Electronic Cigarette Use during Pregnancy: Is It Harmful?

Although combustible cigarette smoking rates have declined in recent years, alternative tobacco product use, particularly electronic cigarette use ("vaping"), has increased among young adults. Recent studies indicate that vaping during pregnancy is on the rise, possibly due to the perception that it is a safer alternative to combustible cigarette smoking. However, e-cigarette aerosols may contain several newer, potentially toxic compounds, including some known developmental toxicants that may adversely impact both the mother and the fetus. However, there is paucity of studies that have examined the effects of vaping during pregnancy. While the adverse perinatal outcomes of cigarette smoking during pregnancy are well established, the specific risks associated with inhaling vaping aerosols during pregnancy requires more research. In this article, we discuss the existing evidence and knowledge gaps on the risks of vaping during pregnancy. Studies that investigate vaping-associated systemic exposure and its effects (i.e., biomarker analyses) and maternal and neonatal clinical health outcomes are needed to reach more robust conclusions. We particularly emphasize the need to go beyond comparative studies with cigarettes, and advocate for research that objectively evaluates the safety of e-cigarettes and other alternative tobacco products.

Sex Differences in Electronic Cigarette Device Use Among College Students.

Electronic cigarette use (vaping) has reached epidemic levels in the United States among teenagers and young adults. However, there is a paucity of studies that have examined the relationships between e-cigarette device types and user characteristics. Therefore, the main objective of this study was to characterize e-cigarette device use among a college population with a focus on sex differences in preferred vaping device. We employed a Qualtrics-based smartphone/online survey to gather responses on e-cigarette use; including device type, demographics and other related information during the period October 1, 2020 to January 30, 2022 in the Birmingham, AL metropolitan area. Participants were recruited via flyers with a QR code to the survey. The differences in e-cigarette device type used by the characteristics of the university e-cigarette users were assessed using either a Chi-square analysis or Fisher's Test. The magnitude of any association between the characteristics of the participants and vaping device used was analyzed via logistic regression. Out of 394 students who participated in the survey, 61 reported current exclusive e-cigarette use (15.5%) among our 18-24-year-old college student sample. Among vapers; more females reported use of Disposable e-cigarettes or Juul (pod-type) as their primary vaping device compared to males, who preferred Tanks and Mods + other rechargeable e-cigarettes (p < 0.05). Males also vaped more days per week compared to females. Vaping among young college students remains at concerning levels. The primary vaping device used significantly varies by the users' sex, making it an important factor to consider in future studies.

Effects of electronic cigarettes and hookah (waterpipe) use on home air quality.

INTRODUCTION: A major site of secondhand smoke exposure for children and adults is the home. Few studies have evaluated the impact of e-cigarette or hookah use on home air quality, despite evidence finding toxic chemicals in secondhand e-cigarette aerosols and hookah smoke. We assessed the effect of e-cigarette and hookah use on home air quality and compared it with air quality in homes where cigarettes were smoked and where no smoking or e-cigarette use occurred. METHODS: Non-smoking homes and homes where e-cigarettes, hookah or cigarettes were used were recruited in the New York City area (n=57) from 2015 to 2019. Particulate matter with diameter less than 2.5 µm (PM2.5), black carbon and carbon monoxide (CO) were measured during a smoking or vaping session, both in a 'primary' smoking room and in an adjacent 'secondary' room where no smoking or vaping occurred. Log transformed data were compared with postanalysis of variance Tukey simultaneous tests. RESULTS: Use of hookah significantly increased PM2.5 levels compared with non-smoking homes, in both the primary and secondary rooms, while use of e-cigarettes increased PM2.5 levels only in primary rooms. Additionally, in-home use of hookah resulted in greater CO concentrations than the use of cigarettes in primary rooms. CONCLUSIONS: Use of e-cigarettes or hookah increases air pollution in homes. For hookah, increases in PM2.5 penetrated even into rooms adjacent to where smoking occurs. Extending smoke-free rules inside homes to include e-cigarette and hookah products is needed to protect household members and visitors from passive exposure to harmful aerosols and gases.

Feasibility of low-cost particle sensor types in long-term indoor air pollution health studies after repeated calibration, 2019-2021.

Previous studies have explored using calibrated low-cost particulate matter (PM) sensors, but important research gaps remain regarding long-term performance and reliability. Evaluate longitudinal performance of low-cost particle sensors by measuring sensor performance changes over 2 years of use. 51 low-cost particle sensors (Airbeam 1 N = 29; Airbeam 2 N = 22) were calibrated four times over a 2-year timeframe between 2019 and 2021. Cigarette smoke-specific calibration curves for Airbeam 1 and 2 PM sensors were created by directly comparing simultaneous 1-min readings of a Thermo Scientific Personal DataRAM PDR-1500 unit with a 2.5 µm inlet. Inter-sensor variability in calibration coefficient was high, particularly in Airbeam 1 sensors at study initiation. Calibration coefficients for both sensor types trended downwards over time to < 1 at final calibration timepoint [Airbeam 1 Mean (SD) = 0.87 (0.20); Airbeam 2 Mean (SD) = 0.96 (0.27)]. We lost more Airbeam 1 sensors (N = 27 out of 56, failure rate 48.2%) than Airbeam 2 (N = 2 out of 24, failure rate 8.3%) due to electronics, battery, or data output issues. Evidence suggests degradation over time might depend more on particle sensor type, rather than individual usage. Repeated calibrations of low-cost particle sensors may increase confidence in reported PM levels in longitudinal indoor air pollution studies.

The Impact of COVID-19 Related Changes on Air Quality in Birmingham, Alabama, United States.

Air pollution is responsible for a wide range of health effects in exposed populations. Variations in local air pollution can affect local population health outcomes. The strict regulations imposed during the peak of the COVID-19 pandemic ('lockdowns') resulted in a unique situation where human mobility was limited significantly, resulting in improved air quality in several major cities. The main goal of this study was to investigate if lockdowns during the COVID-19 pandemic significantly impacted air quality in Birmingham, Alabama-a city with a history of high air pollution levels-with a focus on PM2.5 (Particulate Matter with an aerodynamic diameter ≤2.5 µm) and NO2 (Nitrogen dioxide). Daily air pollutant and traffic data were obtained for the Birmingham Metropolitan Area for the period January to October 2020, and previous years. Mean PM2.5 and NO2 concentrations and traffic volumes during the official city/state lockdown period (24 March to 30 April 2020) were compared to pre- and post-lockdown means. The mean PM2.5 and NO2 concentrations during the lockdown did not significantly differ from that of the pre- or post-lockdown periods. However, NO2 significantly decreased even after the lockdown order was removed, with the mean decreasing significantly compared to pre-lockdown and lockdown periods. Both PM2.5 and NO2 annual means in 2020 were significantly lower than the annual means in 2019, indicating the occurrence of significant changes over the longer term that were not limited by defined lockdown periods. Traffic significantly increased after the lockdown order was removed but did not correlate with the two pollutants studied. Therefore, we conclude that the Stay at Home/lockdown regulations and other COVID-19 restrictions had an impact on the air quality of Birmingham Alabama; although these lockdown impacts varied for each pollutant and were not limited only by the official lockdown dates/periods.

Travelling to polluted cities: a systematic review on the harm of air pollution on international travellers' health.

RATIONALE FOR REVIEW: In 2019, approximately, 1.4 billion people travelled internationally. Many individuals travel to megacities where air pollution concentrations can vary significantly. Short-term exposure to air pollutants can cause morbidity and mortality related to cardiovascular and respiratory disease, with the literature clearly reporting a strong association between short-term exposure to particulate matter ≤2.5 µm and ozone with adverse health outcomes in resident populations. However, limited research has been conducted on the health impacts of short-term exposure to air pollution in individuals who travel internationally. The objective of this systematic review was to review the evidence for the respiratory and cardiovascular health impacts from exposure to air pollution during international travel to polluted cities in adults aged ≥18 years old. KEY FINDINGS: We searched PubMed, Scopus and EMBASE for studies related to air pollution and the health impacts on international travellers. Of the initially identified 115 articles that fit the search criteria, 6 articles were selected for the final review. All six studies found indications of adverse health impacts of air pollution exposure on international travellers, with most of the changes being reversible upon return to their home country/city. However, none of these studies contained large populations nor investigated vulnerable populations, such as children, elderly or those with pre-existing conditions. CONCLUSIONS: More research is warranted to clearly understand the impacts of air pollution related changes on travellers' health, especially on vulnerable groups who may be at higher risk of adverse impacts during travel to polluted cities.

PM2.5 Concentration and Composition in Subway Systems in the Northeastern United States.

OBJECTIVES: The goals of this study were to assess the air quality in subway systems in the northeastern United States and estimate the health risks for transit workers and commuters. METHODS: We report real-time and gravimetric PM2.5 concentrations and particle composition from area samples collected in the subways of Philadelphia, Pennsylvania; Boston, Massachusetts; New York City, New York/New Jersey (NYC/NJ); and Washington, District of Columbia. A total of 71 stations across 12 transit lines were monitored during morning and evening rush hours. RESULTS: We observed variable and high PM2.5 concentrations for on-train and on-platform measurements during morning (from 0600 hours to 1000 hours) and evening (from 1500 hours to 1900 hours) rush hour across cities. Mean real-time PM2.5 concentrations in underground stations were 779±249, 548±207, 341±147, 327±136, and 112±46.7 µg/m3 for the PATH-NYC/NJ; MTA-NYC; Washington, DC; Boston; and Philadelphia transit systems, respectively. In contrast, the mean real-time ambient PM2.5 concentration taken above ground outside the subway stations of PATH-NYC/NJ; MTA-NYC; Washington, DC; Boston; and Philadelphia were 20.8±9.3, 24.1±9.3, 12.01±7.8, 10.0±2.7, and 12.6±12.6 µg/m3, respectively. Stations serviced by the PATH-NYC/NJ system had the highest mean gravimetric PM2.5 concentration, 1,020 µg/m3, ever reported for a subway system, including two 1-h gravimetric PM2.5 values of approximately 1,700 µg/m3 during rush hour at one PATH-NYC/NJ subway station. Iron and total carbon accounted for approximately 80% of the PM2.5 mass in a targeted subset of systems and stations. DISCUSSION: Our results document that there is an elevation in the PM2.5 concentrations across subway systems in the major urban centers of Northeastern United States during rush hours. Concentrations in some subway stations suggest that transit workers and commuters may be at increased risk according to U.S. federal environmental and occupational guidelines, depending on duration of exposure. This concern is highest for the PM2.5 concentrations encountered in the PATH-NYC/NJ transit system. Further research is urgently needed to identify the sources of PM2.5 and factors that contribute to high levels in individual stations and lines and to assess their potential health impacts on workers and/or commuters. https://doi.org/10.1289/EHP7202.

Mapping urban air quality using mobile sampling with low-cost sensors and machine learning in Seoul, South Korea.

Recent studies have demonstrated that mobile sampling can improve the spatial granularity of land use regression (LUR) models. Mobile sampling campaigns deploying low-cost (<$300) air quality sensors could potentially offer an inexpensive and practical approach to measure and model air pollution concentration levels. In this study, we developed LUR models for street-level fine particulate matter (PM2.5) concentration levels in Seoul, South Korea. 169 h of data were collected from an approximately three week long campaign across five routes by ten volunteers sharing seven AirBeams, a low-cost ($250 per unit), smartphone-based particle counter, while geospatial data were extracted from OpenStreetMap, an open-source and crowd-generated geographical dataset. We applied and compared three statistical approaches in constructing the LUR models - linear regression (LR), random forest (RF), and stacked ensemble (SE) combining multiple machine learning algorithms - which resulted in cross-validation R2 values of 0.63, 0.73, and 0.80, respectively, and identification of several pollution 'hotspots.' The high R2 values suggest that study designs employing mobile sampling in conjunction with multiple low-cost air quality monitors could be applied to characterize urban street-level air quality with high spatial resolution, and that machine learning models could further improve model performance. Given this study design's cost-effectiveness and ease of implementation, similar approaches may be especially suitable for citizen science and community-based endeavors, or in regions bereft of air quality data and preexisting air monitoring networks, such as developing countries.

A protocol for measuring the impact of a smoke-free housing policy on indoor tobacco smoke exposure.

BACKGROUND: Tobacco remains a leading cause of preventable death in the U.S., responsible for more than 440,000 deaths each year. Approximately 10% of these deaths are attributable to exposure of non-smokers to secondhand smoke (SHS). Residents living in public multi-unit housing (MUH) are at excess risk for SHS exposure compared to the general population. On November 30, 2016, the U.S. Department of Housing and Urban Development (HUD) passed a rule requiring all public housing agencies to implement smoke-free housing (SFH) policies in their housing developments by July 30, 2018. METHODS: As part of a larger natural experiment study, we designed a protocol to evaluate indoor SHS levels before and after policy implementation through collection of repeat indoor air samples in non-smoking apartments and common areas of select high-rise NYCHA buildings subject to the HUD SFH rule, and also from socio-demographically matched private-sector high-rise control buildings not subject to the rule. A baseline telephone survey was conducted in all selected buildings to facilitate rapid recruitment into the longitudinal study and assess smoking prevalence, behaviors, and attitudes regarding the SFH policy prior to implementation. Data collection began in early 2018 and will continue through 2021. DISCUSSION: The baseline survey was completed by 559 NYCHA residents and 471 comparison building residents (response rates, 35, and 32%, respectively). Smoking prevalence was comparable between study arms (15.7% among NYCHA residents and 15.2% among comparison residents). The majority of residents reported supporting a building-wide smoke-free policy (63.0 and 59.9%, respectively). We enrolled 157 NYCHA and 118 comparison non-smoking households into the longitudinal air monitoring study and performed air monitoring in common areas. Follow up surveys and air monitoring in participant households occur every 6 months for 2.5 years. Capitalizing on the opportunity of this federal policy rollout, the large and diverse public housing population in NYC, and robust municipal data sources, this study offers a unique opportunity to evaluate the policy's direct impacts on SHS exposure. Methods in this protocol can inform similar SFH policy evaluations elsewhere.

Exposure to air pollution is associated with adverse cardiopulmonary health effects in international travellers.

BACKGROUND: With the number of annual global travellers reaching 1.2 billion, many individuals encounter greater levels of air pollution when they travel abroad to megacities around the world. This study's objective was to determine if visits to cities abroad with greater levels of air pollution adversely impact cardiopulmonary health. METHODS: A total of 34 non-smoking healthy adult participants who travelled abroad to selected cities from the New York City (NYC) metropolitan area were pre-trained to measure lung function, blood pressure and heart rate (HR)/HR variability (HRV) and record symptoms before, during and after travelling abroad. Outdoor particulate matter (PM)2.5 concentrations were obtained from central monitors in each city. Associations between PM exposure concentrations and cardiopulmonary health endpoints were analysed using a mixed effects statistical design. RESULTS: East and South Asian cities had significantly higher PM2.5 concentrations compared with pre-travel NYC PM2.5 levels, with maximum concentrations reaching 503 µg/m3. PM exposure-related associations for lung function were statistically significant and strongest between evening Forced Expiratory Volume in the first second (FEV1) and same-day morning PM2.5 concentrations; a 10-µg/m3 increase in outdoor PM2.5 was associated with a mean decrease of 7 mL. Travel to a highly polluted city (PM2.5 > 100 µg/m3) was associated with a 209-ml reduction in evening FEV1 compared with a low polluted city (PM2.5 < 35 µg/m3). In general, participants who travelled to East and South Asian cities experienced increased respiratory symptoms/scores and changes in HR and HRV. CONCLUSIONS: Exposure to increased levels of PM2.5 in cities abroad caused small but statistically significant acute changes in cardiopulmonary function and respiratory symptoms in healthy young adults. These data suggest that travel-related exposure to increased PM2.5 adversely impacts cardiopulmonary health, which may be particularly important for travellers with pre-existing respiratory or cardiac disease.

Does air pollution contribute to travelers' illness and deaths?-evidence from a case report and need for further studies.

Annual increases in global travel have resulted in more individuals being exposed to varying environmental conditions abroad and, thereby, subject to air pollution related health risks. Individuals who travel abroad may be exposed to varying levels of air pollution within a matter of hours. We wish to consider whether exposure to air pollution could be a significant contributor to the risk of illness and death in travelers, particularly those who travel to highly polluted cities. We report the findings of a study in which the peak expiratory flow (PEF) of a traveler decreased in Shanghai relative to baseline in New York City; the decline in PEF correlated to concentration of particulate matter (PM2.5). We discuss the health implication of these results on global travel.

Effects of hookah smoking on indoor air quality in homes.

INTRODUCTION: Hookahs (water pipes) are rapidly increasing in popularity worldwide. Evidence suggests that although perceived as safer than cigarette smoke, hookah smoke may be as, or even more, dangerous as cigarette smoke. METHODS: Air samples from 33 homes-11 where only hookah-smoking occurred, 12 with only cigarettes and 10 with no smoking-were collected to analyse concentrations of particulate matter (PM2.5), black carbon, elemental and organic carbon and carbon monoxide (CO). Air quality was assessed in rooms where smoking occurred and in an adjacent room. RESULTS: Hookah and cigarette smoking impaired home air quality. The rooms in which hookahs were smoked showed the highest concentrations for all pollutants. CO was significantly greater in the rooms where hookahs were smoked than in the cigarette-smoking rooms and the non-smoking households (p<0.05). In addition, CO levels in the rooms adjacent to where hookah was smoked were 2.5-fold to 4-fold greater than those in the smoking and non-smoking rooms of the cigarette homes (p<0.05). PM2.5 levels were also elevated in hookah homes compared to cigarette and non-smoking homes, although not significantly different. CONCLUSIONS: This study, the first of its kind, demonstrates potentially hazardous levels of home air pollution in rooms where hookahs are being smoked as well as in adjacent rooms. These levels were greater than those in cigarette smoking homes, raising concerns about potential negative health effects on all individuals living in homes where hookahs are smoked.

Black carbon and particulate matter (PM2.5) concentrations in New York City's subway stations.

The New York City (NYC) subway is the main mode of transport for over 5 million passengers on an average weekday. Therefore, airborne pollutants in the subway stations could have a significant impact on commuters and subway workers. This study looked at black carbon (BC) and particulate matter (PM2.5) concentrations in selected subway stations in Manhattan. BC and PM2.5 levels were measured in real time using a Micro-Aethalometer and a PDR-1500 DataRAM, respectively. Simultaneous samples were also collected on quartz filters for organic and elemental carbon (OC/EC) analysis and on Teflon filters for gravimetric and trace element analysis. In the underground subway stations, mean real time BC concentrations ranged from 5 to 23 µg/m(3), with 1 min average peaks >100 µg/m(3), while real time PM2.5 levels ranged from 35 to 200 µg/m(3). Mean EC levels ranged from 9 to 12.5 µg/m(3). At street level on the same days, the mean BC and PM2.5 concentrations were below 3 and 10 µg/m(3), respectively. This study shows that both BC soot and PM levels in NYC's subways are considerably higher than ambient urban street levels and that further monitoring and investigation of BC and PM subway exposures are warranted.