Outdoor Pollution Levels Research Articles

Indoor Air Quality at an Urban Primary School in Madrid (Spain): Influence of Surrounding Environment and Occupancy.

Monitoring indoor air quality (IAQ) in schools is critical because children spend most of their daytime inside. One of the main air pollutant sources in urban areas is road traffic, which greatly influences air quality. Thus, this study addresses, in depth, the linkages of meteorology, ambient air pollution, and indoor activities with IAQ in a traffic-influenced school situated south of Madrid. The measurement period was from 22 November to 21 December 2017. Simultaneous measurements of indoor and outdoor PM1, PM2.5, and PM10 mass concentrations, ultrafine particle number concentration (PNC) and equivalent black carbon (eBC) were analyzed under different meteorological conditions. PNC and eBC outdoor concentrations and their temporal trend were similar among the sampling points, with all sites being influenced in the same way by traffic emissions. Strong correlations were found between indoor and outdoor concentrations, indicating that indoor pollution levels were significantly affected by outdoor sources. Especially, PNC and eBC had the same indoor/outdoor (I/O) trend, but indoor concentrations were lower. The time delay in indoor vs. outdoor concentrations varied between 0.5 and 2 h, depending on wind speed. Significant differences were found between different meteorological conditions (ANOVA p-values < 2.14 × 10-6). Atmospheric stability periods led to an increase in indoor and outdoor pollutant levels. However, the highest I/O ratios were found during atmospheric instability, especially for eBC (an average of 1.2). This might be related to rapid changes in the outdoor air concentrations induced by meteorology. Significant variations were observed in indoor PM10 concentrations during classroom occupancy (up to 230 µg m-3) vs. non-occupancy (up to 19 µg m-3) days, finding levels higher than outdoor ones. This was attributed to the scholarly activities in the classroom. Conversely, PNC and eBC concentrations only increased when the windows of the classroom were open. These findings have helped to establish practical recommendations and measures for improving the IAQ in this school and those of similar characteristics.

Balance point concentration: An indicator for classroom performance against outdoor PM2.5

Indoor air quality significantly affects occupants' health, making it crucial to evaluate a building's vulnerability to air pollution. In this study, 17 classrooms in urban areas of Seoul, Korea were monitored to determine how long a clean air environment can be maintained. We propose the balance point concentration (BPC) as the threshold value of outdoor PM2.5 concentration that can maintain PM2.5 in classrooms at the target value of 15 μg/m3. Based on the mass-balance equation, BPC is a comprehensive indicator that considers PM2.5 that can penetrate through building envelope, be generated from indoor activities, and be removed by an air purification system. For non-occupied classrooms, the BPC ranged from 20.6 to 34.3 μg/m3. We find that better airtightness reduced air pollution in buildings. However, due to students' activities, BPC decreased to 7.6–12.0 μg/m3. Lastly, in classrooms with mechanical ventilation systems in operation, the BPC ranged from 24.3 to 34.2 μg/m3, showing improved performance. Under such conditions, students can spend more than 88 % of the year in a classroom environment with clean air. In areas with low outdoor pollution levels, satisfaction can be even higher. Evaluating buildings performance using BPC allows for a more intuitive and clear assessment compared to existing indicators. When outdoor concentrations exceed BPC, additional air quality management in the classroom is necessary. This can be widely utilized when planning improvements to the environment or the operation of air purification system.

Evaluating Indoor Air Quality in Schools: Is the Indoor Environment a Haven during High Pollution Episodes?

Pollution data were collected at five schools in Hong Kong using low-cost, sensor-based monitors both indoors and outdoors during two consecutive high pollution episodes. The pollutants monitored included NO2, O3, PM2.5, and PM10, which were also used as input to a health risk communication protocol known as Air Quality Health Index (AQHI). CO2 was also measured simultaneously. The study aimed to assess the relationship between indoor pollutant concentrations and AQHI levels with those outdoors and to evaluate the efficacy of building operating practices in protecting students from pollution exposure. The results indicate that the regular air quality monitoring stations and outdoor pollutant levels at schools exhibit similar patterns. School AQHI levels indoors were generally lower than those outdoors, with PM10 levels showing a larger proportional contribution to the calculated values indoors. NO2 levels in one school were in excess of outdoor values. CO2 monitored in classrooms commonly exceeded indoor guidelines, suggesting poor ventilation. One school that employed air filtration had lower indoor PM concentrations compared to other schools; however, they were still similar to those outdoors. O3 levels indoors were consistently lower than those outdoors. This study underscores the utility of on-site, sensor-based monitoring for assessing the health impacts of indoor and community exposure to urban air pollutants. The findings suggest a need for improved ventilation and more strategic air intake placement to enhance indoor air quality.

Short-Term Exposure to Air Pollution and the Incidence and Mortality of Stroke: A Meta-Analysis.

The relationship between short-term exposure to various air pollutants [particulate matter <10 μm (PM 10 ), particulate matter <2.5 μm (PM 2.5 ), nitrogen dioxide (NO 2 ), sulfur dioxide (SO 2 ), carbon monoxide, and ozone (O 3 )] and the incidence and mortality of stroke remain unclear. We conducted a comprehensive search across databases, including PubMed, Web of Science, and others. A random-effects model was employed to estimate the odds ratios (OR) and their 95% CIs. Short-term exposure to PM 10 , PM 2.5 , NO 2 , SO 2 , and O 3 was associated with increased stroke incidence [per 10 μg/m 3 increase in PM 2.5 : OR = 1.005 (95% CI: 1.004-1.007), per 10 μg/m 3 increase in PM 10 : OR = 1.006 (95% CI: 1.004-1.009), per 10 μg/m 3 increase in SO 2 : OR = 1.034 (95% CI: 1.020-1.048), per 10 μg/m 3 increase in NO 2 : OR = 1.029 (95% CI: 1.015-1.043), and O 3 for per 10 μg/m 3 increase: OR: 1.006 (95% CI: 1.004-1.007)]. In addition, short-term exposure to PM 2.5 , PM 10 , SO 2, and NO 2 was correlated with increased mortality from stroke [per 10 μg/m 3 increase in PM 2.5 : OR = 1.010 (95% CI: 1.006-1.013), per 10 μg/m 3 increase in PM 10 : OR = 1.004 (95% CI: 1.003-1.006), per 10 μg/m 3 increase in SO 2 : OR = 1.013 (95% CI: 1.007-1.019) and per 10 μg/m 3 increase in NO 2 : OR = 1.012 (95% CI: 1.008-1.015)]. Reducing outdoor air pollutant levels may yield a favorable outcome in reducing the incidence and mortality associated with strokes.

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.

How teacher behaviors and perceptions, air change rates, and portable air purifiers affect indoor air quality in naturally ventilated schools.

Many school buildings have inadequate ventilation, rudimentary if any air filtration, and aging and poorly maintained mechanical systems, all of which can lead to poor indoor air quality (IAQ). These issues are especially acute in environmental justice (EJ) communities where schools are located in polluted areas. This community-based participatory research examines how IAQ in naturally ventilated school buildings is affected by the use of air purifiers, air change rates, outdoor pollution levels, and teacher and staff behavior. IAQ assessments were performed at two schools in Detroit, Michigan, which included building walk-through inspections and continuous indoor and outdoor measurements of black carbon (BC), particulate matter (PM10 and PM2.5), carbon dioxide (CO2), air change rates (ACRs), temperature, humidity, and sound pressure levels. Air purifiers with usage monitors were then installed, and the IAQ assessments were repeated. Teachers were surveyed before and after purifier deployment. At baseline, classrooms had low ACRs (0.58-1.38 h-1), moderate PM2.5 levels (2.8-8.9 μg/m3), highly variable PM10 concentrations (4.7-37.5 μg/m3), and elevated BC levels (0.3-0.7 μg/m3), reflecting emissions from local traffic, industry and other sources. The installation and use of purifiers reduced pollutant levels and the overall performance matched the predictions of a single compartment model. However, daily reductions varied widely among classrooms, reflecting differences in teacher behavior regarding the frequency of opening windows and the operation of purifiers, including differences in purifier fan speed settings and whether purifiers were used at night. Survey responses indicated that many teachers were aware of IAQ problems. The higher rates reported for health symptoms and dissatisfaction at one school may have lowered the teachers' tolerance to noise and reduced purifier use. The study helps explain the variation reported in prior studies using purifiers, and it reinforces the need to monitor IAQ and purifier use, use enhanced filtration and increase ventilation, and engage with teachers and school staff to support and maintain IAQ programs in schools.

22 Development of an Integrated Exposure Pathway Model for Health Impact Assessment of Traffic Ultrafine Particles (H2020 Ultrhas-Project)

Abstract Recently, the causal associations between traffic emissions and health effects were strengthened by the systematic reviews by the Health Effects Institute (HEI#23, 2022). According to EuroStat data Europeans spend 87-97% of their time indoors in homes, workplaces, schools and nurseries. Breathing volumes are dominated by the time spent indoors (16 m³ indoors and 1.4 m³ outdoors), even though breathing rates in outdoor environments are higher. This demonstrates the importance of taking into account time activity as well as infiltration to indoor spaces when estimating intake of particles. The ULTRHAS project aims to link in vitro toxicological evidence for particulate matter to health impact assessments to look specifically into this. An integrated exposure pathway model will consider for different microenvironments, and physical activity patterns to quantify the particle intake in selected gender and age groups. Relative to the commonly applied approach using residential address and corresponding outdoor pollution levels we specifically add handling of (i) infiltration into indoor spaces and (ii) variability in breathing volumes based on physical activities. The model will provide inhalation volumes for selected target populations, to be applied in the intake-DALY estimation of burden of disease parameters in the following phases of the project.

Indoor Air Pollution and the Health of Vulnerable Groups: A Systematic Review Focused on Particulate Matter (PM), Volatile Organic Compounds (VOCs) and Their Effects on Children and People with Pre-Existing Lung Disease

Air pollution affects health, but much of the focus to this point has been on outdoor air. Higher indoor pollution is anticipated due to increasingly energy-efficient and less leaky buildings together with more indoor activities. Studies of indoor air pollution focusing on children and people with respiratory disease from the database Web of Science (1991–2021) were systemically reviewed according to the PRISMA guidelines, with 69 studies included in the final selection. Emissions from building materials affected indoor air quality, and ventilation also had an influence. The main indoor air pollutants are Volatile Organic Compounds (VOCs) and Particulate Matter (PM). PM sources included smoking, cooking, heating, candles, and insecticides, whereas sources of coarse particles were pets, housework and human movements. VOC sources included household products, cleaning agents, glue, personal care products, building materials and vehicle emissions. Formaldehyde levels were particularly high in new houses. Personal exposure related to both indoor and outdoor pollutant levels, highlighting home characteristics and air exchange rates as important factors. Temperature, humidity, educational level, air purifiers and time near sources were also related to personal exposure. There was an association between PM and Fractional exhaled Nitric Oxide (FeNO), lung function, oxygen saturation, childhood asthma and symptoms of chronic obstructive pulmonary disease (COPD) patients. High VOCs were associated with upper airways and asthma symptoms and cancer. Effective interventional studies for PM in the future might focus on human behavior together with air purifiers and increased ventilation, whereas VOC interventions might center more on building materials and household products, alongside purification and ventilation.

Air quality in underground metro station commuter platforms in Singapore: A cross-sectional analysis of factors influencing commuter exposure levels

The metro is a major component of public transport systems in urbanized cities and may expose commuters to indoor air pollutants. We examined how commuter exposure to indoor air pollutant levels varied with the characteristics of underground metro stations. We carried out a national study of 41 commuter platforms from 39 randomly selected underground stations in Singapore. We used generalized linear models to assess the variability of air pollutant concentrations with station characteristics. We computed commuter-weighted pollutant-specific station rankings to inform mitigation priority. PM2.5 (mean = 24.1 μg/m3) and PM10 (mean = 26.9 μg/m3) concentrations across commuter platforms were generally lower than those found outdoors while platform CO2 levels (mean = 608.1 ppm) were 1.7 times those outdoors. More stations exceeded the WHO 24-h mean exposure guidelines values for PM2.5 (n = 30, 73%) than for PM10 (n = 4, 10%). PM2.5, PM10 and CO2 levels were lowest in stations on the Circle, North-East and Downtown lines. PM2.5 and PM10 concentrations at platforms were positively associated with their outdoor concentrations. Mean CO2 concentration levels at platforms were the highest during commuter rush hours. Longer train arrival intervals were associated with lower CO2 levels. PM2.5 and PM10 levels in stations were negatively associated with the depth of the commuter platforms. Commuter volumes influenced the priority ranking of mitigation measures. Underground metro stations exhibited high variability and dependence on station characteristics as well as outdoor ambient pollutant levels. Our study findings suggest that any required improvements in ventilation and station design should be focused on PM2.5 exposure reduction and prioritized according to both indoor air pollutant levels and commuter volumes to provide the largest extent of commuter benefits.

Carbon monoxide's potential comeback as a key air pollutant

In The Lancet Planetary Health, Kai Chen and colleagues present an impressive study on the potential effects of short-term exposure to carbon monoxide (CO) on mortality.1 Health effects of very high CO concentrations have been well documented,2 but it is less clear whether mortality effects still occur at the current, much lower outdoor pollution levels. Chen and colleagues collected daily data on all-cause mortality and air pollution from 337 cities around the world within the Multi-Country Multi-City Collaborative Research Network.

Lung Health in Children in Sub-Saharan Africa: Addressing the Need for Cleaner Air.

Air pollution is increasingly recognized as a global health emergency with its impacts being wide ranging, more so for low- and middle-income countries where both indoor and outdoor pollution levels are high. In Africa, more than 80% of children live in households which use unclean sources of energy. The effects of both indoor and outdoor pollution on lung health on children who are the most vulnerable to their effects range from acute lower respiratory tract infections to long-term chronic health effects. We reviewed the literature on the effects of air pollution in children in Sub-Saharan Africa from prenatal exposure, infancy and school-going children. Data from Sub-Saharan Africa on quantification of exposures both indoor and outdoor mainly utilizes modelling or self-reporting. Exposures to biomass not only increases the risk of acute respiratory tract infections in young children but also increases the risk of carriage of pathogenic bacteria in the upper respiratory tract. Although there is limited evidence of association between asthma and pollution in African children, airway hyper-responsiveness and lower lung function has been demonstrated in children with higher risk of exposure. Interventions at a policy level to both quantify the exposure levels at a population level are urgently needed to address the possible interventions to limit exposure and improve lung health in children in Sub-Saharan Africa.

Comparison of Air Quality in Kuwait Urban and Industrial Areas

This paper describes the research carried out to investigate air quality in Kuwait. It examined the results of several years of pollutants data provided by Kuwait Environment Public Authority. The data were obtained from a number of fix monitoring stations. The results of the time series analysis have shown that monitored exposures vary substantially and are unique to the location and temporal variation of the measured site (background, urban area, industry area and refinery area). Also, outdoor pollutant levels were governed more by the characteristics of traffic rather than level of flow and traffic.

An Exposure Appraisal of Outdoor Air Pollution on the Respiratory Well-being of a Developing City Population

Zaria is the educational hub of northern Nigeria. It is a developing city with a pollution level high enough to be ranked amongst the World Health Organization’s (WHO) most polluted cities. The study appraised the influence of outdoor air pollution on the respiratory well-being of a population in a limited resource environment. With the approved ethics, the techniques utilized were: portable pollutant monitors, respiratory health records, WHO AirQ+ software, and the American Thoracic Society (ATS) questionnaire. They were utilized to acquire day-time weighted outdoor pollution levels, health respiratory cases, assumed baseline incidence (BI), and exposure respiratory symptoms among selected study participants respectively. The study revealed an average respiratory illness incidence rate of 607 per 100,000 cases. Findings showed that an average of 2648 cases could have been avoided if the theoretical WHO threshold limit for the particulate matter with diameter of <2.5/10 micron (PM2.5/PM10) were adhered to. Using the questionnaire survey, phlegm was identified as the predominant respiratory symptom. A regression analysis showed that the criteria pollutant PM2.5, was the most predominant cause of respiratory symptoms among interviewed respondents. The study logistics revealed that outdoor pollution is significantly associated with respiratory well-being of the study population in Zaria, Nigeria.

Potential reductions in premature mortality attributable to PM2.5 by reducing indoor pollution: A model analysis for Beijing-Tianjin-Hebei of China

BackgroundChina has one of the highest PM2.5 (particulate matter with an aerodynamic diameter smaller than 2.5 μm) pollution levels in the world. It might still be long before air quality reaches the National Class II standard of 35 μg/m3. ObjectiveWe aim to estimate the potential reduction in premature mortality by reducing indoor PM2.5 levels in the Beijing-Tianjin-Hebei (BTH) region and compare it with reducing outdoor levels. MethodsWe combined PM2.5 transport model and the Global Burden of Disease (2016) methodology to estimate potential reductions in premature mortality attributable to PM2.5 by reducing indoor PM2.5 to National Class I standard of 15 μg/m3, and compared with reducing outdoor PM2.5 to Government 2020 Interim target of 64 μg/m3 or National Class II standard of 35 μg/m3. ResultsA total of 74,000 (95% confidence interval (CI): 43,000–111,000) premature deaths were attributable to PM2.5 exposure in 2013. Thirty percent, or 22,000 (95% CI: 17,000–32,000) deaths, would have been averted if indoor PM2.5 had reached the National Class I standard. The benefit is greater than that from reaching the Government 2020 Interim target for outdoor PM2.5 [22%, or 16,000 (95% CI: 12,000–23,000), deaths], although still smaller than that from reaching the National Class II standard [42%, or 31,000 (95% CI: 24,000–45,000), deaths]. ConclusionsReaching the National Class I level of indoor PM2.5 at current outdoor pollution levels could bring considerable health benefits, which are comparable to those from reaching the Government 2020 Interim target for outdoor PM2.5. Main findingsThe avertable premature deaths gained from cleaning indoor PM2.5 to National Class I standard level would be greater than reducing outdoor PM2.5 to Government 2020 Interim target.

A comprehensive air quality investigation at an aquatic centre: Indoor/outdoor comparisons.

Air quality and comfort parameters in a naturally ventilated aquatic centre were studied in relation to the outdoor pollution levels. Simultaneous measurements of PM 2.5, as well as of volatile organic compounds, were carried out for the indoor and outdoor environment of the aquatic centre. The chemical analysis of ionic species and trace elements associated with particulate matter was also performed. In addition, automated analyzer for NO2 and O3 was used in order to record the indoor and outdoor levels of these pollutants. Analysis of diurnal variation of the pollutants' concentration was applied to the collected data, allowing the identification of potential variation on the sources affecting the indoor air quality. PM 2.5 concentration was almost two times higher indoors than outdoors with average values of 13.96 and 6.78μg/m3, respectively. Concerning the ion fraction of PM 2.5, SO42- and Ca2+ were the ions with higher concentration indoors with values of 1.06 and 0.93μg/m3, respectively, while the percentage of Cl- to the PM 2.5 fraction of the indoor atmosphere (9%) was too high than outdoor ones (1%). These results showed that indoor air of swimming pool concerning PM 2.5 and ionic species is mainly affected by the chlorination process along with the comfort conditions (high relative humidity) created during the operation of the facility. The common volatile organic compound concentrations at indoor air are generally in higher levels, compared to the outdoor air with p,m-xylene and toluene to be the substances with the higher concentration for indoor and outdoor area, respectively (7.80 and 1.57μg/m3); nevertheless, values were rather low compared with the findings of other studies. Also, they clearly demonstrate a diurnal variation as a result of poor ventilation during night. As it was expected, chloroform showed the highest concentration compared to the other volatile organic compounds with values ranging from 3.35 to 135.89μg/m3, with an average of 54.50μg/m3. Concerning the NO2 concentration, indoor levels showed an increased pattern when the swimming pool was fully occupied, a fact that reveals a possible correlation. As an overall conclusion, the natural ventilation and the disinfection process seem to play a key role to the air quality of the indoor air of the aquatic centre.

The Effects of Outdoor Source on Pollution Characteristics and Dynamic Changes of Particulate Matter in an Office

The indoor air quality has a direct impact on human health. Particulate matter is one of the important factors affecting the indoor air quality. The paper selects an office as the study object and studies the pollution characteristics and dynamic changes of indoor particulate matter in different outdoor pollution levels. The mass concentration of outdoor PM10 is used as the evaluation basis of the outdoor pollution level. The outdoor PM10 concentration levels are divided into the range of 200–300, 300–400, 400–500, 500–600, 600–700 μg·m−3, individually. Firstly, the change characteristics of the mass concentration and the number concentration of the particulate matter in the five outdoor conditions are analyzed. Secondly, the maximum increase values and the maximum increase rates of the mass concentrations of different particle sizes in the five conditions are compared. Then, the penetration factors of the particulates in different sizes are compared among the five conditions. Finally, the correlation between indoor particulate matter and outdoor particulate matter is studied. The study results show that the effect of outdoor infiltration has a great influence on the indoor PM1 mass concentration, and the penetrating factors of the particulate matter between 0.3 μm and 0.5 μm are higher than 0.6; their permeability is the most obvious.

Indoor air quality and wildfire smoke impacts in the Pacific Northwest

Efforts to improve energy efficiency in homes and buildings have led to tighter structures. However, these changes can also produce negative consequences for indoor air quality and human health. One of the dramatic effects of climate change and weather is the increase in destructive wildfires, such as those experienced in the Pacific Northwest during the summer of 2015. The current article presents data for measurements at two houses during periods with and without high levels of wildfire smoke outdoors. For each house, indoor and outdoor pollutant measurements were obtained for ozone (O3), fine particulate matter (PM2.5), and volatile organic compounds along with outdoor weather conditions and occupant activities including the use of windows and doors. The volatile organic compound measurements were obtained using a Proton Transfer Reaction Mass Spectrometer. Compounds monitored included acetonitrile (a biomass burning tracer), formaldehyde, acetaldehyde, methanol, acetone, benzene, toluene, and C2-alkylbenzenes (i.e., sum of xylenes and ethylbenzene), C3-alkylbenzenes (i.e., sum of trimethylbenzene, ethyltoluene, and propylbenzene isomers), and C4-alkylbenzenes (i.e., sum of tetramethylbenzene and its isomers). A carbon dioxide tracer method was used to measure in situ ventilation rates, and blower door tests were also completed to determine standard ventilation rates. For smoky periods with elevated outdoor pollutant levels, penetration factors, defined as the ratio of indoor/outdoor concentrations were quite low. Penetration factors for PM2.5 were 11% for H2 and 15% for H3, except when windows or doors were open. The penetration factors for O3 were also low at 24% for H2 and 5% for H3. Elevated indoor volatile organic compound levels were not typically associated with outdoor levels, but reflected significant indoor sources. During smoke events, acetonitrile, a biomass burning tracer compound, was elevated outdoors and indoors in both houses, and benzene was elevated outdoors and indoors in H3.

An Experiment with Air Purifiers in Delhi during Winter 2015-2016.

Particulate pollution has important consequences for human health, and is an issue of global concern. Outdoor air pollution has become a cause for alarm in India in particular because recent data suggest that ambient pollution levels in Indian cities are some of the highest in the world. We study the number of particles between 0.5μm and 2.5μm indoors while using affordable air purifiers in the highly polluted city of Delhi. Though substantial reductions in indoor number concentrations are observed during air purifier use, indoor air quality while using an air purifier is frequently worse than in cities with moderate pollution, and often worse than levels observed even in polluted cities. When outdoor pollution levels are higher, on average, indoor pollution levels while using an air purifier are also higher. Moreover, the ratio of indoor air quality during air purifier use to two comparison measures of air quality without an air purifier are also positively correlated with outdoor pollution levels, suggesting that as ambient air quality worsens there are diminishing returns to improvements in indoor air quality during air purifier use. The findings of this study indicate that although the most affordable air purifiers currently available are associated with significant improvements in the indoor environment, they are not a replacement for public action in regions like Delhi. Although private solutions may serve as a stopgap, reducing ambient air pollution must be a public health and policy priority in any region where air pollution is as high as Delhi’s during the winter.

Indoor Air Quality.

Many health care providers are concerned with the role environmental exposures play in the development of respiratory disease. While most individuals understand that outdoor air quality is important to their health status, many are unaware of the detrimental effects indoor air pollution can potentially have on them. The Environmental Protection Agency (EPA) regulates both outdoor and indoor air quality. According to the EPA, indoor levels of pollutants may be up to 100 times higher than outdoor pollutant levels and have been ranked among the top 5 environmental risks to the public. There has been a strong correlation between air quality and health, which is why it is crucial to obtain a complete environmental exposure history from a patient. This article focuses on the effects indoor air quality has on the respiratory system. Specifically, this article will address secondhand smoke, radon, carbon monoxide, nitrogen dioxide, formaldehyde, house cleaning agents, indoor mold, animal dander, and dust mites. These are common agents that may lead to hazardous exposures among individuals living in the United States. It is important for health care providers to be educated on the potential risks of indoor air pollution and the effects it may have on patient outcomes. Health problems resulting from poor indoor air quality are not easily recognized and may affect a patient's health years after the onset of exposure.

Organizational Strategies to Manage Expatriate Worries about Pollution Levels in Megacities

&lt;p style="margin: 0cm 0cm 4pt; text-align: justify; line-height: 12pt; mso-line-height-rule: exactly;"&gt;The purpose of this paper is to analyse how a large European infrastructure developer responded to expatriate worries about high outdoor pollution levels in the Indian megacity Delhi. We present an exploratory case study obtained from a three months project with close university/company interaction, both with the head office in Oslo Norway and the Delhi office. Fact assessment showed that pollution levels are high and rising, with significant expected increase in asthma, cardiac diseases and mortality in the winter months. The results show that the employees compare home office environment with the Delhi office, and compare the company actions plans with other companies’ problem solving initiatives. Cost considerations were not important in the development of the response plan but in the implementation phase (specific decisions) and the results further shows that the characteristics of the internal process are important. We present a company response plan to a real-life situation, and this plan could be used by other companies as well. From the company perspective, the paper points towards a challenging issue of similar or dissimilar handling of local employees versus expatriates. Destination characteristics such as air pollution have attained limited focus in expatriate research, and a major contribution of this paper is to present facts and possible solutions as well as comments on future research needs.&lt;/p&gt;