title: Increased mortality from infectious pneumonia after occupational exposure to inorganic dust, metal fumes and chemicals.
abstract: OBJECTIVE
  There are epidemiological studies indicating that exposure to metal fumes is a risk factor for infectious pneumonia. Whether occupational exposure to other agents, such as inorganic dust or chemicals, also increases the risk for infectious pneumonia is not clear. The aim of the present study was to elucidate whether occupational exposure to respiratory pollutants and irritants increases the risk for infectious pneumonia.
  
  
  METHODS
  Prospective cohort study. Setting Swedish male construction workers. Participants 320,143 male construction workers exposed to inorganic dust (asbestos, man-made mineral fibres, dust from cement, concrete and quartz), wood dust, metal fumes and chemicals (organic solvents, diisocyanates and epoxi resins) or unexposed. Main outcome measures The cohort was followed from 1971 to 2003 and the main outcome measures were mortality to infectious pneumonia, lobar pneumonia or pneumococcal pneumonia. RRs were obtained by the person-years method and from Poisson regression models, adjusting for baseline values of age and smoking habits.
  
  
  RESULTS
  Among men aged 20-64 years there was increased mortality from infectious pneumonias among construction workers exposed to metal fumes (RR 2.31, 95% CI 1.35 to 3.95), inorganic dust (RR 1.87, 95% CI 1.22 to 2.87) and chemicals (RR 1.91, 95% CI 1.37 to 3.22). The mortality was also increased from both lobar pneumonia and pneumococcal pneumonia. Among men aged 65-84 years the occupational exposure to inorganic dust and chemicals was associated with slightly increased mortality from infectious pneumonia. Among groups with mutually exclusive exposures there was increased mortality from infectious pneumonias among construction workers exposed to inorganic dust, but not among those exposed to wood dust or chemicals. There were no cases among workers exposed only to metal fumes.
  
  
  CONCLUSIONS
  Our findings indicate that exposure to inorganic dust increases the mortality from infectious pneumonias, especially lobar pneumonia and pneumococcal pneumonia. The mechanism is unclear, but the effect may be mediated through induced airways inflammation.
authors.affiliation: Section of Occupational and Environmental Medicine, Sahlgrenska Academy, University of Gothenburg, Box 414, SE-405 30 Gothenburg, Sweden. kjell.toren@amm.gu.se
authors.forename: Kjell
authors.initials: K
authors.lastname: Torén
authors.forename: Ingemar
authors.initials: I
authors.lastname: Qvarfordt
authors.forename: Ingvar A
authors.initials: IA
authors.lastname: Bergdahl
authors.forename: Bengt
authors.initials: B
authors.lastname: Järvholm
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000395:Air Pollutants, Occupational / Q000633:toxicity; D060389:Construction Industry; D004391:Dust; D004812:Epidemiologic Methods; D015386:Hazardous Substances / Q000633:toxicity*; D006801:Humans; D008297:Male; D008670:Metals / Q000633:toxicity; D008875:Middle Aged; D009784:Occupational Diseases / Q000209:etiology* / Q000401:mortality; D016273:Occupational Exposure / Q000009:adverse effects* / Q000032:analysis; D009894:Opportunistic Infections / Q000209:etiology* / Q000401:mortality; D018410:Pneumonia, Bacterial / Q000209:etiology* / Q000401:mortality; D011018:Pneumonia, Pneumococcal / Q000209:etiology / Q000401:mortality; D013548:Sweden / Q000453:epidemiology; D055815:Young Adult
chemical_list: D000395:Air Pollutants, Occupational; D004391:Dust; D015386:Hazardous Substances; D008670:Metals