title: Associations between arsenic species in exfoliated urothelial cells and prevalence of diabetes among residents of Chihuahua, Mexico.
abstract: BACKGROUND
  A growing number of studies link chronic exposure to inorganic arsenic (iAs) with the risk of diabetes. Many of these studies assessed iAs exposure by measuring arsenic (As) species in urine. However, this approach has been criticized because of uncertainties associated with renal function and urine dilution in diabetic individuals.
  
  
  OBJECTIVE
  Our goal was to examine associations between the prevalence of diabetes and concentrations of As species in exfoliated urothelial cells (EUC) as an alternative to the measures of As in urine.
  
  
  METHODS
  We measured concentrations of trivalent and pentavalent iAs methyl-As (MAs) and dimethyl-As (DMAs) species in EUC from 374 residents of Chihuahua, Mexico, who were exposed to iAs in drinking water. We used fasting plasma glucose, glucose tolerance tests, and self-reported diabetes diagnoses or medication to identify diabetic participants. Associations between As species in EUC and diabetes were estimated using logistic and linear regression, adjusting for age, sex, and body mass index.
  
  
  RESULTS
  Interquartile-range increases in trivalent, but not pentavalent, As species in EUC were positively and significantly associated with diabetes, with ORs of 1.57 (95% CI: 1.19, 2.07) for iAsIII, 1.63 (1.24, 2.15) for MAsIII, and 1.31 (0.96, 1.84) for DMAsIII. DMAs/MAs and DMAs/iAs ratios were negatively associated with diabetes (OR = 0.62; 95% CI: 0.47, 0.83 and OR = 0.72; 95% CI: 0.55, 0.96, respectively).
  
  
  CONCLUSIONS
  Our data suggest that uncertainties associated with measures of As species in urine may be avoided by using As species in EUC as markers of iAs exposure and metabolism. Our results provide additional support to previous findings suggesting that trivalent As species may be responsible for associations between diabetes and chronic iAs exposure.
authors.affiliation: Curriculum in Toxicology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
authors.forename: Jenna M
authors.initials: JM
authors.lastname: Currier
authors.forename: María C
authors.initials: MC
authors.lastname: Ishida
authors.forename: Carmen
authors.initials: C
authors.lastname: González-Horta
authors.forename: Blanca
authors.initials: B
authors.lastname: Sánchez-Ramírez
authors.forename: Lourdes
authors.initials: L
authors.lastname: Ballinas-Casarrubias
authors.forename: Daniela S
authors.initials: DS
authors.lastname: Gutiérrez-Torres
authors.forename: Roberto Hernández
authors.initials: RH
authors.lastname: Cerón
authors.forename: Damián Viniegra
authors.initials: DV
authors.lastname: Morales
authors.forename: Francisco A Baeza
authors.initials: FA
authors.lastname: Terrazas
authors.forename: Luz M
authors.initials: LM
authors.lastname: Del Razo
authors.forename: Gonzalo G
authors.initials: GG
authors.lastname: García-Vargas
authors.forename: R Jesse
authors.initials: RJ
authors.lastname: Saunders
authors.forename: Zuzana
authors.initials: Z
authors.lastname: Drobná
authors.forename: Rebecca C
authors.initials: RC
authors.lastname: Fry
authors.forename: Tomáš
authors.initials: T
authors.lastname: Matoušek
authors.forename: John B
authors.initials: JB
authors.lastname: Buse
authors.forename: Michelle A
authors.initials: MA
authors.lastname: Mendez
authors.forename: Dana
authors.initials: D
authors.lastname: Loomis
authors.forename: Miroslav
authors.initials: M
authors.lastname: Stýblo
mesh_terms: D000328:Adult; D001151:Arsenic / Q000032:analysis / Q000378:metabolism / Q000652:urine*; D020261:Arsenic Poisoning; D001152:Arsenicals / Q000032:analysis / Q000378:metabolism / Q000652:urine; D015415:Biomarkers / Q000378:metabolism; D001786:Blood Glucose / Q000032:analysis; D003920:Diabetes Mellitus / Q000139:chemically induced / Q000453:epidemiology*; D004781:Environmental Exposure / Q000009:adverse effects / Q000706:statistics & numerical data*; D004847:Epithelial Cells / Q000737:chemistry / Q000378:metabolism; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D008297:Male; D008800:Mexico / Q000453:epidemiology; D008875:Middle Aged; D015995:Prevalence; D019459:Urothelium / Q000737:chemistry / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000378:metabolism / Q000652:urine*; D014881:Water Supply / Q000032:analysis / Q000706:statistics & numerical data
chemical_list: D001152:Arsenicals; D015415:Biomarkers; D001786:Blood Glucose; D014874:Water Pollutants, Chemical; D001151:Arsenic