title: Occupational risk factors for nasopharyngeal carcinoma in Hong Kong Chinese: a case-referent study.
abstract: OBJECTIVE
  This study aimed to investigate the occupational risk factors for nasopharyngeal carcinoma (NPC) in Hong Kong Chinese.
  
  
  METHODS
  We conducted a case-referent study with 352 incident cases and 410 referents recruited between June 2010 and December 2012. Full occupational histories were obtained via face-to-face interviews. Unconditional logistic regressions were performed to estimate the odds ratios (ORs) for NPC associated with occupational risk factors.
  
  
  RESULTS
  Workers of craft related trades and elementary occupations were at elevated NPC risk with the adjusted ORs of 2.09 [95% confidence interval (CI) 1.09, 4.01] and 2.14 (95% CI 1.04, 4.41), respectively, compared with those clerical support workers as the reference group. Occupational exposures to cotton dust, chemical fumes, and welding fumes were significantly associated with increased NPC risk after adjustment for confounders [adjusted ORs (95% CIs) 1.93 (1.13, 3.28), 13.11 (1.53, 112.17), and 9.18 (1.05, 80.35), respectively]. We also observed significant exposure-response relationship for the duration of exposure to cotton dust (P for trend = 0.0175). Those with occupational exposure to cotton dust for 15 years or more were at significantly increased risk of NPC (adjusted OR 2.08, 95% CI 1.01, 4.28).
  
  
  CONCLUSIONS
  This study indicates that employment in craft related trades and elementary occupations, as well as occupational exposures to chemical fumes, welding fumes, and cotton dust may be associated with an increased risk of NPC. Further epidemiological studies remain warranted to clarify the roles of specific occupational risk factors on NPC development.
authors.affiliation: The Jockey Club School of Public Health and Primary Care, The Chinese University of Hong Kong, 4/F, School of Public Health Building, Prince of Wales Hospital, Shatin, New Territories, Hong Kong Special Administrative Region, China.|Upper Gastrointestinal Surgery, Department of Molecular Medicine and Surgery, Karolinska Insititutet, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Shao-Hua
authors.initials: SH
authors.lastname: Xie
authors.affiliation: The Jockey Club School of Public Health and Primary Care, The Chinese University of Hong Kong, 4/F, School of Public Health Building, Prince of Wales Hospital, Shatin, New Territories, Hong Kong Special Administrative Region, China. iyu@cuhk.edu.hk.
authors.forename: Ignatius Tak-Sun
authors.initials: IT
authors.lastname: Yu
authors.affiliation: The Jockey Club School of Public Health and Primary Care, The Chinese University of Hong Kong, 4/F, School of Public Health Building, Prince of Wales Hospital, Shatin, New Territories, Hong Kong Special Administrative Region, China.
authors.forename: Lap Ah
authors.initials: LA
authors.lastname: Tse
authors.affiliation: Department of Clinical Oncology, Queen Elizabeth Hospital, Hong Kong Special Administrative Region, China.
authors.forename: Joseph Siu Kie
authors.initials: JSK
authors.lastname: Au
authors.affiliation: Department of Medicine, Queen Elizabeth Hospital, Hong Kong Special Administrative Region, China.
authors.forename: June Sze Man
authors.initials: JSM
authors.lastname: Lau
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D004391:Dust; D005260:Female; D006723:Hong Kong / Q000453:epidemiology; D006801:Humans; D007407:Interviews as Topic; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000453:epidemiology* / Q000209:etiology*; D009784:Occupational Diseases / Q000453:epidemiology* / Q000209:etiology*; D016273:Occupational Exposure / Q000009:adverse effects*; D009790:Occupations; D012307:Risk Factors
chemical_list: D004391:Dust
keywords: Epidemiology; Nasopharyngeal carcinoma; Occupational exposures; Risk factor