title: The association between air pollution and blood pressure in traffic controllers in Santo André, São Paulo, Brazil.
abstract: BACKGROUND
  Urban air pollutants are associated with cardiovascular events. Traffic controllers are at high risk for pollution exposure during outdoor work shifts.
  
  
  OBJECTIVE
  The purpose of this study was to evaluate the relationship between air pollution and systemic blood pressure in traffic controllers during their work shifts.
  
  
  METHODS
  This cross-sectional study enrolled 19 male traffic controllers from Santo André city (São Paulo, Brazil) who were 30-60 years old and exposed to ambient air during outdoor work shifts. Systolic and diastolic blood pressure readings were measured every 15 min by an Ambulatory Arterial Blood Pressure Monitoring device. Hourly measurements (lags of 0-5h) and the moving averages (2-5h) of particulate matter (PM(10)), ozone (O(3)) ambient concentrations and the acquired daily minimum temperature and humidity means from the São Paulo State Environmental Agency were correlated with both systolic and diastolic blood pressures. Statistical methods included descriptive analysis and linear mixed effect models adjusted for temperature, humidity, work periods and time of day.
  
  
  RESULTS
  Interquartile increases of PM(10) (33 μg/m(3)) and O(3) (49 μg/m(3)) levels were associated with increases in all arterial pressure parameters, ranging from 1.06 to 2.53 mmHg. PM(10) concentration was associated with early effects (lag 0), mainly on systolic blood pressure. However, O(3) was weakly associated most consistently with diastolic blood pressure and with late cumulative effects.
  
  
  CONCLUSIONS
  Santo André traffic controllers presented higher blood pressure readings while working their outdoor shifts during periods of exposure to ambient pollutant fluctuations. However, PM(10) and O(3) induced cardiovascular effects demonstrated different time courses and end-point behaviors and probably acted through different mechanisms.
authors.affiliation: Environmental Epidemiology Study Group, Laboratory of Experimental Air Pollution, University of São Paulo Faculty of Medical Sciences, São Paulo, Brazil.
authors.forename: Paulo
authors.initials: P
authors.lastname: Sérgio Chiarelli
authors.forename: Luiz Alberto
authors.initials: LA
authors.lastname: Amador Pereira
authors.forename: Paulo Hilário do
authors.initials: PH
authors.lastname: Nascimento Saldiva
authors.forename: Celso
authors.initials: C
authors.lastname: Ferreira Filho
authors.forename: Maria Lúcia
authors.initials: ML
authors.lastname: Bueno Garcia
authors.forename: Alfésio Luís
authors.initials: AL
authors.lastname: Ferreira Braga
authors.forename: Lourdes
authors.initials: L
authors.lastname: Conceição Martins
mesh_terms: D000328:Adult; D000395:Air Pollutants, Occupational / Q000032:analysis* / Q000633:toxicity; D000397:Air Pollution / Q000706:statistics & numerical data*; D001336:Automobiles / Q000706:statistics & numerical data*; D001794:Blood Pressure / Q000187:drug effects; D001938:Brazil / Q000453:epidemiology; D003430:Cross-Sectional Studies; D006801:Humans; D006973:Hypertension / Q000139:chemically induced / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure / Q000032:analysis / Q000706:statistics & numerical data; D010126:Ozone / Q000032:analysis; D052638:Particulate Matter / Q000032:analysis / Q000633:toxicity; D001335:Vehicle Emissions / Q000032:analysis* / Q000633:toxicity
chemical_list: D000395:Air Pollutants, Occupational; D052638:Particulate Matter; D001335:Vehicle Emissions; D010126:Ozone