Respiratory Effects of High Levels of Particulate Exposure in a Cohort of Traffic Police in Kathmandu, Nepal

Assessment of air quality in the Philadelphia, Pennsylvania subway

BACKGROUND

Subways are popular and efficient modes of transportation in cities. However, people are exposed to high levels of particulate matter (PM) in subways. Subway air quality in the United States has been investigated in a few cities, but data is lacking on simultaneous measurement of several pollutants, especially ultrafine particles (UFP) and black carbon (BC), in combination with different size fractions of PM.

OBJECTIVES

The goals of this study are to assess air quality in a belowground subway and compare it with outdoor ambient levels, to examine temporal variability of PM in the subway, and to analyze the correlation between PM and BC.

METHODS

Particulate matter of varying sizes (PM1, PM2.5, PM10), UFP, and BC were measured using DustTrak, nanoparticle detector, and micro aethalometer, respectively. Measurements were made at the belowground subway platform and the aboveground street level at 15th Street subway station in Philadelphia during summer 2022.

RESULTS

Belowground mean PM1, PM2.5, and PM10 were 112.2 ± 61.3 µg/m3, 120 ± 65.5 µg/m3, and 182.1 ± 132 µg/m3, respectively, which were 5.4, 5.7, and 7.6 times higher than the respective aboveground street levels. The UFP lung deposited surface area (LDSA) (59.4 ± 36.2 µm2/cm3) and BC (9.5 ± 5.4 μg/m3) belowground were 1.7 times and 10.7 times higher than the aboveground. The pollutant concentration varied from day-to-day on both the locations. A higher positive correlation was found between the belowground BC and PM2.5 (r = 0.51, p < 0.05) compared to the aboveground (r = 0.16, p < 0.05).

IMPACT

This study showed high levels of particulate matter exposure at a belowground subway station in Philadelphia. Particulate matter levels were about 5 to 8 times higher at belowground subway station than the corresponding aboveground street level. Higher levels were also observed for UFP lung deposited surface area (LDSA), while black carbon levels showed the highest concentration at the belowground level by a factor of ten compared to the aboveground level. The study shows the need for air quality management at belowground subways to reduce particulate matter exposure for the commuters.

Indoor and outdoor air quality in street corner kiosks in a large metropolitan area

Poor air quality in workplaces constitutes a great concern on human health as a good fraction of our time is spent at work. In Greece, very unique workplaces are the street corner kiosks, which are freestanding boxes placed on sidewalks next to city streets and vehicular traffic, where one can find many consumer goods. As such, its employees are exposed to both outdoor and indoor air pollutants. Very few studies have examined the occupational exposure of kiosk workers to air pollutants, and thus the magnitude of this unique indoor and outdoor exposure remains unknown. The objective of this study is to investigate and compare the levels of indoor and outdoor particulate matter (PM10 and PM2.5), ultrafine particles (UFPs) and black carbon (BC) in different kiosks located in Athens, Greece, in urban-traffic and urban-background environments. Continuous measurements of the above-mentioned pollutants were carried out on a 24-h basis over 7 consecutive days at three kiosks from September to October 2019. Indoor PM10 concentrations in the urban kiosk ranged from 19.0 to 44.0 μg/m3, PM2.5 values ranged from 14.0 to 33.0 μg/m3, whereas BC concentrations ranged from 1.2 to 7.0 μg/m3 and UFPs from almost 9.5 to 47.0 × 103 pt/cm3. Outdoor PM10 and PM2.5 measurements ranged from 29.0 to 59.0 μg/m3 and from 22.0 to 39.0 μg/m3, respectively. BC outdoor concentrations ranged from 1.1 to 2.2 μg/m3. The mean hazard quotient (HQ) for PM10 (4.9) and PM2.5 (4.7) among all participants was >1. The health risk of exposure to PM10 and PM2.5 was found to be at moderate hazard levels, although in some cases we observed HQ values higher than 10 due to high PM10 and PM2.5 concentrations in the kiosks. Overall our study indicates that people working at kiosks can be exposed to very high concentrations on particulate pollution depending on a number of factors including the traffic that strongly depends on location and the time of the day.

Selenium-Enriched Soybean Peptides as Novel Organic Selenium Compound Supplements: Inhibition of Occupational Air Pollution Exposure-Induced Apoptosis in Lung Epithelial Cells

The occupational groups exposed to air pollutants, particularly PM2.5, are closely linked to the initiation and advancement of respiratory disorders. The aim of this study is to investigate the potential protective properties of selenium-enriched soybean peptides (Se-SPeps), a novel Se supplement, in mitigating apoptosis triggered by PM2.5 in A549 lung epithelial cells. The results indicate a concentration-dependent reduction in the viability of A549 cells caused by PM2.5, while Se-SPeps at concentrations of 62.5-500 µg/mL showed no significant effect. Additionally, the Se-SPeps reduced the production of ROS, proinflammatory cytokines, and apoptosis in response to PM2.5 exposure. The Se-SPeps suppressed the PM2.5-induced upregulation of Bax/Bcl-2 and caspase-3, while also restoring reductions in p-Akt in A549 cells. The antiapoptotic effects of Se-SPeps have been found to be more effective compared to SPeps, SeMet, and Na2SeO3 when evaluated at an equivalent protein or Se concentration. Our study results furnish evidence that supports the role of Se-SPeps in reducing the harmful effects of PM2.5, particularly in relation to its effect on apoptosis, oxidative stress, and inflammation.

The health effects of wearing facemasks on cardiopulmonary system of healthy young adults: A double-blinded, randomized crossover trial

BACKGROUND

Facemask had increasingly been utilized as a personal protective measure to reduce exposure to ambient particulate matter (PM) during heavily-polluted days and routine life. However, evidence on the potential effects on cardiovascular system by wearing particulate-filtering facemask was limited.

METHODS

We conducted a double-blinded randomized crossover trial (RCT) to evaluate the effects of wearing N95 facemasks on the molecular responses of cardiopulmonary system among 52 healthy college students in Beijing, China. We measured cardiopulmonary health indicators and collected biological samples before and after (up to 5 h at multiple time points) a 2-h walk to examine the changes in lung function, biomarkers of respiratory and systemic oxidative stress/inflammation. We applied linear mixed-effect models to evaluate the effect of the facemask-intervention on the health of cardio-pulmonary system.

RESULTS

In the trial wearing real facemasks, FEV₁ increased by 2.05% (95% CI: 0.27%-3.87%), 2.80% (95% CI: 1.00%-4.63%), and 2.87% (95% CI: 1.07%-4.70%) at V1 (30-min), V2 (3-h), and V3 (5-h) after the 2-h walk outsides, respectively. Compared with participants wearing the sham mask, the percentage change of nitrate in EBC was lower among those wearing the real mask. After the 2-h exposure, urinary MDA levels increased compared to the baseline in both trials. Real trial was lower than sham trial for 6 cytokines (i.e., IL-6, IL-10, IL-13, IL-17A, IFN-γ and TNF-α) in serum at 5-h post-exposure. Wearing facemasks on polluted days produced better improvement, however, on cleaner days, the improvement was weaker.

CONCLUSIONS

Short-term use of N95 facemasks appeared to effectively reduce the levels of lung function declines, the respiratory oxidative stress, and the systemic inflammation/oxidative stress which may be induced by short-term exposure to PM. Wearing facemasks on polluted days (PM_2.5 > 75 μg/m³) presented larger beneficial effects on the cardiopulmonary health than in clean days (PM_2.5 < 75 μg/m³).

Short-term association of in-vehicle ultrafine particles and black carbon concentrations with respiratory health in Parisian taxi drivers

INTRODUCTION

Professional drivers are exposed inside their vehicles to high levels of air pollutants due to the considerable time they spend close to motor vehicle emissions. Little is known about ultrafine particles (UFP) or black carbon (BC) adverse respiratory health effects compared to the regulated pollutants.

OBJECTIVES

We aimed to study the short-term associations between UFP and BC concentrations inside vehicles and (1) the onset of mucosal irritation and (2) the acute changes in lung function of Parisian taxi drivers during a working day.

METHODS

An epidemiological study was carried out on 50 taxi drivers in Paris. UFP and BC were measured inside their vehicles with DiSCmini® and microAeth®, respectively. On the same day, the frequency and the severity of nose, eye, and throat irritations were self-reported by each participant and a spirometry test was performed before and after the work shift. Multivariate analysis was used to evaluate the associations between in-taxis UFP and BC concentrations and mucosal irritation and lung function, after adjustment for potential confounders.

RESULTS

In-taxis UFP concentrations ranged from 17.9 to 37.9 × 10³ particles/cm³ and BC concentrations from 2.2 to 3.9 μg/m3, during a mean of 9 ± 2 working hours. Significant dose-response relationships were observed between in-taxis UFP concentrations and both nasal irritation and lung function. The increase of in-taxis UFP (for an interquartile range of 20 × 10³ particles/cm³) was associated to an increase in nasal irritation (adjusted OR = 6.27 [95% CI: 1.02 to 38.62]) and to a reduction in forced expiratory flow at 25-75% by -7.44% [95% CI: -12.63 to -2.24], forced expiratory volume in one second by -4.46% [95% CI: -6.99 to -1.93] and forced vital capacity by -3.31% [95% CI: -5.82 to -0.80]. Such associations were not found with BC. Incident throat and eye irritations were not related to in-vehicle particles exposure; however, they were associated with outdoor air quality (estimated by the Atmo index) and in-vehicle humidity, respectively.

CONCLUSION

To our knowledge, our study is the first to show a significant association, within a short-period of time, between in and vehicle UFP exposure and acute respiratory effects in professional drivers.

Carcinogenic effects of indoor black carbon and particulate matters (PM2.5 and PM10) in rural households of India

Biomass is one of the prime domestic energy sources in the kitchens and about 60% of households are still using biomass and kerosene for cooking in India. These traditional cooking practices are incompetent as the use of biomass in traditional cookstove produces an enormous amount of carbonaceous aerosols that lead to indoor and outdoor air pollution. Emissions of various pollutants like black carbon (BC), PM₁₀ and PM_2.5 from burning of biomass cause serious health impacts like respiratory illness, lung cancer, watering of eyes, coughing, asthma and heart problems especially in women due to higher rate of inhalation of these fine particulate matters during the cooking period. Quantification of BC, PM_2.5 and PM₁₀ emissions from a different type of biomass in various types of kitchen arrangements and its associated impacts are poorly examined in India. Hence, daily concentrations of BC, PM_2.5 and PM₁₀ were monitored from different types of biomass user's households during January 2018 to December 2019 to assess indoor air quality by using aethalometer and nephelometer (pDR-1500) in three districts (Sitapur, Patna and Murshidabad) of Indo-Gangetic Plains (IGP) where approximately, 96% of rural families rely on biomass cooking. The highest mass concentrations were observed in biomass user's households and cow-dung cake users due to low calorific value. About 30.13% of PM₁₀ and 35.89% of PM_2.5 data exceeded the national ambient air quality standard on a daily basis in biomass user's households. A cancer risk assessment was also conducted in terms of mass concentration of these pollutants. The lifespan danger from exposure to BC was 4.33 × 10^-7 in indoor for non-ventilated kitchens, 2.63 × 10^-7 in indoor for ventilated kitchens, 3.98 × 10^-7 in outdoor for separated kitchen, 3.22 × 10^-7 for semi-open kitchen and 1.78 × 10^-7 for open kitchen. The vulnerability assessment for cancer mortality under exposure of pollution was estimated to be highest for the age group of more than 50 years whereas lowest for the age group of 0-4 years for all kinds of kitchens in the study area.

Personal strategies to minimise effects of air pollution on respiratory health: advice for providers, patients and the public

As global awareness of air pollution rises, so does the imperative to provide evidence-based recommendations for strategies to mitigate its impact. While public policy has a central role in reducing air pollution, exposure can also be reduced by personal choices. Qualified evidence supports limiting physical exertion outdoors on high air pollution days and near air pollution sources, reducing near-roadway exposure while commuting, utilising air quality alert systems to plan activities, and wearing facemasks in prescribed circumstances. Other strategies include avoiding cooking with solid fuels, ventilating and isolating cooking areas, and using portable air cleaners fitted with high-efficiency particulate air filters. We detail recommendations to assist providers and public health officials when advising patients and the public regarding personal-level strategies to mitigate risk imposed by air pollution, while recognising that well-designed prospective studies are urgently needed to better establish and validate interventions that benefit respiratory health in this context.

Mobile monitoring of air and noise pollution in Philadelphia neighborhoods during summer 2017

Mobile monitoring is a useful approach for measuring intra-urban variation of air pollution in urban environments. In this study, we used a mobile monitoring approach to study the spatial-temporal variability of air and noise pollution in urban neighborhoods of Philadelphia. During summer 2017, we used portable instruments to measure PM_2.5, black carbon (BC), and noise levels along 5 km paths in four residential neighborhoods (Tioga, Mill Creek, Chestnut Hill, and Northern Liberties) and one commercial district (Center City) in Philadelphia, Pennsylvania, USA. A total of 62 sets of measurements were made at three different times of day (during morning rush hour, mid-afternoon, and during afternoon rush hour) from June 5 to July 7, 2017. Spatially, there was a significant difference in PM_2.5 concentrations among the four residential neighborhoods. Overall, the Chestnut Hill neighborhood had the highest PM_2.5 concentrations (13.25 ± 6.89 μg/m³), followed by Tioga (9.58 ± 4.83 μg/m³), Northern Liberties (7.02 ± 4.17 μg/m³), and Mill Creek (3.9 ± 4.5 μg/m³). There was temporal variability of pollutants depending on the neighborhood; Northern Liberties demonstrated the highest temporal variability in these data. The highest PM_2.5 (18.86 ± 3.17 mg/m³) was measured in the Chestnut Hill neighborhood during mid-afternoon. Mean PM_2.5, BC, and noise levels based on mobile measurements at Philadelphia during summer 2017 were 8.41 ± 4.31 μg/m³, 0.99 ± 0.44 μg C/m³, and 62.01 ± 3.20 dBA, respectively. Environmental noise showed the highest temporal variation of the monitored components for 3 time periods. In general, tree cover showed a weak and inconclusive association with particulate pollution levels.

Levels of phthalate acid esters and sex hormones and their possible sources in traffic-patrol policemen in Chongqing

To investigate the correlation between the air phthalate acid ester (PAE) exposure and serum PAE concentration and the effects of PAE exposure on reproductive health among Chongqing traffic-patrol policemen. In 2013, 32 traffic-patrol policemen working in an area with poor air quality in Chongqing and 28 traffic-patrol policemen working in an area with good air quality were selected. Their blood levels of 14 PAEs and six reproductive hormones were determined. Air samples were collected from four traffic-patrol platforms. The concentrations of 14 PAEs in the air samples were evaluated. All 14 PAEs were detected in the blood samples. The concentrations of seven PAEs in the total suspended particulate, namely, dimethyl phthalate, diethyl phthalate, dibutyl phthalate, bis (2-ethox-yethyl) phthalate, dihexyl phthalate, benzyl butyl phthalate, and bis (2-n-butoxyethyl) phthalate, were positively and significantly associated with the blood levels of these PAEs in the participants. All the sex hormone levels measured here were significantly different between the participants from the two areas. The PAE concentrations in the blood samples were correlated with the reproductive hormone levels in the participants. Air PAE pollution may be a major source of PAE exposure in the traffic-patrol policemen of Chongqing.

Roadside Exposure and Inflammation Biomarkers among a Cohort of Traffic Police in Kathmandu, Nepal

Air pollution is a major environmental problem in the Kathmandu Valley. Specifically, roadside and traffic-related air pollution exposure levels were found at very high levels exceeding Nepal air quality standards for daily PM_2.5. In an exposure study involving traffic police officers, we collected 78 blood samples in a highly polluted spring season (16 February 2014–4 April 2014) and 63 blood samples in the less polluted summer season (20 July 2014–22 August 2014). Fourteen biomarkers, i.e., C-reactive protein (CRP), serum amyloid A (SAA), intracellular adhesion molecule (ICAM-1), vascular cell adhesion molecule (VCAM-1), interferon gamma (IFN-γ), interleukins (IL1-β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12, IL-13), and tumor necrosis factor (TNF-α) were analyzed in collected blood samples using proinflammatory panel 1 kits and vascular injury panel 2 kits. All the inflammatory biomarker levels were higher in the summer season than in the spring season, while particulate levels were higher in the spring season than in the summer season. We did not find significant association between 24-hour average PM_2.5 or black carbon (BC) exposure levels with most of analyzed biomarkers for the traffic volunteers working and residing near busy roads in Kathmandu, Nepal, during 2014. Inflammation and vascular injury marker concentrations were generally higher in females, suggesting the important role of gender in inflammation biomarkers. Because of the small sample size of female subjects, further investigation with a larger sample size is required to confirm the role of gender in inflammation biomarkers.

Uncorrected and corrected refractive error experiences of Nepalese adults: a qualitative study

PURPOSE

The aim of this study was to explore the impact of corrected and uncorrected refractive error (URE) on Nepalese people's quality of life (QoL), and to compare the QoL status between refractive error subgroups.

METHODS

Participants were recruited from Tilganga Institute of Ophthalmology and Dhulikhel Hospital, Nepal. Semi-structured in-depth interviews were conducted with 101 people with refractive error. Thematic analysis was used with matrices produced to compare the occurrence of themes and categories across participants. Themes were identified using an inductive approach.

RESULTS

Seven major themes emerged that determined refractive error-specific QoL: activity limitation, inconvenience, health concerns, psycho-social impact, economic impact, general and ocular comfort symptoms, and visual symptoms. Activity limitation, economic impact, and symptoms were the most important themes for the participants with URE, whereas inconvenience associated with wearing glasses was the most important issue in glasses wearers. Similarly, possibilities of having side effects or complications were the major concerns for participants wearing contact lens. In general, refractive surgery addressed socio-emotional impact of wearing glasses or contact lens. However, the surgery participants had concerns such as possibility of having to wear glasses again due to relapse of refractive error.

CONCLUSION

Impact of refractive error on people's QoL is multifaceted. Significance of the identified themes varies by refractive error subgroups. Refractive correction may not always address QoL impact of URE but often add unique QoL issues. This study findings also provide content for developing an item-bank for quantitatively measuring refractive error-specific QoL in developing country setting.

Short-term air pollution exposure decreases lung function: a repeated measures study in healthy adults

BACKGROUND

Daily changes in ambient concentrations of particulate matter, nitrogen oxides and ozone are associated with increased cardiopulmonary morbidity and mortality, with the lungs and their function being a vulnerable target.

METHODS

To evaluate the association between daily changes in air pollution and lung function in healthy adults we obtained annual lung function measurements from a routine worker health surveillance program not designed for research purposes. Forced Vital Capacity (FVC), Forced Expiratory Volume in the first second (FEV1), FEV1/FVC and Peak Expiratory flow (PEF) from a cohort of 2449 employees were associated with daily measurements of PM₁₀, NO₂ and ozone at a nearby monitoring station in the North of Belgium. Repeated measures were available for the period 2011-2015.

RESULTS

The mean (SD) PM₁₀ concentration on the day of the lung function test was 24.9 (15.5) μg/m³. A 10 μg PM₁₀/m³ increase on the day of the clinical examination was associated with a 18.9 ml lower FVC (95% CI: -27.5 to -10.3, p < 0.0001), 12.8 ml lower FEV1 (-19.1 to -6.5; p < 0.0001), and a 51.4 ml/s lower PEF (-75.0 to -27.0; p < 0.0001). The FEV1/FVC-ratio showed no associations. An increase of 10 μgNO₂/m³ was associated with a reduction in PEF (-66.1 ml/s (-106.6 to -25.6; p < 0.001)) on the day of the examination.

CONCLUSIONS

We found negative associations between daily variations in ambient air pollution and FVC, FEV1 and PEF in healthy adults.