title: The Drake Health Registry Study: cause-specific mortality experience of workers potentially exposed to beta-naphthylamine.
abstract: OBJECTIVE
  To examine the cause-specific mortality experience of an occupational cohort with probable past exposure to beta-naphythylamine (BNA).
  
  
  METHODS
  Subjects were 374 male and 26 female workers employed at a Pennsylvania chemical plant that produced or used beta-naphthylamine (BNA) between 1940 and 1981. Vital status through 1998 was determined for 97.5% of the cohort and cause of death for 100% of 79 deaths. Limited industrial hygiene data and reports from former employees were used to categorize workers as high, medium, or low risk for BNA exposure. Statistical analyses included US and local county-based standardized mortality ratios (SMRs).
  
  
  RESULTS
  We observed statistically significantly elevated county rate-based SMRs for all causes combined (SMR = 1.98, 95% confidence interval (CI) = 1.56-2.49), all malignant neoplasms combined (28 deaths, SMR = 3.08, 95% CI = 2.05-4.46), respiratory system cancer (12 deaths, SMR = 3.91, 95% CI = 2.02-6.83), and bladder cancer (four deaths, SMR = 16.83, 95% CI = 4.59-43.1). Three bladder cancer cases were classified as high risk (SMR = 26.79, 95% CI = 5.53-78.29). Mortality risks were also elevated for most other malignant and non-malignant cause of death categories examined.
  
  
  CONCLUSIONS
  Bladder cancer risk remains highly elevated among Drake/Kilsdonk workers and appears to be causally related to past BNA exposure. While lifestyle and behavioral risk factors may explain some of the mortality excesses for non-urological cancers, the possibility remains that BNA exposure may have also played a role in these and other observed cancer excesses.
authors.affiliation: Department of Biostatistics, A-414 Crabtree Hall, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA 15261, USA. lcs3@pitt.edu
authors.forename: Laura D
authors.initials: LD
authors.lastname: Cassidy
authors.forename: Ada O
authors.initials: AO
authors.lastname: Youk
authors.forename: Gary M
authors.initials: GM
authors.lastname: Marsh
mesh_terms: D015081:2-Naphthylamine / Q000506:poisoning*; D000328:Adult; D002273:Carcinogens; D002423:Cause of Death; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D016273:Occupational Exposure; D010414:Pennsylvania; D012042:Registries; D012307:Risk Factors; D001749:Urinary Bladder Neoplasms / Q000139:chemically induced / Q000401:mortality
chemical_list: D002273:Carcinogens; D015081:2-Naphthylamine