Inhalation Rate Research Articles

Comparative Analysis of Spreader Grafts and Spreader Flaps on Intranasal Drug Delivery Efficiency to Posterolateral Nasal Wall

Background: This study compared the impact of spreader grafts (SG) and spreader flaps (SF) on the transport of intranasal drug delivery to target the posterolateral nasal wall. Method: SG and SF were each performed in sequence on two cadaveric specimens after soft tissue elevation technique. Computed tomography scans were acquired following each procedure to generate anatomic models for computational fluid dynamics simulation of intranasal sprays under the following conditions: inhalation rate (15 and 30 L/min), spray velocity (1, 5, and 10 m/s), spray released location (center, lateral, medial, top, and bottom), head position (upright, tilted-forward, tilted-backward, and supine), and particle diameter (1-100 µm). Percentage of particles deposited on the posterolateral nasal wall were calculated. Results: For Specimen 1, highest posterolateral wall depositions were Pre-Op: left = 74%, right = 74%; SF: left = 53%, right = 22%; SG: left = 60%, right = 61%. For Specimen 2, highest posterolateral wall depositions were Pre-Op: left = 25%, right = 83%; SF: left = 29%, right = 76%; SG: left = 14%, right = 72%. In general, posterolateral wall deposition was higher at 30 L/min inhalation rate and at 1 m/s spray velocity. Conclusions: Drug delivery targeting the posterolateral nasal wall appears to be dependent on many factors. However, midvault nasal reconstruction does not increase drug delivery to the posterolateral nasal wall.

Dry powder inhaler deposition in the larynx and the risk of steroid inhaler laryngitis: A computational fluid dynamics study

Dry Powder Inhalers (DPIs) are a mainstay in the treatment of obstructive respiratory diseases, including asthma and chronic obstructive pulmonary disease (COPD). Deposition of inhaled corticosteroids in the larynx elicits local side effects, potentially leading to steroid inhaler laryngitis. The objective of this study was to estimate the dose of DPIs that are deposited in the larynx relative to other regions of the respiratory tract using computational fluid dynamics (CFD). An anatomically accurate model of the airways (mouth to main bronchi) was constructed based on medical imaging of a healthy adult. Respiratory airflow and particle transport were simulated for constant inhalation rates of 30, 45, and 60 L/min. Two turbulence models were compared, namely the large eddy simulation (LES) and the k−ωSST models. DPIs were assumed to generate an aerosol cloud with a log-normal particle size distribution characterized by the mass median aerodynamic diameter (d50) and geometric standard deviation (σg). We compared two commercial DPIs, namely DPI 1 had a large particle size (d50 = 50 μm, σg=2.55) and DPI 2 had a small particle size (d50 = 2 μm, σg=1.99). The laryngeal dose was 1.6-to-3.8-fold higher than the bronchial dose for DPI 1, while the laryngeal and bronchial doses (units of mass per unit surface area) were similar for DPI 2 for both turbulence models and all inhalation rates. The choice of turbulence model had little impact on the total extrathoracic deposition, but a significant impact on regional doses, with the LES model predicting higher larynx-to-bronchi relative doses than the k−ω model. Our prediction that the larynx is a hotspot for DPI deposition is consistent with the observation of laryngeal side effects in DPI users. Importantly, our simulations suggest that DPIs with larger particles (d50 = 50 μm) may increase the risk of steroid inhaler laryngitis.

Evaluation of the preventive effect of sublingual immunotherapy for pediatric bronchial asthma

ObjectiveThis study aimed to determine the effectiveness of sublingual immunotherapy (SLIT) in preventing the exacerbation of asthma. MethodsThis retrospective study investigated the changes in the rate of continuous steroid inhalation introduced over three years due to SLIT in 328 patients aged 5–15 years who were diagnosed with allergic rhinitis between January 1, 2018, and December 31, 2019. These patients were not initially prescribed with continuous steroid inhalation. SLIT and symptomatic treatment groups were compared over 3 years using chi-square and Fisher's exact tests, controlling for age with multiple regression analysis. The SLIT subgroups and factors contributing to asthma exacerbation were examined as secondary endpoints. ResultsThe study comprised 151 patients in the SLIT group and 177 patients in the symptomatic treatment group, with higher average age and IgE levels in the SLIT group. High continuation rates for SLIT were observed over 3 years. Asthma exacerbation within 3 years was notably lower in the SLIT group, particularly in the cedar-only and combined SLIT groups. Multiple regression analysis confirmed the duration of SLIT as a significant factor in preventing asthma exacerbation. Additionally, Fisher's exact test supported these findings. ConclusionThis study demonstrated the effectiveness of SLIT in reducing the exacerbation of asthma in children with allergic rhinitis. SLIT was associated with lower rates of asthma exacerbation over a three-year period compared to symptomatic treatment.

Outcomes of burn patients presenting with hypotension within 48 hrs of admission to a level 1 Burn Centre

IntroductionBurns is one of the important presentations in trauma surgery in both first and third-world countries. Hypotension is often seen in the clinical presentation of a burn injury. Hypotension is the strongest independent predictor of an adverse outcome, according to a study done on emergency departments’ hospital outcomes; the lower the systolic, the worse the outcome. No direct study shows that presenting with or developing hypotension within 48hrs of admission and burn injury will have a worse outcome in our low-middle income setting. ObjectivesTo determine the outcomes of burn patients who developed hypotension within 48hrs of arrival at a Burn Centre in Johannesburg. In a singled time event. MethodsA retrospective descriptive study was conducted at a Level 1 Trauma Centre Burn unit in Johannesburg from 01 Jan 2019 to 31 Dec 2020. Patients who had a hypotensive episode at any point during the 48 h period were recruited. Hypotension was defined as a systolic blood pressure of less than 90mmhg. The patients were then divided into two groups: those who presented with or developed hypotension within 48hrs and those who did not. After that, the in-hospital mortality of both groups was to be determined. The study included all the patients who presented to the Burn Centre. Those younger than 18, or requiring readmission in the same study or delayed admissions of more than 24 h were excluded. Demographics, burn information, resuscitation data, outcomes and disposition status were evaluated. The STATA Statistics/Data Analysis version 16.0 was used to analyse the data. The level of significance was set at a p-value < 0.05. Ethical approval was obtained from the Human Research Ethics Committee (HREC) (medical) of the University of the Witwatersrand with the clearance number: M220132. ResultsOf the 132 patients seen, only 105 met the study inclusion criteria. Most patients were male: 91/105 (86.6 %). Flame burns accounted for the majority of the burns, 64/105 (60.95 %), followed by electrical burns, 26/105 (24.76 %). Hot water and chemical burns only accounted for 11/105 (10.48 %) and 4 (3.81 %) cases. Hypotension within 48hrs was noted in 37/105(35 %) of the cases. Hypotensive patients had an increased burn depth (p = 0.03), higher inhalation rate component (p = <0.001), greater lactate levels(p = 0.00001), higher baux score(p = 0.00001) and more likelihood of being placed on the ventilator (p = <0.00001) or dialysis (p = 0.008). Mortality was noted in 16 (43 %) of the patients who developed hypotension compared to 5 (7.4 %) patients of non-hypotensive patients (p < 0.001). The mortality of patients who presented with or developed hypotension was 9.59 times (95 % CI 3.1–29.4; p = 0.00001) higher than those who did not develop hypotension. Age and TBSA affected by burn, were found to have significant predictive value for mortality (p < 0.0001), respectively. Propensity matching was limited due to sample size. TBSA and the development of hypotension were matched, and the odds ratio of developing mortality was still increased. ConclusionHypotension was seen among burn injury patients admitted to a specialized intensive care unit. Hypotension was associated with higher TBSA % and increased age. In terms of characteristics, increased used of organ support was more likely with hypotensive patients with ventilation, inotropes, and dialysis. Length of stay was decreased in hypotensive patients. The odds of mortality were much higher in hypotensive patients, with age and TBSA being significant variables.

Effects of freebase/protonated nicotine concentration, liquid composition and electrical power on throat hit in direct-to-lung vaping: theory and clinical measurements

BackgroundFor decades, the tobacco industry has engineered the sensory characteristics of combustible tobacco products including the degree of harshness experienced at the back of the throat. Commonly referred to as...

Coupled Discrete Phase and Eulerian Wall Film Models for Drug Deposition Efficacy Analysis in Human Respiratory Airways.

The current study explores the effectiveness of drug particle deposition into human respiratory airways to cure various pulmonary-bound ailments. It has been assumed that drug solutions are inhaled in the form of tiny droplets or mist, which after striking create a thin layer along the inner surface of airways where the virus initially resides to infect the human body. A coupled Eulerian wall film (EWF) and discrete phase model (DPM) based simulation approach is used to capture these dynamics. Here, the Lagrangian DPM technique tracks the dynamics of tiny droplets, while the liquid layer formation after striking is captured using the Eulerian thin film approximations or the EWF model. Previous studies in this field primarily employed only the DPM method, which is inadequate to predict the poststriking dynamics of drug layer deposition and their spread to neutralize the respiratory virus. The drug delivery effectiveness is characterized by three different particle sizes, 1, 5, and 10 μm at the inhalation rates of 15, 30, and 60 L per minute (LPM). It has been found that the size of the drug particles significantly influences drug delivery effectiveness. The film thickness increases monotonically with particle sizes and inhalation rates. However, this increase in averaged film thickness is prominent in the range 5 to 10 μm (≈60%) compared to 1 to 5 μm (≈10%) droplet sizes at generation level 4 (G4). The other deposition parameters, e.g., deposition fraction, deposition density, and area coverage) roughly show similar behavior with the increase in droplet sizes. Therefore, it is recommended to vary the droplet sizes between 5 and 10 μm for better deposition effectiveness. The sizes of more than 10 μm mostly stuck into the oral cavity and cannot reach the targeted generations. In contrast, less than 5 μm may reach much deeper generations than the targeted one.

Trihalomethanes in chlorinated drinking water: Seasonal variations and health risk assessment in southern Iran

Assessing the adverse impacts of trihalomethanes, the most hazardous disinfection by-products, is crucial for community health protection. This study evaluated physicochemical parameters, trihalomethane levels, their prediction, and risk assessment using probability and Sobol analysis. Results indicated that electrical conductivity, total dissolved solids, nitrate, sulfate, calcium, lithium, total organic carbon, and ammonium exceeded permissible limits. Tribromomethane (0.14–3.21 μg/L in winter; 0.06–0.17 μg/L in summer), trichloromethane (1.90–3.53 μg/L in winter; 3.19–5.44 μg/L in summer), bromodichloromethane (0.62–4.24 μg/L in winter; 3.27–6.41 μg/L in summer), and dibromochloromethane (0.82–2.41 μg/L in winter; 0.69–3.03 μg/L in summer) remained within safe limits. Random Forest analysis identified total organic carbon as the most significant factor in trihalomethane production, with a positive correlation between trihalomethanes and bromide. Per the World Health Organization's risk assessment, trihalomethane concentrations posed no harm to residents (IWHO<1). However, the United States Environmental Protection Agency's assessment indicated an acceptable low cancer risk (100% cumulative cancer risk for all groups). Additionally, nitrate and fluoride levels surpassed the standard limit, with hazard index above 1 in both seasons for residents. Monte Carlo simulations showed that the 95th percentile of residents faced non-carcinogenic (nitrate and fluoride). However, 100% of children and 99.98% of adults were exposed to an acceptable low carcinogenic risk for THMs. Factors like inhalation rate, body weight, and trihalomethane levels significantly impacted health risk. These findings highlight the necessity for continuous monitoring and effective water treatment to safeguard public health, promote clean water, and advance sustainable development, advocating for sustainable water management to tackle health risks from environmental pollutants like disinfection by-products.

Feasibility Study on the Use of NO2 and PM2.5 Sensors for Exposure Assessment and Indoor Source Apportionment at Fixed Locations.

Recent advances in sensor technology for air pollution monitoring open new possibilities in the field of environmental epidemiology. The low spatial resolution of fixed outdoor measurement stations and modelling uncertainties currently limit the understanding of personal exposure. In this context, air quality sensor systems (AQSSs) offer significant potential to enhance personal exposure assessment. A pilot study was conducted to investigate the feasibility of the NO2 sensor model B43F and the particulate matter (PM) sensor model OPC-R1, both from Alphasense (UK), for use in epidemiological studies. Seven patients with chronic obstructive pulmonary disease (COPD) or asthma had built-for-purpose sensor systems placed inside and outside of their homes at fixed locations for one month. Participants documented their indoor activities, presence in the house, window status, and symptom severity and performed a peak expiratory flow test. The potential inhaled doses of PM2.5 and NO2 were calculated using different data sources such as outdoor data from air quality monitoring stations, indoor data from AQSSs, and generic inhalation rates (IR) or activity-specific IR. Moreover, the relation between indoor and outdoor air quality obtained with AQSSs, an indoor source apportionment study, and an evaluation of the suitability of the AQSS data for studying the relationship between air quality and health were investigated. The results highlight the value of the sensor data and the importance of monitoring indoor air quality and activity patterns to avoid exposure misclassification. The use of AQSSs at fixed locations shows promise for larger-scale and/or long-term epidemiological studies.

Distributions of polycyclic aromatic hydrocarbons in ambient air samples from Hanoi urban areas, Vietnam, and its implications for inhalation exposure.

Sixteen PAHs in ambient air samples collected from residential and roadside areas in the Hanoi metropolitan were investigated. Total PAH concentrations in the ambient air samples ranged from 45.0 to 451ng/m3. Among PAHs, phenanthrene was found at the most abundant and highest levels. The distributions of PAHs in the ambient air collected in the dry season were on average 26% higher than in the wet season. The PAH concentrations in the air samples collected from the traffic areas were significantly higher (about 2.7 times) than those in the residential areas, indicating that these chemicals originated from motor vehicles. According to vertical, the PAH concentrations found in the ambient air samples collected from the ground floor were significantly higher than on the upper level, however, there was not much difference when going higher (from 24m (8th floor) to 111m (37th floor)). The human exposure doses were estimated for two age groups (adults and children) based on the measured PAH concentrations, the inhalation rates, and body weights. The estimated exposure doses to PAHs through inhalation for adults/children were 1.13/2.86 (ng/kg-bw/d) (residential areas) and 3.24/8.18 (ng/kg-bw/d) (traffic areas), respectively. The average lifetime excess cancer risk (ECR) from inhalation exposure to PAHs was 3.0 × 10-4 at the traffic areas and 1.4 × 10-4 at the residential areas. These estimated exposure doses were above the acceptable level of the California Environmental Protection Agency (CalEPA) Office of Environmental Health Hazard Assessment (1*10-6).

Identifying high-risk volatile organic compounds in residences of Chinese megacities: A comprehensive health-risk assessment

Indoor volatile organic compounds (VOCs) pose considerable health hazards. However, research on hazardous VOCs in Chinese residences has been conducted on a limited spectrum. This study used Monte Carlo simulations with data from Beijing, Shanghai, and Shenzhen to assess VOC health risks in Chinese homes. We identified high-risk VOCs and analyzed the impact of geographic location, age group, activity duration, and inhalation rate on VOC exposure, including lifetime risks. Formaldehyde, acrolein, naphthalene, and benzene posed the highest risks. Notably, acrolein made the leading contribution to non-cancer risks across all megacities. Naphthalene had elevated cancer and non-cancer risks in Shenzhen. This study highlights the need to investigate acrolein and naphthalene, which are currently unregulated but pose substantial health risks. The cumulative cancer risk (TCR) decreases from adults to children, while the cumulative non-cancer risk (HI) is higher for children. In all cities, the average TCR for adults exceeds the tolerable threshold of 10−4, and the average HI values surpass the safety threshold of 1. Nearly 100 % of the population faces a lifetime cancer risk above 10−4, and over 71 % face a non-cancer risk exceeding 10 (tenfold the benchmark). This study underscores the critical need for developing control strategies tailored to VOCs.

Tracking of microplastics distribution patterns and their characterisation in deposited road dust from Dhaka city, Bangladesh

The widespread presence of microplastics (MPs) in road dust has considerable concern regarding their potential risks to ecosystems and human health. Despite the massive production of plastic, the erudition of MPs distribution patterns in various sizes of deposited road dust is still limited around the globe. Thus, the aim of this research is to provide an unambiguous picture of MPs distributional pattern, identification, classification, quantification, and features from road dust in various zones and types of roadways in Dhaka, Bangladesh. This study examined MPs in road dust samples with particle sizes ranging from 300 to 150 μm (Group-A), 149-75 μm (Group-B), and <75 μm (Group-C). This work extracted MPs from road dust using 30 % H2O2, 1.6 g/cm3 ZnCl2, and 0.45 μm filter paper. A fluorescent microscope (Motic B410E, Germany), Motic Pictures, and 3.0 ML software were utilized to identify MPs visually. Additionally, FTIR and SEM were utilized to determine the chemical composition of MPs. Group-A Road dust samples had a significantly higher concentration of MPs (38945 items/kg) compared to Group-B and <75 μm Group-C dust (16720 and 5945 items/kg, respectively). The distribution hierarchy for total MPs on average by location and type of road is as follows: paved road (355 items/5 g) > unpaved road (325 items/5 g) > soil samples (294 items/5 g), roadside dust samples (284 items/5 g), and mid-road (283 items/5 g). By taking into account all sizes of road dust samples, the MPs were classified as fiber (70.26 %), fragment (26.12 %), beads (0.66 %), films (1.32 %), and foams (1.58 %). It was found that adults inhaled MPs an average of 1612 items/day, while they ingested an average of 880 items/day. Children had an inhalation rate of 1232 items/day and an ingestion rate of 10267 items/day, which was 4–17 times greater than in other countries. This study identified 22 MPs polymer types, and SEM results show that MPs surfaces are being weathered into nanoplastics, creating a more hazardous environment.

Age-related features of the choice of inhalers in chilren and adolescents with bronchial asthma and other respiratory diseases

The inhalation way of drug delivery seems to be the most logical for respiratory diseases. However, the most important condition for the effectiveness of inhalation therapy in children and adolescents along with the correct choice of the active substance is the selection of the optimal device and adequate execution of the inspiratory maneuver. When prescribing therapy attention should be paid to the inhalation technique of a particular patient and also take into account the likelihood of side effects when using certain devices. The article provides data on factors affecting the pulmonary deposit of the drug, the internal resistance of various inhalers which have the greatest informativeness for choosing a device along with the assessment of the inspiratory flow rate developed by the patient. The most problematic aspects of drug delivery to the respiratory tract in children under 5 years of age and in patients with inadequate inhalation rate are analyzed. The principles of correct inhalation are discussed which are necessary to obtain an optimal respiratory fraction. It is known that the problem of synchronizing inhalation with the moment of receipt of the drug is the most important when using metered – dose aerosol inhalers. In children this problem can be solved by using a spacer or using nebulizers that convert the liquid form of the drug into an aerosol using compressor air. Individual selection of an inhaler depending on the abilities and preferences of the patient in some groups of patients can significantly increase the effectiveness of therapy without increasing the dose of medications. The article presents up-to-date data on digital inhaler systems and the possibilities of using electronic devices for monitoring and using the inhaler.

Occurrence and distribution of pesticides and transformation products in ambient air in two European agricultural areas

Pesticides present a significant risk for both humans and the environment. However, quantitative data for a broad range of airborne pesticides in agricultural areas are missing. During or after the application, pesticides can reach the atmosphere and partition between the particulate and gaseous phase. As part of the EU project SPRINT, weekly ambient air samples were collected from two agricultural areas in Portugal (vineyard) and the Netherlands (potatoes, onions, and sugarbeet) between April 2021 and June 2022 using high-volume air samplers. The samples were analysed for 329 pesticides, of which 99 were detected. The most frequently detected compounds included the fungicides folpet, fenpropidin and mandipropamid, the insecticide chlorpyrifos-methyl, the herbicide terbuthylazine, and the metabolite prothioconazole-desthio, which were found with detection frequencies between 40 and 57 %. Pesticide concentrations ranged between 0.003 ng/m3 and 10 ng/m3. Remarkably, 97 % of the samples contained at least one pesticide and in 95 % of the samples, pesticide mixtures were present. The calculated particle phase fractions correlated with the octanol-air partitioning coefficient for most of the investigated compounds. Furthermore, calculated daily inhalation rates for individual pesticides and pesticide mixtures were far below the Acceptable Daily Intake (ADI) with a margin of exposure (MOE) of >1000 for the highest calculated daily inhalation rate for a child. However, as this value only includes pesticide intake from food and drinking water and considering that 91 % of the detected pesticides are associated with potential adverse human health effects. These findings highlight the broad range of airborne pesticides in agricultural areas and the need for quantitative data to include the intake of mixtures of highly hazardous pesticides by inhalation in human risk assessment.

Physiologic oxygen responses to smoking opioids: an observational study using continuous pulse oximetry at overdose prevention services in British Columbia, Canada

BackgroundIn British Columbia, Canada, smoking is the most common modality of drug use among people who die of opioid toxicity. We aimed to assess oxygen saturation (SpO2) while people smoked opioids during a pilot study that introduced continuous pulse oximetry at overdose prevention services (OPS) sites.MethodsThis was an observational cohort study, using a participatory design. We implemented our monitoring protocol from March to August 2021 at four OPS. We included adults (≥ 18 years) presenting to smoke opioids. A sensor taped to participants’ fingers transmitted real-time SpO2 readings to a remote monitor viewed by OPS staff. Peer researchers collected baseline data and observed the timing of participants’ inhalations. We analyzed SpO2 on a per-event basis. In mixed-effects logistic regression models, drop in minimum SpO2 ≤ 90% in the current minute was our main outcome variable. Inhalation in that same minute was our main predictor. We also examined inhalation in the previous minute, cumulative inhalations, inhalation rate, demographics, co-morbidities, and substance use variables.ResultsWe recorded 599 smoking events; 72.8% (436/599) had analyzable SpO2 data. Participants’ mean age was 38.6 years (SD 11.3 years) and 73.1% were male. SpO2 was highly variable within and between individuals. Drop in SpO2 ≤ 90% was not significantly associated with inhalation in that same minute (OR: 1.2 [0.8–1.78], p = 0.261) or inhalation rate (OR 0.47 [0.20–1.10], p = 0.082). There was an association of SpO2 drop with six cumulative inhalations (OR 3.38 [1.04–11.03], p = 0.043); this was not maintained ≥ 7 inhalations. Demographics, co-morbidities, and drug use variables were non-contributory.ConclusionsContinuous pulse oximetry SpO2 monitoring is a safe adjunct to monitoring people who smoke opioids at OPS. Our data reflect challenges of real-world monitoring, indicating that greater supports are needed for frontline responders at OPS. Inconsistent association between inhalations and SpO2 suggests that complex factors (e.g., inhalation depth/duration, opioid tolerance, drug use setting) contribute to hypoxemia and overdose risk while people smoke opioids.

Ambient air concentrations of plant protection products: Data collection for the combined air concentration database and associated risk assessment

CropLife Europe collected literature values from monitoring studies measuring air concentrations of Plant Protection Products (PPPs) that may be inhaled by humans located in rural areas but not immediately adjacent to PPP applications. The resulting “Combined Air Concentration Database” (CACD) was used to determine whether air concentrations of PPPs reported by the French “Agency for Food, Environmental and Occupational Health & Safety” (ANSES) are consistent with those measured by others to increase confidence in values of exposure to humans. The results were put into risk assessment context. Results show that 25–90% of samples do not contain measurable PPP concentrations. Measured respirable fractions were below EU default air concentrations used for risk assessment for resident exposure by the European Food Safety Authority. All measured exposures in the CACD were also below established toxicological endpoints, even when considering the highest maximum average reported concentrations and very conservative inhalation rates. The highest recorded air concentration was for prosulfocarb (0.696 μg/m³ measured over 48 h) which is below the EFSA default limit of 1 μg/m³ for low volatility substances. In conclusion, based on the CACD, measured air concentrations of PPPs are significantly lower than EFSA default limits and relevant toxicological reference values.

Airborne microplastic contamination across diverse university indoor environments: A comprehensive ambient analysis

Microplastics (MPs) have become a growing concern in the context of environmental pollution, with an increasing focus on their presence in indoor environments, including university facilities. This study investigates the presence and characteristics of MPs in different university indoor environments. Initial examination of indoor ambient MPs involved physical characterization through optical microscopy, focusing on classifying MPs by shape and color. Various types of MPs, including fibers, fragments, pellets, foams, films, and lines, were identified, with the most common colors being black, red, blue, and brown. Fragments were the predominant type of MPs found, although accurately quantifying their numbers proved challenging due to the dense sample content. These MPs displayed rough and irregular margins suggestive of abrasion. Subsequent chemical and elemental characterization was conducted using micro-Raman and SEM-EDX, revealing the presence of 25 different types of MPs, including PA 66, PTFE, PP, HDPE, and PE. The study indicates that university inhabitants are exposed to airborne MPs (≥ 2.5–336.89 μm) at inhalation rates of 13.88–18.51 MPs/m3 and 180–240 MPs daily. These MPs exhibited significant variations in size, and their distribution varied among the different indoor environments studied. SEM-EDX analysis revealed common elements in the identified MPs, with C, O, F, Na, Cl, Al, Si, and others consistently detected. This research is the first to comprehensively analyze MPs in nine different indoor university environments using active sampling. Identifying and reducing MP contamination in these facilities might stimulate more awareness, promote extensive scientific investigation, and facilitate the development of informed policies.

Effects of Mucosal Decongestion on Nasal Aerodynamics: A Pilot Study.

Mucosal decongestion with nasal sprays is a common treatment for nasal airway obstruction. However, the impact of mucosal decongestion on nasal aerodynamics and the physiological mechanism of nasal airflow sensation are incompletely understood. The objective of this study is to compare nasal airflow patterns in nasal airway obstruction (NAO) patients with and without mucosal decongestion and nondecongested healthy subjects. Cross-sectional study of a convenience sample. Academic tertiary medical center. Forty-five subjects were studied (15 nondecongested healthy subjects, 15 nondecongested NAO patients, and 15 decongested NAO patients). Three-dimensional models of the nasal anatomy were created from computed tomography scans. Steady-state simulations of airflow and heat transfer were conducted at 15 L/min inhalation rate using computational fluid dynamics. In the narrow side of the nose, unilateral nasal resistance was similar in decongested NAO patients and nondecongested healthy subjects, but substantially higher in nondecongested NAO patients. The vertical airflow distribution within the nasal cavity (inferior vsmiddle vssuperior) was also similar in decongested NAO patients and nondecongested healthy subjects, but nondecongested NAO patients had substantially less middle airflow. Mucosal cooling, quantified by the surface area where heat flux exceeds 50 W/m2, was significantly higher in decongested NAO patients than in nondecongested NAO patients. This pilot study suggests that mucosal decongestion improves objective measures of nasal airflow, which is consistent with improved subjective sensation of nasal patency after decongestion.

Occupational health risk assessment of PC production-caused pollution based on damage assessment and cyclic mitigation model

PurposeThe occupational health risk associated with the production of prefabricated concrete components is often overlooked. This paper will use a damage assessment and cyclic mitigation (DACM) model to provide individualized exposure risk assessment and corresponding mitigation management measures for workers who are being exposed.Design/methodology/approachThe DACM model is proposed based on the concept of life cycle assessment (LCA). The model uses Monte-Carlo simulation for uncertainty risk assessment, followed by quantitative damage assessment using disability-adjusted life year (DALY). Lastly, sensitivity analysis is used to identify the parameters with the greatest impact on health risks.FindingsThe results show that the dust concentration is centered around the mean, and the fitting results are close to normal distribution, so the mean value can be used to carry out the calculation of risk. However, calculations using the DACM model revealed that there are still some work areas at risk. DALY damage is most severe in concrete production area. Meanwhile, the inhalation rate (IR), exposure duration (ED), exposure frequency (EF) and average exposure time (AT) showed greater impacts based on the sensitivity analysis.Originality/valueBased on the comparison, the DACM model can determine that the potential occupational health risk of prefabricated concrete component (PC) factory and the risk is less than that of on-site construction. It synthesizes field research and simulation to form the entire assessment process into a case-base system with the depth of the cycle, which allows the model to be continuously adjusted to reduce the occupational health damage caused by production pollution exposure.

Impact of altitude on the dosage of indoor particulates entering an individual’s small airways

The complexity of indoor particulate exposure intensifies at higher altitudes owing to the increased lung capacity that residents develop to meet the higher oxygen demands. Altitude variations impact atmospheric pressure and alter particulate dynamics in ambient air and the human respiratory tract, complicating particulate inhalation. This study assessed the fraction of PM2.5 and PM10 entering small airways. This assessment covered an altitude range from 400 m above sea level to 3650 m, and an in vitro respiratory tract model was used. The experimental results confirmed that with increasing altitude, the penetration fractions of PM2.5 and PM10 significantly increased from 0.133 ± 0.031 and 0.141 ± 0.045 to 0.404 ± 0.159 and 0.353 ± 0.132, respectively. Additionally, the computational fluid dynamics simulation results revealed that among particles with sizes of 0.1 to 10 µm, the 7.5-μm particles exhibited the most substantial reduction in deposition in the upper airway, displaying a decrease of 6.27%. Our findings underscore the health risks faced by low-altitude residents during acclimatization to higher altitudes, as they experience heightened exposure to particulate matter sources.

Environmental Health Risk Analysis of Sulfur Dioxide (SO2) Inhalation Exposure in Ambient Air Among the Tirtonirmolo Community, Bantul.

Introduction: Sulfur dioxide (SO2) is one of the gases that can pollute the ambient air and cause respiratory irritation. This study aims to determine the characterization of health risk and risk management of sulfur dioxide (SO2) exposure to prevent health impact in the Tirtonirmolo community, Bantul. Methods: This study was a quantitative descriptive research with an Environmental Health Risk Analysis (EHRA) approach. The study subjects were the Tirtonirmolo community in Bantul, with a sample of 110 respondents. The sampling method uses purposive sampling. Results and Discussion: Most respondents are female (74%) with ages over 54 years (52%), and the majority work as housewives (44%). The description of EHRA variables consists of an inhalation rate of 0.83 m3/hour, exposure time of 22 hours/day, exposure frequency of 354 days/year, and exposure duration for real-time projections of 35 years and 30 years for lifetime projections. The SO2 measurement results did not exceed the national quality standard, with the highest concentration being on Madukismo Road, with a concentration of 11.72 μg/m3. The dose-response analysis uses data from the US-EPA, which is 0.026 mg/kg/day. The real-time average intake value is 0.0039 mg/kg/day, and the 30-year lifetime average intake value is 0.0033 mg/kg/day. Conclusion: All respondents from this study had an RQ value&lt;1, both in the RQ for real-time and lifetime. Risk management needs to reduce health risk by using masks when doing outdoor activities and installing Flue Gas Desulfurization (FGD) in factories that emit SO2 emissions.