Relative risks and 95% confidence intervals from multivariate analysis of allergic sensitisation in relation to weighted road density within 75 m radius and 50 m radius of home.

<p>RRs expressed per unit increase in weighted road density variable, where one unit relates to 100's education, mother's education, environmental tobacco smoke exposure, breastfed to 6 months, any dog owned by 8 years, any cat owned by 8 years, maternal smoking in pregnancy, gas cooking at home.</p

Percent difference and 95% confidence intervals from multivariate analysis of lung function and flow variables in relation to weighted road density within 75 m radius and 50 m radius of home.

<p>Percent difference expressed per unit increase in weighted road density variable, where one unit relates to 100</p

(Overall Sample) Univariate and multivariate logistic regression analysis for allergic sensitisation in relation to weighted road density within 50 m radius of home.

<p>Relative Risks (RRs) expressed per unit increase in weighted road density variable, where one unit relates to 100 m local road or 33.3 m of motorway within given radius of the home.</p><p>RR is the Relative Risk per unit increase in weighted road density from Poisson regression with robust standard errors conducted on binary variables.</p>‡<p>Multivariate analyses are adjusted for sex, father's education, mother's education, environmental tobacco smoke exposure, breastfed to 6 months, any dog owned by 8 years, any cat owned by 8 years, maternal smoking in pregnancy, gas cooking at home.</p

(Overall Sample) Univariate and multivariate linear regression for spirometry and total IgE (kU/L) and Poisson regression with robust standard error analyses for AHR, eNO, questionnaire outcomes (all) in relation to weighted road density within 50 m radius of home.

<p>Relative Risks (RRs) and percent difference (B) expressed per unit increase in weighted road density variable, where one unit relates to 100 m local road or 33.3 m of motorway within given radius of the home.</p><p>Lung function variables are logged, therefore percent differences by B = 100(e^β−1) are presented for each unit increase in weighted road density, where β is the regression coefficient from linear regression analyses for continuous variables.</p><p>RR is the Relative Risk per unit increase in weighted road density from Poisson regression with robust standard errors conducted on binary variables.</p>‡<p>Multivariate analyses are adjusted for sex, father's education, mother's education, environmental tobacco smoke exposure, breastfed to 6 months, any dog owned by 8 years, any cat owned by 8 years, maternal smoking in pregnancy, gas cooking at home. Univariate and multivariate lung function analyses included adjustment for age, height and weight.</p>‡‡<p>p-value from additional analysis where an interaction term of weighted road density and atopy was included in the model.</p

Traffic intensity distribution within 75(Figure 1a) and 50 m of home (Figure 1b) for all children with available questionnaire or clinical data, n = 419.

<p>Traffic intensity distribution within 75(<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0098978#pone-0098978-g001" target="_blank">Figure 1a</a>) and 50 m of home (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0098978#pone-0098978-g001" target="_blank">Figure 1b</a>) for all children with available questionnaire or clinical data, n = 419.</p

Respiratory Health before and after the Opening of a Road Traffic Tunnel: A Planned Evaluation

<div><h3>Objective</h3><p>The construction of a new road tunnel in Sydney, Australia, and concomitant reduction in traffic on a major road presented the opportunity to study the effects of this traffic intervention on respiratory health.</p> <h3>Methods</h3><p>We made measurements in a cohort of residents in the year before the tunnel opened (2006) and in each of two years afterwards (2007–2008). Cohort members resided in one of four exposure zones, including a control zone. Each year, a respiratory questionnaire was administered (n = 2,978) and a panel sub-cohort (n = 380) performed spirometry once and recorded peak expiratory flow and symptoms twice daily for nine weeks.</p> <h3>Results</h3><p>There was no consistent evidence of improvement in respiratory health in residents living along the bypassed main road, despite a reduction in traffic from 90,000 to 45,000 vpd. Residents living near tunnel feeder roads reported more upper respiratory symptoms in the survey but not in the panel sub-cohort. Residents living around the tunnel ventilation stack reported more upper and lower respiratory symptoms and had lower spirometric volumes after the tunnel opened. Air pollutant levels measured near the stack did not increase over the study period.</p> <h3>Conclusion</h3><p>The finding of adverse health effects among residents living around the stack is unexpected and difficult to explain, but might be due to unmeasured pollutants or risk factors or an unrecognized pollutant source nearby. The lack of improvement in respiratory health among people living along the bypassed main road probably reflects a minimal change in exposure due to distance of residence from the road.</p> </div

Symptom prevalence of the diary panel sub-cohort, by zone and year (n = 380)^a.

a<p>Each subject contributed up to 63 days of data in the diary study.</p>b<p>Participants in overlapping area of increased exposure zone and stack zone, diary panel cohort (2006 = 6(4); 2007 = 5(2); 2008 = 5(3)), contributed data to both zones. n =  subjects in overlapping area with spirometry; (n) = subjects in overlapping area taking part in peak flow and symptom diary.</p>c<p>Panel sub-cohort participants who took part in peak flow/symptom diary.</p>d<p>Symptoms recorded by diary. % represents proportion of subjects experiencing those symptoms a) at least one day during the study period; b) >10% of days during the study period; c) >20% of days during the study period.</p>e<p>Composite variables derived from variables measured in questionnaire (See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0048921#pone.0048921.s001" target="_blank">Table S1</a>, Supporting Information).</p>f<p>Attributes measured by questionnaire.</p

Lung function measures, and other characteristics of the diary panel sub-cohort, by zone and year (n = 380)^a.

a<p>Each subject contributed up to 63 days of data in the diary panel.</p>b<p>Participants in overlapping area of increased exposure zone and stack zone: diary panel cohort (2006 = 6(4); 2007 = 5(2); 2008 = 5(3)) contributed data to both zones.</p>c<p>Participants with spirometry and eNO.</p>d<p>bd-bronchodilator.</p>e<p>Geometric mean and SD.</p>f<p>Participants with PEF/symptom diary.</p>g<p>PEF recorded three times twice daily at morning and evening. Highest of three measurements used for each session.</p

Map of study area showing the zones, tunnel, ventilation stacks and land use.

<p>Map of study area showing the zones, tunnel, ventilation stacks and land use.</p

Symptom prevalence and other characteristics of the study cohort by zone and year (n = 2978).

a<p>Participants in overlapping area of increased exposure zone and stack zone, entire cohort (2006 = 48; 2007 = 24; 2008 = 15) contributed data to both zones.</p>b<p>Composite variables derived from questionnaire data (see Supporting information, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0048921#pone.0048921.s001" target="_blank">Table S1</a>).</p>c<p>Subjects <18 years assumed to be non-smokers.</p>d<p>Environmental tobacco smoke.</p>e<p>Included Diploma/TAFE, and participants who responded “Other”.</p>f<p>Included participants who refused to respond.</p