title: Traffic-related air pollution exposure is associated with allergic sensitization, asthma, and poor lung function in middle age.
abstract: Traffic-related air pollution (TRAP) exposure is associated with allergic airway diseases and reduced lung function in children, but evidence concerning adults, especially in low-pollution settings, is scarce and inconsistent.
  
  
  
  We sought to determine whether exposure to TRAP in middle age is associated with allergic sensitization, current asthma, and reduced lung function in adults, and whether these associations are modified by variants in Glutathione S-Transferase genes.
  
  
  
  The study sample comprised the proband 2002 laboratory study of the Tasmanian Longitudinal Health Study. Mean annual residential nitrogen dioxide (NO2) exposure was estimated for current residential addresses using a validated land-use regression model. Associations between TRAP exposure and allergic sensitization, lung function, current wheeze, and asthma (n = 1405) were investigated using regression models.
  
  
  
  Increased mean annual NO2exposure was associated with increased risk of atopy (adjusted odds ratio [aOR], 1.14; 95% CI, 1.02-1.28 per 1 interquartile range increase in NO2[2.2 ppb]) and current wheeze (aOR, 1.14; 1.02-1.28). Similarly, living less than 200 m from a major road was associated with current wheeze (aOR, 1.38; 95% CI, 1.06-1.80) and atopy (aOR, 1.26; 95% CI, 0.99-1.62), and was also associated with having significantly lower prebronchodilator and postbronchodilator FEV1and prebronchodilator forced expiratory flow at 25% to 75% of forced vital capacity. We found evidence of interactions between living less than 200 m from a major road and GSTT1 polymorphism for atopy, asthma, and atopic asthma. Overall, carriers of the GSTT1 null genotype had an increased risk of asthma and allergic outcomes if exposed to TRAP.
  
  
  
  Even relatively low TRAP exposures confer an increased risk of adverse respiratory and allergic outcomes in genetically susceptible individuals.
authors.affiliation: Allergy and Lung Health Unit, Centre for Epidemiology and Biostatistics, School of Population & Global Health, the University of Melbourne, Melbourne, Australia.
authors.forename: Gayan
authors.initials: G
authors.lastname: Bowatte
authors.affiliation: Allergy and Lung Health Unit, Centre for Epidemiology and Biostatistics, School of Population & Global Health, the University of Melbourne, Melbourne, Australia.
authors.forename: Caroline J
authors.initials: CJ
authors.lastname: Lodge
authors.affiliation: School of Public Health, the University of Queensland, Brisbane, Australia.
authors.forename: Luke D
authors.initials: LD
authors.lastname: Knibbs
authors.affiliation: Allergy and Lung Health Unit, Centre for Epidemiology and Biostatistics, School of Population & Global Health, the University of Melbourne, Melbourne, Australia.
authors.forename: Adrian J
authors.initials: AJ
authors.lastname: Lowe
authors.affiliation: School of Psychology & Public Health, Department of Public Health, La Trobe University, Melbourne, Australia.
authors.forename: Bircan
authors.initials: B
authors.lastname: Erbas
authors.affiliation: School of Public Health & Preventive Medicine, Monash University, Melbourne, Australia.
authors.forename: Martine
authors.initials: M
authors.lastname: Dennekamp
authors.affiliation: Woolcock Institute of Medical Research, The University of Sydney, Sydney, Australia; South Western Sydney Clinical School, University of New South Wales, Sydney, Australia.
authors.forename: Guy B
authors.initials: GB
authors.lastname: Marks
authors.affiliation: Cancer Epidemiology Centre, the Cancer Council Victoria, Melbourne, Australia.
authors.forename: Graham
authors.initials: G
authors.lastname: Giles
authors.affiliation: Royal Brisbane Hospital, Brisbane, Australia.
authors.forename: Stephen
authors.initials: S
authors.lastname: Morrison
authors.affiliation: Alfred Hospital, Melbourne, Australia.
authors.forename: Bruce
authors.initials: B
authors.lastname: Thompson
authors.affiliation: Inflammation and Infection Research Centre, Faculty of Medicine, University of New South Wales, Sydney, Australia.
authors.forename: Paul S
authors.initials: PS
authors.lastname: Thomas
authors.affiliation: Busselton Population Medical Research Institute, Perth, Australia; School of Population Health, the University of Western Australia, Perth, Australia; School of Pathology and Laboratory Medicine, the University of Western Australia, Perth, Australia; PathWest Laboratory Medicine of WA, Sir Charles Gairdner Hospital, Perth, Australia.
authors.forename: Jennie
authors.initials: J
authors.lastname: Hui
authors.affiliation: Allergy and Lung Health Unit, Centre for Epidemiology and Biostatistics, School of Population & Global Health, the University of Melbourne, Melbourne, Australia.
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Perret
authors.affiliation: School of Public Health & Preventive Medicine, Monash University, Melbourne, Australia.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Abramson
authors.affiliation: NHMRC CRE, University of Tasmania Medical School, Hobart, Australia.
authors.forename: Haydn
authors.initials: H
authors.lastname: Walters
authors.affiliation: Allergy and Lung Health Unit, Centre for Epidemiology and Biostatistics, School of Population & Global Health, the University of Melbourne, Melbourne, Australia.
authors.forename: Melanie C
authors.initials: MC
authors.lastname: Matheson
authors.affiliation: Allergy and Lung Health Unit, Centre for Epidemiology and Biostatistics, School of Population & Global Health, the University of Melbourne, Melbourne, Australia; Murdoch Childrens Research Institute, Melbourne, Australia. Electronic address: s.dharmage@unimelb.edu.au.
authors.forename: Shyamali C
authors.initials: SC
authors.lastname: Dharmage
mesh_terms: D000328:Adult; D000393:Air Pollutants / Q000009:adverse effects* / Q000032:analysis; D000397:Air Pollution / Q000009:adverse effects* / Q000032:analysis; D001315:Australia / Q000453:epidemiology; D004781:Environmental Exposure / Q000009:adverse effects / Q000032:analysis; D005260:Female; D020022:Genetic Predisposition to Disease; D005982:Glutathione Transferase / Q000235:genetics*; D006801:Humans; D006967:Hypersensitivity / Q000175:diagnosis / Q000453:epidemiology* / Q000235:genetics / Q000503:physiopathology; D008168:Lung / Q000503:physiopathology; D008297:Male; D009585:Nitrogen Dioxide / Q000009:adverse effects* / Q000032:analysis; D016017:Odds Ratio; D012882:Skin Tests; D013147:Spirometry; D001335:Vehicle Emissions / Q000032:analysis / Q000633:toxicity*
chemical_list: D000393:Air Pollutants; D001335:Vehicle Emissions; C413545:glutathione S-transferase T1; D005982:Glutathione Transferase; D009585:Nitrogen Dioxide
keywords: Air pollution; Glutathione S-Transferase genes; allergic sensitization; asthma; respiratory function