title: Asthma diagnosed after 11 September 2001 among rescue and recovery workers: findings from the World Trade Center Health Registry.
abstract: BACKGROUND
  Studies have consistently documented declines in respiratory health after 11 September 2001 (9/11) among surviving first responders and other World Trade Center (WTC) rescue, recovery, and clean-up workers.
  
  
  OBJECTIVE
  The goal of this study was to describe the risk of newly diagnosed asthma among WTC site workers and volunteers and to characterize its association with WTC site exposures.
  
  
  METHODS
  We analyzed 2003-2004 interview data from the World Trade Center Health Registry for workers who did not have asthma before 9/11 (n = 25,748), estimating the risk of newly diagnosed asthma and its associations with WTC work history, including mask or respirator use.
  
  
  RESULTS
  Newly diagnosed asthma was reported by 926 workers (3.6%). Earlier arrival and longer duration of work were significant risk factors, with independent dose responses (p < 0.001), as were exposure to the dust cloud and pile work. Among workers who arrived on 11 September, longer delays in the initial use of masks or respirators were associated with increased risk of asthma; adjusted odds ratios ranged from 1.63 [95% confidence interval (CI), 1.03-2.56) for 1 day of delay to 3.44 (95% CI, 1.43-8.25) for 16-40 weeks delay.
  
  
  CONCLUSIONS
  The rate of self-reported newly diagnosed asthma was high in the study population and significantly associated with increased exposure to the WTC disaster site. Although we could not distinguish appropriate respiratory protection from inappropriate, we observed a moderate protective effect of mask or respirator use. The findings underscore the need for adequate and timely distribution of appropriate protective equipment and the enforcement of its use when other methods of controlling respiratory exposures are not feasible.
authors.affiliation: New York City Department of Health and Mental Hygiene, New York, New York 10013, USA.
authors.forename: Katherine
authors.initials: K
authors.lastname: Wheeler
authors.forename: Wendy
authors.initials: W
authors.lastname: McKelvey
authors.forename: Lorna
authors.initials: L
authors.lastname: Thorpe
authors.forename: Megan
authors.initials: M
authors.lastname: Perrin
authors.forename: James
authors.initials: J
authors.lastname: Cone
authors.forename: Daniel
authors.initials: D
authors.lastname: Kass
authors.forename: Mark
authors.initials: M
authors.lastname: Farfel
authors.forename: Pauline
authors.initials: P
authors.lastname: Thomas
authors.forename: Robert
authors.initials: R
authors.lastname: Brackbill
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001249:Asthma / Q000175:diagnosis / Q000453:epidemiology*; D004391:Dust; D005260:Female; D006801:Humans; D008297:Male; D008397:Masks / Q000706:statistics & numerical data; D008875:Middle Aged; D009519:New York City; D012042:Registries; D018635:Rescue Work; D012134:Respiratory Protective Devices / Q000706:statistics & numerical data; D047851:September 11 Terrorist Attacks
chemical_list: D004391:Dust