title: Associations between ultrafine and fine particles and mortality in five central European cities - Results from the UFIREG study.
abstract: BACKGROUND
  Evidence on health effects of ultrafine particles (UFP) is still limited as they are usually not monitored routinely. The few epidemiological studies on UFP and (cause-specific) mortality so far have reported inconsistent results.
  
  
  OBJECTIVE
  The main objective of the UFIREG project was to investigate the short-term associations between UFP and fine particulate matter (PM)<2.5μm (PM2.5) and daily (cause-specific) mortality in five European Cities. We also examined the effects of PM<10μm (PM10) and coarse particles (PM2.5-10).
  
  
  METHODS
  UFP (20-100nm), PM and meteorological data were measured in Dresden and Augsburg (Germany), Prague (Czech Republic), Ljubljana (Slovenia) and Chernivtsi (Ukraine). Daily counts of natural and cardio-respiratory mortality were collected for all five cities. Depending on data availability, the following study periods were chosen: Augsburg and Dresden 2011-2012, Ljubljana and Prague 2012-2013, Chernivtsi 2013-March 2014. The associations between air pollutants and health outcomes were assessed using confounder-adjusted Poisson regression models examining single (lag 0-lag 5) and cumulative lags (lag 0-1, lag 2-5, and lag 0-5). City-specific estimates were pooled using meta-analyses methods.
  
  
  RESULTS
  Results indicated a delayed and prolonged association between UFP and respiratory mortality (9.9% [95%-confidence interval: -6.3%; 28.8%] increase in association with a 6-day average increase of 2750particles/cm(3) (average interquartile range across all cities)). Cardiovascular mortality increased by 3.0% [-2.7%; 9.1%] and 4.1% [0.4%; 8.0%] in association with a 12.4μg/m(3) and 4.7μg/m(3) increase in the PM2.5- and PM2.5-10-averages of lag 2-5.
  
  
  CONCLUSIONS
  We observed positive but not statistically significant associations between prolonged exposures to UFP and respiratory mortality, which were independent of particle mass exposures. Further multi-centre studies are needed investigating several years to produce more precise estimates on health effects of UFP.
authors.affiliation: Helmholtz Zentrum München-German Research Center for Environmental Health, Institute of Epidemiology II, Neuherberg, Germany. Electronic address: stefanie.lanzinger@helmholtz-muenchen.de.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Lanzinger
authors.affiliation: Helmholtz Zentrum München-German Research Center for Environmental Health, Institute of Epidemiology II, Neuherberg, Germany.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Schneider
authors.affiliation: Helmholtz Zentrum München-German Research Center for Environmental Health, Institute of Epidemiology II, Neuherberg, Germany.
authors.forename: Susanne
authors.initials: S
authors.lastname: Breitner
authors.affiliation: Department of Epidemiology, Lazio Region Health Service, Rome, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Stafoggia
authors.affiliation: National Institute of Public Health Slovenia, Ljubljana, Slovenia.
authors.forename: Ivan
authors.initials: I
authors.lastname: Erzen
authors.affiliation: Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Prague, Czech Republic.
authors.forename: Miroslav
authors.initials: M
authors.lastname: Dostal
authors.affiliation: Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Prague, Czech Republic.
authors.forename: Anna
authors.initials: A
authors.lastname: Pastorkova
authors.affiliation: Saxon State Office for Environment, Agriculture and Geology, Dresden, Germany.
authors.forename: Susanne
authors.initials: S
authors.lastname: Bastian
authors.affiliation: Helmholtz Zentrum München-German Research Center for Environmental Health, Institute of Epidemiology II, Neuherberg, Germany; Environmental Science Center, University of Augsburg, Augsburg, Germany.
authors.forename: Josef
authors.initials: J
authors.lastname: Cyrys
authors.affiliation: Research Association Public Health Saxony and Saxony-Anhalt, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.
authors.forename: Anja
authors.initials: A
authors.lastname: Zscheppang
authors.affiliation: L.I. Medved's Research Center of Preventive Toxicology, Food and Chemical Safety, Ministry of Health, Chernivtsi, Ukraine.
authors.forename: Tetiana
authors.initials: T
authors.lastname: Kolodnitska
authors.affiliation: Helmholtz Zentrum München-German Research Center for Environmental Health, Institute of Epidemiology II, Neuherberg, Germany.
authors.forename: Annette
authors.initials: A
authors.lastname: Peters
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000393:Air Pollutants / Q000009:adverse effects* / Q000032:analysis; D000397:Air Pollution / Q000009:adverse effects*; D002318:Cardiovascular Diseases / Q000401:mortality*; D002423:Cause of Death; D002648:Child; D002675:Child, Preschool; D002947:Cities / Q000453:epidemiology; D005060:Europe / Q000453:epidemiology; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D008962:Models, Theoretical; D010316:Particle Size; D052638:Particulate Matter / Q000009:adverse effects* / Q000032:analysis; D012120:Respiration Disorders / Q000401:mortality*; D055815:Young Adult
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter
keywords: Central Europe; Mortality; Particulate matter; Time series; Ultrafine particles