Personal use of hair dye and cancer risk in a prospective cohort of Chinese women.
Although widely studied over the past 40 years, personal use of hair dye generally has not been associated with overall cancer risk. The association between hair dye use and risk of bladder and hematopoietic cancers has been less conclusive. Most hair dye studies have been case-control studies conducted in Caucasian populations. We examined the relationship between personal hair dye use and cancer risk in a prospective cohort of 70,366 Chinese women. After an average of 7 years of follow up, 2437 women were newly diagnosed with cancer by 31 December 2005. Cox proportional hazard models were used to estimate relative risks (RR) and 95% confidence intervals (CI) of cancer risk associated with hair dye use, adjusting for potential confounding factors. Compared with women who reported no hair dye use, ever users had an overall cancer risk of 0.89 (95% CI 0.82, 0.97). No significant association was observed for several common cancers, including cancers of the breast (RR 0.93, 95% CI 0.78, 1.09), lung (RR 0.81, 95% CI 0.62, 1.09), stomach (RR 0.90, 95% CI 0.66, 1.21), and colorectum (RR 1.04, 95% CI 0.84, 1.28). We also found no significant association with most other cancers, including bladder cancer (RR 1.14, 95% CI 0.56, 2.35) and hematopoietic cancers overall (RR 0.89, 95% CI 0.59, 1.35) or their subtypes, including non-Hodgkin lymphoma, multiple myeloma, and leukemia. We generally found no evidence of an association between personal use of hair dye and cancer risk, although our study is limited by small numbers for certain cancer types.
Mendelsohn
Julie Bloch
JB
Division of Cancer Epidemiology and Genetics, National Cancer Institute (NCI), National Institutes of Health, Bethesda, MD, USA. mendelju@mail.nih.gov
Li
Qi-Zhai
QZ
Ji
Bu-Tian
BT
Shu
Xiao-Ou
XO
Yang
Gong
G
Li
Hong-Lan
HL
Lee
Kyoung-Mu
KM
Yu
Kai
K
Rothman
Nathaniel
N
Gao
Yu-Tang
YT
Zheng
Wei
W
Chow
Wong-Ho
WH
D001943:Breast Neoplasms / Q000453:epidemiology; D002681:China; D015331:Cohort Studies; D015179:Colorectal Neoplasms / Q000453:epidemiology; D005260:Female; D006202:Hair Dyes / Q000009:adverse effects*; D006801:Humans; D008175:Lung Neoplasms / Q000453:epidemiology; D009369:Neoplasms / Q000453:epidemiology*; D016016:Proportional Hazards Models; D011446:Prospective Studies; D013274:Stomach Neoplasms / Q000453:epidemiology; D001749:Urinary Bladder Neoplasms / Q000453:epidemiology
D006202:Hair Dyes