innovative NP analysis algorithm based on a parallel-type microfluidic inertial impaction technique is integrated in a miniature system, our sensor was portable (16.0 × 9.9 × 7.85 cm3, 980 g) and cost-efficient. In performance tests using synthesized NPs and in real-world environmental application tests, the performance of our sensor was comparable to that of conventional NP analysis systems. These results indicate that our mini-system is excellently suited to be used in hand-held sensors or distributed sensor networks for personal NP exposure monitoring, and toxicological studies.

Development of a method to determine workers' personal exposure levels to glyphosate.

ObjectivesWe aimed to develop a method to determine workers' personal exposure levels to N‐(phosphonomethyl)glycine (glyphosate) for their risk assessments.MethodsThe proposed method was assessed as follows: recovery, stability of samples on storage, method limit of quantification, and reproducibility. Glyphosate in air was sampled using an air‐sampling cassette containing a glass fiber filter. Ultrapure water was used to extract glyphosate from sampler filters. After derivation with 9‐fluorenylmethyloxycarbonyl chloride, samples were analyzed by high‐performance liquid chromatography using a fluorescence detector.ResultsSpiked samples indicated an overall recovery of 101%. After 7 days of storage at 4°C, recoveries were approximately 100%. The method limit of quantification was 0.060 μg/sample. Relative standard deviations representing overall reproducibility, defined as precision, were 1.4%–1.8%.ConclusionsThe method developed in this study allows 4‐h personal exposure monitoring of glyphosate at 0.250–500 μg/m3. Thus, this method can be used to estimate worker exposure to glyphosate.

Establishing A Sustainable Low-Cost Air Quality Monitoring Setup: A Survey of the State-of-the-Art.

Low-cost sensors (LCS) are becoming popular for air quality monitoring (AQM). They promise high spatial and temporal resolutions at low-cost. In addition, citizen science applications such as personal exposure monitoring can be implemented effortlessly. However, the reliability of the data is questionable due to various error sources involved in the LCS measurement. Furthermore, sensor performance drift over time is another issue. Hence, the adoption of LCS by regulatory agencies is still evolving. Several studies have been conducted to improve the performance of low-cost sensors. This article summarizes the existing studies on the state-of-the-art of LCS for AQM. We conceptualize a step by step procedure to establish a sustainable AQM setup with LCS that can produce reliable data. The selection of sensors, calibration and evaluation, hardware setup, evaluation metrics and inferences, and end user-specific applications are various stages in the LCS-based AQM setup we propose. We present a critical analysis at every step of the AQM setup to obtain reliable data from the low-cost measurement. Finally, we conclude this study with future scope to improve the availability of air quality data.

Development of the safety and health training materials using a PID personal exposure monitor in university workplaces

Development of the safety and health training materials using a PID personal exposure monitor in university workplaces

The exposome in practice: an exploratory panel study of biomarkers of air pollutant exposure in Chinese people aged 60-69 years (China BAPE Study).

The exposome overhauls conventional environmental health impact research paradigms and provides a novel methodological framework that comprehensively addresses the complex, highly dynamic interplays of exogenous exposures, endogenous exposures, and modifiable factors in humans. Holistic assessments of the adverse health effects and systematic elucidation of the mechanisms underlying environmental exposures are major scientific challenges with widespread societal implications. However, to date, few studies have comprehensively and simultaneously measured airborne pollutant exposures and explored the associated biomarkers in susceptible healthy elderly subjects, potentially resulting in the suboptimal assessment and management of health risks. To demonstrate the exposome paradigm, we describe the rationale and design of a comprehensive biomarker and biomonitoring panel study to systematically explore the association between individual airborne exposure and adverse health outcomes. We used a combination of personal monitoring for airborne pollutants, extensive human biomonitoring, advanced omics analysis, confounding information, and statistical methods. We established an exploratory panel study of Biomarkers of Air Pollutant Exposure in Chinese people aged 60-69years (China BAPE), which included 76 healthy residents from a representative community in Jinan City, Shandong Province. During the period between September 2018 and January 2019, we conducted prospective longitudinal monitoring with a 3-day assessment every month. This project: (1) leveraged advanced tools for personal airborne exposure monitoring (external exposures); (2) comprehensively characterized biological samples for exogenous and endogenous compounds (e.g., targeted and untargeted monitoring) and multi-omics scale measurements to explore potential biomarkers and putative toxicity pathways; and (3) systematically evaluated the relationships between personal exposure to air pollutants, and novel biomarkers of exposures and effects using exposome-wide association study approaches. These findings will contribute to our understanding of the mechanisms underlying the adverse health impacts of air pollution exposures and identify potential adverse clinical outcomes that can facilitate the development of effective prevention and targeted intervention techniques.

User-Centred Design of a Final Results Report for Participants in Multi-Sensor Personal Air Pollution Exposure Monitoring Campaigns.

Using low-cost portable air quality (AQ) monitoring devices is a growing trend in personal exposure studies, enabling a higher spatio-temporal resolution and identifying acute exposure to high concentrations. Comprehension of the results by participants is not guaranteed in exposure studies. However, information on personal exposure is multiplex, which calls for participant involvement in information design to maximise communication output and comprehension. This study describes and proposes a model of a user-centred design (UCD) approach for preparing a final report for participants involved in a multi-sensor personal exposure monitoring study performed in seven cities within the EU Horizon 2020 ICARUS project. Using a combination of human-centred design (HCD), human–information interaction (HII) and design thinking approaches, we iteratively included participants in the framing and design of the final report. User needs were mapped using a survey (n = 82), and feedback on the draft report was obtained from a focus group (n = 5). User requirements were assessed and validated using a post-campaign survey (n = 31). The UCD research was conducted amongst participants in Ljubljana, Slovenia, and the results report was distributed among the participating cities across Europe. The feedback made it clear that the final report was well-received and helped participants better understand the influence of individual behaviours on personal exposure to air pollution.

Combining Indoor Positioning Using Wi-Fi Round Trip Time with Dust Measurement in the Field of Occupational Health.

Monitoring of personal exposure to hazardous substances has garnered increasing attention over the past few years. However, no straightforward and exact indoor positioning technique has been available until the recent discovery of Wi-Fi round trip time (Wi-Fi RTT). In this study, we investigated the possibility of using a combination of Wi-Fi RTT for indoor positioning and a wearable particle monitor (WPM) to observe dust concentration during walking in a simulated factory. Ultrasonic humidifiers were used to spray sodium chloride solution inside the factory. The measurements were recorded three times on different routes (Experiments A, B, and C). The error percentages, i.e., measurements that were outside the expected measurement area, were 7% (49 s/700 s) in Experiment A, 2.3% (15 s/660 s) in Experiment B, and 7.8% (50 s/645 s) in Experiment C. The dust measurements were also recorded without any obstruction. A heat map was created based on the results from both measured values. Wi-Fi RTT proved useful for computing the indoor position with high accuracy, suggesting the applicability of the proposed methodology for occupational health monitoring.

Real-Time Low-Cost Personal Monitoring for Exposure to PM2.5 among Asthmatic Children: Opportunities and Challenges

This study aims to evaluate the accuracy and effectiveness of real-time personal monitoring of exposure to PM concentrations using low-cost sensors, in comparison to conventional data collection method based on fixed stations. PM2.5 data were measured every 5 min using a low-cost sensor attached to a bag carried by 47 asthmatic children living in the Seoul Metropolitan area between November 2019 and March 2020, along with the real-time GPS location, temperature, and humidity. The mobile sensor data were then matched with station-based hourly PM2.5 data using the time and location. Despite some uncertainty and inaccuracy of the sensor data, similar temporal patterns were found between the two sources of PM2.5 data on an aggregate level. However, average PM2.5 concentrations via personal monitoring tended to be lower than those from the fixed stations, particularly when the subjects were indoors, during nighttime, and located farther from the fixed station. On an individual level, a substantial discrepancy is observed between the two PM2.5 data sources while staying indoors. This study provides guidance to policymakers and researchers on improving the feasibility of personal monitoring via low-cost mobile sensors as an alternative or supplement to the conventional station-based monitoring.