Indoor Pollution Research Articles

Indoor air pollution: an Italian Knowledge, Attitude and Practice (KAP) study among the general population.

Indoor air pollution negatively affects population health and the national health services in terms of socio-economic costs. The presence of indoor pollutants depends a lot on lifestyles. The aim of this work is to evaluate knowledge, daily habits and the preventive behaviors in order to contrast the effects on health caused by indoor pollutants. The study was conducted through the administration of questionnaires to the population resident in the metropolitan city of Messina (Italy), asking about sociodemographic characteristics, knowledge, daily habits and preventive behaviors. The questionnaire was filled by 894 subjects (46.8% M; 53.2% F). Regarding knowledge, 66.8% had heard of indoor air pollution and 94.9% knew what the most common indoor pollutants are; regarding daily habits they often aired out the house (91.9% in the morning and 71.4% after cleaning), 24.8% were smokers and 36.7 of them smoked indoors; regarding preventive behaviors, 41.6% chose the cleaning products based on habit and only 32.9% bought plants able to purify environments. Although the analyzed population had adequate knowledge of indoor air pollution, this did not strongly impact on the adoption of healthy lifestyles. Therefore, it becomes necessary to intervene on a social level with environmental education activities, starting from school age.

Wildfires exacerbate inequalities in indoor pollution exposure

Wildfires lead to dramatic increases in fine particulate matter pollution concentrations. Based on the premise that higher-income households purchase more defensive investments to reduce the degree to which outdoor pollution infiltrates indoors, in this study, we investigate how income contributes to outdoor–indoor pollution infiltration rates during wildfire events. Using crowd-sourced data from the PurpleAir Real-Time Air Quality Monitoring Network and econometric models that explore variations in monitor readings over time, we find increases in outdoor pollution lead to significant increases in indoor pollution, but disproportionately so in lower-income areas. The results highlight a new inequality in pollution exposure: not only are outdoor pollution levels higher for lower-income individuals, but indoor pollution levels are higher even for similar outdoor pollution levels.

The application analysis of the eco-interior concept to My Dormy Hostel UMM as an effort to achieve environmental sustainability

Public awareness about environmental sustainability is increasing. Various approaches are being taken to address environmental issues, including in the field of interior design. One of the approaches that highlight environmental awareness and sustainability is known as eco-interior. My Dormy Hostel UMM is a pioneering hostel in Malang that utilizes repurposed containers as its primary building material. This study aims to observe the application of the eco-interior concept at My Dormy Hostel UMM, with diagnostic evaluation analysis based on the concept of eco-interior. The eco-interior concept is divided into four levels of classification: ideal situation, substantial and mild effort, and general application. The finding shows that falls under the third level of the eco-interior concept, “substantial effort”. The application of the concept is commendable but not yet considered ideal or optimal. Specifically, the ventilation system meets the standards for an ideal situation, while the space organization, material selection, and lighting systems meet the criteria for a substantial effort. Electromagnetic emissions only reach the level of mild effort, whereas water sanitation, indoor pollution, and indoor waste management are categorized as general applications. This research is expected to be a reference for evaluating the application of the eco-interior concept in the hospitality industry.

Potential Pollutants and Indoor Air Quality Variables Association towards Implementation of the Breathing Architecture Concept: A Review

Indoor air quality is essential in improving indoor well-being since most people spend their time there. The breathing Architecture concept promotes a strategy for designing indoor space to maintain the indoor air quality. This concept has various challenges, such as indoor pollutants determining the indoor environment to be healthy and decent. This study aims to identify the relationship between IAQ variables related to Breathing Architecture and air pollutants based on secondary sources of past and existing research ten years ago. The review identified 16 articles collected by selecting several relevant keywords in ScienceDirect and screening the title and abstract. Content analysis was conducted to analyze the relationship between IAQ variables and pollutants and their potential association with the breathing architecture concept. The results show that air exchange rate, volume of spaces, relative humidity, and indoor-outdoor temperature are the most potential variables and have a possible relationship while implementing the BA concept. Using these variables, the optimal condition might be perceived since the possibility of lower pollutant contamination might be lower, and the purpose of breathing architecture might be obtained. However, the relationship between other variables and pollutants requires future studies since it is undescribed or may impact other variables.

Nicotiana alkaloids-intervened phospholipid ozonolysis at the air-water interface

Cigarette nicotiana alkaloids associated with lung and cardiovascular diseases attack enormous attention. However, the mechanism at the molecular level between nicotiana alkaloids and phospholipid ozonolysis remains elusive. Herein, we investigated the interfacial ozonolysis of a hung droplet containing 1-palmitoyl-2-oleoyl-sn-phosphatidylglycerol (POPG) intervened by nicotiana alkaloids (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone, NNK; rac-N′-nitrosonornicotine, NNN; nicotine; and (R,S)-N-nitrosoanasabine, NAT) and followed by on-line mass spectrometry analysis. NNK and NNN showed an acceleration on the interfacial ozonolysis, while nicotine and NAT inhibited this chemistry. Such acceleration/inhibition on POPG ozonolysis was positively correlated with nicotiana alkaloid concentrations. The reaction rate constants suggested that the ozonolysis of lung phospholipids exposed to cigarette smoke at the air-water interface occurred rapidly. A possible mechanism of the hydrophilic/oleophilic nature of nicotiana alkaloids mediating the packing density of POPG was proposed. NNK and NNN with a hydrophilic nature inserted into the POPG monolayer loosed the packing, but nicotine and NAT with an oleophilic nature let the POPG closely pack and shield the CC double bonds exposed to ozone (O3). These results gain the knowledge of nicotiana alkaloids mediated phospholipid ozonolysis at the molecule level and provide a method for online interfacial reaction studies associated with elevated indoor pollutants on public health.

Indoor air pollution and cognitive function among older adults in India: a multiple mediation approach through depression and sleep disorders

BackgroundStudies across multiple countries reveal that depression and sleep disorders can lead to cognitive decline. This study aims to speculate on the effect of different sources of indoor air pollution on cognition and to explore the mediation effect of depression and sleep disorders on cognition when exposed to indoor air pollution. We hypothesize that an older adult experiences higher cognitive decline from indoor pollution when mediated by depression and sleep disorders.MethodsWe use data from Longitudinal Aging Study in India (LASI), 2017–2018, and employ a multiple mediation model to understand the relationship between indoor air pollution and cognition through sleep disorders and depression while adjusting for possible confounders. Sensitivity analysis was applied to see the effect of different sources of indoor pollution (cooking fuel, indoor smoke products, and secondhand smoke) on cognitive performance.ResultsThe effect of three sources of indoor pollutants on cognition increased when combined, indicating stronger cognitive decline. Unclean cooking practices, indoor smoke (from incense sticks and mosquito coils), and secondhand smoke were strongly associated with sleep disorders and depression among older adults. Indoor air pollution was negatively associated with cognitive health (β= -0.38) while positively associated with depression (β= 0.18) and sleep disorders (β= 0.038) acting as mediators. Sensitivity analysis explained 45% variability while adjusting for confounders.ConclusionThe study lays a foundation for future investigations into the nexus of indoor pollution and mental health. It is essential to formulate policies to reduce exposure to varying sources of indoor air pollutants and improve screening for mental health services as a public health priority.

Particle size, carbon composition and sources of indoor dust in Nanchang, China

Indoor dust is an enriched environmental media for lots of chemical pollutants, while indoor pollutants pose high exposure level and health risks to humans. In this work, indoor dust samples from four types of indoor environments (residence near steel plant, residence near road, student dormitory and rural kitchen) in Nanchang city were collected and their particle sizes and carbon components were analyzed. The sources of carbon components were traced based on the distribution of carbon components and the correlation between the components. The particle size distribution mainly presents a bimodal mode (0.1–3 and 10–40 μm size intervals, accounting for 8.9% and 7.4%). The average OC and EC in the as-collected indoor dust samples were 34.1 and 52.7 mg/g for residences around the steel plant, 43.9 and 41.4 mg/g for residences adjacent to the road, 119.3 and 66.4 mg/g for students' dormitories, 73.5 and 49.8 mg/g for rural kitchens, respectively. A strong correlation between OC and Char was observed, indicating strong homology between the sources of the two components. In addition, the correlation between two of EC1, OC2, and OC3 (OC2 and OC3 are fractions of OC and EC1 is a fraction of EC) were significant, indicating a large contribution of motor vehicle exhaust to indoor dust. The average ratios of OC/EC and Char/Soot suggest the contribution of automobile exhaust, indoor smoking and biomass combustion to indoor dust. The results of this work provide a scientific, convenient, and reliable approach to explore the source of particulate matter indoors based on the distribution of carbon components.

Formaldehyde degradation using Biofilter loaded with Compost, Vermiculite and Activated Carbon: Performance and Optimization

<p>Formaldehyde is one of the typical indoor pollutants causing theprevalence of acute health issues among those residing in indoor environments. Biofiltrationis a commonly adopted technique to treat indoor air pollutants. In this investigation, a biofilter was fabricated and compactly filled with compost, vermiculite and activated carbon (65:25:10) as a media composition for enhanced formaldehyde degradation. The influence of formaldehyde inlet concentration (0.01 – 1 gm-3g/m3) and EBRT (30 – 180 s) was studied to evaluate the biofilter performance. Their progression was assessed with dynamic operations in five phases with two stages each. The formaldehyde removal was achieved between the range of 32% to 98% with regular intervals of EBRT at 30, 60, 90, 120, 150 and 180 seconds, which depend upon varying their flow rate and inlet loading rate. The biofilter performance lasted for over 202 days with a 98% formaldehyde removal and 23 g/m3h-1biofilter capacity under the maximum EBRT (180 s) and inlet formaldehyde concentration (1 gm-3g/m3). The experimental findings demonstrated the efficacy of biofilter in withstanding substantial formaldehyde loading rate while maintaining an acceptable EBRT. The primary microbe responsible for formaldehyde degradation was identified to be as gram-negative bacteria.</p>

Air Pollution: A Challenge to Public Health and Healthcare Systems

Air Pollution: A Challenge to Public Health and Healthcare Systems

Organic toxicants and emerging contaminants in hospital interiors before and during the SARS-CoV2 pandemic: alkanes and PAHs.

Indoor pollution and deposition dust (DD), in particular, are acquiring concern, due to long exposure time and importance of intake by humans through contact and ingestion. Hospitals look a special category of sites, owing to peculiar contaminants affecting them and to presence of people prone to adverse effects induced by toxicants. Four in-field campaigns aimed at understanding the chemical composition of DD were performed in five Italian hospitals. Measurements were performed before (autumn 2019), during (spring 2021), and after (winter 2022) the peak of SARS-CoV2 and when restrictions caused by pandemic were revoked (winter 2023). Parallel measurements were made outdoors (2022), as well as in a university and a dwelling. Targeted contaminants were n-alkanes and polycyclic aromatic hydrocarbons (PAHs), while iso- and anteiso-alkanes were analyzed to assess the impact of tobacco smoking. Total n-alkanes ranged from 3.9 ± 2.3 to 20.5 ± 4.2mg/g, with higher percentages of short chain homologs in 2019. PAHs ranged from 0.24 ± 0.22 to 0.83 ± 0.50mg/g, with light congeners (≤ 228 a.m.u.) always exceeding the heavy ones (≥ 252 a.m.u.). According to carbon preference indexes, alkanes originated overall from anthropogenic sources. Microorganisms resulted to affect a hospital, and tobacco smoke accounted for ~ 4-20‰ of DD mass. As for PAH sources, the diagnostic concentration ratios suggested the concourse of biological matter burning and vehicle emission. Benzo[a]pyrene equivalent carcinogenic and mutagenic potencies of depositions at hospitals ranged ~ 9-39μg/g and ~ 15-76μg/g, respectively, which seems of concern for health. DD composition in hospitals was different from that outside the premises, as well as that found at university and at dwelling.

Modeling a Smart IoT Device for Monitoring Indoor and Outdoor Atmospheric Pollution

Air pollution is caused by chemical, physical, or biological components alters the fundamental properties of the atmosphere, and contaminates the interior or outdoor settings. With the rapid industrialization activity in recent years, there is an urgent need to monitor air quality. The proposed research provides a mechanism for monitoring air pollution in indoor and outdoor environments. The system consists of an IoT-based Arduino device. The Arduino IDE connects the Temperature and Humidity sensor, Grove light sensor, and air quality sensor to measure the air pollutants such as Carbon dioxide CO2, Nitrogen oxide (NOx), and Particulate Matter PM2.5. The sensors work efficiently and provide qualitative findings from the environment when they are exposed to CO2, gasoline, solvents, thinner, formaldehyde, and other harmful chemicals. The Wi-Fi module of the Blues Wireless Notehub is used for secure data routing to the IoT cloud. The Air Quality Index (AQI) measures provide information on whether there is something unsafe in indoor and outdoor environments. For collecting and analyzing the device data, the Notecard is intended to be used with a cloud storage service. Also, the indoor fire detector identifies the incident of fire intimates the users through the alarm, and measures the indoor pollutant at that time. The proposed smart IoT product model would be an excellent device for air quality monitoring because of its long-term consistency and low electricity consumption.

Air change per hour improvement for positive and negative pressure mechanical ventilation facilities systems

Ventilation reduces indoor pollutants, and this issue has recently received attention. Most scholars adopt ventilation strategies to reduce energy consumption. While natural ventilation does not require ventilation facilities, it also brings many challenges, such as lack of external openings and insufficient air change per hour. Therefore, it is necessary to rely on mechanical ventilation to increase indoor air change per hour. However, mechanical ventilation comes with increased energy consumption, which poses a significant challenge to reducing energy usage at present.To improve energy usage, increase air changes per hour, and reduce the number of fans by half, we propose implementing positive and negative pressure ventilation indoors at the same airflow rate (3000 CMH). The research results showed that positive and negative pressure ventilation increased air changes per hour by 94 % and 62 %, respectively, while also reducing fan energy usage by 50 %. Through visualization, we also discovered the uneven distribution of indoor carbon dioxide levels. This breakthrough is of significant importance for current indoor mechanical ventilation systems and contributes greatly to future near-zero carbon emissions.

Indoor Air Pollution: A Review on the Challenges in Third World Countries

Background: The challenges of third-world countries toward curbing indoor air pollution seem insurmountable as its solution is closely linked to their economic incapacities, lifestyle, and existing outdoor air quality. The economic incapacities include types of the cookstove, fuel sources, types of insecticides and pesticides, building patterns, indoor fermentation activities (such as leaving dirty plates and biological waste in the house for a long time), and regulation on the use of deodorants. Aside from the common pollutants from these sources, the reactive chemistry of pollutants leads to other kinds of pollutants which have been reported to be short-lived but dangerous. Objectives: The objectives of the study are to: profile emerging indoor pollutants; examine the pollutant dynamics and their impact on unplanned regions of developing countries; offer solutions to curb indoor pollution in the identified region; elaborate on the cost analysis of existing solutions and how irrelevant they may be due to the rising poverty index; and project how government policies could help in reducing indoor pollution. Design: This paper is a review that wholistically examined indoor pollution. A total of fifty-six articles was reviewed in addition to the data obtained from MERRA-2. Results: The study observed that indoor air pollution dynamics are more complex—compared to outdoor air pollution. It was observed that the possibility to control indoor air pollution is based on the type of pollutants, the reactive chemistry of the pollutants, and ventilation in the building. This review shows that poverty is one of the many reasons why indoor air pollution would be a source of menace for a long time in third-world countries. Several solutions to curbing indoor air pollution were considered with a principal focus on cost and availability. Limitations: Most experimental results that were used to corroborate postulates were obtained from the literature. The accuracy of those experiments and the sensitivity of the equipment used cannot be verified. Conclusion: The plant-based technique was identified as a perfect solution to indoor air pollution control in third-world countries but the local architecture and lifestyle of most third-world countries constitute a threat to its adoption. It was observed that less than 8% of third-world countries have specific Air Quality Acts which have not been amended for decades. Most third-world countries have a general Environmental Act with air quality as a sub-section in the Act with very low fines for violators. The inclusion of indoor air quality as a vital public health issue in third-world countries is necessary for the preservation of lives and posterity.

Indoor cooking and cleaning as a source of outdoor air pollution in urban environments.

Indoor sources of air pollution, such as from cooking and cleaning, play a key role in indoor gas-phase chemistry. The focus of the impact of these activities on air quality tends to be indoors, with less attention given to the impact on air quality outside buildings. This study uses the INdoor CHEmical Model in Python (INCHEM-Py) and the Advanced Dispersion Modelling System (ADMS) to quantify the impact cooking and cleaning have on indoor and outdoor air quality for an idealised street of houses. INCHEM-Py has been developed to determine the concentrations of 106 indoor volatile organic compounds at the point they leave a building (defined as near-field concentrations). For a simulated 140 m long street with 10 equi-distant houses undertaking cooking and cleaning activities, the maximum downwind concentration of acetaldehyde increases from a background value of 0.1 ppb to 0.9 ppb post-cooking, whilst the maximum downwind chloroform concentrations increase from 1.2 to 6.2 ppt after cleaning. Although emissions to outdoors are higher when cooking and cleaning happen indoors, the contribution of these activities to total UK emissions of volatile organic compounds is low (less than 1%), and comprise about a quarter of those emitted from traffic across the UK. It is important to quantify these emissions, particularly as continued vehicle technology improvements lead to lower direct emissions outdoors, making indoor emissions relatively more important. Understanding how indoor pollution can affect outdoor environments, will allow better mitigation measures to be designed in the future that can take into account all sources of pollution that contribute to human exposure.

Characteristics Analysis of CO2 Concentrations and Temperature in Residential Buildings in Severe Cold Area Based on Field Measurement

This paper provides references for the design and control of high-quality green building indoor environments during the transitional season in severe cold area. A residential building in severe cold area was selected as the research subject, where indoor pollutant CO2 concentrations and temperatures were measured at the beginning of the transitional season. The study explored the variations in indoor pollutant temperatures and CO2 concentrations under natural and non-natural ventilation conditions, in conjunction with an analysis of the occupants' activities. The results demonstrated clear relationships between indoor pollutant CO2 concentrations and temperatures under natural ventilation conditions. Based on these findings, recommendations for natural ventilation strategies that consider both indoor CO2 levels and thermal environment are proposed.

TFOS lifestyle report: Effects of environmental conditions on the ocular surface

This presentation summarizes the findings of the Environmental Conditions Subcommittee of the recent Workshop of the Tear Film & Ocular Surface Society, entitled “A Lifestyle Epidemic: Ocular Surface Disease” (www.tearfilm.org). The tear film and the ocular surface morphofunctional unit are directly exposed to the surrounding environment. Environmental factors with potential, probable or well‐established impact on the ocular surface health include: climate factors (temperature, humidity, windspeed, altitude, dew point, ultraviolet light), outdoor and indoor pollutants (gases, particulate matter, and airborne pollutants) and allergens. These factors interact each other in complex and concurrent ways, contributing to different specific ocular surface diseases, including dry eye, ocular allergies, conjunctival and corneal degenerative conditions, injuries, and neoplastic diseases. Age and sex, race/ethnicity, geographical area, and seasonality are some of the key elements playing a relevant role in environmental factors‐related ocular surface diseases.Throughout an extensive narrative review process, this report evaluated in detail the evidence about each of those environmental conditions and the associated ocular surface diseases. Distinct environmental conditions may increase risk and/or aggravate certain conditions and may contribute to specific diseases. Indeed, a systematic review, conducted to investigate the association between outdoor pollution and dry eye signs and symptoms, found evidence supporting the risk factor role of air pollution (from NO2 and CO, but not from PM10) and soil pollution (from chromium).

Sick building syndrome: do outdoor pollutants and pollen affect it?

Sick building syndrome (SBS) refers to non-specific complaints, including upper-respiratory irritative symptoms, headaches, fatigue, and rash, which are usually associated with a particular building by their temporal pattern of occurrence and clustering among inhabitants or colleagues. The aim of the study was to determine the association between the clinical manifestations of sick building syndrome with outdoor pollutants and airborne pollen. It was a descriptive and prospective observational study conducted from November 2021 to April 2022. It included subjects over 18 years old who completed an online survey on sick building syndrome (general symptoms, nasal, ocular, oropharyngeal, and skin symptoms) presented at home, housing information and personal history. The APS-330 from Pollen Sense ® was used to obtain data on pollen in the air and the local pollution monitoring system (SIMA) to obtain information regarding pollutants. For statistical analysis, SPSS version 16 was used. A total of 402 surveys were included; 91% of the subjects reported having at least 1 symptom. Females presented more general symptoms (fatigue and headache) than males. Subjects with a personal history of atopy showed a higher prevalence of practically all symptoms. Airborne pollen exposure was positively associated with mucosal symptoms in eyes and nose. Outdoor fungi spore exposure was positively associated with oculo-nasal and cutaneous symptoms in the scalp. This study found significant associations with female gender and a history of atopy, which suggests a higher risk for these subjects. Despite the limitations of the study, we can conclude that there is an association between the clinical manifestations of sick building syndrome with indoor and outdoor pollution.

The chemical assessment of surfaces and air (CASA) study: using chemical and physical perturbations in a test house to investigate indoor processes.

The Chemical Assessment of Surfaces and Air (CASA) study aimed to understand how chemicals transform in the indoor environment using perturbations (e.g., cooking, cleaning) or additions of indoor and outdoor pollutants in a well-controlled test house. Chemical additions ranged from individual compounds (e.g., gaseous ammonia or ozone) to more complex mixtures (e.g., a wildfire smoke proxy and a commercial pesticide). Physical perturbations included varying temperature, ventilation rates, and relative humidity. The objectives for CASA included understanding (i) how outdoor air pollution impacts indoor air chemistry, (ii) how wildfire smoke transports and transforms indoors, (iii) how gases and particles interact with building surfaces, and (iv) how indoor environmental conditions impact indoor chemistry. Further, the combined measurements under unperturbed and experimental conditions enable investigation of mitigation strategies following outdoor and indoor air pollution events. A comprehensive suite of instruments measured different chemical components in the gas, particle, and surface phases throughout the study. We provide an overview of the test house, instrumentation, experimental design, and initial observations - including the role of humidity in controlling the air concentrations of many semi-volatile organic compounds, the potential for ozone to generate indoor nitrogen pentoxide (N2O5), the differences in microbial composition between the test house and other occupied buildings, and the complexity of deposited particles and gases on different indoor surfaces.

Colorimetric and dynamic light scattering dual-readout assay for formaldehyde detection based on the hybridization chain reaction and gold nanoparticles

A novel colorimetric and dynamic light scattering dual-readout assay for FA detection was developed based on the HCR by using AuNPs.

Investigation of Indoor Airborne Bacteria in the Severe Cold Region in China: Genera, Levels, and the Influencing Factors of Concentration

In regions experiencing severe cold, inadequate ventilation during winter months often leads to increased concentrations of indoor pollutants. While there have been several studies on indoor particulate matter and inorganic pollutants in such regions, bioaerosol pollution has not been as extensively investigated. This study examines the indoor bioaerosol situation in a university located in one of the severe cold regions in China, focusing on bacteria as a representative pollutant. It investigated random samples of an office and a dormitory (including washrooms) and spanned heating and nonheating periods. The findings indicated that bacterial abundance in the dormitory and office was approximately equivalent. The predominant airborne bacterial communities identified were Proteobacteria, Bacteroidota, Actinobacteriota, Firmicutes, and Myxococcota. Opening windows effectively reduced bacterial concentrations during both heating and nonheating periods. When windows remained closed, bacterial concentrations exceeded the standard by 9.1% during the nonheating period and by 14.3% during the heating period. Furthermore, temperature and relative humidity influenced bacterial particle size, activity, and consequently, aerosol concentrations. In the office, the highest percentage of bioaerosols was observed in particle sizes <1.1 and 1.1–2.1 μm, with smaller percentages observed in other particle sizes. Conversely, the percentage of particle sizes 2.1–3.3 μm in the dormitory was higher. The highest bacterial aerosol concentrations were detected in the morning in both the dormitory and office, during heating and nonheating periods. Bacterial concentrations in the office were lower on weekends than on weekdays, whereas in the dormitory, concentrations were higher on weekends than on weekdays. The above results indicate that indoor bacterial aerosol pollution is serious in winter in severe cold regions, which needs more attention.