Ambient Concentrations Of Nitrogen Dioxide Research Articles

Air pollution and the sequelae of COVID-19 patients: A multistate analysis

ImportanceRecent evidence links air pollution to the severity COVID-19 symptoms and to death from the disease. To date, however, few studies have assessed whether air pollution affects the sequelae to more severe states or recovery from COVID-19 in a cohort with individual data. ObjectiveTo assess how air pollution affects the transition to more severe COVID-19 states or to recovery from COVID-19 infection in a cohort with detailed patient information. Design and OutcomesWe used a cohort design that followed patients admitted to hospital in the Kaiser Permanente Southern California (KPSC) Health System, which has 4.7 million members with characteristics similar to the general population. Enrollment began on 06/01/2020 and ran until 01/30/2021 for all patients admitted to hospital while ill with COVID-19. All possible states of sequelae were considered, including deterioration to intensive care, to death, discharge to recovery, or discharge to death. Transition risks were estimated with a multistate model. We assessed exposure using chemical transport model that predicted ambient concentrations of nitrogen dioxide, ozone, and fine particulate matter (PM2.5) at a 1 km scale. ResultsEach increase in PM2.5 concentration equivalent to the interquartile range was associated with increased risk of deterioration to intensive care (HR of 1.16; 95% CI: 1.12–1.20) and deterioration to death (HR of 1.11; 95% CI: 1.04–1.17). Results for ozone were consistent with PM2.5 effects, but ozone also affected the transition from recovery to death: HR of 1.24 (95% CI: 1.01–1.51). NO2 had weaker effects but displayed some elevated risks. ConclusionsPM2.5 and ozone were significantly associated with transitions to more severe states while in hospital and to death after discharge from hospital. Reducing air pollution could therefore lead to improved prognosis for COVID-19 patients and a sustainable means of reducing the health impacts of coronaviruses now and in the future.

Disparities in ambient nitrogen dioxide pollution in the United States

Average ambient concentrations of nitrogen dioxide (NO2), an important air pollutant, have declined in the United States since the enactment of the Clean Air Act. Despite evidence that NO2 disproportionately affects racial/ethnic minority groups, it remains unclear what drives the exposure disparities and how they have changed over time. Here, we provide evidence by integrating high-resolution (1 km × 1 km) ground-level NO2 estimates, sociodemographic information, and source-specific emission intensity and location for 217,740 block groups across the contiguous United States from 2000 to 2016. We show that racial/ethnic minorities are disproportionately exposed to higher levels of NO2 pollution compared with Whites across the United States and within major metropolitan areas. These inequities persisted over time and have worsened in many cases, despite a significant decrease in the national average NO2 concentration over the 17-y study period. Overall, traffic contributes the largest fraction of NO2 disparity. Contributions of other emission sources to exposure disparities vary by location. Our analyses offer insights into policies aimed at reducing air pollution exposure disparities among races/ethnicities and locations.

Biosolar green roofs and ambient air pollution in city centres: Mixed results

Green roofs are known for their ability to reduce ambient air pollution. While the accurate valuation of the air pollution removal services provided by green roofs is rapidly developing, much of this research is still in its infancy, with only a small number of in-situ studies that truly examine the impact of green roofs on city air quality. In this study we present the longest study conducted on an Australian green roof with in-situ air quality monitoring. Field measurements were utilised to calculate the ambient air pollutant removal of an extensive green roof compared to a proximal, near-identical conventional roof over three seasons. The average concentrations of ambient ozone was lower on the green roof compared to that of the conventional roof surface. The theoretical ozone and nitrogen dioxide removal rates on the green roof were higher than the average concentrations calculated from previous research at 3.82 g m-2y-1 and 1.29 g m-2y-1 respectively. There was no significant difference in the average suspended particulate matter concentrations between the two roofs. The particulate matter removal rate was lower than the average previous findings at 0.29 g m-2y-1. The green roof studied was theoretically capable of removing 0.5 kg of PM2.5, 6.9 kg of O3 and 2.3 kg of NO2 per year, values which were significantly higher than the conventional roof. Ambient nitrogen dioxide concentrations were higher on the green roof – largely attributed to local construction activities.

Health Risk Assessment of Ambient Nitrogen Dioxide Concentrations in Urban and Industrial Area in Rayong Province, Thailand

Nitrogen dioxide (NO2) is a hazardous gas and an air pollutant that is released from a variety of sources, including fossil fuel mining and burning, automobile emissions and other sources. The inhalation of NO2 has been linked to the exact causes of a variety of health issues, including respiratory disorders and a variety of other maladies. The largest source of NO2 exposure is through traffic density emissions. The concentrations of ambient NO2 in Rayong province’s urban, industrial and background areas were measured during rainy, winter and summer seasons. Samples of NO2 were collected with the use of passive samplers during September 2017 to April 2018. The result of the analysis revealed that NO2 concentration of urban area, industrial area and background area were 13.9 - 43.0, 10.4 - 34.0 and 5.8 - 35.2 µg/m3, respectively. It is to be noted that NO2 concentrations in urban and industrial areas were significantly higher than those in background areas (p < 0.05). The dominant source is located nearby high traffic density and industrial establishments. However, the NO2 values obtained from seasonal variations were not significantly different (p > 0.05). A weak correlation was observed between NO2 concentrations and total precipitation (r = −0.237). The low wind speed has no effect on NO2 dispersion. As a result of the geographical and seasonal variation of NO2 concentrations, it was determined that local activities such as traffic density had a much greater impact on NO2 levels than meteorological factors. The hazard quotient (HQ) values from NO2 exposure in Rayong province were less than 1, indicating that the risk was negligible. The inhalation of NO2 by residents who live near the roadside and highway, on the other hand, may endanger their health.
 HIGHLIGHTS
 
 NO2 concentrations in Rayong province related to traffic density and industrial establishments
 The ambient NO2 levels in urban and industrial areas were approximately 1.4 times higher than those in background areas (p < 0.05)
 Residents of Rayong province who live near the roadside and highway road may put their health at risk due to NO2 inhalation
 
 GRAPHICAL ABSTRACT

The association between postpartum depression and air pollution during pregnancy and postpartum period: a national population study in Taiwan

Epidemiological evidence shows the association between air pollutants and several mental health outcomes, including depression, sleep disturbance, dementia, childhood neurodevelopment and suicide. Pregnant women are believed to be more susceptible and vulnerable to environmental pollutants, and postpartum depression (PPD) is a prevalent debilitating mental disorder. However, data on the effects of exposure to air pollution during pregnancy and postpartum period on the risk of PPD remain limited. This study aimed to evaluate the association between exposure to ambient air pollution during pregnancy and postpartum period and the incidence of PPD. The Taiwan Birth Cohort Study recruited representative 12% of all newborn in 2005 and their mothers by two-stage stratified sampling, including 21 248 mother–infant pairs. The occurrence of PPD was assessed by a self-reported questionnaire. Exposure to air pollutants during pregnancy and postpartum period was estimated using hybrid kriging/land-use regression (LUR) and integrated LUR-machine learning model based on data from the air monitoring stations. Logistic regression was then conducted to determine adjusted odds ratios (aORs) of PPD in relation to air pollutants. A total of 21 188 women were included in the final analysis, among whom 3,648 (17.2%) developed PPD within 6 months postpartum. The occurrence of PPD was significantly related to exposure to ambient concentrations of nitrogen dioxide (NO2) during first trimester after adjustment [aOR: 1.081 per interquartile range (10.67 ppb), 95% confidence interval: 1.003, 1.165], but not to particulate matter ⩽2.5 µm in diameter or carbon monoxide. Exposure to ambient NO2 during early pregnancy was significantly related to the occurrence of PPD among the women investigated in this population-based study.

Breast cancer risk in relation to ambient concentrations of nitrogen dioxide and particulate matter: results of a population-based case-control study corrected for potential selection bias (the CECILE study)

BackgroundThere is only scant evidence that air pollution increases the risk of breast cancer. ObjectivesWe investigated this relationship for three air pollutants: nitrogen dioxide (NO2) and particulate matter with an aerodynamical diameter below 10 µm (PM10) and 2.5 µm (PM2.5). MethodsWe conducted a population-based case-control study on breast cancer in two French départements, including 1,229 women diagnosed with breast cancer in 2005–2007 and 1,316 control women frequency-matched on age. Concentrations of NO2, PM10 and PM2.5 at participants’ addresses occupied during the last 10 years were assessed using a chemistry transport model. Odds ratios (OR) and 95% confidence intervals (95% CI) were estimated using multivariable logistic regression models where each woman was assigned a weight depending on her probability of selection into the study. ResultsThe OR for breast cancer per 10-µg/m3 increase in NO2 was 1.11 (95% CI, 0.98, 1.26), and 1.41 (95% CI 1.07, 1.86) in the highest exposure quintile (Q5), compared to the first. The ORs per 10-µg/m3 NO2 did not markedly differ between pre- (OR 1.09, 95% CI 0.89, 1.35)) and post-menopausal women (OR 1.14, 95% CI 0.97, 1.33)), but the OR was substantially higher for hormone-receptor positive (ER+/PR+) breast tumor subtypes (OR 1.15, 95% CI 1.00, 1.31) than for ER–/PR– tumors (OR 0.95, 95% CI 0.72, 1.26). Breast cancer risk was not associated with either PM10 (OR per 1 µg/m3 1.01, 95% CI, 0.96, 1.06) or PM2.5 (OR per 1 µg/m3 1.02, 95% CI 0.95, 1.08), regardless of the menopausal status or of the breast tumor subtype. DiscussionOur study provides evidence that NO2 exposure, a marker of traffic-related air pollutants, may be associated with an increased risk of breast cancer, particularly ER+/PR+ tumors.

A hybrid approach to predict daily NO2 concentrations at city block scale

Estimating the ambient concentration of nitrogen dioxide (NO2) is challenging because NO2 generated by local fossil fuel combustion varies greatly in concentration across space and time. This study demonstrates an integrated hybrid approach combining dispersion modeling and land use regression (LUR) to predict daily NO2 concentrations at a high spatial resolution (e.g., 50 m) in the New York tri-state area. The daily concentration of traffic-related NO2 was estimated at the Environmental Protection Agency's NO2 monitoring sites in the study area for the years 2015–2017, using the Research LINE source (R-LINE) model with inputs of traffic data provided by the Highway Performance and Management System and meteorological data provided by the NOAA Integrated Surface Database. We used the R-LINE-predicted daily concentrations of NO2 to build mixed-effects regression models, including additional variables representing land use features, geographic characteristics, weather, and other predictors. The mixed model was selected by the Elastic Net method. Each model's performance was evaluated using the out-of-sample coefficient of determination (R2) and the square root of mean squared error (RMSE) from ten-fold cross-validation (CV). The mixed model showed a good prediction performance (CV R2: 0.75–0.79, RMSE: 3.9–4.0 ppb). R-LINE outputs improved the overall, spatial, and temporal CV R2 by 10.0%, 18.9% and 7.7% respectively. Given the output of R-LINE is point-based and has a flexible spatial resolution, this hybrid approach allows prediction of daily NO2 at an extremely high spatial resolution such as city blocks.

HAVE VEHICLE REGISTRATION RESTRICTIONS IMPROVED URBAN AIR QUALITY IN JAPAN?

About 2.6 million noncompliant vehicles were removed from designated metropolitan areas in Japan after the introduction of vehicle registration restrictions under the 1992 Automobile NOx Control Law. Based on a difference‐in‐differences framework and using a monitor‐level panel dataset for the period January 1981–December 2015, we find that the intervention led to a 3%–6% reduction in the monthly mean ambient concentration of nitrogen dioxide (NO2) in the treated areas. Back‐of‐the‐envelope calculations identify benefits equal to about US$104 million as a result of reduced mortality from asthma. (JEL Q53, Q58)

Associations between incident breast cancer and ambient concentrations of nitrogen dioxide from a national land use regression model in the Canadian National Breast Screening Study

BackgroundAir pollution has been classified as a human carcinogen based largely on epidemiological studies of lung cancer. Recent research suggests that exposure to ambient air pollution increases the risk of female breast cancer especially in premenopausal women. MethodsOur objective was to determine the association between residential exposure to ambient nitrogen dioxide (NO2) and newly diagnosed cases of invasive breast cancer in a cohort of 89,247 women enrolled in the Canadian National Breast Screening Study between 1980 and 1985. Vital status and incident breast cancers through 2005 were determined through record linkage to the Canadian national mortality and cancer registries. Estimates of exposures to NO2 using participants’ addresses at time of entry into the study were derived from a national land use regression model. We classified women as reaching menopause according to information obtained at baseline. In addition, as we had no information from women on their menopausal status during the observation period, we conducted analyses using different cut-points for defining postmenopausal status (i.e., at 50 or at 52 years of age), and hence we had four non-independent cohorts. We computed rate ratios for the incidence of breast cancer and their 95% confidence intervals (CI) separately for premenopausal and postmenopausal women. Our Cox models used attained age as the time axis and the rate ratios were adjusted for several individual-level risk factors, including reproductive history, as well as census-based neighborhood-level characteristics. ResultsThe median concentration of NO2 was about 15 parts per billion (ppb). After adjusting for personal risk factors and contextual variables, we found no evidence of associations for the incidence of breast cancer in the postmenopausal cohorts. In premenopausal women, the rate ratio for an increase of 9.7 ppb (about the interquartile range) was 1.13 (95%CI: 0.94–1.37) for the 50 years of age cut-off for menopausal status and it was 1.17 (95%CI: 1.00–1.38) for the 52 years of age cut-off. ConclusionsOur findings suggest that exposure to low concentrations of NO2, a marker for traffic-related air pollution, increases the risk of premenopausal breast cancer, but not postmenopausal breast cancer.

Relationships between airborne pollutants, serum albumin adducts and short-term health outcomes in an experimental crossover study

Exposure to air pollution can have both short-term and long-term effects on health. However, the relationships between specific pollutants and their effects can be obscured by characteristics of both the pollution and the exposed population. One way of elucidating the relationships is to link exposures and internal changes at the level of the individual. To this end, we combined personal exposure monitoring (59 individuals, Oxford Street II crossover study) with mass-spectrometry-based analyses of putative serum albumin adducts (fixed-step selected reaction monitoring). We attempted to infer adducts’ identities using data from another, higher-resolution mass spectrometry method, and were able to detect a semi-synthetic standard with both methods. A generalised least squares regression method was used to test for associations between amounts of adducts and pollution measures (ambient concentrations of nitrogen dioxide and particulate matter), and between amounts of adducts and short-term health outcomes (measures of lung health and arterial stiffness). Amounts of some putative adducts (e.g., one with a positive mass shift of ∼143 Da) were associated with exposure to pollution (11 associations), and amounts of other adducts were associated with health outcomes (eight associations). Adducts did not appear to provide a link between exposures and short-term health outcomes.

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Prediction of Ambient Nitrogen Dioxide Concentrations in the Vicinity of Industrial Complex Area, Thailand

The AERMOD dispersion model was evaluated for its performance in predicting 1-hour average nitrogen dioxide (NO2) concentrations in the vicinity of the largest petrochemical industrial complex in Thailand during the period between January 2012 and December 2013. Measured data from 10 ambient air monitoring stations were intensively used to compare with modeled results. Model results indicated that the tier 1 approach (full conversion of NOx to NO2) provided the most accurate results compared with other tiers. It also performed very well in predicting the extreme end of NO2 concentrations. With an absence of emission data from mobile sources, tier 1 was concluded as the most appropriate scheme for prediction of ambient NO2 ground-level concentrations in this study.

An integrative approach for determination of air pollution and its health effects in a coal fired power plant area by passive sampling

Ambient concentrations of nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone (O3) and volatile organic compounds (VOCs) were measured at several locations in Kütahya, a severely polluted city and also characterized as a thermal power plant city, in Turkey. Two-week extensive passive sampling campaigns were carried out in summer and winter at 108 sampling sites that were classified into three main groups as urban, rural and industrial. Spatial and seasonal distributions of the measured pollutants were evaluated employing Geographical Information System techniques. All pollutant concentrations showed an increasing pattern in winter, except for ozone. The concentrations of VOCs were substantially higher particularly at sampling sites with high traffic and population densities. Power plants were noted as important sources for VOCs since high concentrations were measured especially around the power plants. Highest NO2 levels were observed in the city center while there was a general decrease in the concentration levels far away from the city center. Considerably higher SO2 levels were observed in the settlements where local coal is used for residential heating. Seasonal variations in SO2 concentrations were quite low around the thermal power plants indicating their important effect on atmospheric levels. A basic population exposure assessment was conducted for two largest settlements of the province (Kütahya city center and Tavşanlı) by combining population density maps with pollutant distribution maps of NO2 and SO2. Exposure to NO2 and SO2 were assessed separately according to a classification made for different degrees of exposure. Cancer risks associated with inhalation of benzene were also estimated. Higher risk values were obtained from the sampling sites with higher population densities, especially in winter. Risk values estimated for 95 sampling sites were higher than EPA's acceptable risk value (1 × 10−6).

Effects of ambient nitrogen dioxide concentrations on adverse birth outcomes in urban and rural areas of Alberta, Canada.

Introduction: The incidence of low birth weight (LBW), preterm birth (PB) and small for gestational age (SGA) in Alberta has been greater than the national average in the last decade, raising a public health concern. Understanding the effects (individual and interactions) of maternal, social and environmental risk factors on adverse birth outcomes (ABOs) is currently a subject of active research. We present the effects of nitrogen dioxide (NO2) emissions in the ambient air on the incidence of LBW, PB, and SGA by considering maternal risk factors and socioeconomic status, for both urban and rural areas in Alberta. Methods: We analyzed all singletons live births with 22-42 weeks of gestational age (n=334,894) in Alberta (2006-2012), and 24 maternal risk factors (e.g. diabetes). We used available postal code data for NO2 levels and socioeconomic status. We classified the mothers’ residential postal code as urban/rural. We applied multivariate logistic regression for estimating the effect (Odds ratios) of NO2 levels on LBW, spontaneous PB (categorized as 22-26 weeks; 27-28 weeks; 29-33 weeks, and 34-36 weeks), and SGA (categorized as <3rd, 3rd to 5th, and 5th to 10th percentiles), in urban and rural areas. Odds ratios were adjusted for significant maternal risk factors and socioeconomic status. Results: We detected significant (OR 95%CIs > 1) effects of ambient air NO2 with LBW in rural (OR=1.10), and urban areas (OR=1.01); PB in urban areas [27-28 weeks (OR = 1.04), 29-33 weeks (OR = 1.02), and 34-36 weeks (OR = 1.01)]; SGA in rural [3rd and 5th percentiles (OR=1.06 and OR=1.07, respectively)], and in urban areas for all percentiles [3rd and 5th (OR=1.01), 10th (OR=1.02)]. Currently, we are assessing the contribution of other industrial emissions on ABOs. Conclusions: Ambient air nitrogen dioxide levels were associated with increased risk of adverse birth outcomes between 1% and 7%, mainly impacting PB (27-28 weeks) in urban areas, and LBW and SGA in rural areas.

Ambient nitrogen dioxide and sulfur dioxide concentrations over a region of natural gas production, Northeastern British Columbia, Canada

The Peace River district of Northeastern British Columbia, Canada is a region of natural gas production that has undergone rapid expansion since 2005. In order to assess air quality implications, Willems badge passive diffusive samplers were deployed for six two-week exposure periods between August and November 2013, at 24 sites across the region to assess the ambient concentration of nitrogen dioxide (NO2) and sulfur dioxide (SO2). The highest concentrations of both species (NO2: 9.1 ppb, SO2: 1.91 ppb) during the whole study period (except the 1st exposure period), were observed in Taylor (Site 14), which is consistent with its location near major industrial sources. Emissions from industrial activities, and their interaction with meteorology and topography, result in variations in atmospheric dispersion that can increase air pollution concentrations in Taylor. However, relatively high concentrations of NO2 were also observed near the center of Chetwynd (site F20), indicating the importance of urban emissions sources in the region as well. Observations of both species from the other study sites document the spatial variability and show relatively high concentrations near Fort St. John and Dawson Creek, where unconventional oil and gas development activities are quite high. Although a few sites in Northeastern British Columbia recorded elevated concentrations of NO2 and SO2 during this investigation, the concentrations over the three-month period were well below provincial annual ambient air quality objectives. Nonetheless, given the limited observations in the region, and the accelerated importance of unconventional oil and gas extraction in meeting energy demands, it is imperative that monitoring networks are established to further assess the potential for elevated ambient concentrations associated with industrial emissions sources in the Peace River region.

Aggregated GPS tracking of vehicles and its use as a proxy of traffic-related air pollution emissions

Most air quality models use traffic-related variables as an input. Previous studies estimated nearby vehicular activity through sporadic traffic counts or via traffic assignment models. Both methods have previously produced poor or no data for nights, weekends and holidays. Emerging technologies allow the estimation of traffic through passive monitoring of location-aware devices. Examples of such devices are GPS transceivers installed in vehicles. In this work, we studied traffic volumes that were derived from such data. Additionally, we used these data for estimating ambient nitrogen dioxide concentrations, using a non-linear optimisation model that includes basic dispersion properties. The GPS-derived data show great potential for use as a proxy for pollutant emissions from motor-vehicles.

Spatiotemporal calibration and resolution refinement of output from deterministic models.

Spatiotemporal calibration of output from deterministic models is an increasingly popular tool to more accurately and efficiently estimate the true distribution of spatial and temporal processes. Current calibration techniques have focused on a single source of data on observed measurements of the process of interest that are both temporally and spatially dense. Additionally, these methods often calibrate deterministic models available in grid-cell format with pixel sizes small enough that the centroid of the pixel closely approximates the measurement for other points within the pixel. We develop a modeling strategy that allows us to simultaneously incorporate information from two sources of data on observed measurements of the process (that differ in their spatial and temporal resolutions) to calibrate estimates from a deterministic model available on a regular grid. This method not only improves estimates of the pollutant at the grid centroids but also refines the spatial resolution of the grid data. The modeling strategy is illustrated by calibrating and spatially refining daily estimates of ambient nitrogen dioxide concentration over Connecticut for 1994 from the Community Multiscale Air Quality model (temporally dense grid-cell estimates on a large pixel size) using observations from an epidemiologic study (spatially dense and temporally sparse) and Environmental Protection Agency monitoring stations (temporally dense and spatially sparse). Copyright © 2016 John Wiley & Sons, Ltd.

Have vehicle emissions of primary NO2 peaked?

Reducing ambient concentrations of nitrogen dioxide (NO2) remains a key challenge across many European urban areas, particularly close to roads. This challenge mostly relates to the lack of reduction in emissions of oxides of nitrogen (NOx) from diesel road vehicles relative to the reductions expected through increasingly stringent vehicle emissions legislation. However, a key component of near-road concentrations of NO2 derives from directly emitted (primary) NO2 from diesel vehicles. It is well-established that the proportion of NO2 (i.e. the NO2/NOx ratio) in vehicle exhaust has increased over the past decade as a result of vehicle after-treatment technologies that oxidise carbon monoxide and hydrocarbons and generate NO2 to aid the emissions control of diesel particulate. In this work we bring together an analysis of ambient NOx and NO2 measurements with comprehensive vehicle emission remote sensing data obtained in London to better understand recent trends in the NO2/NOx ratio from road vehicles. We show that there is evidence that NO2 concentrations have decreased since around 2010 despite less evidence of a reduction in total NOx. The decrease is shown to be driven by relatively large reductions in the amount of NO2 directly emitted by vehicles; from around 25 vol% in 2010 to 15 vol% in 2014 in inner London, for example. The analysis of NOx and NO2 vehicle emission remote sensing data shows that these reductions have been mostly driven by reduced NO2/NOx emission ratios from heavy duty vehicles and buses rather than light duty vehicles. However, there is also evidence from the analysis of Euro 4 and 5 diesel passenger cars that as vehicles age the NO2/NOx ratio decreases. For example the NO2/NOx ratio decreased from 29.5 ± 2.0% in Euro 5 diesel cars up to one year old to 22.7 ± 2.5% for four-year old vehicles. At some roadside locations the reductions in primary NO2 have had a large effect on reducing both the annual mean and number of hourly exceedances of the European Limit Values of NO2.

Ambient air pollution and adverse birth outcomes: a natural experiment study.

BackgroundRadical regulations to improve air quality, including traffic control, were implemented prior to and during the 2008 Beijing Olympic Games. Consequently, ambient concentrations of nitrogen dioxide (NO2) and particular matter 10 micrometers or less (PM10), were reduced in a distinct and short window of time, which presented a natural experiment for testing the relationships between maternal exposure to PM10 and NO2 during pregnancy and adverse birth outcomes.MethodsWe estimated the effect of PM10 and NO2 exposure during each trimester of gestation on the risk of preterm birth among live births and the birth weight among term babies. The data were based on 50,874 live births delivered between January 1, 2006 and December 31, 2010 at the Beijing Haidian Maternal and Child Health Hospital. Air monitoring data for the same period were obtained from the Beijing Municipal Environmental Monitoring Center.ResultsAmong full-term births, maternal exposure to NO2 in the third trimester predicted birth weight, with each 10-unit increment (per 10 ug/m3) in NO2 concentration associated with a 13.78 g (95 % confidence interval: −21.12, −6.43; p < 0.0001) reduction in birth weight. This association was maintained after adjusting for other pollutants, including carbon monoxide (CO), sulfur dioxide (SO2), and PM10. No relationship was found between the concentration of PM10 and low birth weight among full-term births. Neither PM10 nor NO2 concentrations predicted the risk of premature birth.ConclusionsExposure to ambient air pollution during certain periods of pregnancy may decrease birth weight, but the effect size is small.

A land use regression model for ambient nitrogen dioxide concentration nearby a commercial airport for low-cost flights (Rome-Ciampino)

Background: Several studies suggest that airport emissions could worse air quality in theneighbourhoods. Aims: To evaluate the spatial variability of nitrogen dioxide (NO2) concentrations in relati...