title: Use of hair colouring products and risk of multiple myeloma among US women.
abstract: OBJECTIVE
  To evaluate the association between personal hair dye use and risk of multiple myeloma among women.
  
  
  METHODS
  A population-based case-control study of 175 cases of multiple myeloma and 679 controls. Cases and controls were interviewed regarding the type and colour of hair colouring product used, age at first use, age use stopped, duration, and the frequency of use per year. Odds ratios (ORs) and 95% confidence intervals (CI) were estimated using unconditional logistic regression to compare never users with four exposure groups: all users, ever semi-permanent dye users, ever permanent dye users and dark permanent dye users (most frequent use).
  
  
  RESULTS
  No association was found between ever reporting hair colouring product use and myeloma risk among all users (OR 0.8; 95% CI 0.5 to 1.1), semi-permanent dye users (OR 0.7; 95% CI 0.4 to 1.2), permanent dye users (OR 0.8; 95% CI 0.5 to 1.1) or dark permanent dye users (OR 0.8; 95% CI 0.5 to 1.3). There were no significant associations among women who used hair dyes before 30 years of age, started use before 1980, had >or=240 lifetime applications, or had used dark permanent dye for 28 or more years.
  
  
  CONCLUSIONS
  No evidence of an association between hair colouring product use and myeloma risk was found. However, given the conflicting body of literature on hair colouring product use and risk of multiple myeloma, this question should be further evaluated in larger studies or consortia, and in high risk groups.
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, DHHS, 6120 Executive Blvd, EPS 8122, Bethesda, MD 20852, USA. Koutross@mail.nih.gov
authors.forename: S
authors.initials: S
authors.lastname: Koutros
authors.forename: D
authors.initials: D
authors.lastname: Baris
authors.forename: E
authors.initials: E
authors.lastname: Bell
authors.forename: T
authors.initials: T
authors.lastname: Zheng
authors.forename: Y
authors.initials: Y
authors.lastname: Zhang
authors.forename: T R
authors.initials: TR
authors.lastname: Holford
authors.forename: B P
authors.initials: BP
authors.lastname: Leaderer
authors.forename: O
authors.initials: O
authors.lastname: Landgren
authors.forename: S Hoar
authors.initials: SH
authors.lastname: Zahm
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D003237:Connecticut / Q000453:epidemiology; D005260:Female; D006202:Hair Dyes / Q000009:adverse effects*; D006801:Humans; D008875:Middle Aged; D009101:Multiple Myeloma / Q000139:chemically induced* / Q000453:epidemiology; D018570:Risk Assessment; D055815:Young Adult
chemical_list: D006202:Hair Dyes