Outdoor Nitrogen Dioxide Research Articles

Roles of pollution in the prevalence and exacerbations of allergic diseases in Asia

The prevalence of asthma and allergic diseases has been found to be increasingly rapidly, especially in developing countries. Environmental factors have been found to be important contributors to the manifestations of allergic diseases. Air pollution has been extensively studied in different regions of the world. The levels of ambient air pollutants in many Asian countries are very high when compared with those in developed Western countries. However, the prevalence of asthma was relatively low across many Asian countries. Many studies have clearly documented that environmental air pollution is an important factor resulting in exacerbations of asthma. In particular, levels of traffic-related pollutants are increasing rapidly across many Asian countries in parallel with the level of urbanization and economic development. The loss of protective factors associated with a rural environment will further contribute to the adverse effect on patients with allergic diseases such as asthma. In this review the roles of air pollution were examined in relation to the inception and exacerbations of allergic diseases in Asia.

Outdoor Air Pollution and Incidence of Ischemic and Hemorrhagic Stroke

Evidence linking outdoor air pollution and incidence of stroke is limited. We examined effects of outdoor air pollution on the incidence of ischemic and hemorrhagic stroke at the population level focusing on middle-aged and older people. We used a small-area level ecological study design and a stroke register set up to capture all incident cases of first-ever stroke occurring in a defined geographical area in south London (948 census output areas) where road traffic contributes to spatial variation in air pollution. Population-weighted averages were calculated for output areas using outdoor nitrogen dioxide and PM(10) concentrations modeled at a 20-m resolution. There were 1832 ischemic and 348 hemorrhagic strokes in 1995 to 2004 occurring among a resident population of 267 839. Mean (SD) concentration was 25.1 (1.2) μg/m(3) (range, 23.3-36.4 μg/m(3)) for PM(10) and 41.4 (3.0) μg/m(3) (range, 35.4-68.0 μg/m(3)) for nitrogen dioxide. For ischemic stroke, adjusted rate ratios per 10-μg/m(3) increase, for all ages, 40 to 64 and 65 to 79 years, respectively, were 1.22 (0.77-1.93), 1.12 (0.55-2.28), and 1.86 (1.10-3.13) for PM(10) and 1.11 (0.93-1.32), 1.13 (0.86-1.50), and 1.23 (0.99-1.53) for nitrogen dioxide. For hemorrhagic stroke, the corresponding rate ratios were 0.52 (0.20-1.37), 0.78 (0.17-3.51), and 0.51 (0.12-2.22) for PM(10) and 0.86 (0.60-1.24), 1.12 (0.66-1.90), and 0.78 (0.44-1.39) for nitrogen dioxide. Although there was no significant association between outdoor air pollutants and ischemic stroke incidence for all ages combined, there was a suggestion of increased risk among people aged 65 to 79 years. There was no evidence of increased incidence in hemorrhagic stroke.

Respiratory health symptoms among students exposed to different levels of air pollution in a Turkish city.

In this study, we aimed to investigate the frequency of respiratory health symptoms among high school students attending schools at industrial, urban and rural areas in a Turkish city. Three schools located in different zones of the city having different pollution characteristics were chosen based on the pollutant distribution maps using Geographical Information Systems (GIS) software. A cross-sectional survey was performed among 667 high school students in the schools. Outdoor and indoor nitrogen dioxide (NO2) and ozone (O3) concentrations were also measured by passive samplers in the same schools to investigate possible routes of exposure. Chronic pulmonary disease (OR = 1.49; 95%CI: 1.11–1.99; p = 0.008), tightness in the chest (OR = 1.57; 95%CI: 1.22–2.02; p = 0.001), morning cough (OR = 1.81 95%CI: 1.19–2.75; p = 0.006) were higher among students in the industrial zone where nitrogen dioxide and ozone levels were also highest. There were no indoor sources of nitrogen dioxide and ozone exists in the schools except for the dining hall. As a conclusion, this study has noticed that air pollution and respiratory health problems among high school students are high in industrial zones and the use of passive samplers combined with GIS is an effective tool that may be used by public health researchers to identify pollutant zones and persons at risk.

Outdoor air pollution and respiratory health in patients with COPD

ObjectivesTime series studies have shown adverse effects of outdoor air pollution on mortality and hospital admissions in patients with chronic obstructive pulmonary disease (COPD) but panel studies have been inconsistent....

Stability of measured and modelled spatial contrasts in NO2 over time

ObjectivesLand use regression (LUR) modelling is a popular method to estimate outdoor air pollution concentrations at the home and/or work addresses of individual subjects in epidemiological studies. Typically, such models...

Contribution of Outdoor Nitrogen Dioxide on Indoor Air Quality in Roadside Commercial Shops

Contribution of Outdoor Nitrogen Dioxide on Indoor Air Quality in Roadside Commercial Shops

Preterm birth and exposure to air pollutants during pregnancy

Background Research has shown that prenatal exposure to air pollutants may have a detrimental effect on fetal development, with the strength of the relationship depending on the effect being studied. The evidence to date, however, is insufficient to establish a direct causal link between such exposure and preterm delivery. This study evaluates the specific effect of prenatal exposure to NO 2 and benzene on preterm births. Methods The population under study comprised 785 pregnant women who formed part of the INMA cohort in Valencia, Spain (2003–2005). Multiple regression models were used for mapping outdoor nitrogen dioxide (NO 2) and benzene levels throughout the area. Individual exposure was assigned as the estimated outdoor levels at each woman’s home measured during each trimester as well as throughout the entire pregnancy. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated in order to assess the association between preterm birth and exposure to NO 2 and benzene. The shape of the exposure–response curve between air pollution and the risk of preterm birth was analyzed with a flexible approach, introducing a natural cubic spline for air pollution levels into the model. Results Pregnant women exposed to NO 2 and benzene have an increased risk of preterm birth. This risk was shown to be significant when women were exposed to NO 2 levels >46.2 μg/m 3 during the second and third trimesters as well as throughout the entire pregnancy and to benzene levels >2.7 μg/m 3 throughout the entire pregnancy. Conclusion These results suggest that maternal exposure to traffic-related air pollution is associated with preterm birth.

Participant-based monitoring of indoor and outdoor nitrogen dioxide, volatile organic compounds, and polycyclic aromatic hydrocarbons among MICA-Air households

The Mechanistic Indicators of Childhood Asthma (MICA) study in Detroit, Michigan introduced a participant-based approach to reduce the resource burden associated with collection of indoor and outdoor residential air sampling data. A subset of participants designated as MICA-Air conducted indoor and outdoor residential sampling of nitrogen dioxide (NO 2), volatile organic compounds (VOCs), and polycyclic aromatic hydrocarbons (PAHs). This participant-based methodology was subsequently adapted for use in the Vanguard phase of the U.S. National Children’s Study. The current paper examines residential indoor and outdoor concentrations of these pollutant species among health study participants in Detroit, Michigan. Pollutants measured under MICA-Air agreed well with other studies and continuous monitoring data collected in Detroit. For example, NO 2 and BTEX concentrations reported for other Detroit area monitoring were generally within 10–15% of indoor and outdoor concentrations measured in MICA-Air households. Outdoor NO 2 concentrations were typically higher than indoor NO 2 concentration among MICA-Air homes, with a median indoor/outdoor (I/O) ratio of 0.6 in homes that were not impacted by environmental tobacco smoke (ETS) during air sampling. Indoor concentrations generally exceeded outdoor concentrations for VOC and PAH species measured among non-ETS homes in the study. I/O ratios for BTEX species (benzene, toluene, ethylbenzene, and m/p- and o-xylene) ranged from 1.2 for benzene to 3.1 for toluene. Outdoor NO 2 concentrations were approximately 4.5 ppb higher on weekdays versus weekends. As expected, I/O ratios pollutants were generally higher for homes impacted by ETS. These findings suggest that participant-based air sampling can provide a cost-effective alternative to technician-based approaches for assessing indoor and outdoor residential air pollution in community health studies. We also introduced a technique for estimating daily concentrations at each home by weighting 2- and 7-day integrated concentrations using continuous measurements from regulatory monitoring sites. This approach may be applied to estimate short-term daily or hourly pollutant concentrations in future health studies.

Stability of chromogenic colour prints in polluted indoor environments

Chromogenic colour prints are known to be sensitive to storage environments. However, limited research is available on the effect of atmospheric pollutants on these materials, especially pollutants generated indoors. The stability of photographic dyes is of particular interest and the rate of their change can be best described using the standard RGB colour model. Therefore, the colourimetric method was compared to dye extraction and liquid chromatographic analysis to justify its use as a rapid, non-destructive method for quantitative assessment of the rate of change in dye content of colour photographs during degradation. The effects of typical indoor (acetic acid, formaldehyde) and outdoor (nitrogen dioxide) generated pollutants on chromogenic colour prints were then investigated at 80 °C, 60% RH. It was identified that acetic acid leads to the most pronounced changes in photographic dye concentrations, which is significant considering that acetic acid is often the most prominent pollutant in archival environments. On the other hand, formaldehyde exhibited a slight protective effect in comparison to the blank experiment.

Concentrations and determinants of outdoor, indoor and personal nitrogen dioxide in pregnant women from two Spanish birth cohorts

Determinants of outdoor, indoor and personal concentrations of nitrogen dioxide (NO 2) were assessed in a subset of pregnant women of the Spanish INMA (Environment and Childhood) Study. Home indoor and outdoor NO 2 concentrations were measured during 48 h with passive samplers for 50 and 58 women from the INMA cohorts of Valencia and Sabadell, respectively. Women from Sabadell also carried personal NO 2 samplers during the same period. Data on time–activity patterns, socio-economic characteristics, and environmental exposures were obtained through questionnaires. Multiple linear regression models were developed to predict NO 2 levels. In Valencia, median outdoor NO 2 levels (42 µg/m 3) were higher than median indoor levels (36 µg/m 3). In Sabadell, personal NO 2 showed the highest median levels (40 µg/m 3), followed by indoor (32 µg/m 3) and outdoor (29 µg/m 3) levels. Personal exposure to NO 2 correlated best with the indoor NO 2 levels. Temporal and traffic-related variables were significant predictors for outdoor NO 2 levels. Thirty-two percent of the indoor NO 2 variability in the two cohorts was explained by outdoor NO 2 levels and the use of the gas appliances. The model for personal exposure accounted for 59% of the variance in NO 2 levels in Sabadell with four predictor variables (outdoor and indoor NO 2 levels, time spent in outdoor environments and time exposed to a gas cooker). No significant association was found between personal or indoor NO 2 levels and exposure to environmental tobacco smoke (ETS) at home. Personal NO 2 levels were found to be strongly influenced by indoor NO 2 concentrations. The study supports the use of time–activity patterns along with indoor measurements to predict personal exposure to traffic-related air pollution.

Effect of traffic pollution on respiratory and allergic disease in adults: cross-sectional and longitudinal analyses

BackgroundEpidemiological research into the role of traffic pollution on chronic respiratory and allergic disease has focused primarily on children. Studies in adults, in particular those based on objective outcomes such as bronchial hyperresponsiveness, skin sensitisation, and lung function, are limited.MethodsWe have used an existing cohort of 2644 adults aged 18–70 living in Nottingham, UK, for whom baseline health and demographic data were collected in 1991 and computed two markers of exposure to traffic: distance between the home and nearest main road and modelled outdoor nitrogen dioxide (NO2) concentration at the home location. Using multiple regression techniques, we analysed cross-sectional associations with bronchial hyperresponsiveness, FEV1, spirometry-defined COPD, skin test positivity, total IgE and questionnaire-reported wheeze, asthma, eczema and hayfever in 2599 subjects, and longitudinal associations with decline in FEV1 in 1329 subjects followed-up nine years later in 2000.ResultsThere were no significant cross-sectional associations between home proximity to the roadside or NO2 level on any of the outcomes studied (adjusted OR of bronchial hyperresponsiveness in relation to living ≤150 m vs >150 m from a road = 0.92, 95% CI 0.68 to 1.24). Furthermore, neither exposure was associated with a significantly greater decline in FEV1 over time (adjusted mean difference in ΔFEV1 for living ≤150 m vs >150 m of a road = 10.03 ml, 95% CI, -33.98 to 54.04).ConclusionThis study found no evidence to suggest that living in close proximity to traffic is a major determinant of asthma, allergic disease or COPD in adults.

Chronic Exposure to Outdoor Air Pollution and Markers of Systemic Inflammation

Cohort studies suggest that long-term exposure to higher levels of outdoor air pollution increases risk of developing cardiovascular disease. One suggested mechanism is that air pollution, especially particulate matter, induces systemic inflammation, thereby increasing the risk of developing long-term pathologic changes in the cardiovascular system, We aimed to examine the association between long-term exposure to higher levels of air pollution and chronic systemic inflammation. We examined the relationship between 2 markers of systemic inflammation (fibrinogen and C-reactive protein) and measures of outdoor air pollution estimated for each postcode sector of residence, using models incorporating information on pollutant emissions from multiple sources, and atmospheric dispersion and processing, in 3 representative cross-sectional studies of the English population in 1994, 1998, and 2003. These included about 25,000 adults with fibrinogen measurements and 17,000 adults with C-reactive protein measurements. We used multilevel linear regression modeling and pooled the results from the 3 surveys using meta-analysis. We found no associations between concentrations of fibrinogen or C-reactive protein and measures of outdoor air pollution (particulate matter <10 mum in diameter (PM10), nitrogen dioxide, sulfur dioxide, and ozone). Specifically, we found, for each 1-microg/m(3) [corrected] increase in PM(10) concentration, a change in fibrinogen concentrations of -0.08% (95% confidence interval = -0.25 to [corrected] 0.10) and in C-reactive protein concentrations of 0.14% (-1.00 to [corrected] 1.30). Our findings do not support the hypothesis that the association between outdoor air pollution exposure and later cardiovascular disease is mediated by chronic systemic inflammation.

Indoor Air Distribution of Nitrogen Dioxide and Ozone in Urban Hospitals

Indoor air pollution has recently become a public concern in Taiwan. People recognize that indoor air quality (IAQ) may be more important than outdoor air quality because they spend over 80% of their time indoors. IAQ could affect health and comfort of building occupants. The objectives of this study are (1) to characterize the indoor concentrations of selected air pollutants at two hospitals in Hsinchu, Taiwan, (2) to evaluate the potential indoor sources of pollutants in these selected hospitals and their indoor/outdoor relationships, and (3) to compare pollutant concentrations with values published in other studies. A significant between-hospital difference in average indoor concentration of nitrogen dioxide and 54.14, 32.69 ppb for Hospital A and B, respectively (p < 0.05). Indoor nitrogen dioxide concentration was significantly positively correlated with outdoor nitrogen dioxide concentration, PM(10) concentration, and traffic flow (r = 0.91, 0.65 and 0.72, respectively). The ozone level was also lower in our hospitals than 30 ppb standard.

Home Outdoor NO2 and New Onset of Self-Reported Asthma in Adults

Few studies have investigated new onset of asthma in adults in relation to air pollution. The aim of this study is to investigate the association between modeled background levels of traffic-related air pollution at the subjects' home addresses and self-reported asthma incidence in a European adult population. Adults from the European Respiratory Health Survey were included (n = 4185 from 17 cities). Subjects' home addresses were geocoded and linked to outdoor nitrogen dioxide (NO2) estimates, as a marker of local traffic-related pollution. We obtained this information from the 1-km background NO2 surface modeled in APMoSPHERE (Air Pollution Modelling for Support to Policy on Health and Environmental Risk in Europe). Asthma incidence was defined as reporting asthma in the follow-up (1999 to 2001) but not in the baseline (1991 to 1993). A positive association was found between NO2 and asthma incidence (odds ratio 1.43; 95% confidence interval = 1.02 to 2.01) per 10 microg/m. Results were homogeneous among centers (P value for heterogeneity = 0.59). We found an association between a marker of traffic-related air pollution and asthma incidence in European adults.

Associations Between Measures of Socioeconomic Position and Chronic Nitrogen Dioxide Exposure in Worcester, Massachusetts

Census block-group-specific predicted outdoor nitrogen dioxide (NO2; a marker of traffic pollution) levels and four census block group socioeconomic position (SEP) measures were used to evaluate whether chronic exposures to traffic-related air pollutants are higher in areas with lower SEP, after controlling for spatial autocorrelation in mixed models. NO2 levels were predicted using a geographic information system (GIS)-based spatiotemporal model that was validated with measured NO2 concentrations. The GIS-based model predicted weekly NO2 concentrations with high accuracy (slope of 0.98 from regression of held-out observations on predictions) and precision (cross-validation mean absolute error of 2.2 ppb). The model performed well in both rural and urban areas and warm and cold seasons. Estimated mean block group NO2 concentrations were significantly negatively associated with median household income, and positively associated with poverty, crowding, and low educational attainment rates after controlling for spatial autocorrelation. Results indicated that a standard deviation (3.5 ppb) increase in block group NO2 concentrations was associated with a $9090 decrease in median household income. Results suggest that on average those with lower SEP experience higher chronic exposure to outdoor NO2.

Use of GIS Tools for Assessing Residential Exposure to Outdoor Nitrogen Dioxide

P-649 Introduction: INMA-Valencia is a prospective cohort study included in the INMA network seeking to evauate the impat of environment and diet on foetal and early chilhood health. One of its aims is to asses exposure to outdoor nitrogen dioxide (NO2) for the 800 women followed during their pregnancy. Here we present the results mapping the NO2 levels over the study area. Methods: Our cohort is spread out over a great area covering a wide variety of environmental conditions. As part of sampling design, the area was divided in 4 zones, clearly different regarding to population and industrialization criteria: urban (U), metropolitan (M), sub-urban (SU) and rural (R). Each of U, M and S-U areas were grided with a fixed distance beween knots (0.5, 1, 3 km respectively). In the rural zone, one knot in each town center was placed as all of our women in R are living within the towns. 93 sites integrated the entire grid. Outdoor concentrations of NO2 were monitored during 7 days by passive samplers once a trimester (April, June and November 2004 and February 2005), intended to capture seasonal patterns. In each survey, NO2 data from the grid were interpolated using Universal Kriging with a linear drift. Maps were plotted using ArcView 3.2. Home addresses of women were geocoded using public Geopraphic Information Systems. We used cross-validation to compare kriging estimates with the value of the nearby sampler of the grid, and the inverse distance weighted average of neighobour samplers. Results: Median outdoor NO2 kriging estimates were: 40.5 (P10-P90: 23.5, 48.9), 27.9 (16.1, 35.3), 50.2 (33.1, 67.9), 42.5 (19.26, 48.16) μg/m3 in April, June, November and February surveys, respectively. By zone were: 47.2 (P10-P90: 32.5, 57.8), 44.6 (28.9, 59.3), 24.3 (16.7, 37.6) and 14.9 (8.9, 21.1) μg/m3 in U, M, S-U and R, respectively. Cross-validation showed prediction errors for kriging interpolation about of 35.8% of the range in true concentrations, for the neighobour samplers average were about 38.6% and for the nearby sampler about 44%. These results are consistent along sampling surveys. These results are not consistent by zone: In the rural area, nearby samplers provided the best estimates in all surveys. Graphs showed the impact of one motorway crossing the entire area. Discussion and Conclusions: Outdoor NO2 varied spatially within the area of study. We were able to assign levels of NO2 exposure to the women of our cohort: Kriging estimates were used except in the rural area, where the sampler sited in the same town was used. This is a first layer of exposure to be weigthed for covariates controlling the effect of nearby sources. This project was funded by G03/176; ISCIII-FEDER, FIS-FEDER: 03/1615, PI041509.

Gas cooking and reduced lung function in school children

Rationale Outdoor nitrogen dioxide (NO 2) is associated with reduced respiratory health. This could be due to a unique biological effect of this gaseous pollutant or because it serves as a surrogate of fine particles from incineration sources. Cooking with gas in small kitchens produces high concentrations of gaseous irritants (mainly nitrogen dioxide), but not fine particles. Objectives To study the relative impact of cooking with gas on lung function parameters in a cross sectional study of school children. Methods Nearly all elementary school children (2898 children aged 6–10 years) living in the city of Linz (capital of Upper Austria) underwent lung function testing. In a questionnaire administered simultaneously to their parents, information on household conditions including cooking and tobacco smoke exposure was collected. Impact of cooking with gas on lung function controlling for various confounders was analyzed using loglinear multiple regression. Results Gas cooking reduced lung function parameters ranging from 1.1% (not significant) for MEF 25 up to 3.4% ( p = 0.01 ) for peak expiratory flow (PEF). Conclusions Gas stoves can have an adverse impact on children's respiratory health. Parents and caretakers should be advised to insure good ventilation while and after cooking, especially in small and poorly ventilated rooms. This study adds to the growing evidence that gaseous pollutants from incineration sources affect respiratory health directly.

Vehicle exhaust exposure in an incident case-control study of adult asthma

The objective of this case-control study was to evaluate whether traffic-related air pollution exposure at home increases the risk of asthma in adults and to compare two commonly used exposure variables and differences between urban and rural living. Incident cases of asthma and matched controls of subjects aged 20-60 yrs were recruited in Luleå, Sweden. In total 203 cases and 203 controls were enrolled in the study. Exposure was estimated by traffic flow and measured levels of outdoor nitrogen dioxide (NO2) in the surrounding environment of each home, respectively. The relationship between measured levels of NO2 and traffic flow was studied using linear regression. The results indicated a nonsignificant tendency between living in a home close to a high traffic flow and an increased risk of asthma. The association between asthma and measured NO2 was weak and not significant, but the skin-prick test result acted as an effect modifier with a borderline significant association among positives. The correlation between traffic flow and outdoor NO2 was low. The results suggest that living close to high traffic flows might increase the asthma incidence in adults, while the tendency for nitrogen dioxide was only seen among atopics. Traffic flow and nitrogen dioxide had a lower than expected correlation.

Childhood Asthma and Exposure to Traffic and Nitrogen Dioxide

Evidence for a causal relationship between traffic-related air pollution and asthma has not been consistent across studies, and comparisons among studies have been difficult because of the use of different indicators of exposure. We examined the association between traffic-related pollution and childhood asthma in 208 children from 10 southern California communities using multiple indicators of exposure. Study subjects were randomly selected from participants in the Children's Health Study. Outdoor nitrogen dioxide (NO2) was measured in summer and winter outside the home of each child. We also determined residential distance to the nearest freeway, traffic volumes on roadways within 150 meters, and model-based estimates of pollution from nearby roadways. Lifetime history of doctor-diagnosed asthma was associated with outdoor NO2; the odds ratio (OR) was 1.83 (95% confidence interval=1.04-3.22) per increase of 1 interquartile range (IQR=5.7 ppb) in exposure. We also observed increased asthma associated with closer residential distance to a freeway (1.89 per IQR; 1.19-3.02) and with model-based estimates of outdoor pollution from a freeway (2.22 per IQR; 1.36-3.63). These 2 indicators of freeway exposure and measured NO2 concentrations were also associated with wheezing and use of asthma medication. Asthma was not associated with traffic volumes on roadways within 150 meters of homes or with model-based estimates of pollution from nonfreeway roads. These results indicate that respiratory health in children is adversely affected by local exposures to outdoor NO2 or other freeway-related pollutants.

수동식 시료채취기를 이응한 사무실 직장인의 산화질소 노출평가 및 예측 -한국의 서울과 호주의 브리스베인 비교 연구-

Indoor and outdoor nitrogen dioxide (NO<TEX>$_2$</TEX>) concentrations were measured and compared with measurements of personal exposures of 95 persons in Seoul, Korea and 57 persons in Brisbane, Australia, respectively. Time activity diary was used to determine the impact on NO<TEX>$_2$</TEX> exposure assessment and microenvironmental model to estimate the personal NO<TEX>$_2$</TEX> exposure. Most people both Seoul and Brisbane spent their times more than 90% of indoor and more than 50% in home, respectively. Personal NO<TEX>$_2$</TEX> exposures were significantly associated with indoor NO<TEX>$_2$</TEX> levels with Pearson coefficient of 0.70 (p＜0.01) and outdoor NO<TEX>$_2$</TEX> levels with Pearson coefficient of 0.66 (p＜0.01) in Seoul and of 0.51 (p＜0.01) and of 0.33 (p＜0.05) in Brisbane, respectively. Using microenvironmental model by time weighted average model, personal NO<TEX>$_2$</TEX> exposures were estimated with NO<TEX>$_2$</TEX> measurements in indoor home, indoor office and outdoor home. Estimated NO<TEX>$_2$</TEX> measurements were significantly correlated with measured personal exposures (r = 0.69, p＜0.001) in Seoul and in Brisbane (r = 0.66, p＜0.001), respectively. Difference between measured and estimated NO<TEX>$_2$</TEX> exposures by multiple regression analysis was explained that NO<TEX>$_2$</TEX> levels in near workplace and other outdoors in Seoul (p = 0.023), and in transportation in Brisbane (p = 0.019) affected the personal NO<TEX>$_2$</TEX> exposures.