title: Lifetime pesticide use and telomere shortening among male pesticide applicators in the Agricultural Health Study.
abstract: BACKGROUND
  Telomere length (TL) in surrogate tissues may be influenced by environmental exposures.
  
  
  OBJECTIVE
  We aimed to determine whether lifetime pesticides use is associated with buccal cell TL.
  
  
  METHODS
  We examined buccal cell TL in relation to lifetime use of 48 pesticides for 1,234 cancer-free white male pesticide applicators in the Agricultural Health Study (AHS), a prospective cohort study of 57,310 licensed pesticide applicators. Participants provided detailed information on lifetime use of 50 pesticides at enrollment (1993-1997). Buccal cells were collected from 1999 to 2006. Relative telomere length (RTL) was measured using quantitative real-time polymerase chain reaction. We used linear regression modeling to evaluate the associations between specific pesticides and the logarithm of RTL, adjusting for age at buccal cell collection, state of residence, applicator license type, chewing tobacco use, and total lifetime days of all pesticide use.
  
  
  RESULTS
  The mean RTL for participants decreased significantly in association with increased lifetime days of pesticide use for alachlor (p = 0.002), 2,4-dichlorophenoxyacetic acid (2,4-D; p = 0.004), metolachlor (p = 0.01), trifluralin (p = 0.05), permethrin (for animal application) (p = 0.02), and toxaphene (p = 0.04). A similar pattern of RTL shortening was observed with the metric lifetime intensity-weighted days of pesticide use. For dichlorodiphenyltrichloroethane (DDT), we observed significant RTL shortening for lifetime intensity-weighted days (p = 0.04), but not for lifetime days of DDT use (p = 0.08). No significant RTL lengthening was observed for any pesticide.
  
  
  CONCLUSIONS
  Seven pesticides previously associated with cancer risk in the epidemiologic literature were inversely associated with RTL in buccal cell DNA among cancer-free pesticide applicators. Replication of these findings is needed because we cannot rule out chance or fully rule out bias.
authors.affiliation: Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA.
authors.forename: Lifang
authors.initials: L
authors.lastname: Hou
authors.forename: Gabriella
authors.initials: G
authors.lastname: Andreotti
authors.forename: Andrea A
authors.initials: AA
authors.lastname: Baccarelli
authors.forename: Sharon
authors.initials: S
authors.lastname: Savage
authors.forename: Jane A
authors.initials: JA
authors.lastname: Hoppin
authors.forename: Dale P
authors.initials: DP
authors.lastname: Sandler
authors.forename: Joseph
authors.initials: J
authors.lastname: Barker
authors.forename: Zhong-Zheng
authors.initials: ZZ
authors.lastname: Zhu
authors.forename: Mirjam
authors.initials: M
authors.lastname: Hoxha
authors.forename: Laura
authors.initials: L
authors.lastname: Dioni
authors.forename: Xiao
authors.initials: X
authors.lastname: Zhang
authors.forename: Stella
authors.initials: S
authors.lastname: Koutros
authors.forename: Laura E Beane
authors.initials: LE
authors.lastname: Freeman
authors.forename: Michael C
authors.initials: MC
authors.lastname: Alavanja
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000383:Agriculture; D003634:DDT / Q000633:toxicity; D006801:Humans; D007484:Iowa; D008297:Male; D008875:Middle Aged; D009061:Mouth Mucosa / Q000737:chemistry / Q000187:drug effects*; D009657:North Carolina; D016273:Occupational Exposure; D010575:Pesticides / Q000633:toxicity*; D011446:Prospective Studies; D060888:Real-Time Polymerase Chain Reaction; D059506:Telomere Shortening / Q000187:drug effects*
chemical_list: D010575:Pesticides; D003634:DDT