title: Distributed lag associations between respiratory illnesses and mortality with suspended particle concentration in Tula, a highly polluted industrial region in Central Mexico.
abstract: OBJECTIVE
  We aimed to evaluate the association between changes in airborne particulate matter concentration (PM) with changes in cases of mortality, acute respiratory infections (ARI) and asthma over 2004-2008 in an industrialized and polluted region in central Mexico.
  
  
  METHODS
  A generalized linear model with a Poisson distribution and a negative binomial analysis was used to evaluate the influence of PM and temperature on all-cause mortality (All-cause-M), cause-specific mortality (Cause-specific-M), ARI and asthma, using cubic spline functions and distributed lags of PM. Estimated changes in relative risk were calculated for an exposure corresponding to each increase of 10 μg/m(3) in PM level.
  
  
  RESULTS
  Associations between PM and mortality and morbidity were statistically most consistent for total suspended particulate (TSP) than for particulate matter <10 μM aerodynamic diameter (PM10). The greatest effects in mortality were observed with a 3-week lag, and effects were greater for Cause-specific-M. We also found a displacement effect up to 4-week lag for Cause-specific-M and TSP. The greatest effects in morbidity were observed at 0-week lag, yet they were statistically marginal and were greater for asthma. We found a displacement effect at 4-5-6-week lag for asthma and TSP. All associations of mortality and morbidity, expressed as change in relative risk, were greater with PM10; however, all of them were statistically marginal.
  
  
  CONCLUSIONS
  Increased respiratory morbidity and mortality is associated with weekly changes of PM air pollution in the region. A reduction in air pollutants from industrial sources would benefit life quality and health of the exposed population.
authors.affiliation: Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, Delegación Gustavo A. Madero, 07760 Mexico, D F, Mexico.
authors.forename: Eva M
authors.initials: EM
authors.lastname: Melgar-Paniagua
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Vega-Rangel
authors.forename: Luz M
authors.initials: LM
authors.lastname: Del Razo
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Lucho-Constantino
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Rothenberg
authors.forename: Andrea
authors.initials: A
authors.lastname: De Vizcaya-Ruiz
mesh_terms: D000397:Air Pollution / Q000009:adverse effects / Q000032:analysis; D001249:Asthma / Q000139:chemically induced* / Q000453:epidemiology / Q000401:mortality*; D004781:Environmental Exposure / Q000009:adverse effects; D004784:Environmental Monitoring; D006801:Humans; D008800:Mexico / Q000453:epidemiology; D052638:Particulate Matter / Q000009:adverse effects*; D015203:Reproducibility of Results; D012141:Respiratory Tract Infections / Q000139:chemically induced* / Q000453:epidemiology / Q000401:mortality*; D013696:Temperature
chemical_list: D052638:Particulate Matter